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Mohammadi Nejad Rashty A, Sharbafi MA, Mohseni O, Seyfarth A. Role of compliant mechanics and motor control in hopping - from human to robot. Sci Rep 2024; 14:6820. [PMID: 38514699 PMCID: PMC10957903 DOI: 10.1038/s41598-024-57149-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2023] [Accepted: 03/14/2024] [Indexed: 03/23/2024] Open
Abstract
Compliant leg function found during bouncy gaits in humans and animals can be considered a role model for designing and controlling bioinspired robots and assistive devices. The human musculoskeletal design and control differ from distal to proximal joints in the leg. The specific mechanical properties of different leg parts could simplify motor control, e.g., by taking advantage of passive body dynamics. This control embodiment is complemented by neural reflex circuitries shaping human motor control. This study investigates the contribution of specific passive and active properties at different leg joint levels in human hopping at different hopping frequencies. We analyze the kinematics and kinetics of human leg joints to design and control a bioinspired hopping robot. In addition, this robot is used as a test rig to validate the identified concepts from human hopping. We found that the more distal the joint, the higher the possibility of benefit from passive compliant leg structures. A passive elastic element nicely describes the ankle joint function. In contrast, a more significant contribution to energy management using an active element (e.g., by feedback control) is predicted for the knee and hip joints. The ankle and knee joints are the key contributors to adjusting hopping frequency. Humans can speed up hopping by increasing ankle stiffness and tuning corresponding knee control parameters. We found that the force-modulated compliance (FMC) as an abstract reflex-based control beside a fixed spring can predict human knee torque-angle patterns at different frequencies. These developed bioinspired models for ankle and knee joints were applied to design and control the EPA-hopper-II robot. The experimental results support our biomechanical findings while indicating potential robot improvements. Based on the proposed model and the robot's experimental results, passive compliant elements (e.g. tendons) have a larger capacity to contribute to the distal joint function compared to proximal joints. With the use of more compliant elements in the distal joint, a larger contribution to managing energy changes is observed in the upper joints.
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Affiliation(s)
- Aida Mohammadi Nejad Rashty
- Lauflabor Locomotion Laboratory, Institute of Sport Science and Centre for Cognitive Science, Technical University of Darmstadt, Darmstadt, 64289, Germany.
| | - Maziar A Sharbafi
- Lauflabor Locomotion Laboratory, Institute of Sport Science and Centre for Cognitive Science, Technical University of Darmstadt, Darmstadt, 64289, Germany
| | - Omid Mohseni
- Lauflabor Locomotion Laboratory, Institute of Sport Science and Centre for Cognitive Science, Technical University of Darmstadt, Darmstadt, 64289, Germany
| | - André Seyfarth
- Lauflabor Locomotion Laboratory, Institute of Sport Science and Centre for Cognitive Science, Technical University of Darmstadt, Darmstadt, 64289, Germany
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Brown C, Simonsick E, Schrack J, Ferrucci L. Impact of balance on the energetic cost of walking and gait speed. J Am Geriatr Soc 2023; 71:3489-3497. [PMID: 37528742 DOI: 10.1111/jgs.18521] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 06/07/2023] [Accepted: 06/25/2023] [Indexed: 08/03/2023]
Abstract
BACKGROUND Examine the relationship between balance test performance and the energetic cost of walking (ECW) and gait speed. METHODS Cross-sectional and longitudinal analyses of data from the Baltimore Longitudinal Study of Aging. Men (48%) and women aged 60-96 years enrolled in the BLSA between 2007 and 2020 (n = 1132). Balance was assessed using narrow walk (NW) and progressive standing balance tests (SB). ECW measured during 2.5-min usual paced walk while participants wore a portable indirect calorimeter. Gait speed assessed over 6-m. Each test parameterized using validated methods. Statistical analysis to compare balance measures to ECW, and gait speed used generalized logistic regression models and adjustments for age, sex, race, height, weight, and comorbidities. RESULTS Cross-sectionally, mean ECW was higher and gait speed slower in persons who failed the NW than those who passed (0.189 vs. 0.164 mL/kg/m, p < 0.0001 and 0.96 vs. 1.15 m/s, p < 0.0001, respectively). Mean ECW was increasingly higher and gait speed slower over three progressively challenging SB tests (0.207 vs. 0.171 vs. 0.164 mL/kg/m, p < 0.0001 and 0.95 vs. 1.05 vs. 1.15 m/s, p < 0.0001). Over an average 2.4 years, those who declined in SB and NW had a higher ECW and slower gait speed than persons who maintained performance (SB: 0.18 vs. 0.160 mL/kg/m, p = 0.0003, and 1.00 vs. 1.13 m/s, p = <0.001; NW: 0.175 vs. 0.160 mL/kg/m, p = 0.002, and 1.04 vs. 1.14 m/s, p = 0.001). Persons who improved had lower ECW and faster gait speed than those who failed at both visits (SB: 0.169 vs. 0.240 mL/kg/m, p = 0.0002, and 0.99 vs. 0.94 m/s, p = 0.67, NW: 0.163 vs. 0.195 mL/kg/m, p = 0.0005, and 1.10 vs. 0.92 m/s, p < 0.001). CONCLUSION Instability contributes to higher ECW and slower gait speed which suggests that rehabilitation efforts to improve balance may help maintain function further into older adulthood and delay mobility limitation.
