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


1 Department of Mechanical Engineering,Sharif University of Technology

2 Department of Electrical & Computer Engineering,Semnan University


Nonlinearity characteristics, such as backlash, in various mechanisms, limit the performance
of feedback systems by causing delays, undesired oscillations and inaccuracy. Backlash in
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 di erential 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
di erent 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