摘要
Because of its ease of implementation,a linear PID controller is generally used to control robotic manipulators.Linear controllers cannot effectively cope with uncertainties and variations in the parameters;therefore,nonlinear controllers with robust performance which can cope with these are recommended.The sliding mode control(SMC)is a robust state feedback control method for nonlinear systems that,in addition having a simple design,efficiently overcomes uncertainties and disturbances in the system.It also has a very fast transient response that is desirable when controlling robotic manipulators.The most critical drawback to SMC is chattering in the control input signal.To solve this problem,in this study,SMC is used with a boundary layer(SMCBL)to eliminate the chattering and improve the performance of the system.The proposed SMCBL was compared with inverse dynamic control(IDC),a conventional nonlinear control method.The kinematic and dynamic equations of the IRB-120 robot manipulator were initially extracted completely and accurately,and then the control of the robot manipulator using SMC was evaluated.For validation,the proposed control method was implemented on a 6-DOF IRB-120 robot manipulator in the presence of uncertainties.The results were simulated,tested,and compared in the MATLAB/Simulink environment.To further validate our work,the results were tested and confirmed experimentally on an actual IRB-120 robot manipulator.
由于线性PID控制器易于实现,一般采用其对机器人进行控制。线性控制器不能有效地处理不确定性和参数的变化,因此推荐具有鲁棒性能的非线性控制器。滑模控制(SMC)是一种针对非线性系统的鲁棒状态反馈控制方法,其设计简单,有效地克服了系统中的不确定性和扰动,它的瞬态响应非常快,是理想的控制器。SMC最主要的缺点是控制输入信号的抖动。为了解决这一问题,本文采用SMC与边界层(SMCBL)相结合的方法,消除了系统的抖振现象,提高了系统的性能。将所提出的SMCBL与传统的非线性控制方法逆动态控制(IDC)进行了比较。首先,对IRB-120机器人机械手的运动学方程和动力学方程进行了完整、准确的提取;然后,对采用SMC的机器人机械手的控制进行了评价。为了验证该控制方法的有效性,在一个6自由度IRB-120机器人机械手上使用了该控制方法。在MATLAB/Simulink环境下对仿真结果进行了仿真、测试和比较。为了进一步验证我们的工作,在一个实际的IRB-120机器人机械手上进行了测试和实验验证。
作者简介
Corresponding author:Mojtaba HADI BARHAGHTALAB,PhD Candidate;Tel:+98–71–36260232;E-mail:mh.barhaghtalab@gmail.com;ORCID:0000-0002-2571-3723
