Multi-degree-of-freedom Active Vibration Isolation Method Based on Composite Feedforward and Feedback Control Strategy

With the rapid development of precision manufacturing, optical inspection, and spacecraft payloads, the stability requirements for micro-vibration environments in high-precision equipment are becoming increasingly strict. Therefore, it is crucial to reduce or isolate environmental vibrations, especially low-frequency and micro-amplitude vibrations. To address the challenge of suppressing low-frequency vibrations, a multi-degree-of-freedom active vibration isolation method based on composite feedforward and feedback control strategy is proposed, with comprehensive theoretical analysis of its operational principles. Comparative experimental validation is conducted on a designed low-frequency multi-axis isolation platform. Results demonstrate that implementation of the method achieves over 60% attenuation in root mean square (RMS) values of tri-axial vibration velocity, coupled with minimum 15 dB reduction in resonance peaks across tri-axial transfer functions.