Design, Construction and Control of a 7 DoF Wheelchair-Mounted Robotic Arm

A wheelchair-mounted robotic arm (WMRA) was designed and built to meet the needs of mobility-impaired persons with limitations of upper extremities, and to exceed the capabilities of current devices of this type. The mechanical design incorporates DC servo drive, with actuator hardware at each individual joint, allowing reconfigurable link lengths. It has seven degrees of freedom and uses a side mount on a power wheelchair. The control system is built and designed for user-driven or autonomous coordinated Cartesian control, and it offers expandability for future research, such as coordinated motion with the wheelchair itself. This paper discusses the current state of the art in WMRAs; describes the design goals and user requirements for this device; explains the component selection and the mechanical/electrical design; describes the controller design of the arm and optimized redundancy resolution for the Cartesian control. Further improvements are also suggested