How to decrease fluctuations

[MartinV279]

For a project I've made flex sensors (using piezoresistive material). They pretty much do the job (give about 5 distinct resistance areas for determining position), but the fluctuations in the signal give me a problem. I was thinking of making a filter in the code, but stabilizing them through the hardware would be preferable I think. Any ideas or tips? Generally I don't need the small oscillations, only the greater ones.
Thanks!

 

[Arouse1973]

Can you tell us the frequency and amplitude of the oscillations? Better still post an oscilloscope capture here. A circuit diagram would also be good.
Adam

 

[MartinV279]

Thanks for the fast reply. I'm afraid I'll need a day or two to get my hands on the oscilloscope from the lab at uni.

 

[Arouse1973]

That's fine, it's better we see what going on. In the meantime maybe you can explain a bit more about the project and how it's designed to work and what it's for.
Adam

 

[MartinV279]

I'm making a sign language glove and due to budget deficit I'm using homemade sensors. They are made with velostat material from black conductive tapes. Due to imperfection because it's all hand made/cut/taped it's kind of unstable. So I'm trying to stabilize the signal with hardware. The alternative is to filter out all changes below 2% in the code, but I'm not a fan of software solutions if there's a hardware solution. I was thinking of a low pass filter (100nF capacitor) and then subtract the output of the filter from the output of the sensor.
The sensor give resistances in the range of 15kΩ-60kΩ. The nominal value is about 27kΩ.