Backlash Nonlinearity Modeling and Adaptive Controller Design for an Electromechanical Power Transmission System

Abstract. Nonlinearity characteristics, such as backlash, in various mechanisms, limit the perfor-mance of feedback systems by causing delays, undesired oscillations and inaccuracy. Backlash in uence analysis and modeling is necessary to design a precision controller for this nonlinearity. Backlash between meshing gears in an electromechanical system is modeled by the use of dierential equations and a nonlinear spring-damper. According to this model, the paper shows that oscillations and delays cannot be compensated by a state feedback controller. Therefore, an adaptive algorithm is designed, based on dierent regions of the system angular position error. Since this controller needs an estimation of the backlash value, it is estimated by a learning unit in the adaptive controller. Simulations show that the presented adaptive controller can eliminate backlash oscillations properly, in accordance with previous works