GSR Skin Sensor

A GSR Skin Sensor (Galvanic Skin Response Sensor) is used to measure the electrical conductance of the skin, which varies based on the skin's moisture level. It's widely used in biofeedback, lie detector tests, stress detection, and emotional state monitoring.

How GSR Works:

• Our skin contains sweat glands, and their activity increases with stress or arousal.
• When a person is stressed or emotionally excited, sweat secretion increases, which lowers skin resistance and increases conductance.
• The GSR sensor typically consists of two electrodes attached to the fingers or palm.
• A small voltage is applied, and the sensor measures the resistance or conductance between the electrodes.

Typical Features of a GSR Sensor Module:

1. Two Electrodes (often stainless steel plates)
2. Amplifier Circuit (usually uses an Op-Amp like LM324)
3. Output:
   • Analog Output: Proportional to skin resistance/conductance.
   • Digital Output: Some modules have a threshold-adjustable comparator for a digital high/low signal.
4. Operating Voltage: 3.3V – 5V (suitable for Arduino, Raspberry Pi, etc.)