摘要 |
<p>An active vibration reducing system for controlling the vibration generated by a source of periodic or quasi-periodic vibration is characterised in that a weighted sum of the output of at least two sinusoidal waveform generators each synchronised to the frequency of the source of original vibration to generate harmonics of the frequency of the source, is supplied to at least one actuator (5) which generates additional vibration, sensor means (6) is used to monitor the effect of the additional vibration on the original vibration and the weighting of the sum of the outputs is adjusted so that within a defined region the amplitude of the combined vibration is reduced.</p> |