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Touch floor data sensors

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kentman234

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Hello,

I need your help in a project I do. We’re in need for touch floor data input, in order to detect presence/ movement of people across the building. Our initial concept was to measure capacities of sensors within rectangular grid. We found some chip (which was intended for small touch screens) - this chip works well for few sensors that are very close to the chip itself (in terms of wiring), however it is not usable for real scale (ie room 5 x 5 metres with ie 256 sensors or more). Can you help me to come up with something?
 
When I was in University in the 70's, I worked part time for the Earth Sciences dept and developed portable Seismic equipment using geophones for accelerometers. In a room of the same size I could flex my knees on the concrete floor and peg the needle on the concrete floor while the building HVAC motors caused some some rumble at lower levels. We could see a deer walking down the road 100m away and get impulses.

With the right notch filters for ambient resonances, you can detect movement for the whole room. To detect silent motion, you might consider standard IR motion detectors with narrow beam width. Or create a grid of remote control emitters from one controller and a grid of detectors to detect motion , just above the floor level. Each emitter and detector must be recessed for very narrow beamwidth with no overlap. THere may be some deadspots. For static heat sensing, use PIR sensors.

What resolution do you need?

For Wii games they have a touch sensitive sheet of plastic 1.5 x2m that interfaces for dance games but only 1 person.
 
When I was in University in the 70's, I worked part time for the Earth Sciences dept and developed portable Seismic equipment using geophones for accelerometers. In a room of the same size I could flex my knees on the concrete floor and peg the needle on the concrete floor while the building HVAC motors caused some some rumble at lower levels. We could see a deer walking down the road 100m away and get impulses.

With the right notch filters for ambient resonances, you can detect movement for the whole room. To detect silent motion, you might consider standard IR motion detectors with narrow beam width. Or create a grid of remote control emitters from one controller and a grid of detectors to detect motion , just above the floor level. Each emitter and detector must be recessed for very narrow beamwidth with no overlap. THere may be some deadspots. For static heat sensing, use PIR sensors.

What resolution do you need?

For Wii games they have a touch sensitive sheet of plastic 1.5 x2m that interfaces for dance games but only 1 person.

Thank you for the feedback. As you asked me about the resolution: It is room 5 x 5 metres with sensor grid with 200mm spacing.
 
WHat's your budget for this project and timeline?
 
is this an experiment or a permanent solution?
 
Did you pick Interlink FSR's?
Then adhere to Marley Dance flooring and put over very high density polyurethane carpet underlay.

Wiring using FPC cables under the underlay protected from friction.

Cost ~ $100/m^2
 
If you need 0.2m or 25 sensors / 1m²and 25 m², that becomes 625 sensors. ok?

A 5m flexible printed circuit (FPC) is commonly used for SMD LEDs is a durable polyamide could contain 25 strain guages with addressable uC signal processors on a shared high speed bus.

But the challenge is more mechanical than electrical to protect the device from breakage but adhere them rigidly to detect strain. It needs to be rugged on the top layer yet flexible enough to detect strain. Then the adhesion to the underside must be stronger than the stress applied so it needs stress relief underlay .

http://www.tactonic.com/floorTiles.html has 2' x2' floor tiles. which are not good enough.
THis company http://hpi.de/baudisch/projects.html has a Microsoft funded project with a glass touch floor and display.

Also IBM already has a patent on the application.
 
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