1
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Dong C, Carnicer-Lombarte A, Bonafè F, Huang B, Middya S, Jin A, Tao X, Han S, Bance M, Barone DG, Fraboni B, Malliaras GG. Electrochemically actuated microelectrodes for minimally invasive peripheral nerve interfaces. NATURE MATERIALS 2024; 23:969-976. [PMID: 38671159 PMCID: PMC11230894 DOI: 10.1038/s41563-024-01886-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 03/31/2024] [Indexed: 04/28/2024]
Abstract
Electrode arrays that interface with peripheral nerves are used in the diagnosis and treatment of neurological disorders; however, they require complex placement surgeries that carry a high risk of nerve injury. Here we leverage recent advances in soft robotic actuators and flexible electronics to develop highly conformable nerve cuffs that combine electrochemically driven conducting-polymer-based soft actuators with low-impedance microelectrodes. Driven with applied voltages as small as a few hundreds of millivolts, these cuffs allow active grasping or wrapping around delicate nerves. We validate this technology using in vivo rat models, showing that the cuffs form and maintain a self-closing and reliable bioelectronic interface with the sciatic nerve of rats without the use of surgical sutures or glues. This seamless integration of soft electrochemical actuators with neurotechnology offers a path towards minimally invasive intraoperative monitoring of nerve activity and high-quality bioelectronic interfaces.
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Affiliation(s)
- Chaoqun Dong
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | | | - Filippo Bonafè
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - Botian Huang
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Sagnik Middya
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Amy Jin
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Xudong Tao
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
| | - Sanggil Han
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Nano-Bioengineering, Incheon National University, Incheon, Republic of Korea
| | - Manohar Bance
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Damiano G Barone
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | - Beatrice Fraboni
- Department of Physics and Astronomy, University of Bologna, Bologna, Italy
| | - George G Malliaras
- Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge, UK.
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2
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Han W, Gao W, Wang X. Enhanced Magnetic Soft Robotics: Integrating Fiber Optics and 3D Printing for Rapid Actuation and Precision Sensing. ACS APPLIED MATERIALS & INTERFACES 2024; 16:30396-30407. [PMID: 38820388 DOI: 10.1021/acsami.4c04586] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2024]
Abstract
Timely, accurate, and rapid grasping of dynamic change information in magnetic actuation soft robots is essential for advancing their evolution toward intelligent, integrated, and multifunctional systems. However, existing magnetic-actuation soft robots lack effective functions for integrating sensing and actuation. Herein, we demonstrate the integration of distributed fiber optics technology with advanced-programming 3D printing techniques. This integration provides our soft robots unique capabilities such as integrated sensing, precise shape reconstruction, controlled deformation, and sophisticated magnetic navigation. By utilizing an improved magneto-mechanical coupling model and an advanced inversion algorithm, we successfully achieved real-time reconstruction of complex structures, such as 'V', 'N', and 'M' shapes and gripper designs, with a notable response time of 34 ms. Additionally, our robots demonstrate proficiency in magnetic navigation and closed-loop deformation control, making them ideal for operation in confined or obscured environments. This work thus provides a transformative strategy to meet unmet demands in the rapidly growing field of soft robotics, especially in establishing the theoretical and technological foundation for constructing digitized robots.
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Affiliation(s)
- Wenheng Han
- Key Laboratory of Mechanics on Western Disaster and Environment, MoE, College of Civil Engineering and Mechanic, Key Laboratory of Special Function Materials and Structure Design of Ministry of Education, Lanzhou University, Lanzhou 730000, PR China
| | - Wei Gao
- School of Science, Lanzhou University of Technology, Lanzhou 730050, PR China
| | - Xingzhe Wang
- Key Laboratory of Mechanics on Western Disaster and Environment, MoE, College of Civil Engineering and Mechanic, Key Laboratory of Special Function Materials and Structure Design of Ministry of Education, Lanzhou University, Lanzhou 730000, PR China
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3
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Wang T, Jin T, Lin W, Lin Y, Liu H, Yue T, Tian Y, Li L, Zhang Q, Lee C. Multimodal Sensors Enabled Autonomous Soft Robotic System with Self-Adaptive Manipulation. ACS NANO 2024; 18:9980-9996. [PMID: 38387068 DOI: 10.1021/acsnano.3c11281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/24/2024]
Abstract
Human hands are amazingly skilled at recognizing and handling objects of different sizes and shapes. To date, soft robots rarely demonstrate autonomy equivalent to that of humans for fine perception and dexterous operation. Here, an intelligent soft robotic system with autonomous operation and multimodal perception ability is developed by integrating capacitive sensors with triboelectric sensor. With distributed multiple sensors, our robot system can not only sense and memorize multimodal information but also enable an adaptive grasping method for robotic positioning and grasp control, during which the multimodal sensory information can be captured sensitively and fused at feature level for crossmodally recognizing objects, leading to a highly enhanced recognition capability. The proposed system, combining the performance and physical intelligence of biological systems (i.e., self-adaptive behavior and multimodal perception), will greatly advance the integration of soft actuators and robotics in many fields.
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Affiliation(s)
- Tianhong Wang
- Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai 200444, People's Republic of China
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
- School of Artificial Intelligence, Shanghai University, Shanghai 200444, People's Republic of China
- Advanced Robotics Centre, National University of Singapore, Singapore 117608, Singapore
| | - Tao Jin
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
- School of Artificial Intelligence, Shanghai University, Shanghai 200444, People's Republic of China
- Advanced Robotics Centre, National University of Singapore, Singapore 117608, Singapore
| | - Weiyang Lin
- Research Institute of Intelligent Control and Systems, Harbin Institute of Technology, Harbin 150001, People's Republic of China
| | - Yangqiao Lin
- Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai 200444, People's Republic of China
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
| | - Hongfei Liu
- Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai 200444, People's Republic of China
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
- Department of Mechanical and Mechatronics Engineering, The University of Auckland, Auckland 1010, New Zealand
| | - Tao Yue
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
- School of Artificial Intelligence, Shanghai University, Shanghai 200444, People's Republic of China
| | - Yingzhong Tian
- Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai 200444, People's Republic of China
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
| | - Long Li
- Shanghai Key Laboratory of Intelligent Manufacturing and Robotics, Shanghai University, Shanghai 200444, People's Republic of China
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
- School of Artificial Intelligence, Shanghai University, Shanghai 200444, People's Republic of China
| | - Quan Zhang
- School of Mechatronic Engineering and Automation, Shanghai University, Shanghai 200444, People's Republic of China
- School of Artificial Intelligence, Shanghai University, Shanghai 200444, People's Republic of China
| | - Chengkuo Lee
- Department of Electrical & Computer Engineering, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore
- Center for Intelligent Sensors and MEMS, National University of Singapore, 4 Engineering Drive 3, Singapore 117583, Singapore
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4
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Kwon H, Yang Y, Kim G, Gim D, Ha M. Anisotropy in magnetic materials for sensors and actuators in soft robotic systems. NANOSCALE 2024; 16:6778-6819. [PMID: 38502047 DOI: 10.1039/d3nr05737b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/20/2024]
Abstract
The field of soft intelligent robots has rapidly developed, revealing extensive potential of these robots for real-world applications. By mimicking the dexterities of organisms, robots can handle delicate objects, access remote areas, and provide valuable feedback on their interactions with different environments. For autonomous manipulation of soft robots, which exhibit nonlinear behaviors and infinite degrees of freedom in transformation, innovative control systems integrating flexible and highly compliant sensors should be developed. Accordingly, sensor-actuator feedback systems are a key strategy for precisely controlling robotic motions. The introduction of material magnetism into soft robotics offers significant advantages in the remote manipulation of robotic operations, including touch or touchless detection of dynamically changing shapes and positions resulting from the actuations of robots. Notably, the anisotropies in the magnetic nanomaterials facilitate the perception and response with highly selective, directional, and efficient ways used for both sensors and actuators. Accordingly, this review provides a comprehensive understanding of the origins of magnetic anisotropy from both intrinsic and extrinsic factors and summarizes diverse magnetic materials with enhanced anisotropy. Recent developments in the design of flexible sensors and soft actuators based on the principle of magnetic anisotropy are outlined, specifically focusing on their applicabilities in soft robotic systems. Finally, this review addresses current challenges in the integration of sensors and actuators into soft robots and offers promising solutions that will enable the advancement of intelligent soft robots capable of efficiently executing complex tasks relevant to our daily lives.
