多自由度机械臂控制算法设计..

摘要

机器人是一种能够进行编程并在自动控制下执行某些操作和移动作业任务的机械装置。而机械臂作为机器人最主要的执行机构，是一个十分复杂的多输入多输出非线性系统,它具有时变、强耦合和非线性的动力学特征，因其控制的复杂性引起了相关从业人员的广泛关注。随着时代的进步，像军事制造、工业生产、日常生活及教育娱乐等各个领域对机器臂控制技术应用需求逐渐加大，从而使得设计一套工作空间大，运动灵活的多自由度机器臂尤为重要。

机械手臂运行轨迹追踪控制技术有包括：adaptive control(自适应控制)、smvsc(滑模变结构控制)、Robust adaptive control(鲁棒自适应控制)、Fuzzy adaptive(模糊自适应）等四大类。本文主要运用模糊PID控制设计二自由度机械臂控制算法，该控制方法具有模糊控制灵活和适应性强的优点，也具有经典PID控制精度高的特点。

本文围绕二自由度机械臂控制算法设计，首先建立二自由度关节型机械臂的数学模型，即二自由度机械臂输入驱动力矢量和输出转动角度矢量之间的函数关系。然后运用模糊PID控制设计一套机械臂轨迹规划算法，能够根据使用者的作业任务要求，求出二自由度机械臂终端执行器的轨迹。并研究如何对于给定的系统设计出PID控制器，实现控制系统的输出对参考输入跟踪，以及对扰动输入响应具有较小的振幅，且能够衰减到零即无稳态误差。最后给出了基于MATLAB/SIMULINK软件的案例分析,阐释模糊PID控制算法行之有效性。

关键词:多自由度，机械臂，PID算法控制，数学模型

Abstract

Robot is a kind of programming and perform certain operations and mobile task mechanism in automatic control. And robot arm as the main executive body, is a very complex multi input and multi output nonlinear system, it has a time-varying, strong coupling and nonlinear dynamic characteristics, due to the complexity of the control caused wide attention of practitioners. With the progress of the times, like military manufacturing, industrial production, daily life and entertainment, education and other fields of a robot arm control technology application requirements gradually increase, from the design a large working space, the flexible movement of the multi degree of freedom robot arm is particularly important.

Mechanical arm trajectory tracking control technology including: adaptive control, SMVSC, robust adaptive control, fuzzy adaptive etc.. In this paper, the use of fuzzy PID control design for two degree of freedom manipulator control algorithm, the control method with fuzzy control of a flexible and adaptable advantages, also has the classic PID control the characteristics of high precision.

This paper focuses on the design of control algorithm of two degrees of freedom manipulator, a mathematical model of two-DOF Manipulator, namely two-DOF Manipulator driving force and rotation angle between the output function. Then use the control to design a manipulator trajectory planning arithmetic of fuzzy PID method, according to the user's task requirements and for two degrees of freedom manipulator end effector trajectory. And study how to design a system for PID controller is given, to achieve the output of the control system of the reference input tracking, and disturbance input response amplitude is smaller, and can decay to zero no steady state error. Finally, a case analysis based on MATLAB/SIMULINK software is presented to illustrate the effective of PID fuzzy control algorithm.

Key Words: Multi degree of freedom, manipulator, control, PID algorithm, mathematical mode