According to the statistics, nearly half of the industrial robots in the world are used in various forms of welding and processing fields. There are mainly two kinds of welding robot applications, namely spot welding and arc welding. Some of these welding robots are specially designed for a certain welding method, while most of them are actually composed of general industrial robots equipped with a certain welding tool.
The application of industrial robots in the welding field started from the resistance spot welding on the automobile assembly line. The reason is that the process of resistance spot welding is relatively simple, easy to control, and does not require weld track tracking, and the control requirements for robot accuracy and repetitive accuracy are relatively low.
Now let's review the four key technologies of welding robots in the automotive field.
1. Weld tracking technology
In the application process of robots, the application of weld tracking technology is relatively common. In the summary of welding operation process, because the welding process may be affected by strong arc radiation, smoke, splash, processing error, fixture accuracy, work piece thermal deformation and other factors, special attention should be paid to the control of these factors to avoid the deviation of welding torch from the weld, resulting in welding quality problems, and the existence of weld tracking technology, To a certain extent, it can monitor the deviation of the weld in real time in combination with the change of the welding conditions, and adjust the welding path and welding parameters in time to effectively avoid the quality problems in the welding process.
2. Offline programming and path planning technology
In the process of welding operation, offline programming and path planning technology mainly refers to the further expansion of robot programming language. It mainly uses the model of the robot's working environment established by the research results of computer graphics, and carries out certain control and operation on the graphics of welding devices through professional algorithms, so as to promote the robot to carry out welding operations on the basis of the set path planning, Another practical basis of offline programming is the application of automatic programming technology. Through the application of automatic programming technology, in order to realize the welding task, welding parameters, welding path and welding track, it is a technology to assist the programmer to carry out the programming task.
3. Multi-robot coordinated control technology
In the actual work process, the multi-robot coordination control technology mainly refers to the integrated system composed of several robots selected to complete a certain work task through cooperation and coordination. In the application process, the multi-robot coordination control technology mainly refers to how to organize the equipment to carry out effective work according to the actual operation task before the multi-system arranges a certain task. After determining the working mechanism, it is necessary to consider how to maintain the consistency of robot motion coordination in combination with actual work.
4. Special arc welding power source
Continuous practical work experience shows that in the system, the special arc welding power supply with good electrical performance is one of the keys to ensure the normal performance of the equipment. Most of the special arc welding inverters used by robots are transistorized arc welding inverters controlled by a single chip microcomputer. The welding power supply with precise waveform control method can ensure the consistency of the welding width and depth to a certain extent, and promote the welding surface to be more beautiful. Therefore, in the application process, it is very important to carry out in-depth research on the special arc welding power source.