平面二自由度冗余驱动并联机器人控制实验研究

对平面二自由度冗余驱动并联机器人进行了逆运动学分析,由末端执行器的位置计算得到主动关节角的位置.分别采用传统的PID控制方法和PID+速度前馈补偿+加速度前馈补偿的方法对并联机器人轨迹跟踪问题进行了实验研究.通过比较2种控制方法的轨迹跟踪效果和比较由连接在连杆上的加速度传感器测量的振动大小,证明了PID+速度前馈补偿+加速度前馈补偿的方法能更好地实现轨迹跟踪.     

Optimal posture searching algorithm on mobile welding robot

An independently developed mobile welding robot system is introduced. Kinematics model is the base of robot planning. With the Denavit-Hartenberg method, robot kinematics equation can be gotten. The robot welding torch inclination angle consists of the working and moving angles. According to the kinematics model, both the two angles and torch position can be calculated. Under special moving angle, a two-step algorithm is used to obtain the optimal manipnlator posture. The calculation result shows that the Mgorithm has high precision.     

碰撞前车速计算误差的成因及处理方法

为准确计算汽车碰撞事故碰撞前车速,基于动量守恒定理的汽车碰撞事故模型,在事故分析中采用反推法求解. 根据事故现场勘查信息,应用运动学公式计算碰撞后车速,再将碰撞后车速代入模型计算碰撞前车速. 以实车碰撞试验对模型计算结果进行检验后,发现用模型计算的碰撞前车速存在误差. 为此以实车碰撞试验为对象,根据模型的求解过程和误差的传递过程,研究了碰撞前车速误差的成因和处理方法,以提高交通事故分析的准确性. 首先,应用矩阵理论研究了碰撞前车速误差的形成原因;其次,应用反推迭代算法建立了碰撞前车速误差的处理方法;最后,通过实例应用验证了该方法的可行性. 研究结果和实例应用表明:用运动学公式计算碰撞后车速所产生的误差是造成碰撞前车速误差的决定性原因,只需对碰撞后车速误差进行简单的1次处理就能使应用该模型计算碰撞前车速所产生的误差归0.      

Inverse Kinematics Analysis of Weld Inspection Manipulator at Pipe Joint in Nuclear Industry

A redundant manipulator that can online clamp pipe was developed to track along a cylinder intersection curve. With an ultrasonic transducer mounted on its end-effector, the manipulator can perform welding seam inspection at pipe joint in nuclear industry. An inverse kinematics solution expressed in joint space was solved based on the combination of geometric method and D-H matrix transformation. Expression about joints variables was obtained based on the scanning parameters of pipeline. The analysis method and results can be widely applied for online trajectory planning of intersection curve scanning manipulators.     

Kinematics Modeling of an Omnidirectional Autonomous Mobile Robot with Castor Wheels

The kinematics model of an omnidirectional wheeled mobile robot （WMR） platform with 3 castor wheels was built, which includes the actuated inverse solution and the sensed forward solution. Motion simulations verify the consistency between the actuated inverse solution and the sensed forward solution. Analysis results show that the WMR possesses 3 degrees of freedom, and its motion trajectory is a straight line. The ＂pushing＂ and ＂pulling＂ motion patterns of the WMR can be generated by using different wheel orientations. It can be used in the places where the space is limited.     

A new solution to the inverse position analysis of the redundant serial robot

A new solution to the inverse position analysis of the redundant serial robot is presented. The inverse position analysis problem of the redundant serial robot is transformed into a minimization problem and then the optimization method is adopted to solve the nonlinear least square problem with the analytic form of a new Jacobi matrix. In this way, the inverse solution of the redundant serial robot can be searched out quickly under the desired precision when the positions of the three non-collinear end effector points are given. The inverse position analysis of the 7R redundant serial robot is illustrated as an example and the simulation results verify the efficiency of the proposed algorithm.     

Development of a Robotic Cochlear Implantation System

Traditional cochlear implantation surgery has problems such as high surgical accuracy requirement and large trauma,which cause the difficulty of the operation and the high requirements for doctors,so that only a few doctors can complete the operation independently.However,there is no research on robotic cochlear implantation in China.In response to this problem,a robotic cochlear implantation system is proposed.The robot is controlled by robot operating system (ROS).A simulation environment for the overall surgery is established on the ROS based on the real surgery environment.Through the analysis of the kinematics and the motion planning algorithm of the manipulator,an appropriate motion mode is designed to control the motion of the manipulator,and perform the surgery under the simulation environment.A simple and feasible method of navigation is proposed,and through the model experiment,the feasibility of robotic cochlear implantation surgery is verified.     

