Design of a low-cost, reconfigurable, standing wheelchair with easy and stable sit-stand-sit transition capability.

PURPOSE: Assistive devices like Standing Wheelchairs (SWC) have remained out of reach of the economically underprivileged even before the pandemic-induced financial downturn, and more so now. This paper describes the mechanical design of a manual user-actuated SWC that is cost-effective (equivalent of USD 210 in India, ex-factory) and has special features that minimise user effort and accommodates varying body weights (50-110 kg) and dimensions (1.52-1.83 m height). METHODS: The design includes a six-bar mechanism and spring balancing to optimise user effort during operation. The optimised gas spring incorporates adjustability to minimise each user's force for sit-stand-sit transitions. The handle shape is ergonomically designed using kinematic analysis to provide convenient gripping positions for actuation. The design has been customised based on parametric studies to suit varying body weights. RESULTS: Overall, the SWC design provides standing functionality with ease of operation, safety locks, customisability, affordability, outdoor mobility and is aesthetically pleasing. CONCLUSIONS: Customisability and the low cost of the device would enhance the accessibility of the SWC to a larger group of eligible users.Implications for rehabilitationManual user-operated standing wheelchair design using a six-bar mechanismSpring balancing used to reduce user effort to self-lift to the standing positionKinematic analysis used to determine convenient handle location for user easeCustomisability for wide range of users to ensure correct posture, optimal effortDesign refined through multiple iterations using inputs from users and cliniciansDesign commercialised at an affordable cost, making it accessible to a larger population.

Design journey of an affordable manual standing wheelchair.

PURPOSE: Only 1 in 10 people with disabilities can access assistive devices, underlining the critical need for low-cost assistive products. This paper describes the design evolution of a manual user-operated standing wheelchair (SWC), translating from prototype to product. METHODS: The SWC design has been refined over 5 years through multiple iterations based on comments from user trials. The SWC product, Arise, provides standing functionality, facile outdoor mobility, affordability, customisability, and is aesthetically pleasing. A one-time fitting and training ensure optimal effort for operation, correct posture, and comfortable user experience. The SWC accommodates users of different sizes and body weights (up to 110 kg) and minimises user effort with the use of a gas spring. Incorporating discrete adjustments enables customisation while retaining the advantages of mass manufacturing, which is necessary for ensuring affordability. RESULTS: The SWC has been field-tested and well received by over 100 wheelchair users, and Arise was launched recently by the industry partner. CONCLUSIONS: It should be noted that RESNA cautions on the use of any standing device without medical consultation. Nevertheless, with appropriate dissemination and awareness, it is anticipated that the affordable SWC product, Arise, will immensely benefit the eligible users and make a difference in their quality of life.Implications for RehabilitationProvides standing functionality, outdoor mobility, affordability and customisabilityAccommodates users of different sizes and body weights in a mass-manufacturable designErgonomic design reduces net user effort during sit-to-stand, stand-to-sit activityDesign iterated and refined based on feedback from over 100 user trials.

User experience study of an affordable manual standing wheelchair.

PURPOSE: The manual user-operated Arise Standing Wheelchair (SWC) is the end-result of multiple design iterations based on comments from user trials. The Arise SWC provides standing functionality, outdoor mobility, affordability, and customizability. This paper describes a user experience study of the Arise SWC's pre-commercial version. METHODS: Thirty participants (N = 30, 25 Male, 5 Female) were recruited for the study. All the participants were people with spinal cord injury. The study was conducted over a period of six weeks (five participants per week) within the hospital premises under the supervision of clinical personnel. A 30 min interactive training session involved thirteen activities. During the trial period, the participants were trained to perform twenty-two activities to familiarize themselves with the SWC. The participants were also trained to perform four functional usage activities with the SWC. At the end of the study, participant responses to ten outcome measures were captured using a smiley-based Likert-scale questionnaire. RESULTS: A majority of the participants (93.3%) felt happy when they stood in the SWC. The majority participants (83.3%) preferred the Arise SWC over their current wheelchair. Also, 80% participants anticipated that they could get more work done at home using the standing function of the wheelchair. CONCLUSIONS: A one-time fitting and training ensured optimal effort for the SWC operation, correct posture, and comfortable user experience. With proper dissemination and awareness, it is believed that the Arise SWC will benefit eligible users and improve their quality of life.IMPLICATIONS FOR REHABILITATIONThe Arise wheelchair provides standing functionality, outdoor mobility, affordability, and customizability.Study confirms that incorporating standing functionality can improve the quality of life for wheelchair users.The majority of users were happy, felt safe and expected to do more with the standing functionality.Study results support further testing in real world conditions beyond the hospital setting.

GRID: a model for the development of assistive devices in developing countries.

PURPOSE: An" Appropriate Assistive Device" is accessible, affordable and standardised in terms of quality and safety, and most importantly, has the functionality to satisfy the user needs. The cost of research and development (R&D) of such assistive products for a market that has limited purchasing power is a significant hurdle and traditional models of R&D may not work effectively in this case. This paper presents an experience-based viable model for the R&D of assistive devices for users in developing countries. METHOD: The model presented here has been evolved from the functioning of the TTK Centre for Rehabilitation Research and Device Development (R2D2) in IIT Madras, Chennai, India. The model is based on the four pillars of Grants-Research-Industry-Dissemination, hence the name GRID model. We have been effectively using this model involving academia, funding agencies, industry partners and users to develop appropriate assistive devices. Three case studies of assistive device development based on the GRID model are presented in this paper to elucidate practical implementation of the model. RESULTS: Using the GRID model, we have successfully accomplished the development of appropriate assistive devices and two of these devices will be launched in the coming months. CONCLUSIONS: The proposed GRID model is a viable model for the development of appropriate assistive devices in developing countries, and could likely be replicated in other parts of the world as well.IMPLICATIONS FOR REHABILITATIONThe GRID model is practically viable and provides a systematic approach for the development of high-quality, functional and affordable assistive devices.Implementation of the GRID model to develop assistive devices could attract more funding and committed stakeholders to this space, with the potential to change the assistive device landscape in developing countries by making available more functional and affordable devices.In effect, the model will benefit users of assistive devices by giving them a greater choice of available devices and empowering them to lead a quality life.