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Affiliation(s)
- Colleen Brown
- College of Public Health, Temple University, Philidelphia, PA, USA
| | - Eleanor Simonsick
- Intramural Research Program, National Institute on Aging (NIH/NIA), Baltimore, MD, USA
| | - Jennifer Schrack
- Bloomberg School of Public Health, Johns Hopkins University, Baltimore, MD, USA
| | - Luigi Ferrucci
- Intramural Research Program, National Institute on Aging (NIH/NIA), Baltimore, MD, USA
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Vielemeyer J, Schreff L, Hochstein S, Müller R. Virtual pivot point: Always experimentally observed in human walking? PLoS One 2023; 18:e0292874. [PMID: 37831656 PMCID: PMC10575527 DOI: 10.1371/journal.pone.0292874] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 10/01/2023] [Indexed: 10/15/2023] Open
Abstract
A main challenge in human walking is maintaining stability. One strategy to balance the whole body dynamically is to direct the ground reaction forces toward a point above the center of mass, called virtual pivot point (VPP). This strategy could be observed in various experimental studies for human and animal gait. A VPP was also observed when VPP input variables like center of mass or ground reaction forces were perturbed. In this study, the kinetic and kinematic consequences of a center of pressure manipulation and the influence on the VPP are investigated. Thus, eleven participants walked with manipulated center of pressure (i.e. barefoot, backwards, with a rigid sole, with stilts, and in handstand compared to shoe walking). In all conditions a VPP could be observed, only one participant showed no VPP in handstand walking. The vertical VPP position only differs between shoe walking and rigid sole walking, there are no significant differences between the conditions in the horizontal VPP position and the spread around the VPP. However, it is conceivable that for more severe gait changes, walking without VPP could be observed. To further analyze this issue, the authors provide a VPP calculation tool for testing data regarding the existence of the VPP.
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Affiliation(s)
- Johanna Vielemeyer
- Institute of Sport Sciences, Friedrich-Schiller-University Jena, Jena, Germany
- GaitLab, Klinikum Bayreuth GmbH, Bayreuth, Germany
| | - Lucas Schreff
- GaitLab, Klinikum Bayreuth GmbH, Bayreuth, Germany
- Bayreuth Center of Sport Science, University of Bayreuth, Bayreuth, Germany
| | - Stefan Hochstein
- Institute of Sport Sciences, Martin-Luther-University Halle-Wittenberg, Halle, Germany
| | - Roy Müller
- GaitLab, Klinikum Bayreuth GmbH, Bayreuth, Germany
- Bayreuth Center of Sport Science, University of Bayreuth, Bayreuth, Germany
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Domínguez-Ruiz A, López-Caudana EO, Lugo-González E, Espinosa-García FJ, Ambrocio-Delgado R, García UD, López-Gutiérrez R, Alfaro-Ponce M, Ponce P. Low limb prostheses and complex human prosthetic interaction: A systematic literature review. Front Robot AI 2023; 10:1032748. [PMID: 36860557 PMCID: PMC9968924 DOI: 10.3389/frobt.2023.1032748] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2022] [Accepted: 01/11/2023] [Indexed: 02/15/2023] Open
Abstract
A few years ago, powered prostheses triggered new technological advances in diverse areas such as mobility, comfort, and design, which have been essential to improving the quality of life of individuals with lower limb disability. The human body is a complex system involving mental and physical health, meaning a dependant relationship between its organs and lifestyle. The elements used in the design of these prostheses are critical and related to lower limb amputation level, user morphology and human-prosthetic interaction. Hence, several technologies have been employed to accomplish the end user's needs, for example, advanced materials, control systems, electronics, energy management, signal processing, and artificial intelligence. This paper presents a systematic literature review on such technologies, to identify the latest advances, challenges, and opportunities in developing lower limb prostheses with the analysis on the most significant papers. Powered prostheses for walking in different terrains were illustrated and examined, with the kind of movement the device should perform by considering the electronics, automatic control, and energy efficiency. Results show a lack of a specific and generalised structure to be followed by new developments, gaps in energy management and improved smoother patient interaction. Additionally, Human Prosthetic Interaction (HPI) is a term introduced in this paper since no other research has integrated this interaction in communication between the artificial limb and the end-user. The main goal of this paper is to provide, with the found evidence, a set of steps and components to be followed by new researchers and experts looking to improve knowledge in this field.
