标题： 机械系统中无速度测量的非线性摩擦自适应补偿 显示英文标题

标题： Adaptive Compensation of Nonlinear Friction in Mechanical Systems Without Velocity Measurement

摘要： 摩擦是一种在所有包含相对运动部件的机械系统中不可避免的现象。众所周知，摩擦是精确伺服控制的一个严重障碍，因此人们一直有兴趣设计一种补偿它的方法——这一主题多年来一直受到许多研究人员的关注。文献中报道的大多数摩擦补偿方案都依赖于速度测量的可用性，而这种信息很难获得。现有方法的第二个限制是它们依赖于包含多个未知参数的摩擦数学模型，其中一些参数以非线性方式进入动态方程。在本文中，我们为受到静态和库仑摩擦扰动的机械系统提出了一种全局收敛的跟踪控制器，这是一种可靠的摩擦现象数学模型，不需要速度测量。关键组件是一个基于浸入和不变性的自适应速度观测器，用于摩擦补偿。据我们所知，这是对该挑战性问题的第一个全局收敛解决方案。我们还展示了我们的观测器在受摩擦影响的系统中的应用仿真结果，这些系统由更先进的LuGre模型描述。 显示英文摘要

摘要： Friction is an unavoidable phenomenon that exists in all mechanical systems incorporating parts with relative motion. It is well-known that friction is a serious impediment for precise servo control, hence the interest to devise a procedure to compensate for it -- a subject that has been studied by many researchers for many years. The vast majority of friction compensation schemes reported in the literature rely on the availability of velocity measurements, an information that is hard to obtain. A second limitation of the existing procedures is that they rely on mathematical models of friction that contain several unknown parameters, some of them entering nonlinearly in the dynamic equations. In this paper we propose a globally convergent tracking controller for a mechanical system perturbed by static and Coulomb friction, which is a reliable mathematical model of the friction phenomenon, that does not rely one measurement of velocity. The key component is an immersion and invariance-based adaptive speed observer, used for the friction compensation. To the best of our knowledge, this is the first globally convergent solution to this challenging problem. We also present simulation results of the application of our observer for systems affected by friction, which is described by the more advanced LuGre model.