Damping and Structural Control of the JPL Phase 0 Testbed Structure

This paper describes recent advances in structural quieting technology as applied to active truss structures intended for high precision space based optics applica tions. The active structure incorporates piezoelectric active members which exert control forces internal to the structure and thereby improve the structure's dimensional stability. The control architecture involves two layers of feedback control. The first utilizes col located measurements of force and velocity at the active member to achieve active damp ing, the second utilizes noncollocated measurements of acceleration at the location of a simulated optical component to achieve structural stabilization. The local control loops are based on the concept of impedance matching, the global control loops are designed using robust control methods. These two levels of control are intended to operate simulta neously; however, in this paper each approach is applied individually. The combined im plementation is left for future work.