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Affiliation(s)
- Adan Domínguez-Ruiz
- Institute for the Future of Education, Tecnologico de Monterrey, Mexico City, México
| | | | - Esther Lugo-González
- Instituto de Electrónica y Mecatrónica, Universidad Tecnológica de la Mixteca, Huajuapan de León, Oaxaca, México
| | | | - Rocío Ambrocio-Delgado
- División de Estudios de Posgrado, Universidad Tecnológica de la Mixteca, Huajuapan de León, Oaxaca, México
| | - Ulises D. García
- CONACYT-CINVESTAV, Av. Instituto Politécnico Nacional 2508, col. San Pedro Zacatenco, Ciudad deMéxico, México
| | - Ricardo López-Gutiérrez
- CONACYT-CINVESTAV, Av. Instituto Politécnico Nacional 2508, col. San Pedro Zacatenco, Ciudad deMéxico, México
| | - Mariel Alfaro-Ponce
- Institute of Advanced Materials for Sustainable Manufacturing, Tecnologico de Monterrey, Mexico City, México
| | - Pedro Ponce
- Institute of Advanced Materials for Sustainable Manufacturing, Tecnologico de Monterrey, Mexico City, México,*Correspondence: Pedro Ponce,
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Mohseni O, Schmidt P, Seyfarth A, Sharbafi MA. Unified GRF-based control for adjusting hopping frequency with various robot configurations. Adv Robot 2022. [DOI: 10.1080/01691864.2022.2077637] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
Affiliation(s)
- Omid Mohseni
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, TU Darmstadt, Darmstadt, Germany
| | - Patrick Schmidt
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, TU Darmstadt, Darmstadt, Germany
| | - Andre Seyfarth
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, TU Darmstadt, Darmstadt, Germany
| | - Maziar A. Sharbafi
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, TU Darmstadt, Darmstadt, Germany
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Bayón C, Keemink AQL, van Mierlo M, Rampeltshammer W, van der Kooij H, van Asseldonk EHF. Cooperative ankle-exoskeleton control can reduce effort to recover balance after unexpected disturbances during walking. J Neuroeng Rehabil 2022; 19:21. [PMID: 35172846 PMCID: PMC8851842 DOI: 10.1186/s12984-022-01000-y] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 02/02/2022] [Indexed: 11/10/2022] Open
Abstract
Background In the last two decades, lower-limb exoskeletons have been developed to assist human standing and locomotion. One of the ongoing challenges is the cooperation between the exoskeleton balance support and the wearer control. Here we present a cooperative ankle-exoskeleton control strategy to assist in balance recovery after unexpected disturbances during walking, which is inspired on human balance responses. Methods We evaluated the novel controller in ten able-bodied participants wearing the ankle modules of the Symbitron exoskeleton. During walking, participants received unexpected forward pushes with different timing and magnitude at the pelvis level, while being supported (Exo-Assistance) or not (Exo-NoAssistance) by the robotic assistance provided by the controller. The effectiveness of the assistive strategy was assessed in terms of (1) controller performance (Detection Delay, Joint Angles, and Exerted Ankle Torques), (2) analysis of effort (integral of normalized Muscle Activity after perturbation onset); and (3) Analysis of center of mass COM kinematics (relative maximum COM Motion, Recovery Time and Margin of Stability) and spatio-temporal parameters (Step Length and Swing Time). Results In general, the results show that when the controller was active, it was able to reduce participants’ effort while keeping similar ability to counteract and withstand the balance disturbances. Significant reductions were found for soleus and gastrocnemius medialis activity of the stance leg when comparing Exo-Assistance and Exo-NoAssistance walking conditions. Conclusions The proposed controller was able to cooperate with the able-bodied participants in counteracting perturbations, contributing to the state-of-the-art of bio-inspired cooperative ankle exoskeleton controllers for supporting dynamic balance. In the future, this control strategy may be used in exoskeletons to support and improve balance control in users with motor disabilities. Supplementary Information The online version contains supplementary material available at 10.1186/s12984-022-01000-y.
