Wheeled inverted pendulum type robotic wheelchair with integrated control of seat slider and rotary link between wheels for climbing stairs

The authors describe a mechanical design and control strategy for an inverted pendulum type robotic wheelchair. The structure of the wheelchair consists of a seat slider and two rotary links between the wheels and tires on either side. In addition, the integrated control is based on a linear-quadratic regulator consisting of a gravity-center control stage and a wheel-linkage control stage for climbing stairs. The authors verified the effectiveness of the control system and the mechanical structure on a physical dynamic simulation. The authors present an overview of the kinematic structure and control strategy for climbing stairs.