Adaptive nonlinear control of wheelchair with independent active suspension system

The growing number of elder people is a huge problem in Macau, China, especially, the elder people who loss living ability. In medical area, the complicating disease, such as press sore is one of the most dangerous reason to cause disabled people death. Therefore, some relative research projects are still developing. This paper address the problem of driving a smart wheelchair with independent active suspension system to follow a desired path. Based on a practical wheelchair, Krama KM5000.2, the suspension was a nonlinear system. The solution consists of a Lyapunov-based trajectory tracking control law and an active force for correcting vehicle running attitude. When the wheelchair is working, active suspension generates an active force to against vehicle attitude error. In detail, the paper demonstrates how Lyapunov based techniques yield a control structure includes i) active force against vehicle attitude error, i) saturation on position error and iii) nonlinear damping disturbance.