Stability analysis and vibration control of flexible structures using delayed feedback signals

The paper presents a simple position control approach aimed to improve the performance of lightly damped dynamic flexible structures. This approach uses a delayed position feedback signal to actively control the vibrations of flexible structures. The paper shows that an appropriate choice of the delay time and of the gain of the delayed signal significantly improves the time response of the system. A complete analysis of the stability of a single link flexible manipulator under time delay control is presented and critical values of time delay for a given controller gain has been determined. The paper also presents a short comparison between the Delayed Feedback Signal control and the Linear Quadratic Regulator.