| 摘要: |
| 现有数控系统和伺服驱动系统开放性有限，实时轮廓误差控制策略难以实现，为避免加工设备二次开发，研究了精密加工轮廓误差的离线补偿方法，本文提出了一种以减少轮廓误差为目的的跟踪误差匹配方法。首先在构建各进给系统的机电混合控制模型的基础上，推导轮廓误差关于参考轨迹的灵敏度函数；然后以轮廓误差灵敏度函数为理论依据，针对数控加工过程中常用的G01直线和G02/G03圆弧指令，分析伺服参数在不同运动学参数下对加工轨迹的影响；最后通过调整各伺服轴的控制参数，匹配动态误差系数，提高轮廓精度。此方法可在不增加控制系统复杂性的同时减小各轴动态特性导致的误差，对提高多轴联动加工轮廓精度具有参考价值。 |
| 关键词: 轮廓误差 数控加工 灵敏度函数 运动控制 动力学匹配 |
| 基金项目: |
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| Study on Gain Matching Based on Contour Error Sensitivity Function |
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Jiang Jiali1, Dong Ronghua1, Zheng Tao1, Zhang Hui2, Lin Fuyan3
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1. Beijing Institute of Aerospace Control Devices, Beijing 100039;2. Department of Mechanical Engineering,
Tsinghua University, Beijing 100084;3. Department of Mechanical and Electrical Engineering,
China University of Mining & Technology (Beijing), Beijing 100083
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| Abstract: |
| The openness of existing computer numerical control systems is limited. And real-time contour error control strategies are difficult to integrate. For precision machining, it is necessary to work on off-line compensation methods for contour errors. In order to avoid secondary development of machining equipment, this paper proposes a method to reduce contour errors by matching the tracking error of each axis. Firstly, based on the construction of electromechanical hybrid control models for each feed system, the sensitivity function of contour error with respect to the reference trajectory is derived. Then based on the sensitivity function of contour error, the influence of servo parameters on the machining trajectory under different kinematic parameters is analyzed for the commonly used G01 line and G02/G03 arc commands in computer numerical control machining. Finally, by adjusting the control parameters of each servo axis and matching the dynamic error coefficient, the contour accuracy is improved. This method can reduce the errors caused by the dynamic characteristics of each axis without increasing the complexity of the control system. Meanwhile, this method has reference value for improving the contour accuracy of multi-axis synchronous machining |
| Key words: contour error computer numerical control sensitivity function motion control matched dynamics |