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Affiliation(s)
- Hyeokju Kwon
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea.
| | - Yeonhee Yang
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea.
| | - Geonsu Kim
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea.
| | - Dongyeong Gim
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea.
| | - Minjeong Ha
- School of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Gwangju 61005, Republic of Korea.
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5
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Blanc B, Zhang Z, Liu E, Zhou N, Dellatolas I, Aghvami A, Yi H, Fraden S. Active Pulsatile Gels: From a Chemical Microreactor to a Polymeric Actuator. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2024; 40:6862-6868. [PMID: 38385757 DOI: 10.1021/acs.langmuir.3c03784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2024]
Abstract
We report on a synthesis protocol, experimental characterization, and theoretical modeling of active pulsatile Belousov-Zhabotinsky (BZ) hydrogels. Our two-step synthesis technique allows independent optimization of the geometry, the chemical, and the mechanical properties of BZ gels. We identify the role of the surrounding medium chemistry and gel radius for the occurrence of BZ gel oscillations, quantified by the Damköhler number, which is the ratio of chemical reaction to diffusion rates. Tuning the BZ gel size to maximize its chemomechanical oscillation amplitude, we find that its oscillatory strain amplitude is limited by the time scale of gel swelling relative to the chemical oscillation period. Our experimental findings are in good agreement with a Vanag-Epstein model of BZ chemistry and a Tanaka Fillmore theory of gel swelling dynamics.
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Affiliation(s)
- Baptiste Blanc
- Department of Physics, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Zhenkun Zhang
- Key Laboratory of Functional Polymer Materials of Ministry of Education, Institute of Polymer Chemistry, College of Chemistry, Nankai University, 300071 Tianjin, China
| | - Eric Liu
- Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Ning Zhou
- Department of Chemistry, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Ippolyti Dellatolas
- Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Ali Aghvami
- Department of Physics, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
| | - Hyunmin Yi
- Department of Chemical and Biological Engineering, Tufts University, Medford, Massachusetts 02155, United States
| | - Seth Fraden
- Department of Physics, Brandeis University, 415 South Street, Waltham, Massachusetts 02454, United States
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6
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Firoozan M, Baniassadi M, Baghani M, Chortos A. In silico optimization of aligned fiber electrodes for dielectric elastomer actuators. Sci Rep 2024; 14:4703. [PMID: 38409334 PMCID: PMC10897417 DOI: 10.1038/s41598-024-54931-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2023] [Accepted: 02/19/2024] [Indexed: 02/28/2024] Open
Abstract
Dielectric elastomer actuators (DEAs) exhibit fast actuation and high efficiencies, enabling applications in optics, wearable haptics, and insect-scale robotics. However, the non-uniformity and high sheet resistance of traditional soft electrodes based on nanomaterials limit the performance and operating frequency of the devices. In this work, we computationally investigate electrodes composed of arrays of stiff fiber electrodes. Aligning the fibers along one direction creates an electrode layer that exhibits zero stiffness in one direction and is predicted to possess high and uniform sheet resistance. A comprehensive parameter study of the fiber density and dielectric thickness reveals that the fiber density primary determines the electric field localization while the dielectric thickness primarily determines the unit cell stiffness. These trends identify an optimal condition for the actuation performance of the aligned electrode DEAs. This work demonstrates that deterministically designed electrodes composed of stiff materials could provide a new paradigm with the potential to surpass the performance of traditional soft planar electrodes.
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Affiliation(s)
- Mohammadreza Firoozan
- School of Mechanical Engineering, Purdue University, West Lafayette, USA
- School of Mechanical Engineering, University of Tehran, Tehran, Iran
| | - Majid Baniassadi
- School of Mechanical Engineering, University of Tehran, Tehran, Iran
| | - Mostafa Baghani
- School of Mechanical Engineering, University of Tehran, Tehran, Iran
| | - Alex Chortos
- School of Mechanical Engineering, Purdue University, West Lafayette, USA.
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7
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Hong S, Park T, Lee J, Ji Y, Walsh J, Yu T, Park JY, Lim J, Benito Alston C, Solorio L, Lee H, Kim YL, Kim DR, Lee CH. Rapid Self-Healing Hydrogel with Ultralow Electrical Hysteresis for Wearable Sensing. ACS Sens 2024; 9:662-673. [PMID: 38300847 DOI: 10.1021/acssensors.3c01835] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2024]
Abstract
Self-healing hydrogels are in high demand for wearable sensing applications due to their remarkable deformability, high ionic and electrical conductivity, self-adhesiveness to human skin, as well as resilience to both mechanical and electrical damage. However, these hydrogels face challenges such as delayed healing times and unavoidable electrical hysteresis, which limit their practical effectiveness. Here, we introduce a self-healing hydrogel that exhibits exceptionally rapid healing with a recovery time of less than 0.12 s and an ultralow electrical hysteresis of less than 0.64% under cyclic strains of up to 500%. This hydrogel strikes an ideal balance, without notable trade-offs, between properties such as softness, deformability, ionic and electrical conductivity, self-adhesiveness, response and recovery times, durability, overshoot behavior, and resistance to nonaxial deformations such as twisting, bending, and pressing. Owing to this unique combination of features, the hydrogel is highly suitable for long-term, durable use in wearable sensing applications, including monitoring body movements and electrophysiological activities on the skin.
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Affiliation(s)
- Seokkyoon Hong
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Taewoong Park
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Junsang Lee
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- School of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Yuhyun Ji
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Julia Walsh
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Tianhao Yu
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jae Young Park
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Jongcheon Lim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Claudia Benito Alston
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Luis Solorio
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Hyowon Lee
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Center for Implantable Devices, Purdue University, West Lafayette, Indiana 47907, United States
| | - Young L Kim
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
| | - Dong Rip Kim
- School of Mechanical Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Chi Hwan Lee
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- Center for Implantable Devices, Purdue University, West Lafayette, Indiana 47907, United States
- School of Mechanical Engineering, Purdue University, West Lafayette, Indiana 47907, United States
- School of Materials Engineering, Purdue University, West Lafayette, Indiana 47907, United States
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8
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Wu T, Liu Z, Wang B, Ma Z, Ma D, Deng X. A Versatile Topology-Optimized Compliant Actuator for Soft Robotic Gripper and Walking Robot. Soft Robot 2024; 11:157-170. [PMID: 37819714 DOI: 10.1089/soro.2022.0247] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/13/2023] Open
Abstract
The remarkable interaction capabilities of soft robots within various environments have captured substantial attention from researchers. In recent years, bionics has provided a rich inspiration for the design of soft robots. Nevertheless, predicting the locomotion of soft actuators and determining material layouts solely based on intuition or experience remain a formidable challenge. Previous actuators predominantly targeted separate applications, leading to elevated costs and diminished interchangeability. The objective of this article is to extract the common requirements of diverse application domains and develop a versatile compliant actuator. A mathematical model of the compliant mechanism is proposed under the framework of topology optimization, resulting in an optimal distribution of both structure and material. Through comparison with empirical and semioptimal designs, the results show that the proposed versatile actuator has the advantages of both stiffness and flexibility. We propose an associative design strategy for soft grippers and walking robots. The soft gripper can perfectly complete adaptive grasping of objects with varying sizes, shapes, and masses. The successful in-water gripping experiment underscores the robust cross-medium operational capabilities of the soft gripper. Notably, our experimental results show that the walking robot can move quickly for 5 cycles in 8.25 s and can guarantee the control accuracy of continuous motion. Moreover, the robot swiftly switches walking directions within a mere 0.45 s. The optimization and design strategy presented in this article can furnish novel insights for shaping the next generation of soft robots.
