Pii: S0094-5765(00)00163-6
نویسندگان
چکیده
This paper presents a new approach to vibration reduction of >exible spacecraft during attitude control by using pulse width pulse frequency (PWPF) modulator for thruster Cring and smart materials for active vibration suppression. The experiment was conducted on the Naval Postgraduate School (NPS)’s >exible spacecraft simulator (FSS), which consists of a central rigid body and an L-shape >exible appendage. A pair of on–oE thrusters are used to re-orient the FSS. To actively suppress vibrations introduced to the >exible appendage, embedded piezoelectric ceramic patches are used as both sensors and actuators to detect and counter react to the induced vibration. For active vibration suppression using the piezoelectric ceramic patches, positive position feedback (PPF) control targeting at the Crst two >exible modes of the FSS system is used. Experimental results demonstrate the eEectiveness of the control strategy of PWPF modulation for attitude control and PPF for active vibration suppression. ? 2001 Elsevier Science Ltd. All rights reserved
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