Building an Arduino Torque Wrench....

Hello world!

Currently i am in a group project where im building an Arduino torque wrench. To my best understanding we are gonna install two strain gages on a 1/2 inch drive extension and connect the strain gauges to a SparkFun Load Cell Amplifier - HX711 (SEN-13230) where the torque will read out on a Basic 8x2 Character LCD - Black on Green 5V (LCD-11122). We are going to integrate a Vibration Motor (ROB-08449) and a Piezo Speaker - PC Mount 12mm 2.048kHz (COM-07950) so when the wrench gets to the desired torque then it will vibrate and beep at the same time.

  1. can anyone point me in the direction of finding the right strain gauge to install on a 1/2 inch extension????????

  2. any additional comments or suggestion would help me a ton.

Quite an ambitious project for a newbie.

The core of the project is the strain gauge and the load cell amplifier together with the Arduino and you should focus on these first. The display, vibration motor and speaker are extras.

Here are some ideas for the strain gauge:

www.omega.com/techref/pdf/STRAIN_GAGE_TECHNICAL_DATA.pdf

and maybe here:

Just incase you are still working on this...Are you aware of this?

I am going to try to buy a cheap digitial torque wrench and when the buzzer circuitry goes high to say the torque has been reached - I will sense that voltage on an Arduino so I can remove the tool with a motor. Not sure if/how to operate the buttons to set a given torque...I will see when it arrives I guess!
Good luck!