Contouring control of Stewart Platform based machine tools
Contouring control of Stewart Platform based machine tools
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DOI：
10.23919/acc.2004.1384510
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
D. Garagic;K. Srinivasan
中科院分区：
文献类型：
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作者：
D. Garagic;K. Srinivasan
本文提出了两种新颖的鲁棒自适应笛卡尔空间控制算法，用于基于六自由度高性能斯图尔特平台的机床中的摩擦补偿。第一个控制器采用基于假定的参数线性摩擦模型的自适应摩擦补偿方案。所提出的摩擦补偿算法明确地考虑了随时间变化的法向力以及摩擦系数对速度的依赖性。 Stribeck 摩擦特性和变化的球形接头静摩擦被视为有界扰动，并由滑模鲁棒控制器进行补偿。在第二个控制器中，开发了一种新形式的 Takagi-Sugeno 多输入多输出模糊系统，用于自适应学习未知的摩擦行为并对其进行补偿。这种方法假设没有关于支柱接头摩擦效应的先验知识。仿真结果表明，当使用传统控制算法时，自适应控制器大大减少了速度反转时由摩擦引起的大轮廓误差。
In this paper, two novel robust adaptive Cartesian space control algorithms are proposed for friction compensation in the six degrees of freedom high performance Stewart Platform based machine tools. The first controller utilizes an adaptive friction compensation scheme based on a postulated linear-in-the-parameters friction model. The proposed friction compensation algorithm explicitly accounts for time varying normal forces as well as dependence of the friction coefficient on velocity. The Stribeck friction characteristic and varying spherical joint static friction are treated as bounded disturbances, and compensated by a sliding mode robust controller. In the second controller, a new form of Takagi-Sugeno multi-input multi-output fuzzy system is developed to adaptively learn unknown friction behavior and compensate for it. This approach assumes that no a priori knowledge about frictional effects in the strut joints is available. The simulation results indicate that large contouring errors caused by friction at the velocity reversals when conventional control algorithms are used, are reduced greatly by the adaptive controllers.