How to use a strain gauge with an arduino to output a voltage into a polymer

Other Hardware Sensors
1

Hey everyone, I'm new to this forum and I have a question.

I'm working on a project in college to design a knee sports armor. Not just any armor, but the kind that is made up of a certain type of electro-active polymer material (we don't know what kind or what composite it would be made out of just yet).

This projects goal, in the end, is to help college athletes (playing football, soccer, etc) prevent major MCL (medial collateral ligament) tears. This would happen when there is an impact on the lateral side of the knee which causes a valgus motion and puts a high strain on the MCL and, in the end, causing it to tear.

My part of the project would be to somehow use an array of strain gauges on the medial side of the knee to sense about a 2% strain and therefore, using an arduino, send a voltage or current out into the polymer material causing it to stiffen up and prevent any type of injury when the knee is impacted. All of these devices must be embedded within the polymer material of the armor. It shouldn't be a burden on the athletes legs/knees to run around with it.

The sensor may even be pressure sensing. It just needs to be able to convert that energy into a voltage by an arduino or something of the sort that carries out that voltage into the polymer material

I am a Biomedical Engineer, and all of this Electrical stuff really confuses me, so if any of you can give me some guidance on how I might be able to do this, I would totally appreciate it!

Please let me know!

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A strain gauge is normally glued with epoxy glue to a metal.
Do you want to attach a strain gauge to a soft material ?

Or perhaps a force resistor is needed here ?

Or a piezo PVDF ?

What about some kind of buttons ? Like the foil buttons used in many keyboards. It the button is mechanically constructed to connect with a certain force, that could mechanically be set to the force you need to make the polymer active.

You could start with an Arduino Uno to test everything.
To make it smaller, you can replace the Uno with an Arduino Nano or Arduino Pro Mini.

Could you try to get some numbers of the forces that are involved ? The polymer should get really strong really fast to be able to protect something.