Yep, the antistatic foam that is in the EZ-Robot boxes will act as a resistor. As the foam is compressed it becomes less resistive and conducts more electricity. That is the theory anyway. I have to find something to do with all of these analog ports and this seems like as good of a thing as anything at this point. I can have 8 ports per hand right now. The thought is that 5 of these would be in the fingers and a few of them in the palm (thinking thumb, palm and pinky joints in the hand). This should allow me to know how tight something is being held. There is a ground run to the wrist just outside of the rotational servo.

Do the ground and signal pins have to run off of the EZ-B or is a common ground good enough? Lots of testing to do on this.

As for other points for contact sensing, I have 16 more analog ports to use. I figure shoulders, and head would be a good place to add some copper for touch sensing. I may do something in the stomach, not sure.

David, that would be awesome... Lots of finger stringing/wiring surgery coming you way soon... LOL

All the ground pins on every port on the ezb are common to each other. As long as you have at least one ground wire going back to the ezb you can make a common grounding point anywhere away from the ezb you would like for your analog ports. I like to run at least two grounds back to the ezb just in case one comes loose or breaks.

Thanks for the informtion Dave.

Well I conducted a test on this. The rubber that is used in the boxing is really good at suppressing voltage. I was however able to get it to act like a switch based on pressure. The foam kept the two contacts (signal and ground) separate until enough pressure was applied to make them "make contact".

It seems that the amount of this rubberized material makes a rather large difference as one would expect. I now have a lead glued to the outside of this material and another one very shallow in the material. I am now getting the pressure type sensor I am looking for. A little bit of paint over the top of the wire and it should be good. I will post pics when it is painted.

With the signal wire being on the outside of the material, it also acts as a touch sensor I guess. Non-conductive contact it acts as a pressure sensor, conductive material it acts as a touch sensor. Not bad...

This sounds pretty sweet. I knew that foam packaging would be useful for something else. Great idea David.

I have painted it with conductive paint. I will see how that works out and post.

If the conductive paint works out well, I will use this to paint the copper strip that I will use for the shoulder touch sensors. If it doesn't work out, I will have a lot of cleanup to do