FLEXIBLE MAGNETIC WHEEL TYPE INTELLIGENT WELDING ROBOT FOR SPHERICAL TANK

An intelligent welding robot for spherical tank's all-position multi-layerwelds is developed. Based on the dynamics analyzing and simulation testing, a flexible magneticwheel mechanism is created as the robot's walking carriage. It makes the robot directly attracted tothe surface of the spherical tank so as to realize the all-position walking and welding withoutrail. At the same time, a CCD real-time tracing system is developed for the robot to repeatedlytrace the all-position and multi-layer seams. The welding tests show that the welding robot can makethe all-position and multi-layer welds with high tracing accuracy, excellent quality and reliablebehavior, and it can be applied for practical production.

Inverse kinematics and welding experiments of the intersecting pipe welding robot

A robot used for multi-pass welding of the piping branch junctions and nozzle attachments to main pressure vessels is 4-DOF serial mechanism, two mobile joints and two rotary joints are adopted in design. The kinematic model was established with DH parameters, the inverse kinematics was solved. According to the forward and inverse kinematics equations, the robot kinematics was simulated in Matlab, the simulations indicate that the solution for inverse kinematics can satisfy the welding requirements well. As there are size errors, processing errors and welding deformation, the path of welding is forecasted according to the previous welding situation, and then, the path is taught at desired via-points, which plays an important role in submerged-arc welding. The submerged-arc welding experiments indicate that the robot and the welding methods are preferable to ensure welding quality.

A high-precision control system for robotic welding positioner

Aiming at the robotic welding positioner with characteristic of parameter change, load change, nonlinearity, and an intelligent control system was researched and developed. This control system used a two-mode controller that based on Fuzzy and PID control method. The results of simulation show that the dynamic and steady performances of the intelligent controller are better than that of single PID or Fuzzy controller. This paper has made a detail theoretical analysis of the constitution design and real-time controlled software and brought up the design and fulfillment method of multi-task real-time control software of high precisely and numerically controlled welding positioner, which has a good result in practice.

Study on fuzzy control IGBT inverter arc welding power source for robot

Arc welding robot is playing more and more important roles in modern welding manufacturing, but now available welding power sources seldom satisfy with robot system requirements. In this paper, study on fuzzy control IGBT inverter arc welding power source for robot is developed to bring robotic advantages into full play. Firstly, fast response 500A IGBT inverter arc welding rectifier is developed. Secondly, fuzzy control system, which features multi-functions, fast response and wide using range, is developed and reliable measures for preventing interference are designed. Finally, technological experiments for carbon steel are made. The welding experimental results show that the goal of design is attained.

A360 Bot Framework: Empowering Smart Robotic Process Automation Solutions

This research paper explores the significance of the “A360 Bot Framework” in Automation 360 (A360) platform. A360 is Automation Anywhere’s cloud-based automation platform designed to make business processes more efficient. It’s known for its user-friendly interface, which allows both technical and non-technical users to use it effectively. Automation 360 is versatile, offering a range of tools to automate tasks, manage complex workflows, and integrate various applications. It empowers users to create customized solutions for their specific needs. Being cloud-based it ensures scalability, security, and real-time updates, making it a top choice in the fast-paced digital world. As demand for A360 rises, having a structured way to develop bots becomes crucial. The paper introduces the “A360 Bot Framework” as a guiding approach for bot developments. This framework ensures consistency and scalability, especially when working with both professional developers and non-technical users. It outlines key elements like setting up work folders, managing logs, dealing with errors, and ensuring secure bot execution. Ultimately, the “A360 Bot Framework” is presented as a foundational structure that enhances consistency, resiliency, and development efficiency. By following predefined practices and templates, bot developers can mitigate risks and streamline debugging processes. This framework accelerates the bot development lifecycle, allowing developers to focus on specific functionalities and value-added features. The research paper aims to provide insights into the benefits of adopting the A360 Bot Framework and its potential to revolutionize A360 bot development practices, leading to more efficient and effective automation solutions.

