User-centered design and development of TWIN-Acta: A novel control suite of the TWIN lower limb exoskeleton for the rehabilitation of persons post-stroke

Abstract

IntroductionDifficulties faced while walking are common symptoms after stroke, significantly reducing the quality of life. Walking recovery is therefore one of the main priorities of rehabilitation. Wearable powered exoskeletons have been developed to provide lower limb assistance and enable training for persons with gait impairments by using typical physiological movement patterns. Exoskeletons were originally designed for individuals without any walking capacities, such as subjects with complete spinal cord injuries. Recent systematic reviews suggested that lower limb exoskeletons could be valid tools to restore independent walking in subjects with residual motor function, such as persons post-stroke. To ensure that devices meet end-user needs, it is important to understand and incorporate their perspectives. However, only a limited number of studies have followed such an approach in the post-stroke population.MethodsThe aim of the study was to identify the end-users needs and to develop a user-centered-based control system for the TWIN lower limb exoskeleton to provide post-stroke rehabilitation. We thus describe the development and validation, by clinical experts, of TWIN-Acta: a novel control suite for TWIN, specifically designed for persons post-stroke. We detailed the conceived control strategy and developmental phases, and reported evaluation sessions performed on healthy clinical experts and people post-stroke to evaluate TWIN-Acta usability, acceptability, and barriers to usage. At each developmental stage, the clinical experts received a one-day training on the TWIN exoskeleton equipped with the TWIN-Acta control suite. Data on usability, acceptability, and limitations to system usage were collected through questionnaires and semi-structured interviews.ResultsThe system received overall good usability and acceptability ratings and resulted in a well-conceived and safe approach. All experts gave excellent ratings regarding the possibility of modulating the assistance provided by the exoskeleton during the movement execution and concluded that the TWIN-Acta would be useful in gait rehabilitation for persons post-stroke. The main limit was the low level of system learnability, attributable to the short-time of usage. This issue can be minimized with prolonged training and must be taken into consideration when planning rehabilitation.DiscussionThis study showed the potential of the novel control suite TWIN-Acta for gait rehabilitation and efficacy studies are the next step in its evaluation process.

The most used questionnaires for evaluating the usability of robots and smart wearables: A scoping review

“…As shown in Figure 3 , the majority of articles focusing on the most used questionnaires for evaluating the usability of robots and smart wearables were published in 2020 ( n = 11), 22 – 29 , 52 – 54 2021 ( n = 9), 1,0– 34 , 55 – 57 and 2022 ( n = 10), 35 – 41 , 58 – 60 respectively (More details in Table 2 ).…”

Co-design for stroke intervention development: Results of a scoping review

“…In terms of recruitment-related limitations and challenges, many researchers reported difficulty recruiting participants with stroke and clinicians (e.g., [ 26 , 45 , 48 , 51 , 55 , 60 , 65 , 104 , 116 , 126 ]). Reasons for recruitment challenges included participant burden associated with high time commitments for activities [ 65 ], limited technological access for participation during the COVID-19 pandemic [ 51 ], and time and resource constraints for conducting the co-design study and accommodating end-users’ differing needs (e.g., [ 26 , 53 , 55 , 56 , 107 , 116 ]). Individuals with stroke declined to participate in studies due to poor health and lack of perceived benefit [ 114 ] or were ineligible to participate in some studies due to certain cognitive, communication or functional impairments (e.g., [ 51 , 74 , 78 , 104 ]).…”

“…Prior to data collection, many researchers developed recruitment and data collection activities, questions and prompts with individuals with stroke (e.g., an advisory committee) or pilot tested these with individuals who had a stroke to ensure these were appropriate (e.g., could enable discussion and agreement and allow individuals with stroke decision-making power [ 65 ]) and accessible (e.g., delivery format to accommodate differing communication needs (e.g. [ 43 , 54 , 65 , 73 ]) for people with stroke (e.g., an advisory board and/or each participant), as well as feasible (e.g., time to completion fell within the allotted time) (e.g., [ 32 , 116 ]). In addition, some researchers hired experts, including an animator, speech-language pathologist, graphic designer, and professional voice recording artist, to create generative materials to develop data collection tools to help meaningfully involve participants and elicit rich dialogue (e.g., [ 43 , 46 , 65 ]).…”

“…Subcategory 1) Recruitment-related limitations, challenges and strategies. In terms of recruitment-related limitations and challenges, many researchers reported difficulty recruiting participants with stroke and clinicians (e.g., [26,45,48,51,55,60,65,104,116,126]). Reasons for recruitment challenges included participant burden associated with high time commitments for activities [65], limited technological access for participation during the COVID-19 pandemic [51], and time and resource constraints for conducting the co-design study and accommodating end-users' differing needs (e.g., [26,53,55,56,107,116]).…”

“…Semprini, 2022 [116] To identify the users' needs and develop a control system for a lower limb stroke rehabilitation exoskeleton Lower limb exoskeleton for stroke rehabilitation (TWIN exoskeleton; modifying it for people with stroke; initially designed for people with spinal cord injury)…”