Driving trajectory generation of electric powered wheelchair using spline curve

This paper describes a novel smooth and stable driving trajectory generation scheme for electric powered wheelchair based on the third order spline curve. Electric powered wheelchair moved by the right and left electric motors based on the human´s joystick input is expected to be widely used as a mobility support system for elderly people and disabled people. As one of the high performance control systems for the electric powered wheelchair, this paper proposes a real-time driving trajectory generation scheme to improve the ride quality and safety. The proposed system generates various driving trajectories with the spline curves based on the circle equations and the future passing positions are estimated using the turning radius circle equations. The human´s intent from the joystick input can be well reflected in the driving trajectory such as the turning radius. The third order spline curve trajectory can be generated from four passing positions including one past passing position, one present position and two estimated future positions. Some simulation and experiment results show the effectiveness of the proposed control system.