Seam-tracking based on dynamic trajectory planning for a mobile welding robot

A new seam-tracking method based on dynamic trajectory planning for a mobile welding robot is proposed in order to improve the response lag of the mobile robot and the high frequency oscillation in seam-tracking.By using a front-placed laser-based vision sensor to dynamically extract the location of the weld seam in front of torch,the trend and direction of the weld line is roughly obtained.The robot system autonomously and dynamically performs trajectory planning based on the isometric approximation model.Arc sensor technology is applied to detect the offset during welding process in real time.The dynamic compensation of the weld path is done in combination with the control of the mobile robot and the executive body installed on it.Simulated and experimental results demonstrate that the method effectively increases the stability of welding speed and smoothness of the weld track,and hence the weld formation in curves and corners is improved.

ALGORITHM AND IMPLEMENTATION OF AUTO-SEARCHING WELD LINE FOR WELDING MOBILE ROBOT

An algorithm of auto-searching weld line for welding mobile robot is presented. Auto-searching weld line is that the robot can automatically recognize a weld groove according to the characteristics of the weld groove before welding, and then adjust itself posture to the desired status preparing for welding, namely, it is a process that the robot autonomously aligns itself to the center of welding seam. Firstly, the configuration of welding mobile robot with the function of auto-searching weld line is introduced, then the algorithm and implementation of auto-searching weld line are presented on the basis of kinematics model of the robot, at last trajectory planning among auto-searching weld line is investigated in detail. The experiment result shows that the developed welding mobile robot can successfully implement the task of auto-searching weld line before welding, tracking error precision can be controlled to approximate ±1.5 mm, and satisfy the requirement of practical welding project.

Study on motion simulation of arc welding robot based on UG

The motion simulation of arc welding robot is the basis of the system of robot off-line programming, and it has been one of the important research directions. The UGNX 4. 0 is adopted to establish 3D simulating model of MOTOMAN-HP6 arc welding robot. The kinematic model under link-pole coordinate system is established by the second development function offered by UG/OPEN API and the method of programming using VC ＋＋ 6. 0. The methods of founding model and operational procedures are introduced, which provides a good basis for off-line programming technique under Unigraphies condition.

Seam tracking control for mobile welding robot based on vision sensor

To solve the seam tracking problem of mobile welding robot,a new controller based on the dynamics of mobile welding robot was designed using the method of backstepping kinematics into dynamics.A self-turning fuzzy controller and a fuzzy-Gaussian neural network(FGNN) controller were designed to complete coordinately controlling of cross-slider and wheels.The fuzzy-neural control algorithm was described by applying the Gaussian function and back propagation(BP) learning rule was used to tune the membership function in real time by applying the FGNN controller.To make the tracking more quickly and smoothly,the neural network controller based on dynamic model was designed,which utilized self-learning and self-adaptive ability of the neural network to deal with the partial uncertainty and the disturbances of the parameters of the robot dynamic model and real-time compensate the dynamics coupling.The results show that the selected control input torques make the system globally and asymptotically stable based on the Lyapunov function selected out;the accuracy of the proposed controller tracing is within ±0.4 mm and can satisfy the requirements of practical welding project.

An approach to measure the pose of RHJD4-1 arc welding robot for calibration

A measurement setup used for robot calibration was designed to meet the requirement of off line programming technique. The robot end effector pose (position and orientation) can be calculated indirectly by using this setup. The setup has been applied to RHJD4 1 arc welding robot. The experimental results show the method of pose measuring using the measurement setup is simple and reliable to finish pose measuring for robot calibration. In addition, the setup can measure the position repeatability of robot.

Study on intelligent welding mobile robot with the function of auto-searching weld line

The development of welding robots suitable for specially unstructured working enviroments has been become an important development direction of industrial robot application because large-scale welding structures have been used more and more widely in modern industry. In this paper, an intelligent mobile robot for welding of ship deck with the function of autosearching weld line was presented. A wheeled motion mechanism and a cross adjustment slider are used for the welding robot body. A sensing system based on laser-PSD （position sensitive detector） displacement sensor was developed to obtain two dimensional deviation signals during seam tracking. A full-digital control system based on DSP and CPLD has also been realized to implement complex and high-performance control algorithms. Furthermore, the system has still the function of auto-searching weld line according to the characteristics information of weld groove and adjusting posture itself to the desired status preparing for welding. The experiment of auto-searching welding line shows that the robot has high tracing accuracy, and can satisfy the requirement of practical welding project.

