"Force Sensor Design and Calibration"

Summer Research Internship
Assistive Robotics Lab (June'16 - Aug'16)
Virginia Tech University, USA
Guide - Dr. Alan Asbeck

A force sensor based on cantilever bending was designed, fabricated and calibrated. Suitable dimensions of the cantilever beam was chosen based on the calculations using equations shown in the spreadsheet.

A LED was placed next to the free end of the cantilever beam towards the support structure. A phototransistor is placed on the other side of the free end of the beam.

When a load is applied on the loop hanging from around the center of the beam, the beam bends and blocks the light to an amount proportional to the load.

The phototransistor is connected to an Arduino and we can read the voltages corresponding to the amount of bending in the beam.

​The point of load application, design parameters are chosen, so that a wide range of forces can be applied for which there is a significant voltage change correspondingly. This translation was mapped and force was thus computed.