Experimental implementation of integrator backstepping and passive nonlinear controllers on the RTAC testbed

Abstract

This paper fully describes the RTAC experimental testbed which provides a means for implementing and evaluating nonlinear controllers. The description of the testbed includes all physical parameters of the device that are relevant to the design and implementation of controllers. Next, four nonlinear controllers are considered. The first controller is a static, full-state-feedback, globally asymptotically stabilizing control law developed using partial feedback linearization and integrator backstepping. Next, three nonlinear controllers based upon passivity principles are presented, two of which are encompassed by the classical passivity framework, while the third is based upon the novel concept of virtual resetting absorbers. The passive controllers do not require either translational position or velocity measurements. All of the controllers are implemented on the RTAC testbed and their performance is examined. © 1998 John Wiley & Sons, Ltd.