The application of robotic flexible laser cutting in the automotive industry is becoming increasingly common, which is inextricably linked with the development of laser technology and the perfection of robot precision trajectory control technology. Because robotic flexible laser cutting can provide highly flexible solutions, and the cost is much lower than that of imported five-axis machine tools, auto manufacturers are now beginning to try and gradually buy them in batches.

There are many ways of robotic flexible laser cutting, which can be made into a single-robot cutting platform or combined into a flexible processing production line. The workpieces involved are mainly two different types of parts: one is the 3D car body structure and cover formed by extrusion or drawing of metal parts, including thermoformed parts; the other is the tubular metal structure, Including exhaust pipes, cross beams, etc. The traditional production method of covering parts is to punch through the die, and then carry out the punching die and trimming die and other processes; the thermoformed parts and pipe fittings are completed by expensive five-axis laser cutting machine tools. Because of the high equipment costs, only certain automakers with joint venture brands have the ability to purchase imported five-axis machine tools.

Under the new situation, the needs of car users are becoming diversified and individualized, and more and more new models are emerging. Most cars are gradually shrinking in batches. Because some car manufacturers cannot predict and guarantee the sales and stable output of a certain model in the future, they have begun to try low-cost robotic laser flexible cutting equipment or production lines. This trend started from the automotive spare parts market, and continued to expand and popularize in the fields of construction machinery, passenger cars, agricultural vehicles, and electric vehicles.

Laser cutting robots for the automotive industry

Many industrial robots are used in the automotive industry, but there are few applications in the field of laser cutting. The problems exist on three levels. First, the application of robots in the automotive industry is mainly focused on spot welding, arc welding, spraying, handling, etc., with low precision requirements, but laser cutting often requires high position accuracy, and high requirements for small trajectories such as small circles, such as The cutting of small circular holes with a diameter of less than 5mm is beyond the reach of ordinary robots. A small circle of 10mm will also appear in shapes such as ellipses; on the other hand, depending on the efficiency of the robot, the joint motion control speed of each axis of the general robot is relatively slow, and the robot The arm weight is too large and is not suitable for high-speed motion; the third aspect is the rigidity of the robot. The robot with poor rigidity will shake badly, the robot will have poor tracking, and the robot deforms so badly that it cannot accurately reach the precise position that needs to be cut in the digital model of the workpiece. Therefore, it is understandable that the robots popular in the traditional automobile industry have been questioned by customers in laser cutting.

Stäubli, which has a century of experience in precision machinery and high-speed motion control, has the widest design field in the automotive industry. In response to the needs of the automotive industry, Stäubli has implemented the RX160L flip-chip gantry structure robot flexible cutting system solution in the laser aspect. The system has made breakthroughs in the following aspects:

• 1. Large size robot wide format. Using the RX160L robot, the 2.05m spherical working area, the cutting table width can reach 3m, which exceeds the width of the worktable of an expensive five-axis machine tool. Generally, the size of auto parts is within the working area of ​​the RX160L flip-chip robot, and some large workpieces can also be used. Realize through the mobile platform.
• 2. The arm is light in weight and has good rigidity. Stäubli uses an integral cast tubular structure to maintain rigidity; the material is made of aerospace cast aluminum with less deformation but light weight. The weight of the RX160L robot arm is only 250kg, while the European robot with the same arm is more than 400kg, which is very unsuitable for the needs of robot flexible laser cutting.
• 3. The mechanical accuracy difference of the robot. In addition to the rigidity difference of the robot mechanical accuracy, the most important difference lies in the error of the mechanical transmission, and the error of the mechanical transmission is mainly reflected in the reducer. The deceleration system of general robots is very large, and they all adopt the structure of ordinary reducer, and the gear gap is large, which cannot meet the needs of robot flexible laser cutting in the automotive industry. The unique patented deceleration system JCS adopted by Stäubli, the company has successfully applied more than 100 years of experience in precision machinery to robots. This is why Stäubli Bier can be recognized by customers for small hole cutting.