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Affiliation(s)
- Tingke Wu
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- MOE Key Laboratory of Hydrodynamics, Shanghai Jiao Tong University, Shanghai, China
| | - Zhuyong Liu
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- MOE Key Laboratory of Hydrodynamics, Shanghai Jiao Tong University, Shanghai, China
| | - Boyang Wang
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- MOE Key Laboratory of Hydrodynamics, Shanghai Jiao Tong University, Shanghai, China
| | - Ziqi Ma
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- MOE Key Laboratory of Hydrodynamics, Shanghai Jiao Tong University, Shanghai, China
| | - Daolin Ma
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China
- State Key Laboratory of Ocean Engineering, Shanghai Jiao Tong University, Shanghai, China
- MOE Key Laboratory of Hydrodynamics, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaowei Deng
- Department of Engineering Mechanics, School of Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai, China
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9
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Li L, Wang X, Gao S, Zheng S, Zou X, Xiong J, Li W, Yan F. High-Toughness and High-Strength Solvent-Free Linear Poly(ionic liquid) Elastomers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2308547. [PMID: 37816506 DOI: 10.1002/adma.202308547] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2023] [Revised: 10/08/2023] [Indexed: 10/12/2023]
Abstract
Solvent-free elastomers, unlike gels, do not suffer from solvent evaporation and leakage in practical applications. However, it is challenging to realize the preparation of high-toughness (with both high stress and strain) ionic elastomers. Herein, high-toughness linear poly(ionic liquid) (PIL) elastomers are constructed via supramolecular ionic networks formed by the polymerization of halometallate ionic liquid (IL) monomers, without any chemical crosslinking. The obtained linear PIL elastomers exhibit high strength (16.5 MPa), Young's modulus (157.49 MPa), toughness (130.31 MJ m-3 ), and high crack propagation insensitivity (fracture energy 243.37 kJ m-2 ), owing to the enhanced intermolecular noncovalent interactions of PIL chains. Furthermore, PIL elastomer-based strain, pressure, and touch sensors have shown high sensitivity. The linear noncovalent crosslinked network endows the PIL elastomers with self-healing and recyclable properties, and broad application prospects in the fields of flexible sensor devices, health monitoring, and human-machine interaction.
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Affiliation(s)
- Lingling Li
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Xiaowei Wang
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Shuna Gao
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Sijie Zheng
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Xiuyang Zou
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Jiaofeng Xiong
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Weizheng Li
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
| | - Feng Yan
- Jiangsu Engineering Laboratory of Novel Functional Polymeric Materials, Jiangsu Key Laboratory of Advanced Negative Carbon Technologies, Suzhou Key Laboratory of Soft Material and New Energy, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, China
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10
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Del Dottore E, Mondini A, Rowe N, Mazzolai B. A growing soft robot with climbing plant-inspired adaptive behaviors for navigation in unstructured environments. Sci Robot 2024; 9:eadi5908. [PMID: 38232147 DOI: 10.1126/scirobotics.adi5908] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 12/14/2023] [Indexed: 01/19/2024]
Abstract
Self-growing robots are an emerging solution in soft robotics for navigating, exploring, and colonizing unstructured environments. However, their ability to grow and move in heterogeneous three-dimensional (3D) spaces, comparable with real-world conditions, is still developing. We present an autonomous growing robot that draws inspiration from the behavioral adaptive strategies of climbing plants to navigate unstructured environments. The robot mimics climbing plants' apical shoot to sense and coordinate additive adaptive growth via an embedded additive manufacturing mechanism and a sensorized tip. Growth orientation, comparable with tropisms in real plants, is dictated by external stimuli, including gravity, light, and shade. These are incorporated within a vector field method to implement the preferred adaptive behavior for a given environment and task, such as growth toward light and/or against gravity. We demonstrate the robot's ability to navigate through growth in relation to voids, potential supports, and thoroughfares in otherwise complex habitats. Adaptive twining around vertical supports can provide an escape from mechanical stress due to self-support, reduce energy expenditure for construction costs, and develop an anchorage point to support further growth and crossing gaps. The robot adapts its material printing parameters to develop a light body and fast growth to twine on supports or a tougher body to enable self-support and cross gaps. These features, typical of climbing plants, highlight a potential for adaptive robots and their on-demand manufacturing. They are especially promising for applications in exploring, monitoring, and interacting with unstructured environments or in the autonomous construction of complex infrastructures.
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Affiliation(s)
- Emanuela Del Dottore
- Bioinspired Soft Robotics Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Alessio Mondini
- Bioinspired Soft Robotics Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Nick Rowe
- AMAP Laboratory, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, France
| | - Barbara Mazzolai
- Bioinspired Soft Robotics Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
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11
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Riener R, Rabezzana L, Zimmermann Y. Do robots outperform humans in human-centered domains? Front Robot AI 2023; 10:1223946. [PMID: 38023587 PMCID: PMC10661952 DOI: 10.3389/frobt.2023.1223946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2023] [Accepted: 10/09/2023] [Indexed: 12/01/2023] Open
Abstract
The incessant progress of robotic technology and rationalization of human manpower induces high expectations in society, but also resentment and even fear. In this paper, we present a quantitative normalized comparison of performance, to shine a light onto the pressing question, "How close is the current state of humanoid robotics to outperforming humans in their typical functions (e.g., locomotion, manipulation), and their underlying structures (e.g., actuators/muscles) in human-centered domains?" This is the most comprehensive comparison of the literature so far. Most state-of-the-art robotic structures required for visual, tactile, or vestibular perception outperform human structures at the cost of slightly higher mass and volume. Electromagnetic and fluidic actuation outperform human muscles w.r.t. speed, endurance, force density, and power density, excluding components for energy storage and conversion. Artificial joints and links can compete with the human skeleton. In contrast, the comparison of locomotion functions shows that robots are trailing behind in energy efficiency, operational time, and transportation costs. Robots are capable of obstacle negotiation, object manipulation, swimming, playing soccer, or vehicle operation. Despite the impressive advances of humanoid robots in the last two decades, current robots are not yet reaching the dexterity and versatility to cope with more complex manipulation and locomotion tasks (e.g., in confined spaces). We conclude that state-of-the-art humanoid robotics is far from matching the dexterity and versatility of human beings. Despite the outperforming technical structures, robot functions are inferior to human ones, even with tethered robots that could place heavy auxiliary components off-board. The persistent advances in robotics let us anticipate the diminishing of the gap.
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Affiliation(s)
- Robert Riener
- Sensory-Motor Systems Laboratory, Institute of Robotics and Intelligent Systems, ETH Zurich, Zurich, Switzerland
- Paraplegic Center, University Hospital Balgrist, University of Zurich, Zurich, Switzerland
| | - Luca Rabezzana
- Sensory-Motor Systems Laboratory, Institute of Robotics and Intelligent Systems, ETH Zurich, Zurich, Switzerland
| | - Yves Zimmermann
- Sensory-Motor Systems Laboratory, Institute of Robotics and Intelligent Systems, ETH Zurich, Zurich, Switzerland
- Robotic-Systems Laboratory, Institute of Robotics and Intelligent Systems, ETH Zurich, Zurich, Switzerland
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12
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Li L, Tian W, VahidMohammadi A, Rostami J, Chen B, Matthews K, Ram F, Pettersson T, Wågberg L, Benselfelt T, Gogotsi Y, Berglund LA, Hamedi MM. Ultrastrong Ionotronic Films Showing Electrochemical Osmotic Actuation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2301163. [PMID: 37491007 DOI: 10.1002/adma.202301163] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 06/07/2023] [Indexed: 07/27/2023]
Abstract
A multifunctional soft material with high ionic and electrical conductivity, combined with high mechanical properties and the ability to change shape can enable bioinspired responsive devices and systems. The incorporation of all these characteristics in a single material is very challenging, as the improvement of one property tends to reduce other properties. Here, a nanocomposite film based on charged, high-aspect-ratio 1D flexible nanocellulose fibrils, and 2D Ti3 C2 Tx MXene is presented. The self-assembly process results in a stratified structure with the nanoparticles aligned in-plane, providing high ionotronic conductivity and mechanical strength, as well as large water uptake. In hydrogel form with 20 wt% liquid, the electrical conductivity is over 200 S cm-1 and the in-plane tensile strength is close to 100 MPa. This multifunctional performance results from the uniquely layered composite structure at nano- and mesoscales. A new type of electrical soft actuator is assembled where voltage as low as ±1 V resulted in osmotic effects and giant reversible out-of-plane swelling, reaching 85% strain.
