Although the machine vision system always looks very complex and specialized, if the existing automation system is systematically planned and reformed, the product quality can be improved and the production cost can be reduced.

A successful example is Compex in New Jersey, USA, which manufactures single-layer components used in high-frequency wireless RF, microwave, telecommunications, and fiber optic products. The company's factory area is 16,000 square feet, and its annual output is more than 10 million. However, if we use artificial means to inspect products, we will waste too much labor. Therefore, they chose a set of machine vision systems from Cognex Corp. They hope to change.

The system consists of a Cognex In-Sight 1000 vision sensor, a robot, a feed conveyor, a pneumatics conveyor, and a PLC. In the design of this vision system, the main challenge is the configuration problem of the illumination light source and the optical system, and how to make all the component products get a full test without changing any settings.

Image Acquisition

The sensor of the machine vision system is first to verify whether the orientation of the component is correct, and then to detect the size of the component and analyze it by capturing the image of each component transmitted by the vibration feed conveyor. If the orientation of the component is correct, the PLC will receive the relevant signal and then instruct the robot to place the component in the specified position. The detection time of the entire system is approximately 300 milliseconds. If the orientation of the component is not correct, the Pneumatic Component Conveyor will retract the component to the infeed conveyor. This requires that the positioning and measurement tools be configured in the software of the machine vision system. Equipped with a built-in calibration procedure, this program can re-adjust the camera's lens magnification within five seconds in the event of a camera misalignment.

Component count

The counting system is a stand-alone desktop operating system that does not require any PLC and only requires a high-resolution vision sensor with 1600 x 1200 pixel resolution. The detection system involves counting the thousands of small components in a short period of time. It can search and count the minimum number of parts that you want to produce.

To ensure that there are no mistakes, it is crucial to choose the right software "tools" for the vision system. First, designers use a design tool called "morphology" to help the machine vision system search for the needed ones among the large number of components that are transmitted. Then use the "blob" tool to determine the position of this part and use it as an internal count. Although these are advanced graphical calculation methods, the user simply selects, imports, and imports the system definition of the component from the screen menu.

The specific operation process is that the operator uses a visualized operation interface to select the type of components to be counted, then opens the system and observes the working status of the packaging process on the monitor screen in real time so that the packaging process can be properly adjusted within the field of view of the camera. After completing this task, the operator opened the system's counting function. The system continuously verifies that the packaged parts are correct and counts continuously. The images are stored on the computer's hard drive. Statistical data is stored in a SQL database and then analyzed to provide a complete component shipment report.

Brian LeBlanc, Compex's engineering manager, commented: "This system solves our bottleneck in the delivery operation and reduces the labor cost in operation by 80%."

Source: Modern Packaging