USU Get Away Special Team coded for measuring force on a flexiforce sensor. Output is in pounds
useful links:
http://www.circuitbasics.com/arduino-ohm-meter/
https://learn.adafruit.com/calibrating-sensors/why-calibrate
https://learn.adafruit.com/force-sensitive-resistor-fsr/using-an-fsr
Spreadsheet of our calibration data: https://docs.google.com/spreadsheets/d/10tPFQwyjGs_ZmfURZRNJRddiEuDQi94_oVZkXNPnRRg/edit#gid=0