一种新型3-RRPU并联机构的运动学及鲁棒控制研究  

Kinematics and robust control of a novel 3-RRPU parallel mechanism

作　　者：韩秀英[1] 李旭莹 凌金博 杨琨 HAN Xiuying;LI Xuying;LING Jinbo;YANG Kun(School of Mechatronics Engineering,Henan University of Science and Technology,Luoyang 471003,China)

机构地区：[1]河南科技大学机电工程学院,河南洛阳471003

出　　处：《机电工程》2024年第8期1464-1471,共8页Journal of Mechanical & Electrical Engineering

基　　金：河南省自然科学基金资助项目(182300410273)。

摘　　要：针对现有的三平移并联机构大多正解不唯一、较难实现精确稳定运动控制的问题,提出了一种新的3-RRPU型三平移并联机构,同时研究了机构的运动学、动力学及轨迹跟踪控制方法。首先,运用螺旋理论分析了该机构三平移的原理,进行了驱动输入的选取与论证,对机构平台奇异性、驱动奇异性和支链奇异性进行了分析;其次,运用运动学理论建立了运动学模型,推导了位置正、逆解析解;再次,运用拉格朗日动力学理论建立了机构操作空间的刚体动力学模型;最后,提出了一种基于非线性反馈解耦的自适应滑模轨迹跟踪控制方法,以证明其控制稳定性,并基于动力学模型对空间轨迹跟踪精度和控制力矩进行了仿真分析。研究结果表明:3-RRPU并联机构的位置正解在一般位形下具有唯一性,机构的平台奇异位形和驱动奇异位形少且无支链奇异。该轨迹控制方法可使机构在载荷20 kg、速度0.18 m/s、加速度0.12 m/s 2下,实现0.002 m以内的高精度复杂轨迹跟踪;基于Sigmoid函数的轨迹控制方法还能有效削弱控制力矩的抖振,为实现工业领域高速、高精度、高性能的三平移运动提供了新方法。Most of the existing three-translation parallel mechanisms have more than one forward solution and are difficult to achieve precise and stable motion control.Therefore,a novel 3-RRPU parallel mechanism with three translational degrees of freedom was proposed,and the kinematics and dynamics and trajectory tracking control method of the parallel mechanism was researched.Firstly,by using the screw theory,the mechanism principle of implementing three translations was analyzed,and the drive input joints were chosen and demonstrated,and the characteristics of platform singularity,drive singularity,and branch-chain singularity of the parallel mechanism were analyzed.Secondly,the kinematics model of the parallel mechanism was built with the kinematics theory,and the forward and inverse position analytic solutions were derived.Thirdly,by using the Lagrange s dynamics theory,the rigid-body dynamics model of the parallel mechanism within the operating space was set up.Finally,a nonlinear feedback decoupled adaptive slide-mode trajectory tracking control method was proposed,and the stability of the trajectory control method was proved,based on the dynamics model of the parallel mechanism,the accuracy and drive moment simulations of the trajectory tracking control were implemented.The research results show that the mechanism has unique analytic forward position under general space configuration,and there are very few of the platform and drive singularity configurations of the mechanism and there is no branch-chain singularity configuration.The proposed trajectory tracking control method can enable the mechanism to achieve high-precision complex trajectory tracking of 0.002 m under a load of 20 kg,a speed of 0.18 m/s,and an acceleration of 0.12 m/s 2,and especially,the trajectory tracking control method based on the Sigmoid function can effectively weaken chattering of the control moment,which provides new method for the implementation of three translational motions of high-speed,high-precision,and high-performance in the indu

关 键 词：三平移并联机构 位置正解 奇异性 螺旋理论 非线性反馈解耦 自适应滑模轨迹跟踪控制方法 机构操作空间 

分 类 号：TH112[机械工程—机械设计及理论]