A machine vision system consists of technology and methods based on creating a digital image of the environment, in order to perform automatic control, control the process or guide the robot. It includes software, hardware, integrated systems and methods.
As a term, it is mainly used in industrial automation but also in other environments, such as security systems and vehicle control.
The process of the machine vision system involves three steps:
2) Automatic analysis
3) Providing the required information
The machine vision system replaces labour-intensive manual inspection with fast, automatic digital image processing. Thanks to rapid developments, systems have become significantly cheaper and offer a good return on investment.
There are two types of machine vision systems, 2D and 3D.
The scope of the machine vision system covers a wide range of tasks, from presence verification to real-time inspection and sorting.
Basic tasks of the machine vision system:
· Inspection – checking the quality of the product, detecting defects and anomalies
· Measuring – identifying the dimensions of objects (length, width, height, area, volume)
· Reading – decoding and reading texts (barcodes, 2D codes, letter recognition)
· Positioning – detecting and locating an object.
The image to be analysed is obtained from the camera image or barcode scanner. Most of the time, the image is high contrast and black and white. In such images, lighting is a key factor. 2D vision is suitable for places where objects have high contrast or where it is essential to determine their colour. The 2D system enables tasks to be performed in all four categories.
3D vision is ideal for determining the volume, shape and spatial location of an object. In addition, 3D can detect low-contrast objects and defects when their heights vary.
3D imaging can be performed using both scanning and snapshot imaging.
· When scanning, the object moves through the scanner's field of view at a constant speed and creates a 3D profile from the object
· Imaging creates a 3D model of the object from the image.
Scanned images are generally significantly more accurate than regular images.