凿岩机械臂轨迹规划及电液跟踪控制研究

Study on trajectory planning and electro-hydraulic tracking control of rock drilling manipulator

针对液压凿岩机械臂运动控制的平稳性及跟踪精度问题,提出一种关节空间轨迹规划和电液系统模糊PID跟踪控制方法。首先,基于关节空间五次多项式插值方法对关节的位置、角速度及角加速度进行约束,生成含有时间序列的关节角度变量,通过直接控制关节角度完成轨迹规划。采用智能算法模糊PID对液压缸位移进行跟踪控制,将传感器反馈并计算得到的位移偏差值及其变化率作为模糊控制器的输入,经模糊处理后,把输出的3个参数ΔK_(P)、ΔK_(I)、ΔK_(D)加到PID控制器中以此实现动态调参。在V-REP(Virtual-Robot Experimentation Platform)中建立三维SolidWorks的虚拟样机模型,使用MATLAB软件远程API同步模式控制V-REP验证所提轨迹规划方法对工程实际机械臂的有效性。同时,通过模糊工具箱设计模糊控制器并运用Simulink模块对电液跟踪控制系统进行仿真。V-REP及Simulink仿真结果表明:五次多项式轨迹规划可避免机械臂运动过程中速度及加速度的突变,V-REP中机械臂模型运行平稳;模糊PID能有效提高电液系统的跟踪控制精度,系统响应快速,上升时间不到2 s,最大跟踪误差不超过3.3 mm,该结果可满足凿岩机械臂实际施工作业时规定的误差要求。

Aiming at the problems of stationarity and tracking accuracy of hydraulic rock drilling manipulator,a method of joint space trajectory planning and fuzzy PID tracking control of electro-hydraulic system was proposed.Firstly,the joint position,angular velocity and angular acceleration were constrained based on the joint space quintic polynomial interpolation method,and the joint angle variables containing time series were generated,and the trajectory planning was completed by directly controlling the joint angle.The intelligent algorithm fuzzy-PID was used to track and control the displacement of hydraulic cylinder.The displacement deviation value and its change rate obtained from sensor feedback were used as the input of fuzzy controller.After fuzzy processing,the output parametersΔK_(P),ΔK_(I)andΔK_(D)were added to PID controller to realize dynamic parameter adjustment.These enterprises establish a 3D SolidWorks virtual prototype model in V-REP(Virtual Robot Experimentation Platform),and use MATLAB remote API synchronous mode to control V-REP to verify the effectiveness of the proposed trajectory planning method on the actual engineering manipulator.At the same time,the fuzzy controller was designed by fuzzy toolbox and Simulink module was used to simulate the electro-hydraulic tracking control system.The simulation results of V-REP and Simulink show that the mutation of the velocity and acceleration of the manipulator can be avoided by the fifth-degree polynomial trajectory planning,and the manipulator model runs smoothly in V-REP.Fuzzy PID can effectively improve the tracking control accuracy of electro-hydraulic system,the system response is fast,the rise time is less than 2 s,and the maximum tracking error is not more than 3.3 mm.This result can meet the specified error requirements for the actual construction operation of the drilling manipulator.