Vision Sensor or Vision System - What’s the Difference and Which Vision Solution is for You?

Entry posted by Mark Guida August 11, 2020

1,685 views

For most of us in the industrial automation field, seeing a vision solution on a machine is commonplace. Some of us have specified them, some of us have programmed them, and some of us only know, “that’s the vision system over there.” With the latter being the most common, it becomes difficult for some to decide between the types of vision solutions. There are typically two types of self-contained (no separate controllers required) options: vision sensors and vision systems. There is a third type, PC based vision systems, that is an entirely different animal and you will know when you need it.

So why would you want a smart sensor in your application? Smart sensors give great ‘bang for the buck’. They carry a good set of features comparable to low end smart cameras at a fraction of the cost. Since these sensors do not require the computational horsepower or high-end feature sets of smart cameras, they can use smaller components with less heat dissipation requirements. This allows them to be packaged in much smaller housings that take up less space in a machine and reduces the overall weight of the sensor to reduce robotic payload burdens if mounted to end of arm tooling. If all you are looking for is to know the absence or presence of a feature pattern, edge, simple OCR/OCV, blobs, etc then a smart sensor is a great choice. A key differentiator from sensors to systems is that the sensors are generally much easier to program. Graphical programming environments with slider bars that immediately update the results of an inspection help set up a sensor very quickly.

If you need more horsepower because of inspection speed requirements, more internal logic capabilities, higher resolutions (2Mp and up), dimensional measurements, advanced OCR/OCV, 1D/2D code reading, defect detection, etc, then you will need to look to a vision system to solve your application. There are a lot of different models that will solve a given application with a price and feature set to match what you need. These vision systems can be programmed to solve just about any vision task thrown at them. The newest systems leverage machine A.I. and deep learning to solve applications previously only able to be completed by humans. These full vision systems are typically configured by an integrator or distribution partner who has been trained in setting up vision systems which adds to the cost of the entire system.

With all the differences, obvious or subtle, between the two types of solutions, there are a bunch of features to note that are common to both when talking about Cognex as a vision solution manufacturer. Programming software (except A.I. and deep learning versions) is the same for both the sensors and systems. Both are available with color imagers, autofocus lenses, integrated lighting/lens filter choices (white, colored, UV, and IR).

So, whether your application is simple or complex, high speed or slow, or on a tight budget, there is a solution for you. Knowing which is the right solution might just take a closer look.