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Prop Vision. — Parallax Forums

Prop Vision.

Peter J. FischelPeter J. Fischel Posts: 28
edited 2009-02-06 21:17 in Propeller 1
So, I was reading a thread about Quadrocopters and I god to thinking about how the best way to hold them into position.

This got me thinking about·optical mice. Obviously there must be some quasi vision system that "sees" small movements on a surface and returns the motion back to the computer.

What if you took some vision chip that you could read like memory and started reading bands of data so that you could aproximate motion? Seems black/white would be a good choice. If you could convert intensity spots as a way to see if the craft is moving, you might better hold it in position.· Even low res would seem fine for this.

Has anyone tried this here? Anyone have suggestions?· Also if someone knows of a good video chip for such an experiment I would appreciate it.· I would think a video chip that you could read the memory directly would be best.

Thanks,

Peter

Comments

  • simonlsimonl Posts: 866
    edited 2009-02-05 13:18
    @Peter: Yup - why not use the innards of an optical mouse, with a longer focal length? I've seen a few sites where it's been done. This is the one I have a link for: hackaday.com/2006/01/29/robotic-motion-sensing-using-an-optical-mouse/

    PhiPi has also done motion sensing using his "PropCAM", but he never got around to releasing it (even though he spent shed loads on lenses and sensors!)

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    Cheers,
    Simon

    www.norfolkhelicopterclub.com

    You'll always have as many take-offs as landings, the trick is to be sure you can take-off again wink.gif
    BTW: I type as I'm thinking, so please don't take any offence at my writing style smile.gif
  • virtuPICvirtuPIC Posts: 193
    edited 2009-02-05 14:20
    Yeah, I also thought about using mouse sensors as cameras. There are a number of projects on the net. See e.g. the links on www.hackszine.com/blog/archive/2007/12/using_an_optical_mouse_for_rob.html?CMP=OTC-7G2N43923558.

    However, usually you only get 18 x 18 pixels. If you want to scan more distant than one or two millimeters than you alos have to assemble the optics. I will look at MT9M001 / MT9M031 sensors delivering digitized megapixels at reasonable speed and moderate price - if your interface can handle the data rates.

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    Airspace V - international hangar flying!
    www.airspace-v.com/ggadgets for tools & toys
  • Peter J. FischelPeter J. Fischel Posts: 28
    edited 2009-02-05 15:24
    That sounds like a good way to make sure my boebot is on track. The mouse idea. Now to find me a mouse to di-sect (sp)
  • virtuPICvirtuPIC Posts: 193
    edited 2009-02-05 15:51
    Well, if 'on track' means following some marks that can be recognized by a linear array search for 'TSL201R-LF' at mouser.com and get de.mouser.com/Search/Refine.aspx?N=10989873&Keyword=TSL201R-LF&Ns=Pricing|0&FS=True. 64 sensors at 200 dpi in a row at the price of a mouse...

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Airspace V - international hangar flying!
    www.airspace-v.com/ggadgets for tools & toys
  • Chad GeorgeChad George Posts: 138
    edited 2009-02-05 16:16
    My propeller based sumo bot has an optical mouse built into the base.

    http://forums.parallax.com/showthread.php?p=661158

    I still have some PCBs, robot frames and the parts for the mouse sensor (although I'm out of almost everything else.
  • JasonDorieJasonDorie Posts: 1,930
    edited 2009-02-06 04:50
    A lot of the public quad copters make use of 'horizon sensing' - basically they use thermopiles or some other form of infra-red detector to figure out how much 'ground vs sky' is in the field of view from one side of the bot, and attempt to balance that with the sensors providing the same data from the other sides of the bot. This works really well in open fields, but less well close to anything tall and man-made. [noparse]:)[/noparse]

    Jason
  • rjo_rjo_ Posts: 1,825
    edited 2009-02-06 21:17
    http://mydancebot.com/kits/s.php?k=camera

    haven't ordered this yet... and I really can't tell what you can do with this in a propeller only environment... interested to find out though...

    Rich
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