光学仪器隔微振系统的负刚度特性分析与验证

Negative stiffness characteristic analysis and verification of optical instruments damping system

为了使大负载光学仪器隔微振系统达到更低的固有频率和更小的传递率,提出了正负刚度并联隔微振方法,利用负刚度发生器产生的载荷增量与变形增量方向相反的特性,并联具有大载荷特性的正刚度元件组成稳定的支承系统,使系统能够在不降低承载的情况下有效降低系统刚度。建立了使用绝对位移反馈方法的大型气浮隔微振装置运动模型,分析了本文方法对运动幅值响应的影响。实验结果表明,被隔振体垂向速度均方根值由5.7μm/s降至2.1μm/s,谐振区传递率能有10dB的降低,验证了本文方法能够有效解决被动控制对低频区控制效果不佳的问题。

In order to make the large load vibration isolation system reach a lower natural frequency and lower transmission rate,the vibration isolator using parallel positive stiffness and negative stiffness is designed for the large load vibration isolation system. The method that negative stiffness generator＇s load increment has the opposite direction to the deformation increment is used. The negative stiffness device characteristics are different from positive stiffness device. The stabilization support system is composed of negative stiffness generator and parallel connected large load positive stiffness generator. The system is more stable than the normal system. It can effectively reduce the system stiffness. And the system can effectively maintain a large load A large-scale air spring vibration isolation platform dynamics model which uses the method of absolute displacement feedback is built. And the impact on motion amplitude response with the large-scale air spring vibration isolation platform is analyzed The experimental results show that the root mean square of vertical velocities is decreased from 5.7 /μm/s to 2.1μm/s and the transmissibility in resonance region is decreased by 10 dB. It can effectively solve the problem of passive control not very effective in the low frequency region.