【作者】 王卫东；

【导师】 陈光达；

【作者基本信息】 西安电子科技大学 ， 机械电子工程， 2007， 硕士

【摘要】 基于新一代大射电望远镜光机电一体化创新设计方案,围绕“馈源指向系统高精度轨迹跟踪要求”,鉴于并联机器人所具有的高刚度、高精度、高负载能力等特点,本文采用一种称为Stewart平台的并联机器人作为系统的精调平台。以精调Stewart平台为对象,研究了其机构及运动学逆解、控制策略及控制算法,并基于嵌入式控制技术设计了平台的控制系统。Stewart平台是一种6自由度的并联机器人,本文分析了平台的机构及运动学逆解,对平台的控制策略进行了研究,确定了平台基于关节式的计算机分布式控制策略。针对Stewart平台的系统要求,从工程实际出发设计了一种基于关节式计算机分布式控制策略的非线性PID的关节调节器。该非线性PID算法构造了增益参数关于误差信号的非线性拟合函数,算法能够同时保证响应速度快、超调量小以及自适应能力强的系统特性。通过建立平台的数学模型,进行了典型信号输出响应数值仿真。仿真结果验证了关节空间控制策略以及非线性PID控制方法的可行性和有效性。基于并联机器人运动控制技术,采用计算机实现的伺服电机位置闭环控制,设计了ARM+DSP结构的嵌入式控制系统;并规划了控制系统的软件与硬件系统。Stewart嵌入式控制系统达到了控制精度高、可靠性好和实时性强的系统要求,同时解决了Stewart平台工作空间有限的问题。更多还原

【Abstract】 Based on a completely new design project of next generation large radio telescope (LT) integrating mechtronics and optics technologies, for the high requirement of trajectory tracking of the feed-supporting system with large span cables, considering the high rigidity, the high precision and the high ability of load, one kind of Parallel Robot named Stewart platform was adopted by the fine tuning of LT. The Stewart platform is considered as a plant in this paper, inverse problems, the framework on Kinematics of fine tuning Stewart platform and the control strategy is analyzed. And based on the edbedded control technology, the control system of the platform is designed.Stewart platform is one kind of six degrees-of-freedom(DOF) Parallel Robot. The mechanism analysis of the High-precision Tracking Control of the Stewart Platform is deduced. The distributed control strategy is adopt in the joint space, and the double servo control sub-systems involving position control and velocity control is designed. For the system need of the Stewart platform, a kind of nonlinear PID linkspace controller is designed considering the project fact. The nonlinear function is given by the nonlinear PID algorithm, and the algorithm can guarantee the system have the property of the fast response, a little over shot and strong self adaptive.The model of the platform is constrated, and simulation of the typical signal output response is done. The effectiveness and feasibility of the linkspace control strategy and the non-linear PID controller are verified by the analyses and the results of the emulaton.Based on the motion control technology of the parallel robot, the position closed loop control system realized by the computer system is adopted. And the embedded control system of ARM+DSP architecture is adopted, which can guarantee the system have the property of high control precision, the high reliability and the strong realtime performance. And the embedded control system can solve the problem of the limit work place of the Stewart platform. The software and hardware of the embedded control system is also designed.更多还原