STATICS ANALYSIS AND OPENGL BASED 3D SIMULATION OF COLLABORATIVE RECONFIGURABLE PLANETARY ROBOTS

In the last few years,based on the wide rangeof application domains,multirobot coordination be-came one of the focuses of robotics.M.B.Dias andA.Stentz[1]described a market-based architecturefor coordinating a group of robots to achieve a givenobjective.Terry Huntsberger,Paolo Pirjanian,Pir-janian,Ashitey Trebi-Ollennu,etc,have developedan enabling distributed control architecture calledcontrol architecture for multirobot planetary out-posts(CAMPOUT)[2].CAMPOUT includes thenecessary …     

Real-Time Discrete Adaptive Control of Robot Arm Based on Digital Signal Processing

A discrete model reference adaptive controller of robot arm is obtained by integrating the reduced dynamic model of robot, model reference adaptive control (MRAC) and digital signal processing (DSP) computer system into an electromechanical system. With the DSP computer system, the control signal of each joint of the robot arm can be processed in real time and independently. The simulation and experiment results show that with the control strategy, the robot achieved a good trajectory following precision, a good decoupling performance and a high real-time adaptivity.     

基于六自由度平台的轨道扭曲不平顺几何信息模拟

为了获取轨道扭曲不平顺几何信息,根据扭曲不平顺变化特征及轨道扭曲不平顺模拟器结构,建立了轨道不平顺模拟器双六自由度模拟平台位姿反解模型和位姿关联模型.借助Simulink位姿反解模型对国内常用轨距与转向架常用轴距对应的3种扭曲不平顺位姿反解进行解算,解算结果与位姿正解具有很好的一致性,验证了所建位姿反解模型、位姿协调关联模型的正确性.以某型转向架为例,利用试验台进行了不同基长的扭曲不平顺室内试验,研究了扭曲不平顺基长对轮重减载率的影响.试验结果表明,扭曲不平顺基长越小,轮重减载率越大,基长2.4、5.0 m的最大轮重减载率分别为0.594和0.581,满足国家标准规定的安全限值.      

A dynamic model of an underwater quadruped walking robot using Kane’s method

In this paper, the kinematics and dynamics of an underwater quadruped walking robot were derived based on Kane dynamic equations. This methodology allows construction of the dynamic model simply and incrementally. The velocity and angular velocity components of an underwater quadruped walking robot were served as the generalized velocities. The forces which contribute to dynamics of an underwater quadruped walking robot were determined by Kane＇s approach. The equations of hydrodynamic forces of an underwater quadruped walking robot were deduced. Hydrodynamic coefficients were determined by experiments. The dynamic model was established by obtaining the generalized active forces and the generalized inertia forces. Numerical simulations of the walking behavior on underwater flat ground were implemented to verify the dynamic model of an underwater quadruped walking robot. Simulation results show that the dynamic model is correct.     

履带式推土机尾扬头陷和头扬二工况下△Yr之探求

运用探求△Yr（推土机铰点O每区间末在纵向垂直偏离本区间台车架基线之数量）的基本思路,分别研究了履带式推土机尾扬头陷和头扬工况下的△Yr,导出了二种工况下△Yr的表达式;利用铲刀纵前向运动的履带式推土机模型对二工况下克服后扰及β型扰动分别进行了物理仿真．研究结果表明：在这二种工况下,无论本区间内履带下地形如何,自控系统可根据各工况下导出的△Yr表达式及铲刀刃纵倾轨迹角αc的控制公式克服履带下地形的扰动,使αc最终等于期望的铲刀刃纵倾轨迹角α′．仿真结果证实了导出的△Yr表达式正确,使αc的控制公式在这二种工况下的应用上迈出了关键的一步．     

六自由度重载装配机械手运动学分析及求解

针对汽车装配生产线作业对重载高精度的自动设备的需求,设计了一种液压驱动的六自由度多功能重载装配机械手。运用Denavi-Hartenberg(D-H)方法构建了机械手的运动学模型,分析了重载装配机械手的工作原理和正、逆运动学求解方法。从机械手的正、逆运动学方程的求解结果可以看出,采用液压方式实现对机械手6个自由度的驱动,具有驱动力大、操作简单、安装准确的特点,可适应多种汽车重载装配的需要。     

小波分析在弧焊机器人视觉检测中的应用

针对弧焊机器人薄板对接、搭接焊缝的自动焊接问题,将小波分析应用在CCD直接获取的焊缝图像的处理中,用来提取焊缝轨迹.根据薄板的对接和搭接焊缝图像的特点,建立了斜坡型及梯形小波分析模型,通过对模型的多尺度小波变换和李氏指数的分析,可以区分焊缝的边缘类型,从而增强了焊缝轨迹提取方法的抗干扰性和适应性,也为弧焊机器人的自动化和智能化焊接提供一定的技术参考.     

