With the rapid development of modern science and technology, automatic detection equipment has high efficiency, saves labor, reduces production costs, and improves economic benefits. Therefore, many factories and enterprises now choose automation equipment. After they buy it back, because the operators have no experience, some small problems often affect the detection effect of the detection equipment in the production process. Today, the reputation of array technology for you to sort out some of the factors that affect the detection effect, I hope to help you!
1： Hardware selection
Stable image feature extraction is the premise of image analysis and image recognition. Only when a stable image is transmitted to the image processing center can the accuracy of image processing be ensured. Many factors will affect the stability of imaging, such as the surrounding environment, object changes, visual hardware and so on.
The selection of hardware for visual inspection is a difficult task, which requires engineers to be familiar with the hardware itself and hardware suppliers, and have enough selection experience. The environment of the machine vision system running in the laboratory is very different from that of the system running in the actual working scene.
Visual inspection includes some important parts, such as light source, lens, camera, image acquisition card, data transmission, image processing and measurement software. With the improvement of the performance of each component, the ability of machine vision system is also growing exponentially. The complexity of the system depends on the specific application requirements. To select the best component, we need to consider not only whether the performance of the component can meet the requirements (such as resolution, frame rate, measurement algorithm, etc.), but also the environmental conditions of the system. For example, in the industrial field, these environmental conditions include component change, transfer, positioning, processing interface, vibration, ambient light, temperature, dust, oil, water, electromagnetic radiation, etc. In extreme conditions, it is sometimes necessary to add protective measures to machine vision components. Most typically, some cameras need to be used in relatively clean environments. However, in general, the industrial environment is able to meet the direct use of industrial cameras.
Even the most stable vision system, often because of external influence, the result is not ideal, for example, vibration will lead to image blur distortion, and variable parts will lead to different images, too long exposure time will lead to image sharpness distortion of moving objects.
2： Environmental impact
The influence of environment on machine vision hardware is not only destructive to the hardware itself, but also affects the measurement effect. For example, in the environment of temperature change, most industrial cameras can work between - 5 degrees and 65 degrees. In the actual environment, too high temperature often brings noise to camera imaging. However, this can improve the signal-to-noise ratio by improving the lighting method.
In addition, the temperature will affect the performance of the LED light source. As the temperature of the LED rises, the brightness will decrease, which can be compensated by the light source controller. The heat generated by LED itself will also accelerate aging or even directly scrap, so a good thermal design is needed.
Other components also have corresponding temperature limits. For example, industrial controller / Embedded PC can generally use industrial environment, but if there is no fan, the PC is likely to be scrapped. In order to ensure the stability of visual imaging, in addition to choosing a good hardware, we should also consider the sensitivity of the object itself to temperature. For example, metal objects have thermal expansion and cold contraction for temperature, so when measuring such objects, the length and volume will change.
Most industrial cameras are vibration proof. Robots and track cables can make the camera move without vibration. The locked connector protects the camera from vibration. Durable PC and embedded computer have good stability protection mechanism. The fixed focus lens is protected from vibration by locking screws of metal interface. Filters protect the lens to a certain extent.
Daily filter can avoid the influence of ambient light to a certain extent, it can change the information of light into the sensor. By using a high brightness modulated light source, reducing the exposure time and aperture of the sensor, the influence of ambient light can be minimized. Using infrared and other wavelength camera to measure can reduce the influence of visible light.
·● dust, dirt, water
Many cameras can achieve IP65 / 67 protection level to ensure dust and water resistance. Dust, dirt, liquid and steam often adhere to the surface of LED or lens and affect the imaging. It can be adjusted by increasing the gain of camera, image processing of software and adjusting the output of LED.
A variety of environmental factors will affect the imaging, and these effects will be fatal, because the image is an important reference for measurement.
Shipping address: North China
Delivery time: March 02, 2021
Delivery product: cap detector