Flexiforce Pressure Sensor - 25lbs (1'' area)
Last updated: 5 October 2012
Prepared by Vanissa Law [vanissalaw@gmail.com]
URL: https://www.sparkfun.com/products/11207
Cost per unit: $24.95 USD (approx.195 HKD)

General Information
About Flexiforce Pressure Sensor
Flexiforce Pressure Sensor is a piezoresistive forces sensor. The harder you press, the lower the sensor's resistance Pressing hard, the resistance changes from infinite to ~50K. The sensor itself is thin and flexible, but the resistance does not change while being flexed. Resistance changes only when pressure is applied to the round area at the end of the sensor. Used as a presence sensor (someone standing), weight sensor, pressure sensor (impact testing), etc.

Features & Specifications

Measurement range of 0-1 lb and 0-7000 lb are achievable with the A401 sensor by utilizing the recommended circuitry. The force range can be extended by reducing the drive voltage, or the resistance value of the feedback resistor. Conversely, the sensitivity can be increased for measurement of lower forces by increasing the drive voltage or the value of feedback resistor.

Getting it to work!


Routing readings into Max
1. Open Arduino software. From the "File" pulldown menu choose Examples> Firmata> AllInputsFirmata. Then upload the code onto your Arduino.
2. Open the "MaxuinoForLUME" patch/ Click the "print" message box on the grey panel. It will print all the available serial ports on your computer into the "umenu" underneath. Choose "usbmodem621" port to route serial data from Arduino into Max.
3. You should see readings routing thru Max and a MIDI note will be played when pressure is exerted on the sensor.