Kalman Filtering for Seam Tracking in Master-Slave Robot Remote Welding System

Welding seam tracking precision is a key factor influencing welding quality for master-slave robot remote welding system. However, it does not satisfy the welding requirement due to significant noises. To eliminate the influence of noises upon the seam tracking precision and improve the seam tracking precision, a master-slave robot remote welding system was built and Kalman filtering (KF) was applied to the seam tracking process. The experimental results show that the KF eliminated the influence of noises upon the seam tracking precision and improved the seam tracking precision.

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Experimental Evaluation of the Preview Servo Scheme for a Two-Axis Positioning System

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.3149657 ◽

1984 ◽

Vol 106 (1) ◽

pp. 1-5 ◽

Cited By ~ 18

Author(s):

M. Tomizuka ◽

D. Dornfeld ◽

X.-Q. Bian ◽

H.-G. Cai

Keyword(s):

Kalman Filter ◽

Kalman Filtering ◽

Experimental Evaluation ◽

Experimental Results ◽

Positioning System ◽

Velocity Control ◽

Filtering Theory ◽

On Line ◽

Sharp Corners ◽

Welding System

A preview servo scheme for position and velocity control is implemented on a two-axis welding table. The Kalman filtering theory is used to estimate the velocity from position measurements, and a cornering scheme is proposed to attain smaller path errors at sharp corners. The experimental results show that the preview-servo scheme with the Kalman filter and corner preview features is suitable for on-line control of the welding system.

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The Friction Interaction Mechanism of Welding Seam Identifying Based on Force Sensing

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.291-294.995 ◽

2011 ◽

Vol 291-294 ◽

pp. 995-998

Author(s):

Lijun Liu ◽

Xian Yi Li ◽

Hong Ming Gao

Keyword(s):

Interaction Mechanism ◽

Experimental Results ◽

Force Sensing ◽

Vision Sensor ◽

Average Deviation ◽

Welding Seam ◽

Feed Direction ◽

Remote Welding ◽

Friction Interaction

The welding seam identifying(WSI) is one of remote welding precondition. The welding seam is usually identified by vision sensor. The investigation on WSI based on force sensing is less reported. Because the interaction mechanism of friction is not clear in 6 dimension(6D) force of WSI, the influence of friction on the WSI feed and direction is studied. The experimental results show that the friction will decrease the WSI feed in XSY plane and increase in Z direction, but they is in range permitted by WSI. The friction makes WSI feed direction point to the middle of welding seam track, and do not influence WSI. Above technologies, The WSI of S groove is achieved. The average deviation of WSI is less than ±0.5mm when there is friction in 6D force of WSI. It can meet the precision of WSI in remote welding.

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Design of Control System for Welding Tractor Based on DSP

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.155-156.1020 ◽

2012 ◽

Vol 155-156 ◽

pp. 1020-1024

Author(s):

Zhong Hu Yuan ◽

Yong Qiang Wu ◽

Jia Han Wang

Keyword(s):

Control System ◽

System Design ◽

Software Design ◽

Closed Loop ◽

Seam Tracking ◽

Experimental Results ◽

Closed Loop System ◽

Welding Seam ◽

Brushless Motors ◽

Hardware Circuit

In order to realize the curve welding seam tracking of welding tractor, the welding tractor driven by two rear wheels is researched in this paper. The control system that a DSP controls two DC brushless motors is designed. It contains the whole system design, hardware circuit and software design. It is designed as a double closed loop system. Experimental results verified the feasibility of the whole system.

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Advanced Automatic Welding System for Offshore Pipeline System with Seam Tracking Function

Applied Sciences ◽

10.3390/app10010324 ◽

2020 ◽

Vol 10 (1) ◽

pp. 324 ◽

Cited By ~ 1

Author(s):

Jin-Hyeong Park ◽

Hyeong-Soon Moon

Keyword(s):

