基于最小二乘法的工作台油膜厚度控制方法

Oil Film Thickness Control Method Based on Least Square Method

为减少大型重载静压工作台油膜厚度对加工精度的影响,提出了一种基于最小二乘法的工作台油膜厚度控制方法。首先,通过实测工作台在不同载荷和频率下的油膜厚度值,基于最小二乘法曲线拟合的原理,建立油膜厚度、电机频率、载荷之间的数学模型。当目标油膜厚度设定后,依据所建立的数学模型反求出对应的电机目标频率,从而获得满足工作台精度要求的实际油膜厚度。实验结果表明,该方法在实际应用中简单方便,适用于不同工况,且实验误差符合要求。

In order to reduce the influence of oil film thickness of heavy- duty hydrostatic worktable on the machining precision, a method based on the least square method is proposed to control the oil film thickness. Firstly, based on the principle of the least square curve fitting, the mathematical model among oil film thickness, motor frequency and load is established by measuring the thickness of oil film under different loads and frequencies. When the target oil film thickness is set, according to the established mathematical model, the corresponding target frequency of the motor is obtained, so as to obtain the actual oil film thickness which meets the accuracy requirements of the worktable. Experimental results show that the method is simple and convenient in practical applications, and it is suitable for different conditions with permissible errors.