基于PID控制策略的机械臂轨迹跟踪控制
Robotic Arm Trajectory Tracking Control Based on PID Control Strategy

关节机器人的轨迹跟踪控制，是指对各关节给定力矩驱动机器人的关节角、角速度等运动学参数跟踪给定的期望值，使机器人各关节能够获得期望的轨迹。在一般的仿真实验中，通常使用机械臂动力学方法来构建机械臂的数学模型。但受机械臂的不确定性以及测量误差等因素的影响，构建的机械臂数学模型往往不够精准，导致仿真实验结果不够精准。本文针对ABB-IRB120型号六自由度关节机械臂的轨迹跟踪控制问题进行研究。首先建立六自由度关节机械臂的D-H参数，并根据机械臂连杆链接关系制作ABB-IRB120型号六自由度关节机械臂的可视化模型。介绍PID控制的基本原理，并基于MATLAB软件中Simulink平台基于PID控制算法对六自由度关节机械臂进行轨迹跟踪的可视化仿真实验。根据仿真实验结果存在的跟踪效果不够完美的问题，提出并设计滑模PID控制器，基于改进的PID控制器对六自由度关节机械臂进行轨迹跟踪的可视化仿真实验，得出改进的PID控制器具有快速的响应、良好的稳定性和控制精度等特点。
The trajectory tracking control of the joint robot refers to the given torque of each joint to drive the joint angle, angular velocity and other kinematic parameters of the robot to track the given expected value, so that each joint of the robot can obtain the desired trajectory. In general simulation experiments, the mechanical arm dynamics method is usually used to construct the mathematical model of the manipulator. However, affected by factors such as the uncertainty of the manipulator and the measurement error, the mathematical model of the manipulator constructed is often not accurate enough, resulting in inaccurate simulation results. This paper studies the trajectory tracking control problem of the ABB-IRB120 six-degree-of-freedom joint manipulator. Firstly, the D-H parameters of the 6-DOF joint manipulator are established, and the visual model of the ABB-IRB120 6-DOF joint manipulator is made according to the link relationship of the manipulator. The basic principle of PID control is introduced, and a visual simulation experiment of trajectory tracking of a six-degree-of-freedom joint manipulator based on the PID control algorithm on the Simulink platform in MATLAB software is introduced. According to the problem that the tracking effect is not perfect in the simulation experiment results, a sliding mode PID controller is proposed and designed. Based on the visual simulation experiment of trajectory tracking of the six-degree-of-freedom joint manipulator based on the improved PID controller, the improved PID controller is obtained. It has the characteristics of fast response, good stability and control precision.