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Ding S, Reyes FA, Bhattacharya S, Seyram O, Yu H. A Novel Passive Back-Support Exoskeleton With a Spring-Cable-Differential for Lifting Assistance. IEEE Trans Neural Syst Rehabil Eng 2023; 31:3781-3789. [PMID: 37725739 DOI: 10.1109/tnsre.2023.3317059] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/21/2023]
Abstract
Lower back injuries are the most common work-related musculoskeletal disorders. As a wearable device, a back-support exoskeleton (BSE) can reduce the risk of lower back injuries and passive BSEs can achieve a low device weight. However, with current passive BSEs, there is a problem that the user must push against the device when lifting the leg to walk, which is perceived as particularly uncomfortable due to the resistance. To solve this problem, we propose a novel passive BSE that can automatically distinguish between lifting and walking. A unique spring-cable-differential acts as a torque generator to drive both hip joints, providing adequate assistive torque during lifting and low resistance during walking. The optimization of parameters can accommodate the asymmetry of human gait. In addition, the assistive torque on both sides of the user is always the same to ensure the balance of forces. By using a cable to transmit the spring force, we placed the torque generator on the person's back to reduce the weight on the legs. To test the effectiveness of the device, we performed a series of simulated lifting tasks and walking trials. When lifting a load of 10 kg in a squatting and stooping position, the device was able to reduce the activation of the erector spinae muscles by up to 41%. No significant change in the activation of the leg and back muscles was detected during walking.
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Higgins TM, Bresingham KJ, Schmiedeler JP, Wensing PM. Data-efficient human walking speed intent identification. WEARABLE TECHNOLOGIES 2023; 4:e19. [PMID: 38487770 PMCID: PMC10936302 DOI: 10.1017/wtc.2023.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/23/2023] [Revised: 04/24/2023] [Accepted: 05/06/2023] [Indexed: 03/17/2024]
Abstract
The ability to accurately identify human gait intent is a challenge relevant to the success of many applications in robotics, including, but not limited to, assistive devices. Most existing intent identification approaches, however, are either sensor-specific or use a pattern-recognition approach that requires large amounts of training data. This paper introduces a real-time walking speed intent identification algorithm based on the Mahalanobis distance that requires minimal training data. This data efficiency is enabled by making the simplifying assumption that each time step of walking data is independent of all other time steps. The accuracy of the algorithm was analyzed through human-subject experiments that were conducted using controlled walking speed changes on a treadmill. Experimental results confirm that the model used for intent identification converges quickly (within 5 min of training data). On average, the algorithm successfully detected the change in desired walking speed within one gait cycle and had a maximum of 87% accuracy at responding with the correct intent category of speed up, slow down, or no change. The findings also show that the accuracy of the algorithm improves with the magnitude of the speed change, while speed increases were more easily detected than speed decreases.
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Affiliation(s)
- Taylor M. Higgins
- Department of Mechanical Engineering, Florida A&M - Florida State University, Tallahassee, FL, USA
| | - Kaitlyn J. Bresingham
- Department of Mechanical Engineering, Florida A&M - Florida State University, Tallahassee, FL, USA
| | - James P. Schmiedeler
- Department of Mechanical Engineering, Florida A&M - Florida State University, Tallahassee, FL, USA
| | - Patrick M. Wensing
- Department of Mechanical Engineering, Florida A&M - Florida State University, Tallahassee, FL, USA
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Baldassarre A, Lulli LG, Cavallo F, Fiorini L, Mariniello A, Mucci N, Arcangeli G. Industrial exoskeletons from bench to field: Human-machine interface and user experience in occupational settings and tasks. Front Public Health 2022; 10:1039680. [PMID: 36478728 PMCID: PMC9720272 DOI: 10.3389/fpubh.2022.1039680] [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: 09/08/2022] [Accepted: 10/26/2022] [Indexed: 11/22/2022] Open
Abstract
Objective Work-related musculoskeletal disorders (WRMSDs) are considered nowadays the most serious issue in the Occupational Health and Safety field and industrial exoskeletons appear to be a new approach to addressing this medical burden. A systematic review has been carried out to analyze the real-life data of the application of exoskeletons in work settings considering the subjective responses of workers. Methods The review was registered on PROSPERO. The literature search and its report have been performed following the PRISMA guidelines. A comprehensive literature search was performed in PubMed, EMBASE, Web of Science, and Scopus. Results Twenty-four original studies were included in the literature review; 42% of the papers retrieved included automobilist industry workers, 17% of the studies evaluated the use of exoskeletons in logistic facilities, and 17% of articles involved healthcare. The remaining six papers recruited farmers, plasterers, wasting collectors, construction workers, and other workmen. All the papers selected tested the use of passive exoskeletons, supporting upper arms or back. Usability, perceived comfort, perceived exertion and fatigue, acceptability and intention to use, occupational safety and health, and job performance and productivity were the main topic analyzed. Conclusion Exoskeletons are not a fix-all technology, neither for workers nor for job tasks; they tend to show more of their potential in static activities, while in dynamic tasks, they can obstacle regular job performance. Comfort and easiness of use are the key factors influencing the user's experience. More research is needed to determine the most effective and safe ways to implement exoskeleton use in occupational settings. Systematic review registration https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=275728, identifier CRD42021275728.
