Design
of a Sliding Mode Controller with a Nonlinear Time-Varying Sliding
Surface
Author:
S
Tokat, I Eksin, M Güzelkaya and M T Söylemez
Year:
2003
(3)
Journal:
Transactions
of the Institute of Measurement and Control
Volume:
325(2)
Pages:
145 - 162
Abstract:
In this study, a new sliding
surface design approach for second-order systems is proposed that varies
the sliding surface in a nonlinear and time-varying fashion. The control
law is reformulated by using the new surface that is defined in the new
co-ordinate axis. The nonlinear surface is then moved in a proper
direction by using a time-varying function. Simulations are performed on
a second-order nonlinear model of a two-link planar manipulator system.
The results of the new design methodology are compared with a classical
sliding mode controller and a sliding mode controller possessing a
discretely moving sliding surface. It has been shown that the proposed
method has improved the system performance in terms of a decrease in the
reaching time, robustness to disturbances and smoother phase plane
trajectory. The decrease obtained in the reaching time is quite
valuable, as it improves the robustness of the controlled system to
external disturbances and parameter variations.