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Affiliation(s)
- Lengwan Li
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Weiqian Tian
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
- School of Materials Science and Engineering, Ocean University of China, Qingdao, Shandong, 266100, China
| | - Armin VahidMohammadi
- A.J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering, Drexel University, Philadelphia, PA, 19104, USA
| | - Jowan Rostami
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Bin Chen
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Kyle Matthews
- A.J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering, Drexel University, Philadelphia, PA, 19104, USA
| | - Farsa Ram
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Torbjörn Pettersson
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Lars Wågberg
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Tobias Benselfelt
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Yury Gogotsi
- A.J. Drexel Nanomaterials Institute and Department of Materials Science and Engineering, Drexel University, Philadelphia, PA, 19104, USA
| | - Lars A Berglund
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
| | - Mahiar Max Hamedi
- Department of Fibre and Polymer Technology, Wallenberg Wood Science Center, KTH Royal Institute of Technology, Stockholm, SE-100 44, Sweden
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13
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Benselfelt T, Shakya J, Rothemund P, Lindström SB, Piper A, Winkler TE, Hajian A, Wågberg L, Keplinger C, Hamedi MM. Electrochemically Controlled Hydrogels with Electrotunable Permeability and Uniaxial Actuation. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2303255. [PMID: 37451686 DOI: 10.1002/adma.202303255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 05/26/2023] [Accepted: 07/11/2023] [Indexed: 07/18/2023]
Abstract
The unique properties of hydrogels enable the design of life-like soft intelligent systems. However, stimuli-responsive hydrogels still suffer from limited actuation control. Direct electronic control of electronically conductive hydrogels can solve this challenge and allow direct integration with modern electronic systems. An electrochemically controlled nanowire composite hydrogel with high in-plane conductivity that stimulates a uniaxial electrochemical osmotic expansion is demonstrated. This materials system allows precisely controlled shape-morphing at only -1 V, where capacitive charging of the hydrogel bulk leads to a large uniaxial expansion of up to 300%, caused by the ingress of ≈700 water molecules per electron-ion pair. The material retains its state when turned off, which is ideal for electrotunable membranes as the inherent coupling between the expansion and mesoporosity enables electronic control of permeability for adaptive separation, fractionation, and distribution. Used as electrochemical osmotic hydrogel actuators, they achieve an electroactive pressure of up to 0.7 MPa (1.4 MPa vs dry) and a work density of ≈150 kJ m-3 (2 MJ m-3 vs dry). This new materials system paves the way to integrate actuation, sensing, and controlled permeation into advanced soft intelligent systems.
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Affiliation(s)
- Tobias Benselfelt
- Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden
| | - Jyoti Shakya
- Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden
| | - Philipp Rothemund
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| | - Stefan B Lindström
- Department of Management and Engineering, Division of Solid Mechanics, Linköping University, Linköping, 58183, Sweden
| | - Andrew Piper
- Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden
| | - Thomas E Winkler
- Institute of Microtechnology & Center of Pharmaceutical Engineering, Technische Universität Braunschweig, 38106, Braunschweig, Germany
| | - Alireza Hajian
- Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden
| | - Lars Wågberg
- Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden
| | - Christoph Keplinger
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
- Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, CO, 80309, USA
- Materials Science and Engineering Program, University of Colorado, Boulder, CO, 80309, USA
| | - Mahiar Max Hamedi
- Department of Fibre and Polymer Technology, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, Stockholm, 100 44, Sweden
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14
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Li C, Schramma N, Wang Z, Qari NF, Jalaal M, Latz MI, Cai S. Ultrasensitive and robust mechanoluminescent living composites. SCIENCE ADVANCES 2023; 9:eadi8643. [PMID: 37862415 PMCID: PMC10588950 DOI: 10.1126/sciadv.adi8643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 09/19/2023] [Indexed: 10/22/2023]
Abstract
Mechanosensing, the transduction of extracellular mechanical stimuli into intracellular biochemical signals, is a fundamental property of living cells. However, endowing synthetic materials with mechanosensing capabilities comparable to biological levels is challenging. Here, we developed ultrasensitive and robust mechanoluminescent living composites using hydrogels embedded with dinoflagellates, unicellular microalgae with a near-instantaneous and ultrasensitive bioluminescent response to mechanical stress. Not only did embedded dinoflagellates retain their intrinsic mechanoluminescence, but with hydrophobic coatings, living composites had a lifetime of ~5 months under harsh conditions with minimal maintenance. We 3D-printed living composites into large-scale mechanoluminescent structures with high spatial resolution, and we also enhanced their mechanical properties with double-network hydrogels. We propose a counterpart mathematical model that captured experimental mechanoluminescent observations to predict mechanoluminescence based on deformation and applied stress. We also demonstrated the use of the mechanosensing composites for biomimetic soft actuators that emitted colored light upon magnetic actuation. These mechanosensing composites have substantial potential in biohybrid sensors and robotics.
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Affiliation(s)
- Chenghai Li
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nico Schramma
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, Amsterdam 1098XH, Netherlands
| | - Zijun Wang
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Nada F. Qari
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093, USA
| | - Maziyar Jalaal
- Van der Waals-Zeeman Institute, Institute of Physics, University of Amsterdam, Science Park 904, Amsterdam 1098XH, Netherlands
| | - Michael I. Latz
- Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093, USA
| | - Shengqiang Cai
- Department of Mechanical and Aerospace Engineering, University of California, San Diego, La Jolla, CA 92093, USA
- Materials Science and Engineering Program, University of California, San Diego, La Jolla, CA 92093, USA
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15
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Müller FJ, Isa L, Vermant J. Toughening colloidal gels using rough building blocks. Nat Commun 2023; 14:5309. [PMID: 37652918 PMCID: PMC10471594 DOI: 10.1038/s41467-023-41098-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 08/22/2023] [Indexed: 09/02/2023] Open
Abstract
Colloidal gels, commonly used as mesoporous intermediates or functional materials, suffer from brittleness, often showing small yield strains on the order of 1% or less for gelled colloidal suspensions. The short-range adhesive forces in most such gels are central forces-combined with the smooth morphology of particles, the resistance to yielding and shear-induced restructuring is limited. In this study, we propose an innovative approach to improve colloidal gels by introducing surface roughness to the particles to change the yield strain, giving rise to non-central interactions. To elucidate the effects of particle roughness on gel properties, we prepared thermoreversible gels made from rough or smooth silica particles using a reliable click-like-chemistry-based surface grafting technique. Rheological and optical characterization revealed that rough particle gels exhibit enhanced toughness and self-healing properties. These remarkable properties can be utilized in various applications, such as xerogel fabrication and high-fidelity extrusion 3D-printing, as we demonstrate in this study.
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Affiliation(s)
| | - Lucio Isa
- Department of Materials, ETH Zurich, Switzerland
| | - Jan Vermant
- Department of Materials, ETH Zurich, Switzerland.
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16
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Johnson BK, Naris M, Sundaram V, Volchko A, Ly K, Mitchell SK, Acome E, Kellaris N, Keplinger C, Correll N, Humbert JS, Rentschler ME. A multifunctional soft robotic shape display with high-speed actuation, sensing, and control. Nat Commun 2023; 14:4516. [PMID: 37524731 PMCID: PMC10390478 DOI: 10.1038/s41467-023-39842-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 07/03/2023] [Indexed: 08/02/2023] Open
Abstract
Shape displays which actively manipulate surface geometry are an expanding robotics domain with applications to haptics, manufacturing, aerodynamics, and more. However, existing displays often lack high-fidelity shape morphing, high-speed deformation, and embedded state sensing, limiting their potential uses. Here, we demonstrate a multifunctional soft shape display driven by a 10 × 10 array of scalable cellular units which combine high-speed electrohydraulic soft actuation, magnetic-based sensing, and control circuitry. We report high-performance reversible shape morphing up to 50 Hz, sensing of surface deformations with 0.1 mm sensitivity and external forces with 50 mN sensitivity in each cell, which we demonstrate across a multitude of applications including user interaction, image display, sensing of object mass, and dynamic manipulation of solids and liquids. This work showcases the rich multifunctionality and high-performance capabilities that arise from tightly-integrating large numbers of electrohydraulic actuators, soft sensors, and controllers at a previously undemonstrated scale in soft robotics.
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Affiliation(s)
- B K Johnson
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
| | - M Naris
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
| | - V Sundaram
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
| | - A Volchko
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
| | - K Ly
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
| | - S K Mitchell
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
- Artimus Robotics, Boulder, CO, USA
| | - E Acome
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
- Artimus Robotics, Boulder, CO, USA
| | - N Kellaris
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA
- Artimus Robotics, Boulder, CO, USA
- Materials Science and Engineering Program, University of Colorado Boulder, Boulder, CO, USA
| | - C Keplinger
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA.
- Materials Science and Engineering Program, University of Colorado Boulder, Boulder, CO, USA.
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany.
| | - N Correll
- Department of Computer Science, University of Colorado Boulder, Boulder, CO, USA.
| | - J S Humbert
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA.
| | - M E Rentschler
- Paul M. Rady Mechanical Engineering, University of Colorado Boulder, Boulder, CO, USA.
