Anti Slip Balancing Control for Wheeled Inverted Pendulum Vehicles

This brief proposes an antislip balancing controller for wheel inverted pendulum (WIP) vehicles to deal with various traction environments. The controller is designed based on a general plant model which not only characterizes the dynamics of the pendulum body and the wheels but also the slip effect. As the general model can be decomposed into a convex combination of four linear subsystems with time-varying coefficients, the proposed controller also consists of a convex combination of four linear, full-state feedback controllers. It is proven that if the full-state feedback controllers satisfy a set of linear matrix inequalities, the WIP vehicle can maintain its stability regardless of the change of traction environments during operation. The convex coefficients in the control law are related to the traction force ratios which are identified via a two-step process. The validity of the antislip balancing controller is verified by both numerical simulations and experiments on a prototype WIP vehicle.