Active Disturbance Rejection Control for Manipulator Flexible Joint with Dynamic Friction and Uncertainties Compensation

The active disturbance rejection control (ADRC) for high-precision trajectory tracking of manipulator flexible joint is researched. The dynamics model with friction and uncertainties external disturbances of system is established. In order to study the effect and compensation of friction, a dynamic LuGre friction model is introduced. A control strategy of the inner and outer loops control using ADRC is designed based on the system. The friction and the external disturbances are estimated accurately using extended state observer (ESO) and compensated during each sampling period. The designed controller satisfies the quick response speed and steady-state accuracy demands. The simulation results indicate that the designed of the double closed-loop control system has high-precision, adaptability and stronger robustness and has very attractively in engineering practice.