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17
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Bin Asghar Abbasi B, Gigliotti M, Aloko S, Jolfaei MA, Spinks GM, Jiang Z. Designing strong, fast, high-performance hydrogel actuators. Chem Commun (Camb) 2023; 59:7141-7150. [PMID: 37194593 DOI: 10.1039/d3cc01545a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Hydrogel actuators displaying programmable shape transformations are particularly attractive for integration into future soft robotics with safe human-machine interactions. However, these materials are still in their infancy, and many significant challenges remain presenting impediments to their practical implementation, including poor mechanical properties, slow actuation speed and limited actuation performance. In this review, we discuss the recent advances in hydrogel designs to address these critical limitations. First, the material design concepts to improve mechanical properties of hydrogel actuators will be introduced. Examples are also included to highlight strategies to realize fast actuation speed. In addition, recent progress about creating strong and fast hydrogel actuators are sumarized. Finally, a discussion of different methods to realize high values in several aspects of actuation performance metrics for this class of materials is provided. The advances and challenges discussed in this highlight could provide useful guidelines for rational design to manipulate the properties of hydrogel actuators toward widespread real-world applications.
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Affiliation(s)
- Burhan Bin Asghar Abbasi
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Matthew Gigliotti
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Sinmisola Aloko
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Maryam Adavoudi Jolfaei
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Geoffrey M Spinks
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
| | - Zhen Jiang
- School of Mechanical, Materials, Mechatronic and Biomedical Engineering, University of Wollongong, Wollongong, NSW 2522, Australia.
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18
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Chen M, Gao M, Bai L, Zheng H, Qi HJ, Zhou K. Recent Advances in 4D Printing of Liquid Crystal Elastomers. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2209566. [PMID: 36461147 DOI: 10.1002/adma.202209566] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/22/2022] [Indexed: 06/09/2023]
Abstract
Liquid crystal elastomers (LCEs) are renowned for their large, reversible, and anisotropic shape change in response to various external stimuli due to their lightly cross-linked polymer networks with an oriented mesogen direction, thus showing great potential for applications in robotics, bio-medics, electronics, optics, and energy. To fully take advantage of the anisotropic stimuli-responsive behaviors of LCEs, it is preferable to achieve a locally controlled mesogen alignment into monodomain orientations. In recent years, the application of 4D printing to LCEs opens new doors for simultaneously programming the mesogen alignment and the 3D geometry, offering more opportunities and higher feasibility for the fabrication of 4D-printed LCE objects with desirable stimuli-responsive properties. Here, the state-of-the-art advances in 4D printing of LCEs are reviewed, with emphasis on both the mechanisms and potential applications. First, the fundamental properties of LCEs and the working principles of the representative 4D printing techniques are briefly introduced. Then, the fabrication of LCEs by 4D printing techniques and the advantages over conventional manufacturing methods are demonstrated. Finally, perspectives on the current challenges and potential development trends toward the 4D printing of LCEs are discussed, which may shed light on future research directions in this new field.
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Affiliation(s)
- Mei Chen
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- HP-NTU Digital Manufacturing Corporate Lab, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Ming Gao
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- HP-NTU Digital Manufacturing Corporate Lab, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Lichun Bai
- School of Traffic and Transportation Engineering, Central South University, Changsha, 410075, China
| | - Han Zheng
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - H Jerry Qi
- School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Kun Zhou
- Singapore Centre for 3D Printing, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- HP-NTU Digital Manufacturing Corporate Lab, School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore, 639798, Singapore
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19
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Benselfelt T, Rothemund P, Lee PS. Ultrafast, High-Strain, and Strong Uniaxial Hydrogel Actuators from Recyclable Nanofibril Networks. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2300487. [PMID: 37002908 DOI: 10.1002/adma.202300487] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/16/2023] [Revised: 03/13/2023] [Indexed: 06/02/2023]
Abstract
Polymer hydrogels mimic biological tissues and are suitable for future lifelike machines. However, their actuation is isotropic, so they must be crosslinked or placed in a turgor membrane to achieve high actuation pressures, severely impeding their performance. Here, it is shown that organizing cellulose nanofibrils (CNFs) in anisotropic hydrogel sheets leads to mechanical in-plane reinforcement that generates a uniaxial, out-of-plane strain with performance far surpassing polymer hydrogels. These fibrillar hydrogel actuators expand uniaxially by 250 times with an initial rate of 100-130% s-1 , compared to <10 times and <1% s-1 in directional strain rate for isotropic hydrogels, respectively. The blocking pressure reaches 0.9 MPa, similar to turgor actuators, while the time to reach 90% of the maximum pressure is 1-2 min, compared to 10 min to hours for polymer hydrogel actuators. Uniaxial actuators that lift objects 120 000 times their weight and soft grippers are showcased. In addition, the hydrogels can be recycled without a loss in performance. The uniaxial swelling allows adding channels through the gel for local solvent delivery, further increasing the actuation rate and cyclability. Thus, fibrillar networks can overcome the major drawbacks of hydrogel actuators and is a significant advancement towards hydrogel-based lifelike machines.
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Affiliation(s)
- Tobias Benselfelt
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
| | - Philipp Rothemund
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, 70569, Stuttgart, Germany
| | - Pooi See Lee
- School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore
- Singapore-HUJ Alliance for Research and Enterprise (SHARE), Smart Grippers for Soft Robotics (SGSR), Campus for Research Excellence and Technological Enterprise (CREATE), Singapore, 138602, Singapore
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20
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Abstract
Development and implementation of neuroprosthetic hands is a multidisciplinary field at the interface between humans and artificial robotic systems, which aims at replacing the sensorimotor function of the upper-limb amputees as their own. Although prosthetic hand devices with myoelectric control can be dated back to more than 70 years ago, their applications with anthropomorphic robotic mechanisms and sensory feedback functions are still at a relatively preliminary and laboratory stage. Nevertheless, a recent series of proof-of-concept studies suggest that soft robotics technology may be promising and useful in alleviating the design complexity of the dexterous mechanism and integration difficulty of multifunctional artificial skins, in particular, in the context of personalized applications. Here, we review the evolution of neuroprosthetic hands with the emerging and cutting-edge soft robotics, covering the soft and anthropomorphic prosthetic hand design and relating bidirectional neural interactions with myoelectric control and sensory feedback. We further discuss future opportunities on revolutionized mechanisms, high-performance soft sensors, and compliant neural-interaction interfaces for the next generation of neuroprosthetic hands.
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Affiliation(s)
- Guoying Gu
- Robotics Institute, State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
- Meta Robotics Institute, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ningbin Zhang
- Robotics Institute, State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chen Chen
- Robotics Institute, State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Haipeng Xu
- Robotics Institute, State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiangyang Zhu
- Robotics Institute, State Key Laboratory of Mechanical System and Vibration, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
- Meta Robotics Institute, Shanghai Jiao Tong University, Shanghai 200240, China
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21
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Yan Y, Duan S, Liu B, Wu S, Alsaid Y, Yao B, Nandi S, Du Y, Wang TW, Li Y, He X. Tough Hydrogel Electrolytes for Anti-Freezing Zinc-Ion Batteries. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2211673. [PMID: 36932878 DOI: 10.1002/adma.202211673] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/04/2023] [Indexed: 05/05/2023]
Abstract
As the soaring demand for energy storage continues to grow, batteries that can cope with extreme conditions are highly desired. Yet, existing battery materials are limited by weak mechanical properties and freeze-vulnerability, prohibiting safe energy storage in devices that are exposed to low temperature and unusual mechanical impacts. Herein, a fabrication method harnessing the synergistic effect of co-nonsolvency and "salting-out" that can produce poly(vinyl alcohol) hydrogel electrolytes with unique open-cell porous structures, composed of strongly aggregated polymer chains, and containing disrupted hydrogen bonds among free water molecules, is introduced. The hydrogel electrolyte simultaneously combines high strength (tensile strength 15.6 MPa), freeze-tolerance (< -77 °C), high mass transport (10× lower overpotential), and dendrite and parasitic reactions suppression for stable performance (30 000 cycles). The high generality of this method is further demonstrated with poly(N-isopropylacrylamide) and poly(N-tertbutylacrylamide-co-acrylamide) hydrogels. This work takes a further step toward flexible battery development for harsh environments.
