【作者】 刘丹；

【导师】 刘昕晖； 白笃；

【作者基本信息】 吉林大学 ， 机械工程（专业学位）， 2020， 硕士

【摘要】 挖掘机作为一种重要的土石方施工机械,广泛应用于建筑、采矿、石油、军事工程等领域。为了提高挖掘机的工作效率降低操作人员的工作强度,国内外各个主机厂开始积极提升挖掘机的智能化水平,将电子控制技术应用于挖掘机,逐渐形成了挖掘机智能控制体系,这对国民经济的发展有着重要的意义。本文来源于校企合作项目“FW80液压挖掘机的设计开发”(项目编号:FW/RD201717),重点研究挖掘机工作装置轨迹控制系统,当已知目标点坐标时对工作装置的运动轨迹进行有效控制,为实现挖掘机的智能化奠定基础。本文应用的技术包括机器人技术、电液比例技术、控制技术等,通过理论分析、模型搭建、样车实验及联合仿真对系统进行研究,本文的研究内容包括以下几个方面:通过查阅大量相关文献,对挖掘机的智能化发展概况及电液比例技术进行了简单介绍。并对现阶段国内外挖掘机智能化研究现状,以及国内外各个主机厂的主流产品进行了总结。对本项目所采用的负载独立流量分配系统进行理论分析及动态特性分析,在原有系统的基础上进行优化,用电控手柄代替原系统的液控先导手柄,并在工作装置各个回路添加电液比例减压阀,完成电控系统的设计并对主要元件进行选型。根据机器人技术建立挖掘机工作装置的D-H坐标,通过对挖掘机工作装置的正、逆运动学分析,得到铲斗齿尖坐标、各关节转角、各油缸伸缩量的相互转换关系。为了保证所规划的运动轨迹是一条光滑的曲线,且运动过程中的速度和加速度连续变化,本文采用五次多项式插值方法对运动轨迹进行优化。采用AMESim软件搭建了负载敏感变量泵、多路阀、电液比例减压阀及工作装置液压系统的仿真模型,对仿真模型进行仿真分析,验证所建立模型的正确性。根据实际研究需要,以课题组所研发的挖掘机作为实验样机,设计了相关实验,通对实验曲线与仿真曲线的对比分析,进一步验证了所建立的工作装置液压系统模型的正确性。针对普通PID控制性能的不足,本文分别采用遗传算法和粒子群算法优化PID参数,采用MATLAB/Simulink搭建其控制系统模型,并通过AMESim与MATLAB联合仿真平台对其进行仿真分析,仿真结果表明,采用粒子群算法优化PID参数具有更好的控制效果。更多还原

【Abstract】 Hydraulic excavator is an important construction machine,widely used in construction,mining,petroleum,military engineering and other fields.In order to improve the working efficiency of the excavator and reduce the working intensity of the operators,many manufacturers at home and abroad have begun to actively improve the intelligent level of the excavator and apply electronic control technology to the excavator,gradually forming an intelligent control system for the excavator.This has important meaning to the development of national economyThis paper is derived from the school-enterprise cooperation project "design and development of FW80 hydraulic excavator"(project number: FW/RD201717),focusing on the research on the trajectory control system of the excavator working device,realizing the effective control of the movement of the working device under the premise of known target coordinates,and laying a foundation for realizing the intellectualization of the excavator.The technologies applied in this paper include robot technology,electro-hydraulic proportional technology,control technology,etc.The system is studied through theoretical analysis,model building,sample vehicle experiment and joint simulation.This paper includes the following aspects:Through consulting a large number of relevant literature,this paper summarizes the general situation of intelligent development of excavator and electro-hydraulic proportional technique.At the same time,the research status of intelligent excavator at home and abroad and the mainstream products of each main engine factory are summarized.This project adopted load independent flow distribution(ludv)system through theoretical analysis and the dynamic characteristic analysis,on the basis of the original system,electric control optimization,use electric control handle instead of the original system of hydraulic control handle,and in each circuit working device to add a pair of electric proportional pressure reducing valve,complete the design of the electric control system and the selection of main components.According to the robot technology,the d-h coordinate of the working device is established.Through the analysis of the positive and inverse kinematics of the working device of the excavator,the mutual conversion of the driving space,the position and attitude space of the bucket teeth and the joint Angle space of the excavator working device are obtained.In order to ensure that the trajectory is a smooth line segment and that the velocity and acceleration change continuously in the process of motion,cubic polynomial interpolation and quintic polynomial interpolation are proposed and analyzed theoretically.Using AMESim software set the load sensitive variable pump,multi-way valve,electro-hydraulic proportional pressure reducing valve and the system simulation model,simulation analysis was carried out on the simulation model,according to the actual research needs,to research the development of the excavator as the prototype,the relevant program is designed,through comparing and analyzing the simulation data and experimental data was provided to verify the correctness of the established working device hydraulic system model.In view of the shortcomings of ordinary PID control effect,this paper adopts genetic algorithm and particle swarm optimization algorithm to optimize PID parameters,adopts MATLAB/Simulink to build its control system model,and through the AMESim and MATLAB joint simulation platform to carry out simulation analysis,simulation results show that using particle swarm optimization PID parameters optimization has better control effect.更多还原