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| 数控速度规划中的过象限摩擦误差约束 |
方晨曦1,张辉1,叶佩青1( ),梁文勇2,李维谦2 |
| 2. 甘肃省数控机床工程技术研究中心, 天水 741024 |
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| High-speed feed-rate planning with friction error constraints |
| Chenxi FANG1,Hui ZHANG1,Peiqing YE1(),Wenyong LIANG2,Weiqian LI2 |
1. Beijing Key Laboratory of Precision/Ultra-Precision Manufacturing Equipments and Control, Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China
2. Gansu Engineering Research Center for CNC Machine Tool, Tianshui 741024, China |
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| 文章导读 |
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摘要数控高速加工复杂轨迹时,过象限摩擦误差是轮廓误差的重要来源。将过象限摩擦误差约束加入速度规划模型,能有效弥补伺服系统中的摩擦力反馈补偿缺乏全局信息的缺陷,在保证加工精度的同时实现最优加工效率。首先建立了考虑摩擦影响的机床进给伺服系统动力学模型,结合数学推导与参数正交实验方法,针对光滑复杂轨迹研究了过象限摩擦误差产生机理,提出了系统换向时由摩擦产生的最大跟随误差的预测数学模型,并将其作为约束加入数控速度时间最优规划模型。实验结果表明: 该模型可以较为精确地预测过象限摩擦误差。对比轨迹跟踪结果证明了包含过象限摩擦误差约束的速度规划能有效控制最终轨迹轮廓精度。
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| 关键词 ：数控系统,进给速度规划,轮廓误差,摩擦误差 |
Abstract：Feed-rate planning models must be accurate to improve contouring performance and efficiency. Quadrant protrusion errors caused by friction forces are an important source of contour error in high-speed contouring of complex curves. A theoretical analysis is given here to describe the relationships among the curvature, feed rate and quadrant protrusion error. Then, experiments with a wide range of parameters are used to develop a friction error model for feed-rate planning with the friction error as a constraint. Tests show that the model can accurately estimate the friction error and guarantee the contour accuracy requirements.
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| Key words：numerical control systemfeed-rate planningcontour errorfriction error |
| 收稿日期: 2013-11-22 出版日期: 2015-03-17 |
| 基金资助:国家“十二五”科技重大专项(2011ZX04004-012) |
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