Experimental investigation into passive damping enhancement for space structures

Abstract

This work presents experiments conducted to verify kineticand strain-energy damping enhancement schemes for large/precision space structures. Two types of damping mechanisms were applied to a 5-m-long, 10-bay aluminum cubic box truss with a quasi-free-free suspension. Tunable proof-mass dampers were implemented with space-realizable linear electromechanical drivers. Tunable piezoelectric truss members were designed and constructed for the demonstration of resonant shunted piezoelectric damping concepts. The truss damping was measured and compared with analytical predictions. The proof-mass damper implementation was found to increase the first mode damping ratio from 0.6% of critical to 6.4% of critical with a 2.7% system mass increase. The resonant shunted piezoelectric implementation increased the first mode damping ratio to 6.0%, with a 1.9% increase in system mass.