This tutorial is going to teach you some basics on using Force Sensitive Resistor or also known as FSR.
Step 1: Introduction
This is a force sensitive resistor with a round, 0.5" diameter, sensing area. This FSR will vary its resistance depending on how much pressure is being applied to the sensing area. The harder the force, the lower the resistance. When no pressure is being applied to the FSR its resistance will be larger than 1MΩ. This FSR can sense applied force anywhere in the range of 100g-10kg.
Two pins extend from the bottom of the sensor with 0.1" pitch making it bread board friendly. There is a peel-and-stick rubber backing on the other side of the sensing area to mount the FSR. These sensors are simple to set up and great for sensing pressure, but they aren't incredibly accurate. Use them to sense if it's being squeezed, but you may not want to use it as a scale.
Force Sensitivity Range: 100g to 10kg (depends on mechanics)
Pressure Sensitivity Range: 1.5psi to 150psi (depends on mechanics)
Stand-off Resistance: >1MΩ
Overall Length: 2.375''
Overall Width: 0.75''
Sensing Diameter: 0.5''
Step 2: Sample Hardware Installation
Step 3: Sample Schematic
The above pictures shows one example for the connection of the components.
*The value of R1 does not necessarily have to be 3.3k, it can also be other values as long as the value of resistance is available in real life.
Step 4: Sample Source Code
To get the result, please download the sample source code attached below and upload it into Arduino.
*Kindly download the FSR Integration Guide for your own reference and also to understand the coding written better.
Step 5: Result (1)
When no pressure is being applied to the Force Sensitive Resistor.
Step 6: Result (2)
When the Force Sensitive Resistor is being pressed gently.
Step 7: Result (3)
When the Force Sensitive Resistor is being pressed hardly.