Active Damping Design of Flexible Structures Based on SISO and SIMO Noncollocated Sensor-Actuator Velocity Feedback

An active damping design technique based on single input velocity feedback is presented in this paper. The stability conditions for each individual mode in SISO and SIMO velocity feedback are demonstrated. Since these stability conditions are derived using modal information, it is appropriate to incorporate this technique with the commonly used dynamic analysis techniques, such as experimental modal analysis and finite element analysis, for active damping design. Based on these stability conditions, two active damping design algorithms are proposed: 1) Constrained Least Squares Feedback Gain Computation, and 2) Optimal Feedback Gain Computation With Flexible Damping Factors. The first algorithm is a straightforward method to find the feedback vector for the given damping factors and the modal frequencies. The second algorithm is based on an optimization process which allows freedom in chosing the desired damping factors. The problem of locating the actuator and sensors is also discussed in this paper. The stability theory and active damping design technique are verified by an experimental example.