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Affiliation(s)
- Antonio Baldassarre
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Lucrezia Ginevra Lulli
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Filippo Cavallo
- Department of Industrial Engineering, University of Florence, Florence, Italy
| | - Laura Fiorini
- Department of Industrial Engineering, University of Florence, Florence, Italy
| | | | - Nicola Mucci
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
| | - Giulio Arcangeli
- Department of Experimental and Clinical Medicine, University of Florence, Florence, Italy
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Ishii C, Hirasawa K. The effect of a movable headrest in shoulder assist device for overhead work. WEARABLE TECHNOLOGIES 2022; 3:e25. [PMID: 38486911 PMCID: PMC10936258 DOI: 10.1017/wtc.2022.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 08/16/2022] [Accepted: 09/05/2022] [Indexed: 03/17/2024]
Abstract
Recently, many kinds of shoulder-support exoskeletons have been developed and some of them are commercially available. However, to the best of our knowledge, shoulder-support exoskeletons that have neck-support mechanism have not been found. During the overhead work, physical strain is added to not only upper limb and shoulder but also neck of workers since the workers work keeping their face raised. Therefore, in this study, to reduce the physical strain on the neck during the overhead work, a movable headrest that can be attached to the shoulder assist device was developed, which has reclining and slide functions of a head. The main purpose of this article was to evaluate usefulness of the proposed movable headrest. To this end, measurements of electromyogram were carried out under simulating an overhead work activity, and the reduction effect for physical strain of the neck was compared among three types of headrests: (a) slide-type headrest which can slide the head backward and forward, (b) reclining-type headrest which can recline the head, and (c) reclining and slide-type headrest which can recline and slide the head. In addition, usefulness of the shoulder assist device with the proposed headrest was evaluated for a realistic overhead work activity through measurements of muscular stiffness of neck and shoulder. The experimental results showed that the existence of the headrest in the shoulder assist device is effective to reduce the physical strain to the workers, and that (c) reclining and slide-type headrest is the most effective among these three types of headrests.
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Affiliation(s)
- Chiharu Ishii
- Department of Mechanical Engineering, Hosei University, Tokyo, Japan
| | - Kanta Hirasawa
- Department of Mechanical Engineering, Hosei University, Tokyo, Japan
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Yang C, Yu L, Xu L, Yan Z, Hu D, Zhang S, Yang W. Current developments of robotic hip exoskeleton toward sensing, decision, and actuation: A review. WEARABLE TECHNOLOGIES 2022; 3:e15. [PMID: 38486916 PMCID: PMC10936331 DOI: 10.1017/wtc.2022.11] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/06/2022] [Revised: 05/22/2022] [Accepted: 06/09/2022] [Indexed: 03/17/2024]
Abstract
The aging population is now a global challenge, and impaired walking ability is a common feature in the elderly. In addition, some occupations such as military and relief workers require extra physical help to perform tasks efficiently. Robotic hip exoskeletons can support ambulatory functions in the elderly and augment human performance in healthy people during normal walking and loaded walking by providing assistive torque. In this review, the current development of robotic hip exoskeletons is presented. In addition, the framework of actuation joints and the high-level control strategy (including the sensors and data collection, the way to recognize gait phase, the algorithms to generate the assist torque) are described. The exoskeleton prototypes proposed by researchers in recent years are organized to benefit the related fields realizing the limitations of the available robotic hip exoskeletons, therefore, this work tends to be an influential factor with a better understanding of the development and state-of-the-art technology.
