Kinematics analysis and experiment of a cockroach-like robot

This article describes the structure of the cockroach-like robot. Both kinematics and locomotion control are inspired by biological observations in cockroaches. Based on cockroach-like robot kinematics analysis, screw theory, and the production-of-exponential (POE) formula, this paper focuses on the inverse kinematics which uses Paden-Kahan sub-problems to obtain directly the displacement of joint angles. The forward kinematics derives the relationship between joint angles according to the natural restrictions. Then, by using the POE formula, it can deduce the body pose and realize online trajectory control and planning. Through simulation and experimentation, it is proved that the straight-line walking and turning gait algorithms have static stability and the inverse kinematics analysis of cockroach-like robot is correct.     

A real-time collision-free path planning of a rust removal robot using an improved neural network

In this paper, a real-time collision-free path planning of the rust removal robot in a ship environment is proposed, which is based on an improved biologically inspired neural network algorithm. This improved algorithm is based on the biologically inspired neural network and modified with obstacle detection sensors and kinematic state templates, and is implemented in a ship rust removal robot planning system for dynamic trajectory generation. The real-time optimal trajectory is generated by the biologically inspired neural network, and the moving obstacle detection process of a ship robot working on the wall is simulated with the obstacle detection sensors models. The local real-time trajectory can be re-planned by the updated local map information, where the obstacle detection sensors are used to inspect partial environment information and update the robot nearby information in real time in the original neural network algorithm. At the same time, the method of the kinematic state templates matching and searching is used to solve the pipes’ influence of the rust removal robot climbing on the wall, which can not only provide a smooth path, but also can judge the motion direction and turning angle of the robot. Comparison of the proposed approach with the simulation shows that the improved algorithm is capable of planning a real-time collision-free path with achieving the local environmental information and judging the rust removal robot’s motion direction and turning angle. This proposed algorithm can be good used in the ship rust removal robot.     

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.     

船舶工业机器人四丝焊不同相位关系的熔滴过渡

在本文的焊接规范下,对机器人四丝焊的不同相位的熔滴过渡进行了高速摄影分析.结果显示,前、后丝脉冲电流交替相位时,其电弧形态彼此间基本没有影响,呈现锥状;前、后丝脉冲电流同步相位时,其电弧彼此相互吸引,电弧向2个焊丝中间交汇集中;前、后丝脉冲电流随机相位时,其电弧时而同步,表现为彼此吸引,向2个焊丝中间集中,时而交替变化,电弧形态彼此间没有影响.     

Path Planning of Planar Kinked Line Seam by Visual Servoing for Robotic Welding

Welding path planning can substitute for the manual teaching process of the robot and can promote the autonomous level of the robotic welding. A path planning method by visual servoing was presented, in which the optimal angle of charge-coupled device (CCD) camera was also planned. Aiming at planning two forms of kinked line seams, obtuse angle seam and right angle seam, a practicable solution was put forward. In this solution, the intersection of two adjacent straight segments is detected in each local seam image, and if intersection is found, theseam errors are calculated using the next straight segment. The experimental results show that kinked line seam can be well planned using this solution.     

Path Planning of Planar Kinked Line Seam by Visual Servoing for Robotic Welding

Welding path planning can substitute for the manual teaching process of the robot and can promote the autonomous level of the robotic welding. A path planning method by visual servoing was presented, in which the optimal angle of charge-coupled device (CCD) camera was also planned. Aiming at planning two forms of kinked line seams, obtuse angle seam and right angle seam, a practicable solution was put forward. In this solution, the intersection of two adjacent straight segments is detected in each local seam image, and if intersection is found, the seam errors are calculated using the next straight segment. The experimental results show that kinked line seam can be well planned using this solution.     

孤立波浪边界干扰下流线型箱梁气动特性

近海流线型箱梁主梁距水面较低时,气动特性极易受到极端波浪边界的干扰.为研究极端波浪边界干扰下流线型箱梁气动特性,以孤立波浪模拟极端波浪,基于FLUENT软件,采用铺层网格技术建立了模拟运动孤立波浪边界干扰下流线型箱梁气动特性的数值模型;利用所建立并验证的数值模型研究了不同参数下运动孤立波浪边界对流线型箱梁气动特性（静气动力系数、涡量场以及平均压力系数和脉动压力系数分布）的干扰.分析结果表明：不同孤立波浪边界运动速度干扰下流线型箱梁气动特性明显区别于无波浪工况;随波浪边界运动,迎风角处剪切层方向相比于梁底转折角处（8°风攻角）及梁顶转折角处（-8°风攻角）剪切层方向变化明显;在运动孤立波浪边界干扰下,箱梁抖振响应会随风攻角幅值增大呈增大趋势.     

