Looks interesting. I'm going to have a go at giving my own robot a sense of touch at some point, and I've been wondering what type of sensors I should use.

The sensors will be built into the fingers, palm and thumb of my robot humanoid. I could make some kind of small switch, but I'd like to make something which gives an analogue 0-5V signal so that the robot can tell how much pressure is being applied to each sensor.

Anybody have any ideas?

Resistive flex sensors might work, Jameco has some. Simple voltage divider for an analog voltage, here. Another possibility might be strain gauges though I haven't found a low cost source of those, or more specifics on their use.

has anyone ever toyed with a sensor similar to a touch lamp? i had an electronics kit when i was a kid, you know the boards with the componenets and springs? i had constructed a circuit from it one time called a touch switch. when i touched the end of a loose wire or the spring it was connected to, an LED would light up. i can't seem to find this cicuit online. but i would imagine you could solder this wire to a piece of sheetmetal and insulate it from the robot. so you could make the robot have sheetmetal skin but in sections. when a human touches it it will know what section a human has touched. i think only humans could trigger the sensor but not sure. anyone know anything about this touch switch?

I agree with the above poster.. Those resistor "bend" sensors you sometimes see integrated into gloves sounds like a good, reliable and inexpensive place to start.

I would run them through the A/D converter and give that a shot.

There's also a fiber optic "laser whisker" sensor outlined in the 'Robot Builders Bonanza' book that works pretty well. It exploits a flaw in stepped index fiber optic cables (you lose some throughput as they bend) He then measures this up with a photo transistor and A/D to effect a light touch sensor.

Maybe something like that?