Authors: Takayuki Yamamoto; Gan Chen; Isao Takami
Addresses: Faculty of Science and Engineering, Nanzan University, Aichi, Japan ' Faculty of Science and Engineering, Nanzan University, Aichi, Japan ' Faculty of Science and Engineering, Nanzan University, Aichi, Japan
Abstract: This paper proposes a method to solve practical problems of positioning control using a ball screw system. The practical problems contain two difficulties. First difficulty is that friction reduces the positioning performance. In this paper, the friction is divided into three components, which are a linear term including viscous friction, the Stribeck effect and a nonlinear term including static friction and Coulomb friction. The linear term friction can be considered in the framework of linear control synthesis. The nonlinear friction and the Stribeck effect are considered as disturbances. These are compensated by adding one integrator inside the controlled loop and loop shaping. The second difficulty is that the change in the mass of the load affects the system response. Moreover, it is shown that the viscous friction coefficient varies by some experiments. The controller is designed to guarantee the robust stability for uncertain parameters, which are the mass of the load and the viscous friction coefficient. The effectiveness of the proposed method is verified by simulations and experiments.
Keywords: ball screw systems; high precision control; friction compensation; Stribeck effect; stick slip motion; H-infinity control; robust stability; polytopic representation; loop shaping; linear matrix inequalities; LMIs; robust control; friction modelling; positioning control; viscous friction; static friction; Coulomb friction; controller design; simulation.
International Journal of Modelling, Identification and Control, 2016 Vol.26 No.3, pp.207 - 217
Received: 12 May 2015
Accepted: 23 Nov 2015
Published online: 08 Nov 2016 *