touch sensing questions

Hello,

Basically I want to hook up a few alligator clips to something like a plant and get some numbers back in my serial port...and then if I were to touch that plant I would get different numbers based on where and how I touch it. Then I could get a 0-1023 output and send that number off to another program. So for example - while the clips are hooked up I get some numbers in the 0-100 range...I touch the plant on one side, I get some other numbers from 300-600, I touch somewhere closer to the sensors, I get 800-100...etc.

So I see the arduino touche tutorial on instructibles...but I just want one number back and I'm really not sure how to get that out from that tutorial...it seems like only this weird graph thing is possible and I don't understand the code at all.

There is the capacitive touch sensor on SparkFun but that just seems to give you a yes or no if something is touched and not a varied number based on how you touch that thing...

so i was just wondering if anyone has any advice/guidance as to which direction to go or any info on touch sensing. are there any other methods I'm missing? is there an easy way to get a int variable so i could just do Serial.println(plantInfo); and get a 0-1023 number with either of the above methods? I'm looking for a quick and not necessarily super precise way of doing it...and a way that doesn't involve advance programming skills as mine are very basic.

Thanks so much for any help!!

but I just want one number back and I'm really not sure how to get that out from that tutorial...it seems like only this weird graph thing is possible

You are getting lots of numbers back and they change over time and that is what the graph is. That is what you will have to cope with if you want to do this project. In that project the frequency is being swept over a range of frequencies an there is a different changing number from each frequency.

There is nothing that will give you a solid non-changing repeatable number when you touch one specific part.

There is the capacitive touch sensor on SparkFun but that just seems to give you a yes or no if something is touched and not a varied number based on how you touch that thing.

It is making a yes / no decision based on a threshold from the numbers you get back. You could plot them as a graph if you want.

Thanks so much for the help. I guess then my real question is how to get data that makes any sense on the threshold readings from the capacitive sensor boards? almost something like you would get from an FSR... anyone have any idea on this? i really can't find anything i understand online...a lot of it seems to be in a machine code or something... thanks!

i really can't find anything i understand online

When in doubt go directly to the data sheet. In this case the MPR121 Proximity Detector. This will tell you what registers inside this chip actually do. Two of these registers control the Touch / Release threshold. There are proximity registers as well.

However as I said what you are trying to do is "hairy" to say the least but it can be done. A few years ago I saw an installation with a selection of trailing plants coming down from a low ceiling. You stroked them and it produced tinkling noises. Unfortunately the artist could not or would not engage in any technical questions but it looked easy enough, just don't expect any sort of resolution.