Vision Systems - Cognex & Keyence

Hello,

While searching for new controls engineering jobs/careers, I've noticed that many employers require experience working with vision systems.

Does anyone have any suggestions for where to start to become familiar with these types of systems and the programming that comes along with it. Maybe some sample PLC code or technical write ups/documentation.

Thanks!

If you are totally new to it all, I can recommend Stemmer's Imaging & Vision Handbook. https://www.stemmer-imaging.com/en/the-imaging-vision-handbook/?choose-site=active

Of course it has some Stemmer/Cognex bias, but there are a lot of basic knowledge in it, that is platform independent. With imaging and vision, proper lighting is always the big issue, and it does a good job explaining most of it, and gives you some input for seeking further knowledge.

Try and have a look at ebay or local auctions. From time to time you can pick up Cognex Cameras for a really nice price.

Most vision jobs are just a question of getting a stable read and have it transfered to the PLC. Most of the time you'll be using String formatted data so if you are not familiar with ASCII chars and string operations, you can read up on that for the PLC side of things.

Those employers must not get a lot of candidates if they are requiring vision experience, it's hard enough just to find controls guys around here!

Keyence and Cognex both have simulators with their software, so you don't need actual hardware if you don't want to. I'd start with reading up as much as you can, and then play around with some software.

Cognex has a great knowledgebase on their site with a ton of tutorials and technical papers. I want to say there's even some of their classroom documentation buried in there if you look hard enough. The Insight Explorer software is free and just requires some type of email registration to unlock it.

Keyence has a lot of great documentation on their site as well that even cover vision basics regardless of what manufacturer you're using. Their software is free also, but I remember there was something goofy about downloading (can't remember the details right now).

I have to agree with Mitch11, all the job openings in my area want people that know, vision, plc and robotics. All automotive related.

You can call your local keyence rep and he will gladly bring you some cameras to work with and demo. You can get a good idea of how the camera and software work, if there is a specific part you want to look at.

In my experience, one of the biggest challenges is getting communications between the PLC and the camera/sensor. Try to get familiar with setting up comms from PLC to other devices. If you already have some experience with this, for example setting up serial or Ethernet/IP comms to other instruments, that is a skill that will apply to vision systems as well as other systems you may be more familiar with.

I prefer Cognex myself. easier to work with in my opinion.

not to discourage you, but, things you MUST consider

demo parts are patterns are ideal, in the real world, their scratched, dirty, greasy. you will need the best production parts you can find, clean them up, program them as masters, and keep them in a padded container.

in your office / lab, lighting is ideal, in the real world, you must add / take away lighting, consider what kind of lighting you have.

in the lab, they give you the cameras and lenses, you MUST, MUST know how to determine what the smallest pixel size is in relation to measurement.
salesman will promise you the world for a sale only to sell you something that doesn't work and you buy more stuff to fix the issue.

plant work is a lot of trial and error at first, then you begin to learn the system and how to tune it in.

james

Cognex is definitely easy to get up and running with, they've got setup tools that make it easy. Depending on the product, Keyence can also be easy.

CommissioningMan said:

If you are totally new to it all, I can recommend Stemmer's Imaging & Vision Handbook. https://www.stemmer-imaging.com/en/the-imaging-vision-handbook/?choose-site=active

Click to expand...

I have had some experience with vision, this is a great resource. Learned a few new tricks. Thanks for sharing.

I've worked with both, both are easy to program. If price is your issue, then go with Cognex, they work just as good. But this depends on your application as well, if you are looking for holes drilled in a part for example, I have used ifm cameras, about $800 a pop, but only works with black and white color. Keyence will be super expensive, I would recommend finding brand new or semi-used ones on ebay for cheaper price. But all 3 are good, just depends on your application.