Position control and vibration suppression of a flexible beam-like structure cantilevered from a rotary actuator within a gravitational field

Abstract

An analytical and experimental investigation into the position and vibration control of beam-like structures within a gravity field using only root actuation was performed. Two methods were used to linearize the system's equations of motion. This, in turn, allowed for the use of powerful Modern Control Theory pole-location techniques to determine proper feedback-control gains. The control law was implemented on an IBM PC capable of analog/digital conversion. A DC servo motor served as the control actuator. Gains were computed for a continuous controller rather than for one having a sampled-data nature.

Both simulation and experimental response were good, and were seen to correspond well with computed system-eigenvalues. If gains were chosen to cause more negative eigenvalues, the system's response speed increased, as it should. If eigenvalues are forced to become too negative, however, the system becomes too fast for the controller, and response deteriorated.