As imaging technology continues to improve, so does its impact on manufacturing. Machine vision systems are nothing new, of course, but they now allow for a much wider range of uses within production facilities. From increasing production speed by automating previously manual processes, right through to improving the accuracy of quality control, vision systems are more commonplace than ever.
However, there isn’t just one single vision system that fits all uses. And despite its continual growth, many companies are only just beginning to recognise its benefits. Because of that, there can still be some confusion over which system is best suited to a particular application.
Walking into the word of automation can feel intimidating, given the breadth of new technology and opportunities it affords. To help you gain a brief overview of the different types of machine vision systems available and what their best uses may be, we’ve gone through each one below:
Rather than looking at the picture as a whole, 1D vision will analyse one batch at a time, comparing the most recent with an earlier completed set. A line-scan camera for a product that moves along on a conveyor belt would be ideal for this system. If it is a product that is being produced in a continuous process then it can pick up defects on materials such as plastics, paper and metal. A line-scan camera allows more light to be concentrated onto a smaller surface area, creating an image that is easier to read. Using the correct parameters, a 1D sensor even provides the opportunity to stitch together the line images to create a 2D image, if required.
Line scan systems are more effective when used to inspect products or round parts, as a number of cameras may be needed to cover the surface of the item. When the product is rotated for a single line camera to scan, by unwrapping the image it can capture the entire surface. These cameras are able to scan through much tighter spaces at times when conveyor rollers or other parts may be interfering with a wider view. The resolution produced by a line scan system is also far better than a traditional camera. They are also more suited for items and products that are in motion, as the creation of the image depends on the product itself moving.
A 2D sensor, or camera, can be used in an opposite sense, for products that are motionless and not moving along a conveyor. Depending on what you are using it for, there are a couple of options available, depending on the type of 2D camera you buy; one captures the image before passing it onto a computer to be analysed, others feature both the sensor and the processor itself in one.
Some example process that 2D sensor image processing can be used for include; finding edges, matching pattern/shape, blob analysis, looking for specific shape/colour on non-conforming shapes/colours.
As with 2D sensors, 3D is also more commonly used today with automated inspection, quality control, robot guidance, sorting and more. This vision system usually consists of a number of cameras or multiple laser displacement sensors. 3D scanners employ a number of different techniques such as structuring the lighting and laser triangulation. Because of the multiple cameras in use, 3D sensors will produce even more data that will need to be processed and stored somewhere, so take this into consideration before purchase. They are also quite specific in terms of the applications they can be used with, so it’s important to make sure the correct scanning system is purchased to suit requirements.
If you are close to purchasing a machine vision system, we hope this has given you some insight into the direction you should take. While the information is brief, it will at the very least allow you to relate your current process to a system that is designed to produce optimal returns.
As experts in automation and the installation of machine vision systems, we are always available to answer any further questions you may have. We understand that your needs are unique and approach each new enquiry with the individual attention it deserves. To find out more detail on how machine vision systems can benefit your current set-up, email our helpline firstname.lastname@example.org, or call us on 01223 499488.
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