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Affiliation(s)
- Canjun Yang
- Ningbo Research Institute, Zhejiang University, Ningbo, China
- School of Mechanical Engineering, Zhejiang University, Hangzhou, China
- School of Mechanical and Energy Engineering, NingboTech University, Ningbo, China
| | - Linfan Yu
- Ningbo Research Institute, Zhejiang University, Ningbo, China
- School of Mechanical Engineering, Zhejiang University, Hangzhou, China
| | - Linghui Xu
- Ningbo Research Institute, Zhejiang University, Ningbo, China
- School of Mechanical Engineering, Zhejiang University, Hangzhou, China
| | - Zehao Yan
- Ningbo Research Institute, Zhejiang University, Ningbo, China
- School of Mechanical Engineering, Zhejiang University, Hangzhou, China
| | - Dongming Hu
- School of Mechanical and Energy Engineering, NingboTech University, Ningbo, China
| | - Sheng Zhang
- Ningbo Research Institute, Zhejiang University, Ningbo, China
- School of Mechanical Engineering, Zhejiang University, Hangzhou, China
| | - Wei Yang
- Ningbo Research Institute, Zhejiang University, Ningbo, China
- School of Mechanical Engineering, Zhejiang University, Hangzhou, China
- School of Mechanical and Energy Engineering, NingboTech University, Ningbo, China
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Lazzaroni M, Fanti V, Sposito M, Chini G, Draicchio F, Natali CD, G. Caldwell D, Ortiz J. Improving the Efficacy of an Active Back-Support Exoskeleton for Manual Material Handling Using the Accelerometer Signal. IEEE Robot Autom Lett 2022. [DOI: 10.1109/lra.2022.3183757] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Maria Lazzaroni
- Department of Advanced Robotics, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - Vasco Fanti
- Department of Advanced Robotics, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - Matteo Sposito
- Department of Advanced Robotics, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - Giorgia Chini
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Rome, Italy
| | - Francesco Draicchio
- Department of Occupational and Environmental Medicine, Epidemiology and Hygiene, INAIL, Rome, Italy
| | - Christian Di Natali
- Department of Advanced Robotics, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - Darwin G. Caldwell
- Department of Advanced Robotics, Istituto Italiano di Tecnologia (IIT), Genova, Italy
| | - Jesus Ortiz
- Department of Advanced Robotics, Istituto Italiano di Tecnologia (IIT), Genova, Italy
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Tabasi A, Lazzaroni M, Brouwer NP, Kingma I, van Dijk W, de Looze MP, Toxiri S, Ortiz J, van Dieën JH. Optimizing Calibration Procedure to Train a Regression-Based Prediction Model of Actively Generated Lumbar Muscle Moments for Exoskeleton Control. SENSORS (BASEL, SWITZERLAND) 2021; 22:87. [PMID: 35009627 PMCID: PMC8747305 DOI: 10.3390/s22010087] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/15/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
The risk of low-back pain in manual material handling could potentially be reduced by back-support exoskeletons. Preferably, the level of exoskeleton support relates to the required muscular effort, and therefore should be proportional to the moment generated by trunk muscle activities. To this end, a regression-based prediction model of this moment could be implemented in exoskeleton control. Such a model must be calibrated to each user according to subject-specific musculoskeletal properties and lifting technique variability through several calibration tasks. Given that an extensive calibration limits the practical feasibility of implementing this approach in the workspace, we aimed to optimize the calibration for obtaining appropriate predictive accuracy during work-related tasks, i.e., symmetric lifting from the ground, box stacking, lifting from a shelf, and pulling/pushing. The root-mean-square error (RMSE) of prediction for the extensive calibration was 21.9 nm (9% of peak moment) and increased up to 35.0 nm for limited calibrations. The results suggest that a set of three optimally selected calibration trials suffice to approach the extensive calibration accuracy. An optimal calibration set should cover each extreme of the relevant lifting characteristics, i.e., mass lifted, lifting technique, and lifting velocity. The RMSEs for the optimal calibration sets were below 24.8 nm (10% of peak moment), and not substantially different than that of the extensive calibration.
