Vibration suppression for uprising control of two-wheel driven wheelchair

The wheelchair is an important vehicle for handicapped and aged people. But traditional wheelchairs have two problems, low mobility and difficultly of going over steps. These problems are caused by their two front casters. To solve these problems, two-wheel driven wheelchair which has no caster was proposed. By the past research, it can keep stable attitude by the stabilization control, and turn by the turning control. However, because riders get on after the wheelchair is stabilized horizontally, it is easy to lose a balance by disturbance when a rider gets on. In this paper, the uprising control of two-wheel driven wheelchair is proposed. Pitch angle disturbance observer (PADO) and Lyapunov-based controller are utilized to realize uprising and stabilization. In order to suppress the vibrations, the variable gain is proposed. By the proposed control method, riders can get on two-wheel driven wheelchair easily.