Stability Analysis of Closed-loop Input Shaping Control

Input shaping is a vibration control technique that operates by filtering reference commands so that the modified (or shaped) command does not excite the system’s natural frequencies. Usually, input shaping is limited to a filtering operation outside of any feedback loops. However, this implementation prevents input shaping from effecting some vital control applications including disturbance rejection, initial condition response, etc. Therefore, some research has suggested using input shapers within feedback loops. This paper will present some initial investigations toward the fundamental understanding of how input shapers utilized within feedback loops affect closed loop stability. Copyright c ©2005 IFAC