Years ago, I read about an interesting touch sensor in a hobbyist magazine. However, I cannot find the article and I cannot remember the details well enough. So, I ask you all if you have heard of something like this:
The sensor was a ring that sat around the robot. It was constructed of a conductive material surrounded by a foam-like material. When the robot bumped into something, the system was able to determine that and approximately where the touch occurred on the ring. Perhaps by changing the resistance? It was an analog sensor, of course, but it allowed a fairly specific indication of where the touch occurred with a single sensor.
Any triggering of any memories? Any pointers would be appreciated.
thanks,
kenny