Society of Robots - Robot Forum

Electronics => Electronics => Topic started by: mstacho on January 13, 2011, 09:53:04 AM

Title: Axon and resistive force sensor
Post by: mstacho on January 13, 2011, 09:53:04 AM

I'm thinking of getting a few resistive force sensors -- the ones that change their resistance when a force is applied.  In order to read from them, I'd have to supply a voltage, is that right?  Can the axon just read resistance at its analog inputs, or do I have to make a reading circuit for the sensor that measures voltage drop across it?

MIKE

Title: Re: Axon and resistive force sensor
Post by: Admin on January 13, 2011, 10:09:48 AM

ADC only reads voltage, so you need to create a voltage divider to know resistance.

Follow this tutorial:
http://www.societyofrobots.com/schematics_photoresistor.shtml (http://www.societyofrobots.com/schematics_photoresistor.shtml)

but instead of light changing resistance, you have force changing resistance. Works exactly the same.

Also good reading:
http://www.societyofrobots.com/sensors_forcetorque.shtml (http://www.societyofrobots.com/sensors_forcetorque.shtml)

If the signal is very small, you'll need to amplify it using an Op-Amp, or a Wheatstone bridge.