Mathematical modeling and simulation application for a wheeled mobile robot applied on pipe welding

A geometric model was built to represent the position relation of a wheeled mobile robot relative to a pipe. The relationship between the deviation of falling off for the robot and the curvature of the pipe was formulated quantitatively. Based on the relationship, a mathematical model was derived and a fuzzy control algorithm for the robot was developed. Simulations were carried out to confirm the dynamic index and the validity of the mathematical model of the fuzzy control algorithm for seam tracking of pipe welding. Experiments for pipe welding with the mobile robot were also carried out to verify the algorithm, and the results showed that the seam has a good quality with a preferable appearance of weld.

Kinematic Study on Motoman HP6 Arc Welding Robot Based on Unigraphics

The links of Motoman HP6 arc welding robot are considered as an open kinematic chain which consists of a series of rotational joints through concatenation. One end of the open chain is fixed to the base or the earth, and the other end which is free fastens the end executor to complete various duties. Each link of this arc welding robot has four kinds of Denavit-Hartenberg parameters: common normal length between two adjacent links, angle of two adjacent joints, distance between the crossing of common normal length and two joints axes, and angle of two adjacent links. The displacement relation between each link of the Motoman HP6 arc welding robot is introduced, and the kinematic positive-going solution and the kinematic passive-going solution are calculated.

Readiness of a Developing Nation in Implementing Automation and Robotics Technologies in Construction： A Case Study of Malaysia

The Malaysian government＇s vision to be a developed nation by 2020 has pushed forward the use of innovative technologies in most sectors and industries, including the construction industry. Through the ETP （Economic Transformation Programme）, major projects launched are expected to provide a great catalyst for the economy, and may become the platform for increasing the use of automation and highly enhanced plants and machineries in the construction industry. Innovations in most countries are mostly driven by the need to find revolutionary solutions to problems, such as a shortage of skilled labor, decreasing quality of product and processes, inferior working conditions, declining productivity and increasing costs of labor and materials. Automation and robotics technologies encompass a wide range of innovative technologies using technologically advanced machineries to improve the speed and efficiency of a given process. This paper discusses the readiness of a developing country in embracing construction automation and robotics, by exploring industry perception, suggested practices and barriers to its implementation using a questionnaire survey and semi-structured interviews directed at Malaysian construction finns of contractors, specialist sub-contractors, developers and consultants. The findings show that the Malaysian construction industry is ready, to a certain extent, for implementing the technologies in limited areas such as prefabrication and assembly and in the design, planning and costing phases.

The Review of the Welding Robot’s Precision

Welding is an significant link in industrial production,and it is known as the"industrial tailor".However,welding fume,arc light,and metal spatter cause a harsh welding working environment,and the quality of welding has a decisive influence on product quality.Low production capacity,difficult recruitment,and low profits have become drawbacks for the development of the welding field.Combining traditional welding with robots can solve these drawbacks and increase the precision of welding.Welding robots are industrial robots engaged in welding and are mostly used in large-scale manufacturing fields such as automobile manufacturing.Welding robots are divided into spot welding robots,arc welding robots and laser welding robots.In addition,body accuracy and control accuracy are the two main factors that affect the robot welding accuracy.In this case,the sensing technology of welding robot is also essential.

Automation Technology in Welding Seam Welding Machining Design

With the continuous development of society,the gradual improvement of mechanical automation technology has been introduced into the production of many enterprises in China,which has had a great impact on the increase of China′s gross national product.Applying mechanical automation technology greatly saves labor cost,improves working efficiency and the production level of enterprises,effectively promotes the development of enterprises,and increases the enterprise′s income.In addition,mechanical automation technology is closely related to product production⁃related technology and plays a very important role in the innovation of enterprise products.This article will briefly introduce the design and application of automation technology in welding seam welding design,and understand the development background,research status,current application and simulation design.

