How can robots get a share of the polishing market?

CCTV's National Defense Military Channel "National Defense Science and Industry" once reported the story of Li Shifeng, a sheet metal worker at Xi'an Aircraft Corporation, who knocked out hundreds of fighter planes with a hammer. Moreover, not only do we do this, but this method is also common internationally. In the Boeing factory in Seattle, there are more than 20 people like Li Shifeng who are responsible for polishing the aircraft skin. Various large civil aircraft such as Boeing 737, 757, 767, and 777 are all hammered out in the Seattle factory. In the Airbus factory in Toulouse and the Rolls-Royce factory in Derby, there are also workers holding hammers and chisels who are responsible for polishing the aircraft skin. Why is the polishing of some parts still mainly done manually when today's industrial technology is highly automated? With such questions, let's discuss the difficulties of the polishing process, the current situation and prospects of polishing automation, how to become an old "grinder" through polishing? How can robots get a share of the polishing market?

1What is polishing?

Grinding is a type of surface modification technology, a processing method that changes the physical properties of a material surface through friction, with the main purpose of obtaining a specific surface roughness. In traditional manufacturing, grinding is widely used. For example, parts after casting, forging, and welding usually need to be polished to improve contour accuracy and surface quality; precision lenses, large and complex components such as blades, thin-walled parts made of special materials, etc. require grinding to meet special surface requirements. As in the above industrial scenarios, complex materials, complex and changeable processing techniques, and other reasons bring about a variety of specific requirements for grinding, resulting in the need for humans to rely on experience and independently judge how to better grind.

2. The current situation, prospects and difficulties of polishing automation

As the aging of the society becomes more and more serious, there is a lack of young grinders, a large shortage of skilled workers and insufficient labor. At the same time, with the vigorous development of automation and robotics technology, automated grinding has gradually developed and is widely used in automobile manufacturing, 3C industry, home appliance parts industry, wood building materials and home furnishing manufacturing industries, etc. It is used for surface grinding of workpieces, deburring of edges and corners, grinding of welds, deburring of inner cavities and holes, etc.

Compared with manual polishing, robot polishing can avoid the impact of sparks, dust and noise on human physical and mental health; it can solve the problem of inconsistent polishing; it can reduce labor costs and improve production efficiency. Data shows that in 2022, the market size of polishing and grinding robots in my country will reach 9.61 billion yuan, a year-on-year increase of 18.7%, among which the automotive and 3C industries ranked first and second, accounting for 18.9% and 19.5% respectively. In the future, as the demand for automation in the manufacturing industry continues to be released, robot polishing, a "potential stock", is expected to expand its use.

Undoubtedly, the advantages of robot grinding are very obvious, but due to the particularity and difficulty of the grinding process, after years of development, the application scale of polishing robots is still relatively small.

As for the reasons for the slow development, through observation of the market, there are roughly the following constraints: 1. It is difficult to completely transfer the grinding experience of experienced grinders to the robot program; 2. It is difficult to achieve random adjustment of force control to cope with the complex changes in the surface of the workpiece being processed; 3. The grinding paths in some scenarios are complex, and it is difficult for the robot trajectory to adapt; 4. Grinding scenarios can be roughly divided into soft and hard materials, soft materials such as plastics, wood, etc., and hard materials such as metals, etc. Hard materials have high requirements on robot rigidity; 5. The scene versatility is low, and the types of polished workpieces are diverse, making it difficult to replicate similar processes on a large scale.

3How do robots grow into old "grinders"?

The road ahead is long and difficult, but the future is promising. Robot polishing is an inevitable trend, but how to become an old "grinder"? This is not something that can be achieved overnight. Although the process of automated polishing is not as fast as other processes, it is worth celebrating that, as far as the editor knows, many collaborative robot companies have been working hard in the polishing market for more than ten years, hoping to spark the sparks of empowering traditional processes, and in some industries, a spark is turning into a prairie fire. This article only takes the collaborative robot company, JEKA Robot, as an example. Facing technical difficulties such as contact force control and trajectory planning of polishing robots, after years of case practice and technical accumulation, it has formed a mature flexible intelligent force control polishing solution. And it has been well applied in industries such as automobiles and 3C.

In order to solve the problem of complex and changeable curved surface shapes and difficult automatic grinding trajectory planning, the JIEKA robot has created a multi-point teaching + self-developed force control. The JIEKA robot can carry grinding tools and operate according to the customized teaching trajectory, and under the action of force control compensation, it can adjust the force in real time according to the changes in the product surface contour, meeting the trajectory tracking and adaptation requirements of planes, edges, and even large curvature and complex surfaces.

In order to solve the problem of product consistency, Jieka Robot has launched the six-dimensional force + constant force compliance function. The sensor accuracy can reach 0.5% of the measuring range. Jieka Robot can provide real-time feedback, adjust and accurately ensure constant force grinding, so that the grinding tool fits the product surface closely within the set contact force range, effectively solving the problem of uneven grinding and over-grinding of workpieces, and improving product consistency.

In view of the wide variety of products and diversified polishing needs, JAKA robots can enable enterprises to achieve rapid production change. JAKA collaborative robots have a force range of up to 800N, a torque range of up to 40Nm, and an overload capacity of up to 5500N/160Nm. They are compact and flexible, and can be deployed and debugged quickly.

In terms of use, the JAKA grinding robot is suitable for operators and can be quickly put on the job. After a short period of training, workers can quickly master the JAKA graphical & drag teaching function. The JAKA Zu APP has built-in existing programming modules. Workers can quickly set straight lines, arcs, and multi-level nested grinding paths by combining instruction modules. Programming is as simple as building blocks. The force control drag teaching of the JEKA robot is very smooth. Workers can manually drag the robot to edit point-to-point trajectories. It is simple and intuitive, and the debugging is flexible.

At present, Jieka robots have relatively mature applications in industries such as automobiles, 3C electronics, and furniture wood.

In the automotive industry, the grinding and polishing of the mold line of the rearview mirror cover has been achieved. In view of the special shape and material of the rearview mirror cover, JAKA has created a flexible and adaptive solution for the grinding and polishing of the rearview mirror cover.

In the 3C electronics industry, metal shell grinding and cutting have been realized. The JIEKA robot, through integrated composite fixtures and floating grinding tools, cooperates with tooling fixtures, so that the robot can replace manual labor to complete the grinding and polishing process and automatically cut materials, thereby improving product consistency and yield rate, reducing manual labor intensity, and improving the work experience.

In the general industry, furniture wood curved surface grinding is realized. In addition, JEKA robots also have outstanding performance in the grinding scenes of hardware, ceramic products, medical equipment and other fields.

Relying on core technologies and scenario practice experience in trajectory planning and smoothing, terminal jitter suppression, etc., JIEKA Robotics continues to solve the problems of polishing automation in thousands of industries, helping manufacturing production lines to unleash the "polishing" power of automation.

I believe that as more and more companies continue to devote themselves to the industry, study the market, and improve their technology, high-quality automation polishing will eventually be achieved in more fields.

Reviewing Editor: Huang Fei