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Affiliation(s)
- Cristina Bayón
- Department of Biomechanical Engineering, University of Twente, Enschede, The Netherlands.
| | - Arvid Q L Keemink
- Department of Biomechanical Engineering, University of Twente, Enschede, The Netherlands
| | - Michelle van Mierlo
- Department of Biomechanical Engineering, University of Twente, Enschede, The Netherlands
| | | | - Herman van der Kooij
- Department of Biomechanical Engineering, University of Twente, Enschede, The Netherlands.,Department of BioMechanical Engineering, Delft University of Technology, Delft, The Netherlands
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Firouzi V, Bahrami F, Sharbafi MA. Human balance control in 3D running based on virtual pivot point concept. J Exp Biol 2022; 225:274032. [PMID: 35040960 DOI: 10.1242/jeb.243080] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 01/04/2022] [Indexed: 11/20/2022]
Abstract
Balance control is one of the crucial challenges in bipedal locomotion. Humans need to maintain their trunk upright while the body behaves like an inverted pendulum which is inherently unstable. Instead, the virtual pivot point (VPP) concept introduced a new virtual pendulum model to the human balance control paradigm by analyzing the ground reaction forces (GRF) in the body coordinate frame. This paper presents novel VPP-based analyses of the postural stability of human running in a 3D space. We demonstrate the relation between the VPP position and the gait speed. The experimental results suggest different control strategies in frontal and sagittal planes. The ground reaction forces intersect below the center of mass in the sagittal plane and above the center of mass in the frontal plane. These VPP locations are found for the sagittal and frontal planes at all running speeds, respectively. We introduced a 3D VPP-based model which can replicate the kinematic and kinetic behavior of human running. The similarity between the experimental and simulation results indicates the ability of the VPP concept in predicting human balance control in running and can support its applicability for gait assistance.
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Affiliation(s)
- Vahid Firouzi
- Electrical and Computer Engineering Department, College of Engineering, University of Tehran, Tehran, Iran
| | - Fariba Bahrami
- Electrical and Computer Engineering Department, College of Engineering, University of Tehran, Tehran, Iran
| | - Maziar A Sharbafi
- Lauflabor Laboratory, Technische Universität Darmstadt, Darmstadt, Germany
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Bayón C, Delgado-Oleas G, Avellar L, Bentivoglio F, Di Tommaso F, Tagliamonte NL, Rocon E, van Asseldonk EHF. Development and Evaluation of BenchBalance: A System for Benchmarking Balance Capabilities of Wearable Robots and Their Users. SENSORS (BASEL, SWITZERLAND) 2021; 22:119. [PMID: 35009661 PMCID: PMC8747156 DOI: 10.3390/s22010119] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2021] [Revised: 12/21/2021] [Accepted: 12/22/2021] [Indexed: 11/16/2022]
Abstract
Recent advances in the control of overground exoskeletons are being centered on improving balance support and decreasing the reliance on crutches. However, appropriate methods to quantify the stability of these exoskeletons (and their users) are still under development. A reliable and reproducible balance assessment is critical to enrich exoskeletons' performance and their interaction with humans. In this work, we present the BenchBalance system, which is a benchmarking solution to conduct reproducible balance assessments of exoskeletons and their users. Integrating two key elements, i.e., a hand-held perturbator and a smart garment, BenchBalance is a portable and low-cost system that provides a quantitative assessment related to the reaction and capacity of wearable exoskeletons and their users to respond to controlled external perturbations. A software interface is used to guide the experimenter throughout a predefined protocol of measurable perturbations, taking into account antero-posterior and mediolateral responses. In total, the protocol is composed of sixteen perturbation conditions, which vary in magnitude and location while still controlling their orientation. The data acquired by the interface are classified and saved for a subsequent analysis based on synthetic metrics. In this paper, we present a proof of principle of the BenchBalance system with a healthy user in two scenarios: subject not wearing and subject wearing the H2 lower-limb exoskeleton. After a brief training period, the experimenter was able to provide the manual perturbations of the protocol in a consistent and reproducible way. The balance metrics defined within the BenchBalance framework were able to detect differences in performance depending on the perturbation magnitude, location, and the presence or not of the exoskeleton. The BenchBalance system will be integrated at EUROBENCH facilities to benchmark the balance capabilities of wearable exoskeletons and their users.
