Edge detection for mobile robot

I’m building up a software test-bed in the form of a small (11x12) mobile robot. I’d like to get some cliff/edge sensors on it (exactly like a roomba uses), to keep it from falling off various areas.
What sensor would you recommend? the base (underside of robot) is exactly 1" off the ground, so that would be the minimum distance required out of the sensor.

Any ideas?


  • Marti

Hello, Marti.

We have a few different sensors that you might be able to use in an application like that. Here is a link to our full proximity sensors and range finders category:

Specifically, our Sharp GP2Y0D805Z0F digital distance sensor detects objects between 0.5cm and 5cm (0.2″ and 2″) away, so that seems like it might fit your criteria.

Our QTR reflectance sensors might also work in an application like this:

Please keep in mind, with any of these sensors, how well they work can vary a lot depending on the exact details of your application, like how much ambient light there is in their operating environment. So, you might want to get a few different types of sensors to try out.

- Patrick

Thanks for the help. I ended up grabbing 4x of those digital small detectors, my logic is such that a 'dangerous" drop-off would definitely be over 2". Ideally I would get a sensor that could measure the distance and then do some real life testing to see what drop-off would be tolerable before tipping. But for now, I’ll take the possible tipping over versus it jumping off a stair ledge.