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Affiliation(s)
- Yichen Yan
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Sidi Duan
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Bo Liu
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Shuwang Wu
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Yousif Alsaid
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Bowen Yao
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Sunny Nandi
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
- Department of Physics, Tezpur University, Assam, 784028, India
| | - Yingjie Du
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Ta-Wei Wang
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Yuzhang Li
- Department of Chemical and Biomolecular Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
| | - Ximin He
- Department of Materials Science and Engineering, University of California, Los Angeles, Los Angeles, CA, 90095, USA
- California Nanosystems Institute, Los Angeles, CA, 90095, USA
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22
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Zhao Y, Li Q, Liu Z, Alsaid Y, Shi P, Khalid Jawed M, He X. Sunlight-powered self-excited oscillators for sustainable autonomous soft robotics. Sci Robot 2023; 8:eadf4753. [PMID: 37075101 DOI: 10.1126/scirobotics.adf4753] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/21/2023]
Abstract
As the field of soft robotics advances, full autonomy becomes highly sought after, especially if robot motion can be powered by environmental energy. This would present a self-sustained approach in terms of both energy supply and motion control. Now, autonomous movement can be realized by leveraging out-of-equilibrium oscillatory motion of stimuli-responsive polymers under a constant light source. It would be more advantageous if environmental energy could be scavenged to power robots. However, generating oscillation becomes challenging under the limited power density of available environmental energy sources. Here, we developed fully autonomous soft robots with self-sustainability based on self-excited oscillation. Aided by modeling, we have successfully reduced the required input power density to around one-Sun level through a liquid crystal elastomer (LCE)-based bilayer structure. The autonomous motion of the low-intensity LCE/elastomer bilayer oscillator "LiLBot" under low energy supply was achieved by high photothermal conversion, low modulus, and high material responsiveness simultaneously. The LiLBot features tunable peak-to-peak amplitudes from 4 to 72 degrees and frequencies from 0.3 to 11 hertz. The oscillation approach offers a strategy for designing autonomous, untethered, and sustainable small-scale soft robots, such as a sailboat, walker, roller, and synchronized flapping wings.
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Affiliation(s)
- Yusen Zhao
- Department of Material Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Qiaofeng Li
- Department of Mechanical and Aerospace Engineering, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Zixiao Liu
- Department of Material Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Yousif Alsaid
- Department of Material Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Pengju Shi
- Department of Material Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Mohammad Khalid Jawed
- Department of Mechanical and Aerospace Engineering, University of California Los Angeles, Los Angeles, CA 90095 USA
| | - Ximin He
- Department of Material Science and Engineering, University of California Los Angeles, Los Angeles, CA 90095 USA
- California Nanosystems Institute, Los Angeles, CA 90095, USA
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23
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Wang T, Joo HJ, Song S, Hu W, Keplinger C, Sitti M. A versatile jellyfish-like robotic platform for effective underwater propulsion and manipulation. SCIENCE ADVANCES 2023; 9:eadg0292. [PMID: 37043565 PMCID: PMC10096580 DOI: 10.1126/sciadv.adg0292] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Accepted: 03/13/2023] [Indexed: 05/27/2023]
Abstract
Underwater devices are critical for environmental applications. However, existing prototypes typically use bulky, noisy actuators and limited configurations. Consequently, they struggle to ensure noise-free and gentle interactions with underwater species when realizing practical functions. Therefore, we developed a jellyfish-like robotic platform enabled by a synergy of electrohydraulic actuators and a hybrid structure of rigid and soft components. Our 16-cm-diameter noise-free prototype could control the fluid flow to propel while manipulating objects to be kept beneath its body without physical contact, thereby enabling safer interactions. Its against-gravity speed was up to 6.1 cm/s, substantially quicker than other examples in literature, while only requiring a low input power of around 100 mW. Moreover, using the platform, we demonstrated contact-based object manipulation, fluidic mixing, shape adaptation, steering, wireless swimming, and cooperation of two to three robots. This study introduces a versatile jellyfish-like robotic platform with a wide range of functions for diverse applications.
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Affiliation(s)
- Tianlu Wang
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany
- Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich 8092, Switzerland
| | - Hyeong-Joon Joo
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany
| | - Shanyuan Song
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany
- Bioinspired Autonomous Miniature Robots Group, Stuttgart 70569, Germany
| | - Wenqi Hu
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany
- Bioinspired Autonomous Miniature Robots Group, Stuttgart 70569, Germany
| | - Christoph Keplinger
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany
- Paul M. Rady Department of Mechanical Engineering, University of Colorado Boulder, Boulder, CO 80309, USA
- Materials Science and Engineering Program, University of Colorado Boulder, Boulder, CO 80309, USA
| | - Metin Sitti
- Physical Intelligence Department, Max Planck Institute for Intelligent Systems, Stuttgart 70569, Germany
- Department of Information Technology and Electrical Engineering, ETH Zurich, Zurich 8092, Switzerland
- School of Medicine and College of Engineering, Koç University, Istanbul 34450, Turkey
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24
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Rumley EH, Preninger D, Shagan Shomron A, Rothemund P, Hartmann F, Baumgartner M, Kellaris N, Stojanovic A, Yoder Z, Karrer B, Keplinger C, Kaltenbrunner M. Biodegradable electrohydraulic actuators for sustainable soft robots. SCIENCE ADVANCES 2023; 9:eadf5551. [PMID: 36947626 PMCID: PMC10032599 DOI: 10.1126/sciadv.adf5551] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/29/2022] [Accepted: 02/22/2023] [Indexed: 06/18/2023]
Abstract
Combating environmental pollution demands a focus on sustainability, in particular from rapidly advancing technologies that are poised to be ubiquitous in modern societies. Among these, soft robotics promises to replace conventional rigid machines for applications requiring adaptability and dexterity. For key components of soft robots, such as soft actuators, it is thus important to explore sustainable options like bioderived and biodegradable materials. We introduce systematically determined compatible materials systems for the creation of fully biodegradable, high-performance electrohydraulic soft actuators, based on various biodegradable polymer films, ester-based liquid dielectric, and NaCl-infused gelatin hydrogel. We demonstrate that these biodegradable actuators reliably operate up to high electric fields of 200 V/μm, show performance comparable to nonbiodegradable counterparts, and survive more than 100,000 actuation cycles. Furthermore, we build a robotic gripper based on biodegradable soft actuators that is readily compatible with commercial robot arms, encouraging wider use of biodegradable materials systems in soft robotics.
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Affiliation(s)
- Ellen H. Rumley
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
- Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, CO, USA
| | - David Preninger
- Division of Soft Matter Physics, Institute for Experimental Physics, Johannes Kepler University, Linz, Austria
- Soft Materials Lab, Linz Institute of Technology, Johannes Kepler University, Linz, Austria
| | - Alona Shagan Shomron
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
| | - Philipp Rothemund
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
- Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, CO, USA
| | - Florian Hartmann
- Division of Soft Matter Physics, Institute for Experimental Physics, Johannes Kepler University, Linz, Austria
- Soft Materials Lab, Linz Institute of Technology, Johannes Kepler University, Linz, Austria
| | - Melanie Baumgartner
- Division of Soft Matter Physics, Institute for Experimental Physics, Johannes Kepler University, Linz, Austria
- Soft Materials Lab, Linz Institute of Technology, Johannes Kepler University, Linz, Austria
| | - Nicholas Kellaris
- Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, CO, USA
- Materials Science and Engineering Program, University of Colorado, Boulder, CO, USA
| | - Andreas Stojanovic
- Division of Soft Matter Physics, Institute for Experimental Physics, Johannes Kepler University, Linz, Austria
- Soft Materials Lab, Linz Institute of Technology, Johannes Kepler University, Linz, Austria
| | - Zachary Yoder
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
| | - Benjamin Karrer
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
- Division of Soft Matter Physics, Institute for Experimental Physics, Johannes Kepler University, Linz, Austria
- Soft Materials Lab, Linz Institute of Technology, Johannes Kepler University, Linz, Austria
| | - Christoph Keplinger
- Robotic Materials Department, Max Planck Institute for Intelligent Systems, Stuttgart, Germany
- Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, CO, USA
- Materials Science and Engineering Program, University of Colorado, Boulder, CO, USA
| | - Martin Kaltenbrunner
- Division of Soft Matter Physics, Institute for Experimental Physics, Johannes Kepler University, Linz, Austria
- Soft Materials Lab, Linz Institute of Technology, Johannes Kepler University, Linz, Austria
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25
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Huang J, Zhang X, Liu R, Ding Y, Guo D. Polyvinyl chloride-based dielectric elastomer with high permittivity and low viscoelasticity for actuation and sensing. Nat Commun 2023; 14:1483. [PMID: 36932099 PMCID: PMC10023783 DOI: 10.1038/s41467-023-37178-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 03/06/2023] [Indexed: 03/19/2023] Open
Abstract
Dielectric elastomers (DEs) are widely used in soft actuation and sensing. Current DE actuators require high driving electrical fields because of their low permittivity. Most of DE actuators and sensors suffer from high viscoelastic effects, leading to high mechanical loss and large shifts of signals. This study demonstrates a valuable strategy to produce polyvinyl chloride (PVC)-based elastomers with high permittivity and low viscoelasticity. The introduction of cyanoethyl cellulose (CEC) into plasticized PVC gel (PVCg) not only confers a high dielectric permittivity (18.9@1 kHz) but also significantly mitigates their viscoelastic effects with a low mechanical loss (0.04@1 Hz). The CEC/PVCg actuators demonstrate higher actuation performances over the existing DE actuators under low electrical fields and show marginal displacement shifts (7.78%) compared to VHB 4910 (136.09%). The CEC/PVCg sensors display high sensitivity, fast response, and limited signal drifts, enabling their faithful monitoring of multiple human motions.
