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CrazyIgels
Joined: 26 Oct 2007 Posts: 79
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Posted: Mon Jun 06, 2011 3:49 pm Post subject: Radio frequency based proximity sensor |
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Hello all!
I have task - i need to invent some device to sense human hand and measure distance from hand to sensor.
Sensing range - from 1 cm to 1 m. Accuracy - something like 2 - 3 cm.
And digital output - string on serial port like "X=10;Y=10" where "10" its current distance from first human hand to sensor.
Yes, sensor must have two axis. Possible to use two or more passive sensing devise (receiver antennas) and active device in hand (transmitter)
And also i need to sense two humans. I attach drawing.
And also i need a good speed of position measurement - something like 100 measures per sec.
I think - using radio frequency - something like "theremin"
http://www.youtube.com/watch?v=L_cXAoYUGdU
but i dont have many space for large antennas
Please - give me any ideas - radio frequency schematics - its not to easy for me
Thanks All
Sorry my bad english |
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AdrianJ
Joined: 16 Jan 2006 Posts: 2483 Location: Queensland
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Posted: Mon Jun 06, 2011 11:16 pm Post subject: |
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I think you should post this in the "Various" forum, or indeed somewhere like sci.electronics.design. At this stage it has nothing to do with AVR or Bascom.
From your requirements, I would be thinking about a video capture system, and image recognition. I doubt any form of RF sensing would work. _________________ Adrian Jansen
Computer language is a framework for creativity |
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hgrueneis
Joined: 04 Apr 2009 Posts: 902 Location: A-4786 Brunnenthal
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Posted: Mon Jun 06, 2011 11:24 pm Post subject: |
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Either way it is going to be a very involved project.
Should probably be posted in the "VARIOUS" section of the forum (no BASCOM code yet).
The movie industry uses a video spatial position acquisition for the creation of animation from real movement.
In your case you could set a color camera above, use two different color reflective markers and digitize the video image.
Depending on the camera and digitizer you would be able to get enough samples per second.
Of course you will need a controller to process the digitized video into two x/y positions.
An other possibility could be position calibrated acceleration meters (2D or 3D) with low power wireless interface.
If RF is used, there is always the problem of testing and certification in most countries.
Maybe it gives you a starting point.
Hubert |
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CrazyIgels
Joined: 26 Oct 2007 Posts: 79
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Posted: Tue Jun 07, 2011 8:16 am Post subject: |
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We try video recognition system and markers - very hard to calibrate and to much sense to external light. In dark room work fine, in light room - don't work with good stability.
Also we try WII MotionPlus sensor - to hard to implement in project. |
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AdrianJ
Joined: 16 Jan 2006 Posts: 2483 Location: Queensland
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Posted: Tue Jun 07, 2011 11:36 pm Post subject: |
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Carrying on with the video system a bit further. Did you think about using IR illumination, and filters on the detectors to cut out the ambient light ? _________________ Adrian Jansen
Computer language is a framework for creativity |
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concon
Joined: 12 Nov 2011 Posts: 3
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Posted: Wed Aug 01, 2012 5:27 pm Post subject: azoteq |
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maybe your problem solution; www.azoteq.com
sorry for later answer |
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