Title :
Nonlinear Element Compensation by Gain Adjustment and Dither Smoothing
Author :
Lee, Yun-Yao ; Chi, Chien-Yu ; Liu, Kun-Ming
Author_Institution :
Ching Yun Univ., Jung-Li
Abstract :
A novel approach to linearize nonlinearities commonly inherent in actuators is proposed in this paper. This approach solves the inverse of the nonlinearity without requiring its I/O relations as a one-on-one map, which is necessary for the current inverse-model method By introducing the concept of the equivalent gain, the proposed method systematically finds the inverse model of the nonlinearity by solving a zero-finding problem. Discussions on the existence and uniqueness of the solution are given in this paper. A simulation example is presented to demonstrate how the task in finding the inverse of a complicated nonlinearity can be simplified by the proposed method. Experimental evaluations on a position servo system with conspicuous friction reveal that the dither-smoothed nonlinearities are still nonlinear, and compensating action like the proposed method is necessary for control systems using the dithering technology.
Keywords :
actuators; compensation; control nonlinearities; control system synthesis; gain control; inverse problems; linearisation techniques; nonlinear control systems; position control; servomechanisms; smoothing methods; actuator system; compensation method; control nonlinearity; controller design; dither smoothing technology; gain adjustment; inverse problem; linearization technique; nonlinear element compensation; position servo system; zero-finding problem; Control nonlinearities; Control systems; Friction; Hydraulic actuators; Hysteresis; Intelligent control; Inverse problems; Nonlinear control systems; Servomechanisms; Smoothing methods; compensation; dither techniques; friction; inverse problems; linearization; nonlinearities;
Conference_Titel :
Intelligent Control, 2007. ISIC 2007. IEEE 22nd International Symposium on
Conference_Location :
Singapore
Print_ISBN :
978-1-4244-0440-7
Electronic_ISBN :
2158-9860
DOI :
10.1109/ISIC.2007.4450934