Arduino & Peltier Temperature Device Help

Hi guys, I'm very new to electronics and coding in general, so struggling with a Uni assignment a bit.

I'm attempting to create a one off device that allows you to touch and feel the current temperature of a location specified by my code.

In addition to the tactile feedback, I also want to create a visual feedback through 4-8 RGB LED's that change colour depending on the temperature range.

I have most of the components, which I'll include below, but I'm struggling to begin the build process of the project.

I've used the below article to connect my peltier to my arduino. But I'm struggling to figure out how to connect my temperature gauge so that I can test degrees accuracy. Also how to hook up an RGB LED to show the changes in degrees, courtesy of my temperature sensor.

I'm loathe to accidentally fry my board or any other components, so if anyone could give me a hand it'd be very appreciated.

As mentioned, I'm very new to this, so if it's a simple and possibly stupidly obvious solution, bear with me.

Thank you.

Peltier Article: http://garagelab.com/profiles/blogs/how-to-use-a-peltier-with-arduino

Components:
Freetronics EtherTen (Arduino Uno R3-compatible with Ethernet)
12V Peltier Module
12V Fan w/ Copper Heatsink
IRLB8721PBF N-channel power MOSFET - 30V / 60A
5mm LED RGB - Common Cathode
20 Value Resistor Kit
7805 +5V 1A Voltage Regulator
12V Powerpoint Supply
Prototyping Breadboard (30slots)
Female to male, m to m, f to f headers.

If you want to both heat and cool the touch surface then you need to be able to reverse the current flow (i.e. you need an H-bridge AKA "motor controller"). And mind you it doesn't take much current at all to detect the change in temperature on a peltier; with even a single AA battery you'll quickly notice the temperature change. Also, I'll wager that your 12V peltier is capable of much more power than you'll ever need; you should drive it with a lower voltage supply.

A DS18B20 temperature sensor is the typical solution (~$3 USD). If you want to stay cheaper then you can use a thermistor.

When you want to combine a temperature sensor and heating/cooling element then you should look at using the PID library.

What temperature sensor are you using?

" and feel the current temperature of a location specified by my code."

Are you proposing to measure the temp at a remote place and reproduce that temperature on your peltier?

What current does the peltier draw? Usually it is fairly high.

To light your LEDs, you simply select a band of temperatures for each colour and if the temperature is within the band, turn on the LED.

If temp < 10 then turn on blue
If temp > 10 & < 20 turn on green
Etc

Weedpharma

Disregard guys, sorry but I've had to put this idea on hold for the time being. Thanks for your consideration though.

Hi,
this bit worries me these days.

I'm very new to electronics and coding in general, so struggling with a Uni assignment a bit.

Uni assignment and no knowledge of how to approach it, even have a handfull of parts and still no idea.
Not even programming experience, when I was in "Uni" the first year, first semester we were taught Fortran, a programming language, so we could use Kronos, to solve our project assignments.

(I know, When I was a lad......down t pit...)

Tom...... :slight_smile: