根据基础振动的特征，从刚体运动学的角度，分别建立了基础随机振动和正弦振动对精密离心机平均向心加速度影响的数学模型，进行了理论分析和数值仿真，提出了减小基础振动影响的方法，即通过时间平均可减小随机振动和正弦振动的影响。平均时间延长有利于减小基础振动引入的误差。当平均时间为离心机旋转周期的整数倍时，可部分消除由离心机旋转引起的与转速同频的正弦振动的影响；由于相位差的影响，与离心机转速同频的正弦振动会引入一个系统误差项，该项误差不能通过平均的方式减小，相应的补偿方法还应进一步研究。%Based on the characteristics of foundation vibration and rigid body kinematics, the mathematical models for analyzing the affect of random vibration and harmonic vibration of foundation on the average centripetal acceleration of precise centrifuges were established respectively. Then, theoretical analysis and numerical simulation of these models were done. The method to reduce the affect of the foundation vibration was put forward. The influence of foundation vibration can be decreased by time averaging, and the extension of the average time can reduce the foundation-vibration induced error. The influence of harmonic vibration caused by centrifuge rotation can be partly eliminated by the time averaging when the average time is an integer multiple of the centrifuge’s rotation period. However, a system error will be introduced to the average centripetal acceleration if the frequency of the harmonic vibration is the same as that of the centrifuge’s rotational speed. In this case the error can not be eliminated or reduced by the time averaging, and the appropriate compensation method should be studied further.
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