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Brad Fitzpatrick

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Steadycam for my laptop [Jan. 29th, 2008|07:53 am]
Brad Fitzpatrick
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My laptop has a camera, pointing at my face, and an accelerometer.

The shuttle is bumpy (well, in the city).

Between it doing some sort of head-to-screen relativity with the camera and feeling bumps with the accelerometer, I want it to rapidly pan the screen around, compensating for the bumps, making the text I'm always reading stable.

Too much to ask?

From: elvenforever
2008-01-29 03:59 pm (UTC)
Not unless you were really into Cloverfield. :)
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From: selfmade
2008-01-29 04:13 pm (UTC)
Possible if your accelerometer is 3D.
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From: evan
2008-01-29 04:20 pm (UTC)
There's a guy on the Mission shuttle who keeps his laptop in a briefcase-y thing that keeps a large stabilization pad beneath the laptop.

I think the tricky part about stabilization is that you need to move the text pretty fast in response to a bump, and vision algorithms often have latency.

The person to talk to at work is Glen -- he made http://freelook.org/ .
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[User Picture]From: nick
2008-01-29 04:42 pm (UTC)
You need a mechanical damper with the same spring constant as your body. Just experiment with different thicknesses of foam. Either that or you need a helmet mounted projector...
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[User Picture]From: redhotpenguin
2008-01-29 10:12 pm (UTC)

API issues not withstanding, might be too much to ask.

"In at least one model of Intel-based laptop, the MacBook Pro 15", Apple uses the Kionix KXM52-1050 three-axis accelerometer chip, with dynamic range of +/- 2g and bandwidth up to 1.5KHz."

1.5Hz should be well within the range of the bumps you are experiencing. The bumps are likely within the range of 50-200Hz. If your laptop is on your lap, your legs will act as a pivot moving the laptop up and down while your head experiences relatively little motion since it is rigidly attached to your body.

The problem though, is that your body will move slightly in relation to the laptop, so while you may be able to keep the text stable relative its previous position, you don't have an accelerometer on your body to measure the relative motion of your head to the laptop. If you put an accelerometer on your head, or can somehow use the camera to measure the relative displacement of your head, it might work.

Another issue to consider is displacement. If a bump displaces your laptop 4 inches, the text may remain in the same place, but it will be forced to displace off your screen to maintain that placement.
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[User Picture]From: mbrubeck
2008-01-30 12:25 am (UTC)
Something like Johnny Chung Lee's Wiimote head tracking might be able to do this.
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[User Picture]From: gregw
2008-01-30 12:30 am (UTC)
With the proper hardware, sure.
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