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The purpose of this study is to develop a robotic training system for the hand movements during manual welding. The system provides real-time notice-feedback with sound or light alarms, whenever the welding hand vibrates beyond the nominal level observed with professional welders.

The large variations of hand movements are detected by monitoring the deviation of the tool position from a smooth curve estimated in real time by a Kalman filter. An alarm is generated in the form of a flashing light or beep sound whenever the deviations exceed a predetermined threshold. The performance of hand movements is measured in terms of the variations of the position data. Twelve novice and five professional welders took part in the experiments and answered a questionnaire that assessed the usability and work load of the system.

Compared to the sound alarms, the light alarms resulted in a larger and statistically significant decrease in the variation of hand movements of the novice welders and brought the level of variation close to that of the professional welders. The alarms did not result in a significant decrease in the variation of hand movements of the professional welders. The responses to the questionnaire indicated that both professional and novice welders found the system useful and they did not experience any significant work load.

The system developed in this study can ease the training of novice welders, by speeding up the learning and reducing the need for human tutors.

This study is first to provide real-time notice-feedback for training while manual welding, based on a comparison of the performances of novice and professional welders.

Welding is becoming increasingly unacceptable as a manual job and this is causing an acceleration in the trend towards automation. This paper briefly reviews some recent efforts at automating welding processes, including a program in the UK by the National Engineering Laboratory and the Welding Institute, and considers the future progress and effects of automation in this field.

The membrane wall is one of the most important components in the boiler industry and numerous studs are welded on its surface. The membrane wall welding still remains a sector intensive in the manual and arduous works. This paper aims to propose a dual-robot system to automatically weld studs on the membrane wall.

In this paper, the authors proposed a dual-robot stud welding system for membrane walls. First, the membrane wall is divided into several zones and the welding paths are planned. Then, the pose of the pipes is calculated based on the data measured by light section sensors. The planned paths are compensated by the pose. Finally, the robots weld studs based on the compensated paths.

The method effectively eliminates manufacturing errors and welding distortions. The system can weld straight type and L-type membrane walls with high efficiency, high quality and high accuracy.

The system can weld straight type and L-type membrane walls with high efficiency and high quality. Experiments were performed in a factory to demonstrate the practicability of the method. The dual-robot system with two welding machines has approximately twice the efficiency of the manual welder with only one welding machine. The quality and accuracy of robot welding systems are higher than that of manual welding.

Automating the welding process for the shipbuilding industry is very challenging and important, as this industry relies heavily on quality welds. Conventional robotic welding systems are seldom used because the welding tasks in shipyards are characterised by non‐standardised workpieces which are large but small in batch sizes. Furthermore, geometries and locations of the workpieces are uncertain. To tackle the problem, a Ship Welding Robot System (SWERS) has been developed for the welding process. The main features of the SWERS include a special teaching procedure that allows the human user to teach the robot welding paths at a much easier and faster pace. In addition, operation of the system is made easier through a custom designed man‐machine interface. Through this interface, only a few buttons need to be pressed to command the robot into different modes. Optimised welding parameters can be selected from a large database through a Graphical User Interface system.

In common with many engaged in engineering manufacture, the welding fabricator is under continuing pressure to increase productivity in order to remain competitive in home and international markets.

In this report, accounts will be presented on the experience obtained from approximately 100 practical applications of industrial robots. The industrial robots used derive partly from the company's own production as well as from other domestic and foreign robot manufacturers.

Development and demonstration of an autonomous, mobile welding robot capable of fabricating large‐scale customised structures.

An autonomous welding robot has been developed under the EC Framework V Growth program. The system comprises a global vision system for part location and orientation, and a robot transport vehicle (RTV) which carries a 6‐axis robot, robot controller, welding equipment, and local sensors at the welding torch. The RTV path, robot arm motion and weld process programming are performed automatically using sensors and specially customised simulation software.

The technology developed within the project was demonstrated, in November 2004, to be capable of identifying and welding large scale customised structures as found in the earth moving equipment and bridge fabrication industries.

The project demonstrated that current sensor technology is capable of being applied successfully to autonomous robots, but further developments in sensor technology are required to improve accuracy and joint access.

The NOMAD concept of autonomous mobile robots provides an alternative solution to welding mass customised structures.

This project demonstrated, for the first time, the capability of autonomous robots to weld large scale customised structures.

A lecture held in Paris the 22 April 1966 during an ESAB symposium on the subject of the development of methods for electrical welding, and originally published in Esab Svetsaren, no. 1, 1968 (Box 8850, S‐402 71 Göteborg 8, Sweden.)

FEW materials have made such an impact on the engineering scene as have titanium and its alloys. Whilst titanium was first isolated in 1825 it was not at that time recognised as having very desirable properties and no convenient method of extraction was found until 1940. Since then no efforts have been spared in developing the metal and its alloys, rapid progress having been made as reflected by the fact that titanium is now available in wide variety. Its high strength to weight ratio, especially when alloyed, offers considerable attractions to the aircraft industry, and in this field manufacturers have not been slow in taking advantage of the increased pay loads to be gained by using titanium and its alloys in place of more dense materials. Probably the largest single factor in enabling full exploitation is the case with which titanium can be joined by a number of processes and techniques, a brief review of which is given in the present paper. The costs of using the various processes arc not considered in this review, but nonetheless, it is noteworthy that economic aspects as well as technical requirements continue to stimulate further development.

The purpose of this paper is to establish a maturity evaluation model for the application of construction steel structure welding robotics suitable for the actual situation and specific characteristics of engineering projects in China and then to assess the maturity level of the technology in the application of domestic engineering projects more scientifically.

The research follows a qualitative and quantitative analysis method. In the first stage, the structure of the maturity model is constructed and the evaluation index system is designed by using the ideas of the capability maturity model and WSR methodology for reference. In the second stage, the design of the evaluation process and the selection of evaluation methods (analytic hierarchy process method, multi-level gray comprehensive evaluation method). In the third stage, the data are collected and organized (preparation of questionnaires, distribution of questionnaires, questionnaire collection). In the fourth stage, the established maturity evaluation model is used to analyze the data.

The evaluation model established by using multi-level gray theory can effectively transform various complex indicators into an intuitive maturity level or score status. The conclusion shows that the application maturity of building steel structure welding robot technology in this project is at the development level as a whole. The maturity levels of “WuLi – ShiLi – RenLi” are respectively: development level, development level, between starting level and development level. Comparison of maturity evaluation values of five important factors (from high to low): environmental factors, technical factors, management factors, benefit factors, personnel and group factors.

In this paper, based on the existing research related to construction steel structure welding robot technology, a quantitative and holistic evaluation of the application of construction steel structure welding robot technology in domestic engineering projects is conducted for the first time from a project perspective by designing a maturity evaluation index system and establishing a maturity evaluation model. This research will help the project team to evaluate the application level (maturity) of the welding robot in the actual project, identify the shortcomings and defects of the application of this technology, then improve the weak links pertinently, and finally realize the gradual improvement of the overall application level of welding robot technology for building steel structure.