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Affiliation(s)
- Ali Tabasi
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam Movement Sciences, 1081BT Amsterdam, The Netherlands; (N.P.B.); (I.K.); (J.H.v.D.)
| | - Maria Lazzaroni
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, 16163 Genova, Italy; (M.L.); (S.T.); (J.O.)
| | - Niels P. Brouwer
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam Movement Sciences, 1081BT Amsterdam, The Netherlands; (N.P.B.); (I.K.); (J.H.v.D.)
| | - Idsart Kingma
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam Movement Sciences, 1081BT Amsterdam, The Netherlands; (N.P.B.); (I.K.); (J.H.v.D.)
| | | | | | - Stefano Toxiri
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, 16163 Genova, Italy; (M.L.); (S.T.); (J.O.)
| | - Jesús Ortiz
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, 16163 Genova, Italy; (M.L.); (S.T.); (J.O.)
| | - Jaap H. van Dieën
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit, Amsterdam Movement Sciences, 1081BT Amsterdam, The Netherlands; (N.P.B.); (I.K.); (J.H.v.D.)
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Babič J, Laffranchi M, Tessari F, Verstraten T, Novak D, Šarabon N, Ugurlu B, Peternel L, Torricelli D, Veneman JF. Challenges and solutions for application and wider adoption of wearable robots. WEARABLE TECHNOLOGIES 2021; 2:e14. [PMID: 38486636 PMCID: PMC10936284 DOI: 10.1017/wtc.2021.13] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Revised: 08/25/2021] [Accepted: 09/18/2021] [Indexed: 03/17/2024]
Abstract
The science and technology of wearable robots are steadily advancing, and the use of such robots in our everyday life appears to be within reach. Nevertheless, widespread adoption of wearable robots should not be taken for granted, especially since many recent attempts to bring them to real-life applications resulted in mixed outcomes. The aim of this article is to address the current challenges that are limiting the application and wider adoption of wearable robots that are typically worn over the human body. We categorized the challenges into mechanical layout, actuation, sensing, body interface, control, human-robot interfacing and coadaptation, and benchmarking. For each category, we discuss specific challenges and the rationale for why solving them is important, followed by an overview of relevant recent works. We conclude with an opinion that summarizes possible solutions that could contribute to the wider adoption of wearable robots.
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Affiliation(s)
- Jan Babič
- Laboratory for Neuromechanics and Biorobotics, Department of Automation, Biocybernetics and Robotics, Jožef Stefan Institute, Ljubljana, Slovenia
| | - Matteo Laffranchi
- Rehab Technologies Lab, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Federico Tessari
- Rehab Technologies Lab, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Tom Verstraten
- Robotics & Multibody Mechanics Research Group, Vrije Universiteit Brussel and Flanders Make, Brussels, Belgium
| | - Domen Novak
- University of Wyoming, Laramie, Wyoming, USA
| | - Nejc Šarabon
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
| | - Barkan Ugurlu
- Biomechatronics Laboratory, Faculty of Engineering, Ozyegin University, Istanbul, Turkey
| | - Luka Peternel
- Delft Haptics Lab, Department of Cognitive Robotics, Delft University of Technology, Delft, The Netherlands
| | - Diego Torricelli
- Cajal Institute, Spanish National Research Council, Madrid, Spain
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Marinou G, Millard M, Šarabon N, Mombaur K. Comparing the risk of low-back injury using model-based optimization: Improved technique versus exoskeleton assistance. WEARABLE TECHNOLOGIES 2021; 2:e13. [PMID: 38486634 PMCID: PMC10936265 DOI: 10.1017/wtc.2021.12] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 08/24/2021] [Accepted: 08/24/2021] [Indexed: 03/17/2024]
Abstract
Although wearable robotic systems are designed to reduce the risk of low-back injury, it is unclear how effective assistance is, compared to improvements in lifting technique. We use a two-factor block study design to simulate how effective exoskeleton assistance and technical improvements are at reducing the risk of low-back injury when compared to a typical adult lifting a box. The effects of assistance are examined by simulating two different models: a model of just the human participant, and a model of the human participant wearing the SPEXOR exoskeleton. The effects of lifting technique are investigated by formulating two different types of optimal control problems: a least-squares problem which tracks the human participant's lifting technique, and a minimization problem where the model is free to use a different movement. Different lifting techniques are considered using three different cost functions related to risk factors for low-back injury: cumulative low-back load (CLBL), peak low-back load (PLBL), and a combination of both CLBL and PLBL (HYB). The results of our simulations indicate that an exoskeleton alone can make modest reductions in both CLBL and PLBL. In contrast, technical improvements alone are effective at reducing CLBL, but not PLBL. The largest reductions in both CLBL and PLBL occur when both an exoskeleton and technical improvements are used. While all three of the lifting technique cost functions reduce both CLBL and PLBL, the HYB cost function offers the most balanced reduction in both CLBL and PLBL.
