Robotic driving assistance system for manual wheelchair user on uneven ground

Abstract

This paper proposes a novel driving assistance system for a manual wheelchair. On an inclined road, there is a high risk of a wheelchair moving in a direction that the user does not intend. Using only servo brakes on each wheel, our proposed system negates the wheel traction that is generated by the road's inclination. Our system measures the road's inclination and estimates the wheel traction generated by gravitational force. Our system then cancels this traction and the user can drive the wheelchair as they would on flat ground. The system is intuitive because the user drives the wheelchair in the usual manner, and our assistance system works passively to complement the user's intentional force. Our system uses only servo brakes that can generate the various required levels of brake traction. Our system does not require actuators, and its mechanism is simple and inexpensive. There is no risk of malfunction of servomotors. We verified the effectiveness of our proposed assistance system by conducting experiments with a prototype.