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Affiliation(s)
- Jianjian Huang
- State Laboratory of Surface & Interface, Zhengzhou University of Light Industry, Zhengzhou, 450002, China
| | - Xiaodie Zhang
- State Laboratory of Surface & Interface, Zhengzhou University of Light Industry, Zhengzhou, 450002, China
| | - Ruixue Liu
- State Laboratory of Surface & Interface, Zhengzhou University of Light Industry, Zhengzhou, 450002, China
| | - Yonghui Ding
- Center for Advanced Regenerative Engineering, Department of Biomedical Engineering, Northwestern University, Evanston, IL, 60208, USA.
| | - Dongjie Guo
- State Laboratory of Surface & Interface, Zhengzhou University of Light Industry, Zhengzhou, 450002, China.
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26
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Yang J, Zhang H, Berdin A, Hu W, Zeng H. Dandelion-Inspired, Wind-Dispersed Polymer-Assembly Controlled by Light. ADVANCED SCIENCE (WEINHEIM, BADEN-WURTTEMBERG, GERMANY) 2023; 10:e2206752. [PMID: 36574479 PMCID: PMC9982548 DOI: 10.1002/advs.202206752] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/08/2022] [Indexed: 06/01/2023]
Abstract
The rise of stimuli-responsive polymers has brought about a wealth of materials for small-scale, wirelessly controlled soft-bodied robots. Thinking beyond conventional robotic mobilities already demonstrated in synthetic systems, such as walking, swimming and jumping, flying in air by dispersal, gliding, or even hovering is a frontier yet to be explored by responsive materials. The demanding requirements for actuator's performance, lightweight, and effective aerodynamic design underlie the grand challenges. Here, a soft matter-based porous structure capable of wind-assisted dispersal and lift-off/landing action under the control of a light beam is reported. The design is inspired by the seed of dandelion, resembling several biomimetic features, i.e., high porosity, lightweight, and separated vortex ring generation under a steady wind flow. Superior to its natural counterparts, this artificial seed is equipped with a soft actuator made of light-responsive liquid crystalline elastomer, which induces reversible opening/closing actions of the bristles upon visible light excitation. This shape-morphing enables manual tuning of terminal velocity, drag coefficient, and wind threshold for dispersal. Optically controlled wind-assisted lift-off and landing actions, and a light-induced local accumulation in descending structures are demonstrated. The results offer novel approaches for wirelessly controlled, miniatured devices that can passively navigate over a large aerial space.
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Affiliation(s)
- Jianfeng Yang
- Faculty of Engineering and Natural SciencesTampere UniversityP.O. Box 541TampereFI‐33101Finland
| | - Hang Zhang
- Department of Applied PhysicsAalto UniversityP.O. Box 15100EspooFI‐02150Finland
| | - Alex Berdin
- Faculty of Engineering and Natural SciencesTampere UniversityP.O. Box 541TampereFI‐33101Finland
| | - Wenqi Hu
- Max Planck Institute for Intelligent Systems, Stuttgart70569StuttgartGermany
| | - Hao Zeng
- Faculty of Engineering and Natural SciencesTampere UniversityP.O. Box 541TampereFI‐33101Finland
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27
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Liang H, Wu Y, Zhang Y, Chen E, Wei Y, Ji Y. Elastomers Grow into Actuators. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2023; 35:e2209853. [PMID: 36604968 DOI: 10.1002/adma.202209853] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 12/28/2022] [Indexed: 06/17/2023]
Abstract
It is common knowledge that when an elastomer (rubber) is stretched, its length will be maintained if its two ends are fixed. Here, it is serendipitously found that when an elastomer is slowly elongated further to achieve buckling under such conditions, the final length is much longer than the pre-stretched length. This allows the design of untethered autonomous synthetic-material-based soft robots that do not need any other chemical or electrical energy sources or external stimuli after the pre-strain is installed. Once the growth starts, the elongation continues to proceed even when the applied force is removed. Moreover, the elastomer, after growing, eventually forms a robust soft actuator that can be reshaped for different purposes. Few synthetic materials can grow like this, so far. This investigation shows that the material has an uncommon liquid crystal phase. Contrary to normal liquid crystals, it becomes birefringent only at high temperatures. The formation and the reshaping of the resulting soft actuators relate to a usually unnoticed reversible reaction. The work is promising to promote further understanding of dynamic covalent chemistry and liquid crystal elastomers, as well as to foster new designs and high-impact applications of bioinspired sustainable soft actuators in areas other than soft robots.
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Affiliation(s)
- Huan Liang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yahe Wu
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Yubai Zhang
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Erqiang Chen
- Beijing National Laboratory for Molecular Sciences, Key Laboratory of Polymer Chemistry and Physics of Ministry of Education, Center for Soft Matter Science and Engineering, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China
| | - Yen Wei
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
- Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung-Yuan Christian University, Chung-Li, Taiwan, 32023, China
| | - Yan Ji
- The Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
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28
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Zhang S, Ke X, Jiang Q, Chai Z, Wu Z, Ding H. Fabrication and Functionality Integration Technologies for Small-Scale Soft Robots. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2022; 34:e2200671. [PMID: 35732070 DOI: 10.1002/adma.202200671] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 06/12/2022] [Indexed: 06/15/2023]
Abstract
Small-scale soft robots are attracting increasing interest for visible and potential applications owing to their safety and tolerance resulting from their intrinsic soft bodies or compliant structures. However, it is not sufficient that the soft bodies merely provide support or system protection. More importantly, to meet the increasing demands of controllable operation and real-time feedback in unstructured/complicated scenarios, these robots are required to perform simplex and multimodal functionalities for sensing, communicating, and interacting with external environments during large or dynamic deformation with the risk of mismatch or delamination. Challenges are encountered during fabrication and integration, including the selection and fabrication of composite/materials and structures, integration of active/passive functional modules with robust interfaces, particularly with highly deformable soft/stretchable bodies. Here, methods and strategies of fabricating structural soft bodies and integrating them with functional modules for developing small-scale soft robots are investigated. Utilizing templating, 3D printing, transfer printing, and swelling, small-scale soft robots can be endowed with several perceptual capabilities corresponding to diverse stimulus, such as light, heat, magnetism, and force. The integration of sensing and functionalities effectively enhances the agility, adaptability, and universality of soft robots when applied in various fields, including smart manufacturing, medical surgery, biomimetics, and other interdisciplinary sciences.
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Affiliation(s)
- Shuo Zhang
- State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Xingxing Ke
- State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Qin Jiang
- State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Zhiping Chai
- State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Zhigang Wu
- State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
| | - Han Ding
- State Key Laboratory of Digital Manufacturing Equipment and Technology, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, 430074, P. R. China
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29
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Schara M, Zeng M, Jumet B, Preston DJ. A low-cost wearable device for portable sequential compression therapy. Front Robot AI 2022; 9:1012862. [DOI: 10.3389/frobt.2022.1012862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Accepted: 10/25/2022] [Indexed: 11/16/2022] Open
Abstract
In 2020, cardiovascular diseases resulted in 25% of unnatural deaths in the United States. Treatment with long-term administration of medication can adversely affect other organs, and surgeries such as coronary artery grafts are risky. Meanwhile, sequential compression therapy (SCT) offers a low-risk alternative, but is currently expensive and unwieldy, and often requires the patient to be immobilized during administration. Here, we present a low-cost wearable device to administer SCT, constructed using a stacked lamination fabrication approach. Expanding on concepts from the field of soft robotics, textile sheets are thermally bonded to form pneumatic actuators, which are controlled by an inconspicuous and tetherless electronic onboard supply of pressurized air. Our open-source, low-profile, and lightweight (140 g) device costs $62, less than one-third the cost the least expensive alternative and one-half the weight of lightest alternative approved by the US Food and Drug Administration (FDA), presenting the opportunity to more effectively provide SCT to socioeconomically disadvantaged individuals. Furthermore, our textile-stacking method, inspired by conventional fabrication methods from the apparel industry, along with the lightweight fabrics used, allows the device to be worn more comfortably than other SCT devices. By reducing physical and financial encumbrances, the device presented in this work may better enable patients to treat cardiovascular diseases and aid in recovery from cardiac surgeries.