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Affiliation(s)
- Giorgos Marinou
- Optimization, Robotics and Biomechanics (ORB), Institute of Computer Engineering (ZITI), Heidelberg University, Heidelberg, Germany
| | - Matthew Millard
- Optimization, Robotics and Biomechanics (ORB), Institute of Computer Engineering (ZITI), Heidelberg University, Heidelberg, Germany
| | - Nejc Šarabon
- Faculty of Health Sciences, University of Primorska, Izola, Slovenia
| | - Katja Mombaur
- Canada Excellence Research Chair in Human-Centred Robotics and Machine Intelligence, Systems Design Engineering & Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario, Canada
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Poliero T, Sposito M, Toxiri S, Di Natali C, Iurato M, Sanguineti V, Caldwell DG, Ortiz J. Versatile and non-versatile occupational back-support exoskeletons: A comparison in laboratory and field studies. WEARABLE TECHNOLOGIES 2021; 2:e12. [PMID: 38486626 PMCID: PMC10936340 DOI: 10.1017/wtc.2021.9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Revised: 07/01/2021] [Accepted: 07/06/2021] [Indexed: 03/17/2024]
Abstract
Assistive strategies for occupational back-support exoskeletons have focused, mostly, on lifting tasks. However, in occupational scenarios, it is important to account not only for lifting but also for other activities. This can be done exploiting human activity recognition algorithms that can identify which task the user is performing and trigger the appropriate assistive strategy. We refer to this ability as exoskeleton versatility. To evaluate versatility, we propose to focus both on the ability of the device to reduce muscle activation (efficacy) and on its interaction with the user (dynamic fit). To this end, we performed an experimental study involving healthy subjects replicating the working activities of a manufacturing plant. To compare versatile and non-versatile exoskeletons, our device, XoTrunk, was controlled with two different strategies. Correspondingly, we collected muscle activity, kinematic variables and users' subjective feedbacks. Also, we evaluated the task recognition performance of the device. The results show that XoTrunk is capable of reducing muscle activation by up to in lifting and in carrying. However, the non-versatile control strategy hindered the users' natural gait (e.g., reduction of hip flexion), which could potentially lower the exoskeleton acceptance. Detecting carrying activities and adapting the control strategy, resulted in a more natural gait (e.g., increase of hip flexion). The classifier analyzed in this work, showed promising performance (online accuracy > 91%). Finally, we conducted 9 hours of field testing, involving four users. Initial subjective feedbacks on the exoskeleton versatility, are presented at the end of this work.
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Affiliation(s)
- Tommaso Poliero
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Matteo Sposito
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy
- Dipartimento di Elettronica, Informazione e Bioingegneria (DEIB), Politecnico di Milano, Milan, Italy
| | - Stefano Toxiri
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Christian Di Natali
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Matteo Iurato
- Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genoa, Genova, Italy
| | - Vittorio Sanguineti
- Department of Informatics, Bioengineering, Robotics and Systems Engineering, University of Genoa, Genova, Italy
| | - Darwin G. Caldwell
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy
| | - Jesús Ortiz
- Department of Advanced Robotics, Istituto Italiano di Tecnologia, Genova, Italy
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