Ningbo Haitian Group Co., Ltd. (hereinafter referred to Haitian Group) is currently China's largest injection molding machine production base. Haitian Group, with an annual output of more than 3 sets of injection molding machines, many of which are internal components of the company processing, processing automation, high flexibility to become Haitian Industry 4.0 to achieve an important part.
The 11th branch of Haitian Group mainly completes the machining of the connecting rod. "With a wide range of plastic presses, there are more than 50 kinds of connecting rod specifications for the two machine tools in this project. It is very difficult to find a universal feeding mechanism, It is impossible. "The production engineer at Haitian Group pointed out:" It is a difficult task for robots to automatically load materials in order to achieve rapid tool changing. The company spent a lot of manpower, material and financial resources on this issue, but the result was twice as good.
In 2012, Cognex held a product launch in Suzhou. Haitian's production engineers attended the event and learned that Cognex is a leader in the global visual industry.
"It was just this project needs, naturally think of Cognex, they recommended to us has always been the cooperation of gold measuring company." Haitian Group's production engineers, said, "Golden test company specifically for the project a lot of Testing and research to finalize the use of Cognex powerful positioning algorithm PatMax visual tools to help us solve difficult problems.
"Because of the large number of connecting rods, Cognex directly brings the camera a lot of actual tests on different models of products and directly reflects the results and finds that the results are very good." The production engineer at Haitian Group pointed out that "we also They also used the concept of geometric pattern matching when they looked for other machine vision companies for testing and comparison, but the concepts were interpreted in different ways, so the final performance characteristics were very different and could not well adapt to Haitian's working conditions. "
Finally, Haitian chose the Cognex In-Sight 8405 series of smart cameras based on a combination of metrics such as camera throughput, accuracy, speed and pattern alignment, and the unique PatMax became the key to this automation project Cutlery.
The use of pattern matching technology is the key to determining the success of machine vision applications. When testing online, you need to search the template pattern in the camera's field of view for pattern matching. Pattern matching can sometimes be very difficult because there are many factors that affect how objects are displayed in the visual system.
Traditional pattern matching techniques are usually based on a normalized correlation pixel grid analysis process. This method looks for the statistical similarity between the grayscale level (or baseline image) of an object and various parts of an image, and then determines the X / Y position of the object. Although this method is very effective in some cases, the stability and accuracy of searching for objects may be limited when the external environment of the production line is often shaded, the angle, size and shape of the product are changed.
To overcome these limitations, Cognex introduced a proprietary algorithm based on geometric features called pattern matching, PatMax. PatMax is not affected by the grayscale change of the pattern. The geometry of the object is obtained according to the pixel grid boundary curve. PatMax then looks for a similar shape in the image, allowing the product feature to have angle and zooming freedom. This allows accurate positioning of product features regardless of object angle, size and shape.
PatMax®, the gold standard for positioning of workpieces and features in the industry, provides accurate and repeatable detection in the toughest conditions. PatMax technology was first patented in 1997 as the first high-accuracy, high-speed, high-throughput object-orientation technology in machine vision. PatMax SA, PatMax XLC, Synthetic PatMax, PatInspect®, PatFlex®, OCVMax ™ and The basis for assistive tools such as IDMax®, covering the broadest range of pattern matching and inspection in the industry.
Cognex In-Sight vision systems provide superior inspection, identification and guidance of workpieces. This industrial-grade, standalone vision system includes an advanced vision tool library with high-speed image capture and processing capabilities.
In the Haitian Group's production site, In-Sight vision system combined with robot automatic positioning and grasping to achieve automatic feeding, the perfect solution to the production problems, as follows: 1) 50 large and small connecting rod identification; 2) 2 different pallets Product recognition and automatic switching procedures; 3) The camera will automatically convert the image features into the robot corresponding to the coordinate point; 4) The camera will be sent to the coordinates of the robot, the robot for automatic positioning and grasping; Linkage automatic positioning identification grasping feeding, to achieve the machine's high flexibility, rapid change of needs.
In this project, the machine tool connecting rod automatic loading and unloading is divided into a total of 6 steps: 1) visual identification to guide the robots positioning crawling unstacking; 2) hydraulic tooling automatic clamping; 3) connecting rod hole processing automatically online Testing; 4) robot cutting laser coding; 5) robots unloading palletizing; 6) left and right processing of different parts of the two machines, robots automatically replace the jaws, Cognex intelligent vision system automatically switch templates for A model link up and down. In this way, the robot automatically identifies the layers according to the product features (aperture size) captured by the camera, and automatically locates and grabs layers by layer, greatly reducing the cost.
"We used PatMax to locate workpieces with advanced geometric pattern matching technology that is both reliable and accurate, and Cognex accurately and consistently finds workpieces even in the most extreme conditions, such as iron filings, greasy dirt and rust on workpieces , "Haitian Group's production engineer commented," This tool can also greatly reduce or eliminate the fixed requirements and costs, the original so many specifications of the product positioning mechanism can not be achieved, or need a lot of complex mechanical structure to achieve. Part or feature, PatMax is the largest and most reliable visual inspection tool in vision systems. "
"The whole system realizes the visual guiding robot to automatically pick up and load the material, the parts of the injection molding machine realize intelligent intelligence and manufacturing, which greatly reduces the labor intensity of the workers and increases the machine tool efficiency. Afterwards, all machining processes should be popularized and applied on a large scale." Haitian The Group's production manager finally stressed: "After many customers come to Haitian Group for further study, they have a deeper understanding of the strength of Haitian Group. We believe that with our injection molding machine + whole plant planning + information integration + peripheral aids integration + automation Integrated 'powerful tool, we can achieve a full range from the' only 'injection to the' smart 'injection of change.