【作者】 刘艳伟；

【导师】 孙茂相；

【作者基本信息】 沈阳工业大学 ， 控制科学与工程， 2005， 硕士

【摘要】 现代自动控制技术的进步,为科学研究和空间探索工作开辟了更为广阔的空间,拓展了靠人力所不能及的新科学事业。自20世纪90年代到现在,人类逐步实现了6～10km深海探测;实现了对太阳系金星、火星、木星及木卫星等天体的探测。 如果将机器人看作是一种能够扩展人类工作能力的有效工具,那么人类在认识和改造世界的过程中就不能没有机器人。在机器人应用领域中,移动机器人是一个重要分支,也是重要的发展方向,因此对移动机器人运动控制问题的研究,一直倍受关注。 首先,本文在深入、系统的分析了非完整系统和轮式移动机器人控制方法的现状后,综述了非完整约束轮式移动机器人鲁棒控制问题,并简要阐述了关于非线性系统、鲁棒控制以及线性矩阵不等式等相关技术。 由于非完整约束WMR运动学方程中约束条件的存在,使得在世界坐标系下的点镇定问题变得十分复杂。本文针对非完整约束移动机器人“纯滚动无滑动”这个约束条件,设计了一种在极坐标系下基于Lyapunov函数的全局渐进镇定控制器。该方法使约束条件不显含于运动方程中,通过光滑定常状态反馈控制律,实现平衡点的渐进镇定,使机器人可以镇定到任意点。 在此基础上,为克服不确定扰动给系统带来的影响,设计出一种H_∞鲁棒控制器。严格来讲机器人运动系统既是非线性的,同时又存在各种不确定性扰动。往往正是因为这些不确定的扰动变量,使得对机器人系统的控制效果不能令人满意。本文采用LMI方法设计出一种H_∞观测器型控制器。该控制器对系统的不确定扰动有很强的鲁棒性。 最后,用MATLAB工具软件对前面所述两种控制器进行了仿真实验。仿真结果验证了文中所用方法的合理性和有效性。更多还原

【Abstract】 The progress of the modern automatic control technology provides even wider space for scientific research and exploration work. If the robot can be regarded as a kind of effective tool that expand the human ability to work, the manlcind can’t have no robot during the process of understanding and rebuilding the world. In the robot application, the mobile robot is an important domain of it, and it has been an important development direction too. The research on the control of mobile robot, been paid extremely attention all the time.First of all, under analysising current situation of nonholonomic system and the wheeled mobile robot control method in deepen, systematic, this dissertation summarize the robust control of WMR with nonholonomic constraints, and has explained relevant technology , such as non-linear system, robust controlling and linear matrix inequality ,etc. briefly .Because of restriction terms of nonholonomic constraint WMR kinematics equation, point stabilization become very complicated under Cartesian coordinates. This dissertation aim at the constraint condition that" pure roll without slippage ", designed an asymptotically stabilizing controller based on Lyapunov function under polar coordinates. This method restrained constraint condition from to be apparent to include among the equation, made it is possible that WMR system can be stabilized to any given place.On this basis, a kind of H_∞ robust controller has been design. Observer-based controller is widely accepted for its simple structure and esplicit physical meaning. The LMI method todesign H_∞ controller under the assumption of observer-based type is studied.Finally, the simulation results show the effectiveness of the proposed control method.更多还原