Supervisory Control of Families of Linear Set-Point Controllers

Professor Stephen Morse, Department of Electrical Engineering, Yale University

This talk will describe a simple, "high-level" controller called a "supervisor" which is capable of switching into feedback with a siso process, a sequence of linear positioning or set-point controllers from a family ${\cal F}_C$ of candidate controllers, so as to cause the output of the process to approach and track a constant reference input. The process is assumed to be modeled by a siso linear system whose transfer function is in the union of a number of subclasses, each subclass being small enough so that one of the controllers in ${\cal F}_C$ would solve the positioning problem, were the process's transfer function to be one of the subclass's members. The supervisor decides which controller to put in feedback with the process, not by an exhaustive search - i.e., by experimentally evaluating each and every candidate controller's performance by briefly applying it to the process - but rather by continuously comparing in real time suitably defined normed values of "output estimation errors" generated by the candidate controllers, whether or not they are in feedback with the process. Results will be presented characterizing the supervisor's ability to perform its function in the face of norm-bounded modelling errors and disturbances.