Differential Equations and Control Processes
(Differencialnie Uravnenia i Protsesy Upravlenia)

Output Based Iterative Learning Control of an Uncertain System with Input Backlash

Author(s):

Julia Pavlovna Emelianova

Ph.D. Associate Professor of the Department of Applied Mathematics of the Arzamas Polytechnic Institute of R.E. Alekseev Nizhny Novgorod State Technical University

emelianovajulia@gmail.com

Abstract:

This paper considers iterative learning control (ILC) design problem for a discrete system operating in a repetitive mode with the backlash-type nonlinearity, inherent in robot actuators, using the measurable output and with two type of update laws. The system parameters are incompletely known and are described by the affine uncertainty model. The problem statement is motivated by the development trends of high-precision smart and additive manufacturing as well as medical rehabilitation robots. A new ILC design method with direct specification of the reference trajectory is obtained. Using a gantry robot as an example, the influence of the backlash dead zone on the accuracy of the reference trajectory tracking is investigated and a comparative analysis with two type of update laws is given.

Keywords

• input backlash
• iterative learning control
• parameter uncertainties
• vector Lyapunov function

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