Mixed feedback and feedforward control design for multi-axis vibration isolation systems

This paper proposes a multi-loop single-input single-output control strategy for multi-axis vibration isolation systems. In this strategy, a combination of acceleration feedback and relative position feedback is used to improve the suppression of disturbances acting directly on the isolated payload. In addition, feedforward control is used to counteract the effect of floor vibrations. By mixing the control loops, amplification of sensor noise is minimized while performance in terms of vibration isolation and leveling is optimized. Experimental validation of the control strategy at an industrial vibration isolation system demonstrates performance improvement within the frequency range of interest in multiple directions, which illustrates the effectiveness and usefulness of the proposed design method.