Arduino as Capacitive Sensor

alright! First off, thank you thank you so much for at least putting the effort! I really really appreciate it! So i have run the code with the revisions, and i get a small light up from the LED...

i believe the serial monitor is giving me the highest value of 4 when i touch the wire...and so i tried putting that code

Ok, yes my value was a bit high then but it changes with the resistor. If you put in a larger value resistor then you get much bigger numbers and you can sense proximity to the sensor. This varies quite bit though due to where your body is/who else is in the room!

Glad the code works for you.

out of curiosity, how can i make the more visible?

i really really appreciate all your help!

If you change the ledPin to another pin, 8 for example then you can put in your own LED with a resistor from that pin to ground (Gnd - next to pin 13). The on board LED cannot be any brighter, it is just there as an indicator for testing.

Mowcius

The LED should light up bright when the digitalWrite(ledPin, HIGH) function is called. If the led is dim, you either have too large a resistor in series with the LED, or you have not declared that the ledPin is an output pin.

Can you post your code, and describe (or show) the hardware setup?

Oh come on, RTT (read the thread). It has been stated clearly that the on board LED (13) is being used and therefore it cannot be made brighter.

Mowcius

thanks for all the help!

hopefully this will work to turn on a projector! I was planning on using an IR light in place of the LED and when the wire was touched, the IR light would flash, and would turn on the pico 2 projector....

just wish the IR light was stronger....

How do you know that the IR light isn't "bright" enough? You can't see it.

the IR LED usually is a bright bright flash...but when i touch the wire, there is a dimmer glow

the IR LED usually is a bright bright flash...but when i touch the wire, there is a dimmer glow

if you are still using it on pin 13 then move it to a different pin. Pin 13 already has resistor on it which may not be suitable for the LED you are using/have. Make sure you put in a suitable resistor for the LED if you do move it to another pin though.

Mowcius

@Mowcius

OMG IT WORRRRKS!!! The light is soo much stronger!!! Thank you thank you!!!
:smiley:

now the next obstacle i must tackle is the following:

I need to make this IR light able to turn on a Pico 2 projector. Now i discovered that the projector comes with an IR remote control. So i intend to replace that remote and use this device i just built for that. I also discovered that the IR remote that comes with the projector is MP4....would that be something of use?

also, i think i found code for the "IR" tv translation and looks like this:

brand(PHILIPSTV) ;
button(POWER,2) ; // hello world
delay(15000) ;
button(ZERO,2) ; // change channel to 03
delay(100) ;
button(THREE,2) ;
delay(100) ;
button(MUTE,2) ; // mute the TV
delay(15000) ;
button(POWER,2) ; // over and out

I know the brand isnt right, but does arduino have a code for MP4? and if so, where would i put it?

OMG IT WORRRRKS!!! The light is soo much stronger!!! Thank you thank you!!!

Well I wouldn't have said it if I thought it wouldn't work :wink:

I need to make this IR light able to turn on a Pico 2 projector. Now i discovered that the projector comes with an IR remote control. So i intend to replace that remote and use this device i just built for that. I also discovered that the IR remote that comes with the projector is MP4....would that be something of use?

also, i think i found code for the "IR" tv translation and looks like this:

Ok, I'm afraid that my knowledge does not extend very far into IR stuff.

I would like to try this, but a bit about my application.

I'm trying to create a midi bend up and midi bend down plate on either side of the right thumb for an "Electronic Wind Instrument" application.

What I need is for each of those sensors to return a value of 0 - 128) smoothly, as a function of how much skin is touching a piece of copper about a 1/2" square.

No skin contact needs to equal 0, and then as the thumb is rolled slowly onto the capacitance sensor, I need a smooth rise up to 128.

Is this even possible? Because I will not investigate this further if it is not even possible.

CD

Thanks.

It is relatively easy to measure the distance of someone's hand away from the sensor and map that value from 0-128 but it is not very easy to do it for the amount of skin touching the 'pad'. The capacitance measured would be very small differences so it would need to be very accurate. This would then change from person to person and humidity etc.

I think you may be better off with a force sensor...

Mowcius

Hi,
I was to ask please how do I get the output to an LED or how do I observe the output

This looks remarkably like spam. Maybe we'd better watch it.

If not, then I don't understand the question and this isn't the right place to post it.

Hi,
I have done this experiment on capacitive sensing using the available codes on this page. Can anyone tell me how to convert the signals to the motion of a cursor on my computer so that when I move my hand around the cooking foil (sensors) the cursor will also move. Same as a mouse motion :slight_smile:

I just want to say thank you!
I've been playing with this, it's quite interesting taking measurements of various things and testing different sized sensors.
Eventually it'll find it's way into a paranoid robot that runs away when you try to pick it up :smiley:

Bobnova,
please can you give me an idea i don't have the slightest idea on how to make the magic work :wink:

please can you give me an idea i don't have the slightest idea on how to make the magic work

I'm sure you told me you had it working with the one sensor?

Then just add another, get it to send serial and then use some software on your computer to convert it into very innacurate mouse movements.

Mowcius

Ok thanks mowcius. where do i connect the second sensor to

sorry, i mean what pin on the ardiuno do i connect the second sensor

Which ever pin you like.

You then just have to add it in the code.

Hello all,

I am currently working with the CapSense library to create capacitive sensors with Arduino. I managed to make some sensors (made of copper wire) work but I will need 16 sensors (there are no enough digital pins for that). Does anyone have experience with using a 4051 or 4067 analog multiplexer with capacitive sensing?

Thanks in advance.

PS. The sensors do not have to output super-precise values.