Welcome to Synthiam!

Program robots using technologies created from industry experts. EZ-Builder is our free-to-use robot programming software that makes features like vision recognition, navigation and artificial intelligence easy.
Get Started

No, I did it in Synthiam EZ-Builder with an EZ-B V4/2.

It is in the MyRoli MKII project under my name.  I believe the script and object are named Edge Detector (I am at work and can't open the project from here).

This has come up a few times lately.  When I have a few minutes either tonight or maybe Wednesday I'll make a project without all the extra stuff just to demonstrate how this works.  Maybe even create a tutorial, although I never have enough free time for that lately.

I just posted a cliff detection sample project: https://synthiam.com/Community/Apps/cliff-detection-sample-18442

This uses an H-Bridge movement panel, and a Sharp IR sensor plugged into the ADC7 port.  The read-ADC control reads the value, and has a multiplier to adjust the sensitivity range.  The script waits for a change, and if the value is high enough that the robot would fall, it stops and backs up, then waits for further instructions.   You need to start the cliff detection script (in a real robot, you would probably call it from your init script) before driving the robot.

I believe I used a 5cm-30cm Sharp IR sensor, but I don't recall for sure.  You want one with a short enough range that it can detect drops when facing down from a mount point on the robot.

This could easily be adapted to use multiple sensors to detect cliffs on the sides and back and have different actions depending on which sensor triggered.

Thanks for the info and the link, I will try later,
I used my Arduino, com3 on EZ-builder

sharp sensor: 

used port ADC3

sharp IR radar

ADC graph

ADC  meter

ADC read

All went well