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Affiliation(s)
- Cristina Bayón
- Department of Biomechanical Engineering, University of Twente, 7522 NB Enschede, The Netherlands;
- Centro de Automática y Robótica, Universidad Politécnica de Madrid, 28500 Madrid, Spain; (G.D.-O.); (L.A.); (E.R.)
| | - Gabriel Delgado-Oleas
- Centro de Automática y Robótica, Universidad Politécnica de Madrid, 28500 Madrid, Spain; (G.D.-O.); (L.A.); (E.R.)
| | - Leticia Avellar
- Centro de Automática y Robótica, Universidad Politécnica de Madrid, 28500 Madrid, Spain; (G.D.-O.); (L.A.); (E.R.)
| | | | - Francesco Di Tommaso
- Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.B.); (F.D.T.); (N.L.T.)
| | - Nevio L. Tagliamonte
- Università Campus Bio-Medico di Roma, 00128 Rome, Italy; (F.B.); (F.D.T.); (N.L.T.)
- Fondazione Santa Lucia, 00179 Rome, Italy
| | - Eduardo Rocon
- Centro de Automática y Robótica, Universidad Politécnica de Madrid, 28500 Madrid, Spain; (G.D.-O.); (L.A.); (E.R.)
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Zhao G, Grimmer M, Seyfarth A. The mechanisms and mechanical energy of human gait initiation from the lower-limb joint level perspective. Sci Rep 2021; 11:22473. [PMID: 34795327 PMCID: PMC8602421 DOI: 10.1038/s41598-021-01694-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 11/02/2021] [Indexed: 11/09/2022] Open
Abstract
This study aims to improve our understanding of gait initiation mechanisms and the lower-limb joint mechanical energy contributions. Healthy subjects were instructed to initiate gait on an instrumented track to reach three self-selected target velocities: slow, normal and fast. Lower-limb joint kinematics and kinetics of the first five strides were analyzed. The results show that the initial lateral weight shift is achieved by hip abduction torque on the lifting leg (leading limb). Before the take-off of the leading limb, the forward body movement is initiated by decreasing ankle plantarflexion torque, which results in an inverted pendulum-like passive forward fall. The hip flexion/extension joint has the greatest positive mechanical energy output in the first stride of the leading limb, while the ankle joint contributes the most positive mechanical energy in the first stride of the trailing limb (stance leg). Our results indicate a strong correlation between control of the frontal plane and the sagittal plane joints during gait initiation. The identified mechanisms and the related data can be used as a guideline for improving gait initiation with wearable robots such as exoskeletons and prostheses.
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Affiliation(s)
- Guoping Zhao
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, Technical University of Darmstadt, 64289, Darmstadt, Germany.
