Machine vision
Machine vision is the application of computer vision to factory automation. Just as human inspectors working on assembly lines visually inspect parts to judge the quality of workmanship, so machine vision systems use digital cameras and image processing software to perform similar inspections. A machine vision system is a computer that makes decisions based on the analysis of digital images.
Machine vision systems are programmed to perform narrowly defined tasks such as counting objects on a conveyor, reading serial numbers, and searching for surface defects. Though machine vision systems have neither the intelligence nor the learning capability of human inspectors, they are considered useful in many applications. Manufacturers favor machine vision systems for pixels
- Thresholding: converts an image with gray tones to simply black and white
- Connectivity & segmentation: used to locate and/or count parts by differentiating between light and dark connected regions of pixels
- Barcode reading: decoding of 1D and 2D codes designed to be read or scanned by machines
- Optical character recognition: automated reading of text such as serial numbers
- Gauging: measurement of object dimensions in inches or millimeters
- Edge detection: finding object edges
- Template matching: finding, matching, and/or counting specific patterns
- Robust pattern recognition: location of an object that may be rotated, patially hidden by another object, or varying in size
In most cases, a machine vision system will use a combination of these processing techniques to perform a complete inspection. A system that reads a barcode may also check a surface for scratches and measure the length and width of a machined component.
Applications of machine vision
Machine vision systems are widely used in semiconductor device fabrication; indeed, without machine vision, yields for computer chips would be significantly reduced. Machine vision systems inspect silicon wafers, processor chips, and subcomponents such as resistors and capacitors.
In the automotive industry, machine vision systems are used to guide industrial robots, gauge the fit of stamped metal components, and inspect the surface of the painted vehicle for defects.
Though machine vision techniques were developed for the visible spectrum, the same processing techniques may be applied to images captured using imagers sensitive to other forms of light such as infrared.
Related fields
Machine vision is distinct from computer vision, an academic field of research often classified as a subfield of artificial intelligence. Computer vision extends to topics related to autonomous robotics and machine representation of human vision. Machine vision refers to automated imaging systems used in factories, assembly plants, and other industrial environments.
See also
