A simple hybrid/switching strategy for improving linear controllers

This paper presents a method for improving linear controllers once they have been designed using any linear technique. The controller enhancement is achieved by the introduction of a block which varies two parameters according to the error amplitude. It is also presented a stability condition for the designs, based on previous stability results for switching systems. Both the design method and the stability criterion are easy to use for a control engineer, even not being a specialist on switching control. A classical two-mass-spring benchmark control problem is also presented to illustrate the new technique.