Teleoperated Puncture Robot System:Preliminary Design and Workspace Analysis

Radiofrequency ablation (RFA) guided by X-ray images aims to relieve herniated disc pain with mini-mal invasiveness and fast recovery.It requires an accurate and fast positioning of the puncture needle.We propose a teleoperated robotic system for percutaneous puncture to support RFA.We report the kinematics modelling and workspace analysis of the proposed system,which comprises preliminary and accurate positioning mechanisms.Preliminary positioning mechanism automatically drives the needle to the puncture area,and accurate positioning is then achieved by teleoperation under the guidance of X-ray images.We calculate the teleoperation workspace of the robot system using a spatial search algorithm and quantitatively analyze the optimal structural parameters aiming to maximize the workspace.The workspace of the proposed robot system complies with clinical require-ments to support RFA.     

基于DELTA机构的堆垛机器人

介绍了一种基于ＤＥＬＴＡ机器人机构的堆垛机器人设计,这种堆垛机器人和同等规格的串联机器人相比,具有高刚度,高精度和低机动质量等特点,适合于高速堆垛及搬运等操作。此设计还具有其他一些潜在应用,讨论了ＤＥＬＴＡ机构的奇异形位和运动学逆解等。     

Dynamic Obstacle Avoidance for Application of Human-Robot Cooperative Dispensing Medicines

For safety reasons,in the automated dispensing medicines process,robots and humans cooperate to accomplish the task of drug sorting and distribution.In this dynamic unstructured environment,such as a human-robot collaboration scenario,the safety of human,robot,and equipment in the environment is paramount.In this work,a practical and effective robot motion planning method is proposed for dynamic unstructured environments.To figure out the problems of blind zones of single depth sensor and dynamic obstacle avoidance,we first propose a method for establishing offline mapping and online fusion of multi-sensor depth images and 3D grids of the robot workspace,which is used to determine the occupation states of the 3D grids occluded by robots and obstacles and to conduct real-time estimation of the minimum distance between the robot and obstacles.Then,based on the reactive control method,the attractive and repulsive forces are calculated and transformed into robot joint velocities to avoid obstacles in real time.Finally,the robot's dynamic obstacle avoidance ability is evaluated on an experimental platform with a UR5 robot and two KinectV2 RGB-D sensors,and the effectiveness of the proposed method is verified.     

公路桥梁施工中伸缩缝的施工工艺和质量控制

桥梁工程中伸缩缝的施工质量对整个桥梁至关重要.结合桥梁工程伸缩缝施工工艺论述了其施工中的质量控制措施,并从多个角度论述伸缩缝安装中的质量控制要点.     

7R六杆Ⅱ级机构的MATLAB/SIMULINK动力学仿真

用矢量和矩阵理论建立了适用于MATLAB/SIMULINK仿真的曲柄、RRRII级杆组运动学和动力学数学模型,以该数学模型编制了M函数仿真模块,对给定的颚式破碎机7R六杆II级机构进行了建模和仿真,通过仿真得到各转动副的反力及驱动力矩.其主要目的是以构成机构的基本杆组为仿真模块,搭建杆组MATLAB/SIMU-LINK仿真模型,可以对不同类型平面连杆机构进行动力学仿真和分析.     

Y型圆钢管相贯节点轴向刚度计算模型

为获得Y型圆钢管相贯节点轴向刚度实用计算公式,基于环向模型和节点局部变形与轴向刚度的关系,建立了半圆拱模型,并导出了节点轴向刚度的理论公式;运用泰勒级数等数学手段,将理论公式中的复杂函数简化为能反映自变量间相互影响的指数函数与幂函数的乘积,并根据单参数分析结果忽略次要因素支主管壁厚比,获得了Y型节点刚度的简化计算式.研究结果表明:节点刚度与材料弹性模量、支主管平面内夹角正弦平方的倒数和主管直径成正比;支主管直径比和主管径厚比对节点刚度的影响较大;简化公式计算的刚度值与有限元计算结果和已有试验数据的相对误差基本小于8%.