Yesterday we studied how to detect Galvanic Skin Response GSR with Arduino.

Today we are going to see how we can use this knowledge to build a simple Arduino based Lie detector.

I found two projects that made sense about the subject.

Actually I have a certain criteria for choosing what projects to post.

First:

There must be scientific and practical credibility for the project.

I mean that it must be real, well written and well researched.

Second:

It must be easy to build and to realize.

Easy doesn't mean with no effort. But easy means that it can be built by following the steps as stated in the project.

That's what I found in those two projects here.

First Project

This project makes the GSR analysis with Arduino and then gives the result on one of two LEDs. Green or RED.

Circuit

Code

void setup()
{
	Serial.begin(9600);
	pinMode(2, OUTPUT);
	pinMode(3, OUTPUT);
	pinMode(4, OUTPUT);
	digitalWrite(2, HIGH);
	delay(500);
	digitalWrite(3, HIGH);
	delay(500);
	digitalWrite(4, HIGH);
	delay(500);
}

void loop()
{
	if (analogRead(A0) > 60)
	{
		digitalWrite(4, HIGH);
	}
	else
	{
		digitalWrite(4, LOW);
	}
	if (analogRead(A0) > 20)
	{
		digitalWrite(2, HIGH);
	}
	else
	{
		digitalWrite(2, LOW);
	}
	if (analogRead(A0) > 45)
	{
		digitalWrite(3, HIGH);
	}
	else
	{
		digitalWrite(3, LOW);
	}

	Serial.println(analogRead(A0));
	delay(20);
}

Second Project

This project uses temperature sensor to measure skin temperature as one of important parameters of biofeedback.

The project displays the result on an LCD and can also display results of GSR analysis on Processing code just as in yesterday project.

Circuit