【作者】 史家顺；

【导师】 王宛山；

【作者基本信息】 东北大学 ， 机械制造及其自动化， 2016， 博士

【摘要】 随着工业自动化的快速发展,机器人技术正向高精度、高效率、智能化、工业化方向发展,具有诸多优点的混联机器人是现代工业机器装备中发展方向之一。混联机器人虽结构简单,但控制复杂,不同的机构,尺寸参数不同,导致了运动学位置逆解模型不同;而且混联机器人需要多轴联动控制,因此,混联机器人对其数控系统的控制准确性、实时性、开放性和灵活性要求高。研究开发一台混联机器人需要多种方案的反复比较及试验,也需要大量的技术投资和较长的开发周期。在相关研究的基础上,如何快速地进行机器人设计、精度分析和结构参数的识别以及运动控制技术的完善与性能的优化等,成为混联机器人亟待解决的关键技术问题。本文针对东北大学自主创新研制出的3-TPS混联机器人根据其自身的结构特点及五自由度空间运动的性能要求,通过采用数字样机等技术对混联机器人进行理论建模、仿真和实验综合分析,为其结构设计、精度分析及控制系统的实现和应用提供重要参考依据。全文的主要研究内容如下:(1)依据3-TPS混联机器人自身的结构特点及其五自由度空间运动的性能要求,建立该混联机器人的运动学数学模型,并确定工作空间范围,包括混联机器人的位置逆解推导,各结构参数与工作空间关系分析,以及有效工作空间的提出并对其影响参数的灵敏度进行了探讨。(2)针对混联机器人的电机参数选择和零件设计问题,采用数字样机技术仿真分析该混联机器人各主动杆件的速度、加速度和驱动力曲线,获得3-TPS混联机器人的运动和动力特性;通过CAE进行混联机器人关键部件静力学和模态分析,为机构优化设计提供参考依据。(3)针对3-TPS混联机器人的特点及运动功能要求,确定采用多轴运动控制器作为控制系统的核心,讨论运动学缓冲区和旋转运动缓冲区两种方式下混联机器人的位置控制方法;讨论其速度控制方法,为控制系统的设计奠定基础。(4)设计并搭建3-TPS混联机器人开放式数控系统硬件平台;开发控制系统软件平台和应用程序,主要包括:分析基于Clipper多轴运动控制器及其接口以及伺服单元接口电路原理,设计开放式数控系统硬件平台;规划混联机器人数控系统的软件平台结构,确定混联机器人运动控制原理和流程。开发含有运动学逆解的G代码解释程序和人机交互界面,实现混联机器人的数控系统的运动功能及辅助功能。(5)针对3-TPS混联机器人存在的主要结构误差进行运动学标定。分析杆长误差和铰链点位置误差对终端平台位姿的影响,建立结构误差标定数学模型。通过混联机器人标定实验,获得实验数据,再通过参数识别获得机器人的实际杆长和铰链点坐标,并将运动学方程中的实际结构参数代替理论参数,实验分析标定前后机器人运动精度改善情况。(6)开展了运动控制实验及切削加工实验。通过混联机器人四自由度水平面运动和五自由度空间加工实验,证明所构建的基于Clipper的3-TPS混联机器人控制系统是可行的,并验证混联机器人运动学逆解模型及运动程序的正确性。更多还原

【Abstract】 With the rapid advancement of industrial automation,the robots technology with high precision,high efficiency,intelligence and industrialization are the directions in developing modern robot technology.Moreover,the hybrid robot with many advances is considered as the direction in developing modern industrial machining equipments.Although the structure of hybrid robot is very simple,in the view of its complicated control method,various mechanisms and geometrical parameters resulting in the different inverse kinematics models.Because the hybrid robot is needed to be controlled by multi-axis linkage,the requirements in terms of accuracy,openness,flexibility and the character of real-time of its numerical control system are quite high.A hybrid robot is researched and developed by repeatedly comparable multi-scheme experiments with a lot of technical investments and a quite long development cycle.The key technologies of hybrid robots,in terms of rapid design,precision analysis,identification of structural parameters,improving the motion control technique and optimization of performance with the available technology,were considered and solved based on relevant researches.A theoretical modeling and comprehensive analysts with simulations and experiments was conducted by using numerical prototype according to the 3-TPS hybrid robot’s structure characteristics and task space with five-degree freedom developed by Northeastern University independently.Therefore,the digital prototype can provide significant references to hybrid robot’s structural design,precision analysis,control system implementation and feasibility for application.The main contents were shown as follows:(1)The hybrid robot’s mathematical kinematics model was built and the range of its task space was determined according to the 3-TPS hybrid robot’s structure characteristics and the requirement of five-degree freedom task space.The hybrid robot’s position inverse solution and analysis of the relationship between structural parameters and task space were also deduced in this paper.Moreover,the concept of effective task space was proposed and the effect of relevant parameters on its sensitivity was also investigated.(2)The curves of robot’s velocity,acceleration and force of the driving poles were obtained by hybrid robot’s kinematic and dynamic characteristics analysis based on the problems of its motor parameter selection and part design.The statics and modal analysis of the key assembly units using CAE technique was conducted.The analysis of hybrid robot’s overall and key components was deduced,which provides references for optimization design of the mechanism.(3)Multi axis motion controller was selected as the core component of 3-TPS hybrid robot’s control system,according to its characteristics and motion functions.Two different position control methods such as kinematic buffer and rotary motion buffer were discussed.Furthermore,the robot’s velocity control method has also been discussed.All the methods mentioned would provide the foundation of the design for control systems.(4)An open numerical control system hardware platform of 3-TPS hybrid robot was designed and built.And the software platform of control system and relevant applications was developed as well.Additionally,the theory applied to Clipper controller’s multi axis motion controller interfaces and servo-circuit was analyzed.The open numerical system hardware platform was designed.The structure of hybrid robot’s numerical system software platform was laid out.The theory and progress of its motion control was determined.The development of G-code program and man-machine interaction interface was conducted,which realizes the motion and auxiliary function of hybrid robot’s numerical system.(5)The calibration on errors in 3-TPS hybrid robot’s main structures was conducted.Moreover,the effect of errors existing in the length of bars and the positions of hinges on terminal platform poses was analyzed,according to which the mathematical model of errors in structural calibration was built.With the calibration experiment on hybrid robot,the experimental data were obtained.Furthermore,the actual length of bars in hybrid robot and its hinges’*coordinates can be acquired by means of parameter identification.Finally,by replacing theoretical structural parameters with actual ones in the kinematic equations,the comparison of robot’s motion precision with and without calibration can be conducted.(6)The motion control and machining experiments were conducted.Moreover,the 3-TPS hybrid robot’s control system was proven to be feasible based on Clipper controller and the validity of its kinematics inverse model and motion program was verified as well based on 4 degrees of freedom planar motion and 5 degrees of freedom space motion experiments.更多还原