Wheelchair users often face architectural barriers such as curbs, limiting their accessibility, mobility, and participation in their communities. The mobility enhancement robotic (MEBot) wheelchair was developed to navigate over such architectural barriers. Its application allows wheelchair users to negotiate curbs automatically while the user remains in control. The application was optimized from a manual to a semiautomated process based on wheelchair users' feedback. The optimized application was evaluated by experienced wheelchair users who navigated over curbs of different heights. Participants evaluated MEBot in terms of effectiveness, workload demand, and usability. Ten participants successfully ascended and descended curbs of different heights at an average completion time of 55.7 ± 19.5 and 30.3 ± 9.1 s, respectively. MEBot maintained stability during the process, while participants reported low levels of effort, frustration, and overall cognitive demand to operate MEBot. Furthermore, participants were satisfied with the ease of learning and using the MEBot curb negotiation application to overcome the curbs but suggested less wheel adjustment for comfort and a faster pace to overcome curbs during real-world conditions.

Most wheelchairs have low directional stability due to their wheel-drive system configurations. Hence, when a wheelchair experiences excessive slip, it will create an uncontrollable moment that changes its heading direction, endangering the safety of the wheelchair user. This paper presents an approach to longitudinal slip reduction (or traction control) for an Electric Powered Wheelchair that uses a variable reference model, which is a mass-damper system. The position of a joystick is mapped to force and torque values, which are the input to this model. The output is the desired trajectory, which is fed to a trajectory tracking controller. The key idea is that if slip occurs, the applied torque to the wheels is reduced by decreasing the desired acceleration, which is achieved by changing the parameters of the reference model. In this study, the mass of the reference model is changed. The proposed slip reduction approach is validated via experiments.

The ability to perform activities of daily living and mobility-related activities of daily living are substantial indicators of one's ability to live at home and to participate in one's community. Technologies to assist with mobility and manipulation are among the most important tools that clinicians can provide to people with disabilities to promote independence and community participation. For people with severe disabilities involving both the upper and lower extremities, there are few systems that provide practical and coordinated assistance with mobility and manipulation tasks. The personal mobility and manipulation appliance (PerMMA) was created in response to goals set forth by a team of clinicians and people with disabilities.