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30
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Yan B. Actuators for Implantable Devices: A Broad View. MICROMACHINES 2022; 13:1756. [PMID: 36296109 PMCID: PMC9610948 DOI: 10.3390/mi13101756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/12/2022] [Accepted: 10/06/2022] [Indexed: 06/16/2023]
Abstract
The choice of actuators dictates how an implantable biomedical device moves. Specifically, the concept of implantable robots consists of the three pillars: actuators, sensors, and powering. Robotic devices that require active motion are driven by a biocompatible actuator. Depending on the actuating mechanism, different types of actuators vary remarkably in strain/stress output, frequency, power consumption, and durability. Most reviews to date focus on specific type of actuating mechanism (electric, photonic, electrothermal, etc.) for biomedical applications. With a rapidly expanding library of novel actuators, however, the granular boundaries between subcategories turns the selection of actuators a laborious task, which can be particularly time-consuming to those unfamiliar with actuation. To offer a broad view, this study (1) showcases the recent advances in various types of actuating technologies that can be potentially implemented in vivo, (2) outlines technical advantages and the limitations of each type, and (3) provides use-specific suggestions on actuator choice for applications such as drug delivery, cardiovascular, and endoscopy implants.
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Affiliation(s)
- Bingxi Yan
- Department of Electrical and Computer Engineering, Ohio State University, Columbus, OH 43210, USA
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31
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Abstract
In soft devices, complex actuation sequences and precise force control typically require hard electronic valves and microcontrollers. Existing designs for entirely soft pneumatic control systems are capable of either digital or analog operation, but not both, and are limited by speed of actuation, range of pressure, time required for fabrication, or loss of power through pull-down resistors. Using the nonlinear mechanics intrinsic to structures composed of soft materials-in this case, by leveraging membrane inversion and tube kinking-two modular soft components are developed: a piston actuator and a bistable pneumatic switch. These two components combine to create valves capable of analog pressure regulation, simplified digital logic, controlled oscillation, nonvolatile memory storage, linear actuation, and interfacing with human users in both digital and analog formats. Three demonstrations showcase the capabilities of systems constructed from these valves: 1) a wearable glove capable of analog control of a soft artificial robotic hand based on input from a human user's fingers, 2) a human-controlled cushion matrix designed for use in medical care, and 3) an untethered robot which travels a distance dynamically programmed at the time of operation to retrieve an object. This work illustrates pathways for complementary digital and analog control of soft robots using a unified valve design.
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32
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Xu Z, Li R, Li H, Gao G, Chen T. Flexible and adhesive liquid-free ionic conductive elastomers toward human-machine interaction. SOFT MATTER 2022; 18:7103-7111. [PMID: 36082742 DOI: 10.1039/d2sm00865c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Based on the demand for flexible human-machine interaction devices, it is urgent to develop high-performance stretchable ionic conductive materials. However, most gel-based ionic conductive materials are composed of crosslinked polymer networks that contain liquids, and suffer from limitations of solvent volatilization and leakage, and the cross-linking restricts the movement and diffusion of polymer chains, making it difficult for them to achieve adhesion. Here, we introduce flexible and adhesive liquid-free ionic conductive elastomers (ICE) with salt using a non-crosslinked polymer strategy. The ICE show a transparency of 89.5%, Tg of -51.2 °C, negligible weight loss at 200 °C, a tensile fracture strain of 289.5%, and an initial modulus of 45.7 kPa, and is adhesive to various solid surfaces with an interfacial toughness of 11.4 to 41.4 J m-2. Moreover, the ICE exhibit stable electrical conductivity under ambient conditions. Triboelectric nanogenerators (TENGs) were assembled on an electrical shell surface with the adhesive ICE as an electrostatic induction layer and were displayed for use as human-machine interactive keyboards. This approach opens a route to making adhesive and stable polymer ionic conductors for human-machine interaction.
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Affiliation(s)
- Zhenyu Xu
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rui Li
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
| | - Huijing Li
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Guorong Gao
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tao Chen
- Key Laboratory of Marine Materials and Related Technologies, Zhejiang Key Laboratory of Marine Materials and Protective Technologies, Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China.
- School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
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33
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Liu H, Sun Z, Chen Y, Zhang W, Chen X, Wong CP. Laser Processing of Flexible In-Plane Micro-supercapacitors: Progresses in Advanced Manufacturing of Nanostructured Electrodes. ACS NANO 2022; 16:10088-10129. [PMID: 35786945 DOI: 10.1021/acsnano.2c02812] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Flexible in-plane architecture micro-supercapacitors (MSCs) are competitive candidates for on-chip miniature energy storage applications owing to their light weight, small size, high flexibility, as well as the advantages of short charging time, high power density, and long cycle life. However, tedious and time-consuming processes are required for the manufacturing of high-resolution interdigital electrodes using conventional approaches. In contrast, the laser processing technique enables high-efficiency high-precision patterning and advanced manufacturing of nanostructured electrodes. In this review, the recent advances in laser manufacturing and patterning of nanostructured electrodes for applications in flexible in-plane MSCs are comprehensively summarized. Various laser processing techniques for the synthesis, modification, and processing of interdigital electrode materials, including laser pyrolysis, reduction, oxidation, growth, activation, sintering, doping, and ablation, are discussed. In particular, some special features and merits of laser processing techniques are highlighted, including the impacts of laser types and parameters on manufacturing electrodes with desired morphologies/structures and their applications on the formation of high-quality nanoshaped graphene, the selective deposition of nanostructured materials, the controllable nanopore etching and heteroatom doping, and the efficient sintering of nanometal products. Finally, the current challenges and prospects associated with the laser processing of in-plane MSCs are also discussed. This review will provide a useful guidance for the advanced manufacturing of nanostructured electrodes in flexible in-plane energy storage devices and beyond.
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Affiliation(s)
- Huilong Liu
- State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment & School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China
- Center of Super-Diamond and Advanced Films (COSDAF) & Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Zhijian Sun
- School of Materials Science and Engineering, Georgia Institute of Technology, 711 Ferst Drive, Atlanta, Georgia 30332, United States
| | - Yun Chen
- State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment & School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Wenjun Zhang
- Center of Super-Diamond and Advanced Films (COSDAF) & Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Xin Chen
- State Key Laboratory of Precision Electronic Manufacturing Technology and Equipment & School of Electromechanical Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Ching-Ping Wong
- School of Materials Science and Engineering, Georgia Institute of Technology, 711 Ferst Drive, Atlanta, Georgia 30332, United States
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Dong Y, Wang L, Xia N, Yang Z, Zhang C, Pan C, Jin D, Zhang J, Majidi C, Zhang L. Untethered small-scale magnetic soft robot with programmable magnetization and integrated multifunctional modules. SCIENCE ADVANCES 2022; 8:eabn8932. [PMID: 35731876 PMCID: PMC9217092 DOI: 10.1126/sciadv.abn8932] [Citation(s) in RCA: 51] [Impact Index Per Article: 25.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Intelligent magnetic soft robots capable of programmable structural changes and multifunctionality modalities depend on material architectures and methods for controlling magnetization profiles. While some efforts have been made, there are still key challenges in achieving programmable magnetization profile and creating heterogeneous architectures. Here, we directly embed programmed magnetization patterns (magnetization modules) into the adhesive sticker layers to construct soft robots with programmable magnetization profiles and geometries and then integrate spatially distributed functional modules. Functional modules including temperature and ultraviolet light sensing particles, pH sensing sheets, oil sensing foams, positioning electronic component, circuit foils, and therapy patch films are integrated into soft robots. These test beds are used to explore multimodal robot locomotion and various applications related to environmental sensing and detection, circuit repairing, and gastric ulcer coating, respectively. This proposed approach to engineering modular soft material systems has the potential to expand the functionality, versatility, and adaptability of soft robots.
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Affiliation(s)
- Yue Dong
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Lu Wang
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Neng Xia
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Zhengxin Yang
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Chong Zhang
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Chengfeng Pan
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Dongdong Jin
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
| | - Jiachen Zhang
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong SAR, China
| | - Carmel Majidi
- Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, PA 15213, USA
- Corresponding author. (L.Z.); (C.M.)
| | - Li Zhang
- Department of Mechanical and Automation Engineering, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
- Department of Surgery, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
- T Stone Robotics Institute, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong SAR, China
- Corresponding author. (L.Z.); (C.M.)
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Supramolecular nylon-based actuators with a high work efficiency based on host–guest complexation and the mechanoisomerization of azobenzene. Polym J 2022. [DOI: 10.1038/s41428-022-00666-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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