Search results

The development of robotized welding is truly impressive and is today one of the major application areas for industrial robots. The first industrial robots were introduced in the early 1960s for material transfer and machine tending. Not long after that, robots were used for spot welding and in the early 1970s for arc welding as well. During the years, significant developments have taken place both concerning the robot equipment and the welding equipment to meet the different challenges within the application area. This paper describes the development and progress of robotization in welding over the years and also some projections and trends for the near future.

Automation of arc welding jobs is accelerating rapidly now that sensory feedback systems are beginning to become available. However, many of these systems have limited capabilities. A new laser‐based optical profile sensor developed in Holland not only tracks all types of seams but also modifies weld process parameters on the basis of profile information.

Progress in machine building is connected with computer integrated manufacturing (CIM) development. An essential part of CIM is a computer aided design (CAD) system for off‐line creation of manufacturing control programs. Each technological process is characterised by special equipment and operations, which complicate development of CAD off‐line programming systems. More than 90 robot programming systems and languages are now in existence. However, programming all technological aspects into one single CAD system is not possible so far; besides, a teaching method being required, the programs contain many operators, and the database of CAD/CAM is not sufficiently used.

Aims to present missing knowledge of welding and sensor application with rotating torch to the technically and economically meaningful employment. With the help of this knowledge, on the one hand, the potential user is to be informed about the applicability of the system in the context of his production line and his products and on the other hand, the classification of the system in the range of the alternatives available on market.

Introduces the welding operation and experimental results of rotating torch integrated with a sensor device using a 6‐axis robot. Performed various laboratory experiments investigating variable frequency values with different torch orientations.

Figures out the optimum frequency and torch orientation to obtain ultimate welding geometry by means of compensating gaps with increased weld root. Observed the possibility of out‐of‐position welding.

In this manner, provides a great scope as a pioneer application in industry and a guidance for forthcoming researches.

Allows welding of thin sheet metals.

Presents a seminal concept in the field of any industrial applications such as marine and pipeline construction.

Robotic wire and arc additive manufacturing (RWAAM) is becoming more and more popular for its capability of fabricating metallic parts with complicated structure. To unlock the potential of 6-DOF industrial robots and improve the power of additive manufacturing, this paper aims to present a method to fabricate curved overhanging thin-walled parts free from turn table and support structures.

Five groups of straight inclined thin-walled parts with different angles were fabricated with the torch aligned with the inclination angle using RWAAM, and the angle precision was verified by recording the growth of each layer in both horizontal and vertical directions; furthermore, the experimental phenomena was explained with the force model of the molten pool and the forming characteristics was investigated. Based on the results above, an algorithm for fabricating curved overhanging thin-walled part was presented and validated.

The force model and forming characteristics during the RWAAM process were investigated. Based on the result, the influence of the torch orientation on the weld pool flow was used to control the pool flow, then a practical algorithm for fabricating curved overhanging thin-walled part was proposed and validated.

Regarding the fabrication of curved overhanging thin-walled parts, given the influences of the torch angles on the deposited morphology, porosity formation rate and weld pool flow, the flexibility of 6-DOF industrial robot was fully used to realize instant adjustment of the torch angle. In this paper, the deposition point and torch orientation of each layer of a robotic fabrication path was determined by the contour equation of the curve surface. By adjusting the torch angle, the pool flow was controlled and better forming quality was acquired.

This paper presents the architecture of a system for robotic welding of complex tasks. The system integrates off‐line programming, control of redundant robots, collision‐free motion planning and sensor‐based control. An implementation for pipe structure welding made at Odense Steel Shipyard Ltd., Denmark, demonstrates the system can be used for automatic welding of complex products in one‐of‐a‐kind production.

Aims to present general concepts and framework for increasing the flexibility in robotic arc welding with respect to use of sensors and small series production.

Presents a conceptual model with a framework that integrates existing tools and needed developments and research to increase the usefulness of sensors in robotic arc welding. The conceptual model is based on research within the field which covers supporting tools like robot simulation, sensor modelling and handling and optimization issues with respect to the robot task execution. A descriptive structure and concept is outlined to include welding procedure specifications (WPS) as a key module to provide an integrated and holistic control model of the robotic.

Finds that the outlined conceptual model and architecture supports an increased flexibility of sensor controlled robots for arc welding applications. The arguments are specifically made for small series and one‐off production.

The paper is limited to arc welding applications and the concept and arguments are made with small series and one‐off production in mind.

Increased use of sensors and robots in small series production.

Introduces a holistic approach for task level control of a robot which introduces a structured way for integrated and coordinated control of the arc welding task. The objective is to execute the welding task with maintained robustness with respect to predefined specifications (quality, productivity).

This paper aims to present an optimal trajectory planning for industrial MOTOMAN MA1440A gas metal arc welding system. A new and efficient evolutionary algorithm, enhanced multi-objective teaching learning-based optimization (EMOTLBO) method, i.e. TLBO with non-dominated sorting approach has been proposed to obtain the optimal joint trajectory for the defined weld seam path.

The joint trajectory of the welding robot need to be computed in an optimal manner for proper torch orientation, smooth travel of the robot along the weld path and for achieving higher positional accuracy. This can be achieved by limiting the kinematic and dynamic variations of the robot joints like joint jerks, squared acceleration and torque induced in the joints while travel of the robot along the weld path. Also, the robot travel should be done within minimum possible time for maintaining productivity. This leads to a multi-objective optimization problem which needs to be solved for maintaining proper orientation of the robot end effector. EMOTLBO has been proposed to obtain the Pareto front consisting of optimal solutions. The fuzzy membership function has been used to obtain the optimal solution from the Pareto front with best trade-off between objectives.

The proposed method has been implanted in MATLAB R2017a for simulation results. The joint positions have been used to program the robot for performing welding operation along the weld seam. From the simulation and experimental results, it can be concluded that the proposed approach can be effectively used for optimal trajectory planning of MOTOMAN MA 1440 A arc welding robot system as a very smooth and uniform weld bead has been obtained with maximum weld quality.

In this paper, a novel approach for optimal trajectory planning welding arc robot has been performed. Though trajectory planning of industrial robots has been done before, it has not been done yet for welding robot. The objectives are formulated taking in consideration of requirement of welding process like minimization of joint jerks and torques induced during welding operation due to travel of robot with the effect of arc spatter, minimization of squared acceleration for maintaining constant joint velocity and finally minimization of total travel time for maintaining productivity.

Dutch specialists in enhanced visual observation make a successful move into an industrial manufacturing sphere.

The purpose of this paper is to present a CAD‐based human‐robot interface that allows non‐expert users to teach a robot in a manner similar to that used by human beings to teach each other.

Intuitive robot programming is achieved by using CAD drawings to generate robot programs off‐line. Sensory feedback allows minimization of the effects of uncertainty, providing information to adjust the robot paths during robot operation.

It was found that it is possible to generate a robot program from a common CAD drawing and run it without any major concerns about calibration or CAD model accuracy.

A limitation of the proposed system has to do with the fact that it was designed to be used for particular technological applications.

Since most manufacturing companies have CAD packages in their facilities today, CAD‐based robot programming may be a good option to program robots without the need for skilled robot programmers.

The paper proposes a new CAD‐based robot programming system. Robot programs are directly generated from a CAD drawing “running” on a commonly available 3D CAD package (Autodesk Inventor) and not from a commercial, computer aided robotics (CAR) software, making it a simple CAD integrated solution. This is a low‐cost and low‐setup time system where no advanced robot programming skills are required to operate it. In summary, robot programs are generated with a high‐level of abstraction from the robot language.