Tracking System ◽

Seam Tracking ◽

Step Motor ◽

Pipeline System ◽

Automatic Welding ◽

Welding Seam ◽

Control Module ◽

Motor Module ◽

Welding Productivity ◽

Welding System

Automatic welding technology is a solution to increase welding productivity and improve welding quality in offshore pipe welding. To increase welding productivity, it is necessary to save time during the assembly/disassembly of the guide track from the welding carriage and pipe to move the next station. The guide track consists of a pneumatic system that does not separate the welding carriage, and two welding carriages operate on a half-pipe joint to increase productivity. These welding carriages automatically operate under the controller command. An automatic welding system consists of a DC motor module, a step motor module, a welding control module, a welding monitoring module, and a central control module. The control systems incorporate control modules and transmit commands to each module for an automatic welding system. In order to minimize the inevitable misalignment between the centerline of the welding seam and the welding torch for each welding pass, a moving average algorithm for seam tracking is proposed, which was proven to be suitable for the root pass, filling pass, and cap pass. Welding experiments were also carried out to verify the validity of the weld seam tracking system.

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Multi-Seam Tracking With a Portable Robotic Welding System in Unstructured Environments

10.21203/rs.3.rs-1186666/v1 ◽

2022 ◽

Author(s):

Shuangfei Yu ◽

Yisheng Guan ◽

Zhi Yang ◽

Chutian Liu ◽

Jiacheng Hu ◽

...

Keyword(s):

Forward Direction ◽

Seam Tracking ◽

Robotic Welding ◽

Production Environment ◽

Welding Torch ◽

Tracking Process ◽

Starting Point ◽

Low Efficiency ◽

Working Parameters ◽

Welding System

Abstract Most welding manufacturing of the heavy industry, such as shipbuilding and construction, is carried out in an unstructured workspace. The term Unstructured indicates the production environment is irregular, changeable and without model. In this case, the changeable workpiece position, workpiece shape, environmental background, and environmental illumination should be carefully considered. Because of such complicated characteristics, the welding is currently being relied on the manual operation, resulting in high cost, low efficiency and quality. This work proposes a portable robotic welding system and a novel seam tracking method. Compared to existing methods, it can cope with more complex general spatial curve weld. Firstly, the tracking pose of the robot is modeled by a proposed dual-sequence tracking strategy. On this basis, the working parameters can be adjusted to avoid robot-workpiece collision around the workpiece corners during the tracking process. By associating the forward direction of the welding torch with the viewpoint direction of the camera, it solves the problem that the weld feature points are prone to be lost in the tracking process by conventional methods. Point cloud registration is adopted to globally locate the multi-segment welds in the workpiece, since the system deployment location is not fixed. Various experiments on single or multiple welds under different environmental conditions show that even if the robot is deployed in different positions, it can reach the starting point of the weld smoothly and accurately track along the welds.

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Robot Based Laser Welding Technology

Materials Science Forum ◽

10.4028/www.scientific.net/msf.580-582.565 ◽

2008 ◽

Vol 580-582 ◽

pp. 565-568 ◽

Cited By ~ 1

Author(s):

Hee Shin Kang ◽

Jeong Suh ◽

Taik Dong Cho

Keyword(s):

Laser Welding ◽

Tracking System ◽

Welding Process ◽

Seam Tracking ◽

Welding Quality ◽

Monitoring Method ◽

Welding Technology ◽

Non Linear ◽

Tailored Blank ◽

Welding System

In order to obtain a good result in the laser welding process, the laser welding technology for manufacturing an automobile body is studied in this research. The monitoring of the welding quality and the seam tracking are studied to improve the productivity. The robot, the seam tracking system and CW Nd:YAG laser are used for the robot laser welding system. The laser system is 4kW Nd:YAG laser_(HL4006D) of Trumpf and the robot system is IRB6400R of ABB. The robot laser welding system is equipped with the seam tracker and plasma sensor. The seam tracking system is composed of SMART-20LS and RAPAL of Servo-Robot and MVS-5 sensor of MVS. The precise positioning of the laser beam on the joint to be assembled is obtained by seam tracker. The welding joints of steel plate are butt and lap joint. The three dimensional welding for non-linear tailored blank is performed after the fundamental experiments of bead-on-plate. Finally, the welding process for non-linear tailored blank and front side member is studied. The monitoring method of welding quality and seam tracking along the butt-joint are studied. The artificial defects in joint are well observed by the plasma intensity signal from the plasma sensor of UV and IR. The robot based laser welding system is developed for the precision seam tracking and the real-time monitoring of welding quality.

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