Just a question of hardware(Flexible Buttons)

DiablodeMorte

I'm thinking about starting a project for my math teacher at school. I need about 100 flexible, flat, large area, bendable buttons(Yep. all those requirments). I'm pretty much trying to make rollable keyboard but i do need the buttons to be rather large(~1-4 inches(4X4)). I was wondering if anybody could point me in the right direction.

Regards

bulkhead

I don't exactly know how they do it, but you can check out the concept behind the "DDR pads" for playstation. Something like that may work, although I don't know how you would make 100 of them yourself.

Check out this post about force sensitive strips from a week or so ago: (from about 15 threads down)
http://forums.parallax.com/forums/default.aspx?f=15&m=108173

mediaprefect

I don't know what has happened to the company, but Pennwalt used to make a piezo plastic film (PVDF). It also exhibited pyro-electic properties. You could use it as a microphone, a speaker, a drum pad or in a PIR motion detector. Here is a source of technical info on it: www.media.mit.edu/resenv/classes/MAS836/Readings/MSI-techman.pdf
Check out the references at the end as a patent for use in a keyboard is listed.

An alternative technology is the the Flexpoint Bend Sensor from www.flexpoint.com They are variable resistors which change resistance as you bend them. Only 5/1000" thick
I found Flexpoint last year at the Sensors Show in Chicago, only a few booths away from Parallax. I believe that they are in the few dollar range at 100 pcs.

I hope this helps.

Rick