GSR sensor interfacing | Arduino code and Block Schematic
This page covers GSR sensor interfacing with arduino code. It describes GSR sensor interfacing block circuit schematic.
Introduction: EDA (Electro Dermal Activity) is the property of human body which refers to electric characteristics of pores and skin. As per EDA principle, pores and skin resistance varies with state of sweat glands inside the skin. Sweating is managed by our nervous system and skin conductane is sign of physiological arousal.
What is GSR sensor ?
GSR stands for Galvanic Skin Response. The GSR sensor is used to measure electrical conductance of the skin. The sensor consists of two electrodes put on the two fingers of one hand. The GSR sensors are used to monitor sleep quality and to measure emotional arousal. The GSR sensor is kind of ohmmeter as it measures the electric conductance between the two points.
Sweat glands of our body are controlled by nervous system. Due to different states of emotions such as stressed or relaxed, sweat produced by these glands vary. Skin conductivity changes as per secretion of sweat. Change in conductivity can be measured by measuring the voltage.
When skin resistance is high, conductive voltage is low and vice versa. To have good results, electrodes are placed on index and middle fingers due to less hair and skin thickness.
The GSR sensors from Seeed Technology Co., Ltd. include Grove GSR v1.0 and Grove GSR v1.2. The part number SKU: 078-101020052 is GSR sensor from Seeed Studio. In India it is distributed by Evelta Electronics, Mumbai.
GSR sensor interfacing with Arduino block circuit schematic
The GSR sensor requires 5V for its operation. The data is acquired within range of 1 to 10 Hz. GSR signal is based on conductance which is inverse to skin resistance. Refer working operation of GSR sensor >>.
Following table mentions connections between GSR sensor and Arduino board.
|GSR sensor||Arduino Uno Board|
GSR sensor interfacing with Arduino code
Following is the arduino code to interface GSR sensor with arduino UNO or Arduino Mega board. Once this code is compiled and run, it reads the sensor value from GSR sensor at analog pin A0 of arduino board. The code reads the analog data (in the range from 0 to 1023) and convert it to analog voltage in the range from 0 to 5 V. The converted voltage is displayed on the serial monitor. The serial communication speed is set initially to 9600 bps.
const int GSR=A0;
conductivevoltage = sensorValue*(5.0/1023.0);