Pose Planning for the End-effector of Robot in the Welding of Intersecting Pipes

All-position robots are widely applied in the welding of complicated parts.Welding of intersecting pipes is one of the most typical tasks.The welding seam is a complicated saddle-like space curve,which puts a great challenge to the pose planning of end-effector.The special robots designed specifically for this kind of tasks are rare in China and lack sufficient theoretical research.In this paper,a systematic research on the pose planning for the end-effectors of robot in the welding of intersecting pipes is conducted. First,the intersecting curve of pipes is mathematically analyzed.The mathematical model of the most general intersecting curve of pipes is derived,and several special forms of this model in degraded situations are also discussed.A new pose planning approach of bisecting angle in main normal plane（BAMNP） for the welding-gun is proposed by using differential geometry and the comparison with the traditional bisecting angle in axial rotation plane（BAARP） method is also analytically conducted.The optimal pose of the welding-gun is to make the orientation posed at the center of the small space formed by the two cylinders and the intersecting curve to help the welding-pool run smoothly.The BAMNP method can make sure the pose vertical to the curve and center between the two cylinders at the same time,therefore its performance in welding-technique is superior to the BAARP method.By using the traditional BAARP method,the robot structure can become simpler and easier to be controlled,because one degree of freedom（DOF） of the robot can be reduced.For the special case of perpendicular intersecting,an index is constructed to evaluate the quality of welding technique in the process of welding.The effect of different combination of pipe size on this index is also discussed.On the basis of practical consideration,selection principle for BAARP and BAMNP is described.The simulations of those two methods for a serial joint-type robot are made in MATLAB,and the simulation results are consistent to the analysis.The mathematical model and the proposed new pose-planning method will lay a solid foundation for future researches on the control and design of all-position welding robots.

Constant Speed Control for Complex Cross-section Welding Using Robot Based on Angle Self-Test

Expandable profile liner（EPL） is a promising new oil well casing cementing technique, and welding is a major EPLs connection technology. Connection of EPL is still in the stage of manual welding so far, automatic welding technology is a hotspot of EPL which is one of the key technologies to be solved. A robot for automatic welding of＂8＂ type EPL is studied. Four quadrants of mathematical equations of the 8-shaped cross-section track of EPL, consisting of multiple arcs, are established. Mechanism program for complex cross-section welding of EPL based on angle detection is proposed according to characteristics of small size, small valleys, and large forming errors, etc. A welding velocity vector control model is established by linkage control of a welding vehicle, a small driven actuator, and a height tracking mechanism. A constant speed control model based on an angle and symmetrical analysis model of rectangular coordinate system for EPL is built. Constraint conditions of constant speed control between each section are analyzed with 4 sections in first quadrant as an example, and cooperation work mechanism of the welding vehicle and the small tracking actuator is established based on pressure detection. The constant speed control model using angle self-test can be used to avoid the need for a precise mathematical model for tracking control and to adapt manufacture and installation deviation of EPL workpiece. The model is able to solve constant speed and trajectory tracking problems of EPL cross-section welding. EPL seams welded by the studied robot are good in appearance, and non-destructive testing（NDT） shows the seams are good in quality with no welding defects. Bulge tests show that the maximum pressure of welded EPL is 35 MPa, which can fulfill expansion performance requirements.

Seam Tracking and Visual Control for Robotic Arc Welding Based on Structured Light Stereovision

A real-time arc welding robot visual control system based on a local network with a multi-level hierarchy is developed in this paper. It consists of an intelligence and human-machine interface level, a motion planning level, a motion control level and a servo control level. The last three levels form a local real-time open robot controller, which realizes motion planning and motion control of a robot. A camera calibration method based on the relative movement of the end-effector connected to a robot is proposed and a method for tracking weld seam based on the structured light stereovision is provided. Combining the parameters of the cameras and laser plane, three groups of position values in Cartesian space are obtained for each feature point in a stripe projected on the weld seam. The accurate three-dimensional position of the edge points in the weld seam can be calculated from the obtained parameters with an information fusion algorithm. By calculating the weld seam parameter from position and image data, the movement parameters of the robot used for tracking can be determined. A swing welding experiment of type V groove weld is successfully conducted, the results of which show that the system has high resolution seam tracking in real-time, and works stably and efficiently.

Control algorithm based on trajectory and orientation of oblique intersection line welding-cutting robot

Working principle for a four-axis oblique intersection line welding robot is analyzed. A mathematical model for welding torch orientation angle is established, and an interpolation algorithm based on time division is proposed. The algorithm makes all interpolation points fall on a required curve in theory with no accumulated errors and a direct interpolation control on the saddle-shaped curve trajectory and space orientation angle can be achieved. It is shown by MATLAB simulation that the algorithm is real-time and fully meets the precision requirement. The algorithm has been applied to real robots.