| | - Martin Grimmer
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, Technical University of Darmstadt, 64289, Darmstadt, Germany
| | - Andre Seyfarth
- Lauflabor Locomotion Laboratory, Centre for Cognitive Science, Technical University of Darmstadt, 64289, Darmstadt, Germany
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Firouzi V, Davoodi A, Bahrami F, Sharbafi MA. From a biological template model to gait assistance with an exosuit. BIOINSPIRATION & BIOMIMETICS 2021; 16:066024. [PMID: 34624880 DOI: 10.1088/1748-3190/ac2e0d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2021] [Accepted: 10/08/2021] [Indexed: 06/13/2023]
Abstract
The invention of soft wearable assistive devices, known as exosuits, introduced a new aspect in assisting unimpaired subjects. In this study, we designed and developed an exosuit with compliant biarticular thigh actuators called BATEX. Unlike the conventional method of using rigid actuators in exosuits, the BATEX is made of serial elastic actuators (SEA) resembling artificial muscles. This bioinspired design is complemented by the novel control concept of using the ground reaction force to adjust the artificial muscles' stiffness in the stance phase. By locking the motors in the swing phase, the SEAs will be simplified to passive biarticular springs, which is sufficient for leg swinging. The key concept in our design and control approach is to synthesize human locomotion to develop an assistive device instead of copying human motor control outputs. Analyzing human walking assistance using experiment-based OpenSim simulations demonstrates the advantages of the proposed design and control of BATEX, such as 9.4% reduction in metabolic cost during normal walking condition. This metabolic reduction increases to 10.4% when the subjects carry a 38 kg load. The adaptability of our proposed model-based control to such an unknown condition outperforms the assistance level of the model-free optimal controller. Moreover, increasing the assistive system's efficiency by adjusting the actuator compliance with the force feedback supports our previous findings on the LOPES II exoskeleton.
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Affiliation(s)
- Vahid Firouzi
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Ayoob Davoodi
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Fariba Bahrami
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
| | - Maziar A Sharbafi
- School of Electrical and Computer Engineering, College of Engineering, University of Tehran, Tehran, Iran
- Lauflabor Laboratory, Technische Universität Darmstadt, Darmstadt, Germany
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Galljamov R, Ahmadi A, Mohseni O, Seyfarth A, Beckerle P, Sharbafi MA. Adjustable Compliance and Force Feedback as Key Elements for Stable and Efficient Hopping. IEEE Robot Autom Lett 2021. [DOI: 10.1109/lra.2021.3095024] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Naseri A, Grimmer M, Seyfarth A, Ahmad Sharbafi M. Neuromechanical force-based control of a powered prosthetic foot. WEARABLE TECHNOLOGIES 2020; 1:e6. [PMID: 39050271 PMCID: PMC11265316 DOI: 10.1017/wtc.2020.6] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 07/31/2020] [Accepted: 08/25/2020] [Indexed: 07/27/2024]
Abstract
This article presents a novel neuromechanical force-based control strategy called FMCA (force modulated compliant ankle), to control a powered prosthetic foot. FMCA modulates the torque, based on sensory feedback, similar to neuromuscular control approaches. Instead of using a muscle reflex-based approach, FMCA directly exploits the vertical ground reaction force as sensory feedback to modulate the ankle joint impedance. For evaluation, we first demonstrated how FMCA can predict human-like ankle torque for different walking speeds. Second, we implemented the FMCA in a neuromuscular transtibial amputee walking simulation model to validate if the approach can be used to achieve stable walking and to compare the performance to a neuromuscular reflex-based controller that is already used in a powered ankle. Compared to the neuromuscular model-based approach, the FMCA is a simple solution with a sufficient push-off that can provide stable walking. Third, to assess the ability of the FMCA to generate human-like ankle biomechanics during walking at the preferred speed, we implemented this strategy in a powered prosthetic foot and performed experiments with a non-amputee subject. The results confirm that, for this subject, FMCA can be used to mimic the non-amputee reference ankle torque and the reference ankle angle. The findings of this study support the applicability and advantages of a new bioinspired control approach for assisting amputees. Future experiments should investigate the applicability to other walking speeds and the applicability to the target population.
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Affiliation(s)
- Amirreza Naseri
- Department of Mechanical Engineering, Tarbiat Modares University, Jalal al-Ahmad, Nasr, Tehran, Iran
| | - Martin Grimmer
- Lauflabor Locomotion Lab, Institute of Sport Science, Centre for Cognitive Science, Technische Universitat Darmstadt, Darmstadt, Germany
| | - André Seyfarth
- Lauflabor Locomotion Lab, Institute of Sport Science, Centre for Cognitive Science, Technische Universitat Darmstadt, Darmstadt, Germany
| | - Maziar Ahmad Sharbafi
- Lauflabor Locomotion Lab, Institute of Sport Science, Centre for Cognitive Science, Technische Universitat Darmstadt, Darmstadt, Germany
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