Robotics in space-age manufacturing

Robotics technologies are developed to improve manufacturing of space hardware. The following applications of robotics are covered: (1) welding for the space shuttle and space station Freedom programs; (2) manipulation of high-pressure water for shuttle solid rocket booster refurbishment; (3) automating the application of insulation materials; (4) precision application of sealants; and (5) automation of inspection procedures. Commercial robots are used for these development programs, but they are teamed with advanced sensors, process controls, and computer simulation to form highly productive manufacturing systems. Many of the technologies are also being actively pursued in private sector manufacturing operations

Vision-aided Monitoring and Control of Thermal Spray, Spray Forming, and Welding Processes

Vision is one of the most powerful forms of non-contact sensing for monitoring and control of manufacturing processes. However, processes involving an arc plasma or flame such as welding or thermal spraying pose particularly challenging problems to conventional vision sensing and processing techniques. The arc or plasma is not typically limited to a single spectral region and thus cannot be easily filtered out optically. This paper presents an innovative vision sensing system that uses intense stroboscopic illumination to overpower the arc light and produce a video image that is free of arc light or glare and dedicated image processing and analysis schemes that can enhance the video images or extract features of interest and produce quantitative process measures which can be used for process monitoring and control. Results of two SBIR programs sponsored by NASA and DOE and focusing on the application of this innovative vision sensing and processing technology to thermal spraying and welding process monitoring and control are discussed

Welding Inspection System

This Project aims at building an automated welding system that can track a weld seam, calculate its area and depth and accordingly do the welding and also consider to keep the defects to a minimum so that better quality of weld can be given as output. It consists of a laser sensor that illuminates the weld seam so that the CCD/CMOS camera used can get the image of the weld seam. Then this image is transferred to MATLAB for image processing where the image is converted to grey scale and the grey scale image is then divided into two parts first part consists of the seam section which is colored grey and have red dots and other sections is considered as white section which don’t have any utilization till the welding starts. After the image processing the part is carried to the welding section where the welding can be done with the help of the data abstracted from the above methods and then it minimizes the defect of welding and produces the output

Welding Research for Shipbuilding: SP-7 Panel Program from 1972 to 1992

https://deepblue.lib.umich.edu/bitstream/2027.42/154147/1/39015075172463.pd

Robotic welding techniques in marine structures and production processes : a systematic literature review

Robotic welding has garnered significant attention in the maritime industry for its potential to enhance marine structure quality and optimize production processes. This systematic literature review aims to provide a comprehensive overview of the current state of research in robotic welding for marine applications, encompassing marine structures and production processes, following the PRISMA statement and guidelines. The review encompasses various facets, including welding techniques, processed materials, types of robotic welding, technological advancements, potential advantages, and challenges encountered when implementing robotic welding systems in the maritime sector. The results spotlight the pivotal role of gas metal arc welding (GMAW) in propelling robotic welding technology forward, while wire arc additive manufacturing (WAAM) has experienced a notable surge in popularity, signifying its potential to catalyze significant changes in maritime manufacturing processes. Notably, the predominant use of robotic welding centers on carbon steel materials. However, ongoing advancements indicate a growing diversification, with the incorporation of advanced materials like high-strength alloys on the horizon. Additionally, the utilization of 6-axis robot welding in conjunction with fully autonomous systems has emerged as a versatile and potent instrument that has revolutionized welding methodologies across various maritime research domains. Robotic welding provides a number of advantages, such as increased productivity, higher quality, adherence to industry standards, adaptation to confined and dangerous locations, and facilitation of innovative construction techniques. Nevertheless, adoption of this cutting-edge technology is not without challenges. By synthesizing the results from several investigations, this research study offers useful insights into the current knowledge gaps, emerging trends, and future prospects for the growth of robotic welding in maritime applications

Feasibility of remotely manipulated welding in space. A step in the development of novel joining technologies

In order to establish permanent human presence in space technologies of constructing and repairing space stations and other space structures must be developed. Most construction jobs are performed on earth and the fabricated modules will then be delivered to space by the Space Shuttle. Only limited final assembly jobs, which are primarily mechanical fastening, will be performed on site in space. Such fabrication plans, however, limit the designs of these structures, because each module must fit inside the transport vehicle and must withstand launching stresses which are considerably high. Large-scale utilization of space necessitates more extensive construction work on site. Furthermore, continuous operations of space stations and other structures require maintenance and repairs of structural components as well as of tools and equipment on these space structures. Metal joining technologies, and especially high-quality welding, in space need developing

Vision-guided tracking of complex tree-dimensional seams for robotic gas metal arc welding

Automation of welding systems is often restricted by the requirements of spatial information of the seams to be welded. When this cannot be obtained from the design of the welded parts and maintained using accurate xturing, the use of a seam teaching or tracking system becomes necessary. Optical seam teaching and tracking systems have many advantages compared to systems implemented with other sensor families. Direct vision promises to be a viable strategy for implementing optical seam tracking, which has been mainly done with laser vision. The current work investigated direct vision as a strategy for optical seam teaching and tracking. A robotic vision system has been implemented, consisting of an articulated robot, a hand mounted camera and a control computer. A description of the calibration methods and the seam and feature detection and three-dimensional scene reconstruction is given. The results showed that direct vision is a suitable strategy for seam detection and learning. A discussion of generalizing the method used as an architecture for simultanious system calibration and measurement estimation is provided

Real time defect detection in welds by ultrasonic means

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.A computer controlled weld quality assurance system has been developed to detect weld defects ultrasonically whilst welding is in progress. This system, including a flash analogue to digital converter and built-in memories to store sampled data, a peak characters extractor and a welding process controller, enabled welding processes to be controlled automatically and welding defects to be detected concurrently with welding. In this way, the weld quality could be satisfactorily assured if no defect was detected and the welding cost was minimised either through avoiding similar defects to occur or by stopping the welding process if repair was necessary. This work demonstrated that the high temperature field around the weld pool was the major source of difficulties and unreliabilities in defect detection during welding and, had to be taken into account in welding control by ultrasonic means. The high temperatures not only influence ultrasonic characteristic parameters which are the defect judgement and assessment criterion, but also introduce noise into signals. The signal averaging technique and statistical analysis based on B-scan data have proved their feasibility to increase 'signal to noise ratio' effectively and to judge or assess weld defects. The hardware and the software for the system is explained in this work. By using this system, real-time 'A-scan' signals on screen display, and, A-scan, B-scan or three dimensional results can be printed on paper, or stored on disks, and, as a result, weld quality could be fully computerized.Sino-British Friendship Scholarship Schem