ROBUST ADAPTIVE FRICTION COMPENSATION FOR DC MOTORS WITH PARAMETRIC UNCERTAINTIES

A robust adaptive compensation scheme is presented in this paper to compensate the dynamic friction as well as the parametric uncertainties that exist in the DC motor system. A simplified second-order linear model is used for the DC motor system while the LuGre dynamic friction model with non-uniform friction force variations characterizes the friction force in the motor system. The compensation scheme consists of a PID component and an adaptive component for estimating the unknown system parameters. The system stability and the asymptotic position tracking performance are validated by using Lyapunov function and computer simulations verify the effectiveness of the proposed schem for high-precision motion trajectory tracking.