A multi-point decentralized control for mitigating vibration of flexible space structures using reaction wheel...

Area of Science:

• Spacecraft engineering
• Control systems
• Structural dynamics

Background:

• Large-amplitude, low-frequency vibrations in flexible space structures compromise spacecraft attitude stability and pointing precision.
• Effective vibration mitigation is crucial for maintaining operational integrity and mission success.

Purpose of the Study:

• To propose and investigate a multi-point decentralized control strategy for mitigating vibrations in flexible space structures using reaction wheel (RW) actuators.
• To demonstrate the effectiveness of this control strategy through theoretical analysis, numerical simulations, and experimental validation.

Main Methods:

• Derivation of motion equations for a solar array with multiple RW actuators in modal coordinates.
• Design of a decentralized control strategy based on natural frequencies and mode shapes to suppress structural response.
• Theoretical proof of closed-loop dynamic system stability and performance.

Main Results:

• The decentralized control strategy significantly reduces vibration attenuation time: 85.25% for sun-pointing maneuvers and 94.16% for rest-to-rest maneuvers.
• A minor 2% increase in total mass due to actuator addition yields substantial vibration reduction.
• Experimental results confirm the effectiveness of the proposed control method.

Conclusions:

• The proposed multi-point decentralized control strategy using RW actuators is a valid and effective approach for vibration mitigation in flexible space structures.
• This method offers significant improvements in vibration attenuation time with minimal mass penalty, demonstrating its potential for spacecraft design.