Modelling and control of a power-assisted mobile vehicle based on torque observer

The modelling and control of a power-assisted mobile vehicle (PAMV) based on a torque observer are presented. In particular, a human, who recognises the environment, plans the trajectory without danger of collision. The mobile vehicle can generate more power than a human. A human-guided powered mobile vehicle is developed. A dynamic model of this vehicle is constructed by Lagrangian´s equation. A torque observer, designed using the Lyapunov stability theorem, is applied to estimate the external human thrust. The observer gain could be well designed by the proposed method. According to the estimated thrust, two driving wheels controlled by two servomotors provide appropriate assisted force for the PAMV. The feasibility of the proposed control frame is proven and the experimental results demonstrate that the proposed system has high precision and efficiency human-guided .