摘要
在高速运动中,Delta并联机器人杆件发生的弹性变形和振动对运动性能的影响不可忽略。针对有限元法离散柔性杆时出现方程维度高且难以适用于主动控制的问题,通过假设模态法和Kane方法,对Delta刚柔耦合并联机器人进行动力学建模。通过添加闭链刚柔耦合系统运动学位置、速度、加速度约束方程,建立了闭链形式的Delta并联机器人的刚柔耦合动力学方程。针对Delta并联机器人刚柔耦合动力学模型复杂度高的问题,利用奇异摄动法,将刚柔耦合动力学模型依据时间尺度分解为快变和慢变两个子系统。为避免扰动的影响并保证收敛性,针对慢变系统设计了非奇异终端滑模控制器;为抑制弹性振动对运动的影响,针对快变系统设计了LQR最优控制器,并将两个子系统的控制器合并为刚柔耦合系统的非线性混合控制器。仿真对比实验证明,所设计的混合控制器不仅保持了更高精度的轨迹跟踪,而且实现了明显的振动抑制效果,为Delta刚柔耦合并联机器人的主动跟踪控制和振动抑制提供了新思路。
In high-speed motion,the elastic deformation and vibration of the Delta parallel robot cannot be ignored,which have an impact on the motion performance.To address the problem of high equation dimensions and difficulty in being suitable for active control when discretizing flexible rods using finite element method,dynamic modeling of Delta rigid flexible coupled parallel robots was conducted using the assumed mode method and Kane method.By adding the position,velocity and acceleration constraint equations of the closed chain rigid flexible coupling system,the rigid flexible coupling dynamic equations of the closed chain Delta parallel robot are established.In order to solve the problem of high complexity of the rigid flexible coupling dynamic model of Delta parallel robot,the rigid flexible coupling dynamic model is decomposed into fast changing and slow changing subsystems according to the time scale by using the Singular perturbation method.In order to avoid disturbance and ensure convergence,a nonsingular terminal sliding mode controller is designed for slow varying systems.To suppress the influence of elastic vibration on motion,an LQR optimal controller was designed for fast changing systems,and merge the controllers of the two subsystems into a nonlinear hybrid controller of the rigid flexible coupling system.Simulation comparative experiments have shown that the designed hybrid controller maintains higher precision trajectory tracking and achieves significant vibration suppression effects,providing a new approach for active tracking control and vibration suppression of Delta rigid flexible coupled parallel robots.
作者
商德勇
黄云山
黄欣怡
潘崭
SHANG Deyong;HUANG Yunshan;HUANG Xinyi;PAN Zhan(School of Mechanical and Electronic Engineering,China University of mining and Technology(Beijing),Beijing 100083;Institute of intelligent Mining&Robotics,China University of mining and Technology(Beijing),Beijing 100083;Key Laboratory of Intelligent Mining and Robotics,Ministry of Emergency Management,Beijing 100083)
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2024年第5期95-106,共12页
Journal of Mechanical Engineering
基金
国家自然科学基金面上项目(52174154)
国家自然基金创新研究群体项目(52121003)资助项目。
关键词
并联机器人
刚柔耦合
假设模态法
KANE方法
奇异摄动
parallel robot
rigid flexible coupling
assumed mode method
Kane method
singular perturbation
