ON TIME-DELAY IN NONCOLOCATED CONTROL OF FLEXIBLE MECHANICAL SYSTEMS

A new method is presented for noncolocated control of flexible mechanical systems. The destabilizing effect of noncolocation of sensors and actuators is eliminated through introduction of specific time delay block (s) in the control system. The time delay constants in those blocks depend on the system eigenstructure. For a given flexible mechanical system, if there exists a time delay relation, the system response at one point can be exactly predicted from the vibration measurement at other point(s) of the system. In this case all stabilizing controllers from colocated control can be directly used. The time delay theory is verified by experiments on noncolocated control of a translating string.