Design of a power-assist wheelchair for persons with hemiplegia

Persons with hemiplegia often require a one arm drive wheelchair. Current designs exhibit substantially degraded performance when compared to a standard manual wheelchair. A power-assist, one arm drive wheelchair was developed that was maneuverable, foldable and easy to operate. A motor powers the wheel on the user´s affected side, encoders on both rear wheels track wheel positions and a rotary heel interface mounted on a footrest controls steering. A control system analyzes wheel and steering positions and responds to the motion of the hand-driven wheel. The prototype met and exceeded predetermined design specifications based on standard industry test procedures. The power-assist components could be attached to a wide range of manual wheelchairs with only minimal modifications.