动态UP6工业机器人运动轨迹的实时规划

介绍了一种对运动中机器人的轨迹进行实时规划的方法。利用M otocom软件从机器人控制柜获取其当前的运动程序文件,通过一种轨迹规划算法,对运动中的机器人的轨迹进行实时规划,重组为运动程序文件,再通过M otocom32将文件上传给机器人控制柜,并使机器人按规划后的程序继续运行。这样便实现了对运动中机器人轨迹的实时规划。实验证明,这种轨迹规划的方法实时性较好,满足了一般工厂运行的要求。     

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.     

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 …     

Research on Miniature Hexapod Bio-robot

This paper described the structure and control of a new kind of miniature hexapod bio-robot, analyzed the moving principle of the robot. The robot is based on the principle of bionics, its structure is simple, design novel, unique. It can move forwards and backwards. The external dimensions of bio-robot is： length 30 mm, width 40 mm, height 20 mm, weight 6. 3 g. Some tests about the model robot were made. The experimental results show that the robot has good mobility.     

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 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.     

带附体圆柱的涡激振动特性研究

以带鳍状物附体二维圆柱为研究对象,采用动网格技术,通过FLUENT自定义函数接口进行流场与结构间的数据交换,对其涡激振动特性进行了数值研究.数值分析前,以裸圆柱为模型进行了计算并将结果与已有的实验数据进行了对比,验证了本文算法的有效性和准确性.数值计算中,分别对初始分支、超上端分支及下端分支条件下的带附体圆柱在不同来流攻角的涡激振动特性进行了研究.计算结果表明,对于初始分支与超上端分支,附体的存在能够减小圆柱的横向振动;下端分支在小来流攻角情况与初始分支类似,但在大来流攻角时附体的存在会增大圆柱的振动幅值.     

等离子体焊接枪的数值模拟

以等离子体钨极氩弧焊接枪为研究对象,通过求等离子体弧柱区域的能量方程、动量守恒、质量守恒及电流连续性方程,得到温度、速度、电流密度分布。数值模拟200A自由氩弧所得电弧等离子体温度分布与实验数据相当吻合。在此基础上研究了带有喷嘴的弧柱部分的数值模拟,以及温度、速度和电流密度的分布、电弧弧长和最高温度的关系。     

Analytical Solution for Model-Based Dynamic Power Factor Measurement in AC Resistance Spot Welding

On the basis of welding transformer circuit model, a new measuring method was proposed. This method measures the peak angle of the welding current, and then calculates the dynamic power factor in each half-wave. An artificial neural network is trained and used to generate simulation data for the analytical solution, i.e. a high-order binary polynomial, which can be easily adopted to calculate the power factor online. The tailored sensing and computing system ensures that the method possesses a real-time computational capacity and satisfying accuracy. A DSP-based resistance spot welding monitoring system was developed to perform ANN computation. The experimental results suggest that this measuring method is feasible.     

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.     

Multiple welding seam video transmission and monitoring of welding robot in local area network

A method of transmission and monitoring in local area network (LAN) for the welding seam video information of binocular vision welding robot is proposed. This paper uses MPEG-4 video CODEC functions of DivX, video for Windows (VFW) video capture technology, multi-threaded network communication idea and WinSock Socket in Visual C++ 6.0. In the end, client/server (C/S) communication model based on TCP/IP protocol has been developed. Experimental results show that the method can achieve the multiple welding seam video??s real-time transmission in LAN. Moreover, the Canny operator is used to realize the edge feature extraction of the seam image which is captured by the client, so that the edge of the seam extracted is continuous and clear.     

机器人焊割柱管相贯线的路径规划研究

近年来,柱管接管相贯线接缝焊割由传统的手工焊逐渐被焊割机器人操作所代替。本文建立了圆锥、球体与柱管相贯线的一般化数学模型,并将空间相贯线展成平面曲线,利用等步长原理获取焊割轨迹的路径点。为保证焊割精度,步长的数值由输入的允许插补误差值经计算获得。文中还给出了柱管相贯线获取焊割路径点的流程图。此方法方便了焊割程序的编制,提高了工作效率,同时又保证了焊割的平稳性和精确性。最后给出了一个常见的柱管相贯实例,利用Matlab软件编程得到了其相贯线焊割路径点。     

COLLISION-FREE OF MULTI-ROBOT SYSTEMS IN VIRTUAL ENVIRONMENT

IntroductionWith the development of automation and con-trol technology,on car- body plant,at present,consideration of multi- robot systems has become abasic requirement. With the help of multi- robotsystems,we can shorten production time,improveproduction quality and quantity,and decrease pro-duction error rate. Buthow multi- robots can coop-erate with each other,especially on welding pro-duction line for car- body,is what we concernabout the most.We hope to find a good way toplan out paths fo…