FAULT TOLERANT CONTROL

Abstract

In this paper an algorithms is developed for fault diagnosis and fault tolerant control strategy for nonlinear systems subjected to an unknown time-varying fault in the presence of modeling error. Faults in an industrial process could be timely detected and diagnosed in many cases. It is possible to subsequently reconfigure the control system so that it can safely continue its operation (possibly with degraded performance) until the time comes when it can be switched off for maintenance. In order to minimize the chances for drastic events such as a complete failure, safety-critical systems must possess the properties of increased reliability and safety. Faults in robotic systems are inevitable. They have diverse characteristics, magnitudes and origins, from the familiar viscous friction to Coulomb/Sticktion friction, and from structural vibrations. This paper presents an on-line environmental fault detection and an accommodation scheme. The performance of the proposed scheme is applied to a SCARA robot to show the effectiveness of the proposed approach.