基于理论建模和ARX模型的定位平台系统辨识

System identification of a positioning stage based on theoretical modeling and an ARX model

为了解精密定位平台的系统特性,建立了单输入双输出动力学模型,并设计相应的定位实验。对原始实验数据进行离散数据插补和归一化处理,在实验数据和动力学模型的基础上,采用最小二乘法进行未知参数的辨识。采用基于ARX模型的系统辨识方法对内工作台系统进行辨识。两种辨识结果的对比显示,基于ARX模型的辨识结果与实际数据更加吻合,适合描述系统特性;而基于理论模型的辨识结果则更加贴近系统实际结构,对系统结构优化有指导意义。

In order to know the characteristics of a positioning stage,a dynamic model with single input and two-output was developed and the positioning tests were done.Based on the dynamic model and the test data after interpolating and normalizing,the unknown parameters were identified with the least square method.Another identification method based on an ARX model was applied to recognize the inside stage system.The results comparison indicated that the ARX model is appropriate to describe the characteristics of the stage system,while the dynamic model is meaningful for structural optimization.