I believe that many users are very confused when they first come into contact with machine vision, and how to map their own project requirements to the numerous parameters of the visual system. Today, Weishi Xiaobian mainly explains how to convert project requirements from the perspective of the project. The requirements of the visual system parameters.
The general vision system includes industrial cameras, industrial lenses, visual light sources, image processing software, sensors, motion and control devices, and so on. Before there is a need for project inspection and selection, the structure of the project (including installation Environment, number of work stations, space for installable equipment), motion, accuracy of detection, speed of detection, language and tools for software development, use of third-party tools, etc. Focusing on the visual part, these requirements are combined with parameters.
The common selection order is Industrial Camera -> Industrial Lens -> Visual Light Source -> Peripheral Equipment...
Industrial Camera (Mainly for Area Array Cameras)
1, area camera / line camera
For stationary detection or general low-speed detection, priority is given to area-array cameras. For special applications such as large-format high-speed motion or roller axes, consider the use of line-array cameras;
2, resolution
The resolution actually refers to the number of camera pixel points, which is usually tens of thousands of pixels. However, when detecting, it is not necessary to pursue excessive pixels. The high pixel rate will result in a decrease in the frame rate and slow image processing. , The selection can be selected according to the project detection accuracy requirements. The accuracy of the project occupies 1 pixel in the image as the basic requirements, the software engineers with weaker levels can choose 3 pixels or more;
3, frame rate
Static detection is selected as much as possible, so that the entire project cost will be reduced a lot, but it will bring about a decrease in detection efficiency. For sports, if a frame exposure camera is used, the line exposure camera will cause picture distortion. For the specific frame rate selection, no Should be blindly selected high-speed cameras, although high-speed camera frame rate is high, but generally need to strengthen the light irradiation, the high cost and image processing speed is also a huge pressure, need to be based on the relative movement speed, as long as the detection area, can You can capture the object to be measured, for example, to observe the field of view with a length of 1 meter. The object to be measured passes through the field of view at a movement speed of 10 meters/second. It takes only 10-12 frames/second to fully capture the object to be measured. , but the same speed through the 0.1 meter field of view, you need to 100-120 frames / second camera.
4, color
In the industrial visual inspection, generally we recommend the use of black and white cameras, because software processing is generally converted to grayscale data processing, and industrial color cameras are converted by Bayer algorithm color, and there is a certain degree of true color gap;
5, chip type, size and pixel size
As far as the current status of the industry is concerned, for higher image quality or poor ambient illumination, it is recommended to use a CCD sensor and choose a larger pixel size camera. Of course, as the industry develops, the gap between CCD and CMOS is also Gradually decreasing, CMOS changes the resolution (ROI) more flexibly, the same resolution, the speed is higher.
In addition to the above parameters, before determining the camera, it is best to confirm whether the camera supports the development language or development tools required by the project and whether it is compatible with third-party tools such as Halcon, VisionPro, and Labview.
Today mainly introduces the selection of the camera according to the project requirements. In the next issue, we will continue to introduce lens and light source selection techniques. Interested partners can pay attention to us!
Passenger Elevator,Small Passenger Lift,Domestic Passenger Lifts,Hydraulic Passenger Elevator
XI'AN TYPICAL ELEVATOR CO., LTD , https://www.chinaxiantypical.com