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-   -   fcam team has experimental gyroscope for n900 (https://talk.maemo.org/showthread.php?t=58906)

quipper8 2010-07-21 21:01

fcam team has experimental gyroscope for n900
 
1 Attachment(s)
http://www.graphics.stanford.edu/papers/fcam/fcam.pdf

and

http://www.graphics.stanford.edu/papers/fcam/fcam.mov

"Our
Lucky Imaging application uses an experimental Nokia 3-axis
gyroscope affxed to the front of the N900 to detect hand shake.
....
We use an external gyroscope because the internal
accelerometer in the N900 is not suffciently accurate for this task"


Does anyone have more info how this is working, over USB? maybe look at fcam source to see how it is communicatiing with gyroscope?

They say this is nokia experimental, but is there anything out there comparable that is available?

thanks, just curious

lcuk 2010-07-21 21:12

Re: fcam team has experimental gyroscope for n900
 
depending on how often they are checking the onboard accelerometer and whether they are using the smoothed interface I could almost believe them
but I rarely see unexpected jitter ;)

Dunno where the outboard is from, looks interesting though

danramos 2010-07-21 21:14

Re: fcam team has experimental gyroscope for n900
 
Wow. An accessory. Finally. Now, can anyone get one to play with and use it for development? No? Thought so.

Kingsley 2010-07-21 21:24

Re: fcam team has experimental gyroscope for n900
 
that gyro application is pretty cool, and thi short-long exposure alternation on the panorama too!

danramos 2010-07-21 21:41

Re: fcam team has experimental gyroscope for n900
 
It's great--but it's all pointless unless and until it's actually released. There'll certainly be a lack of apps until at LEAST developers see it.

joerg_rw 2010-07-21 21:42

Re: fcam team has experimental gyroscope for n900
 
Quote:

Originally Posted by quipper8 (Post 759904)
We use an external gyroscope because the internal
accelerometer in the N900 is not suffciently accurate for this task"

quite nonsensical. The builtin is an accelerometer and thus incapable by design and by concept to detect shaking relevant for camera.

A gyro is not an accelerometer aka g-meterThey are complementary, each one is sensing the movement the other one can't detect.

So the rationale given is extremely missleading


For the connecting topic I'd guess they exploit some of the testpads under battery. If source can tell details, I'd be highly interested. Don't think they are using a USB hostmode fixed to working state en passant.

/jOERG

quipper8 2010-07-21 21:47

Re: fcam team has experimental gyroscope for n900
 
Quote:

Originally Posted by joerg_rw (Post 759949)

For the connecting topic I'd guess they exploit some of the testpads under battery. If source can tell details, I'd be highly interested. Don't think they are using a USB hostmode fixed to working state en passant.

/jOERG

yes, this is what I am most interested in, how are they getting output from gyro into phone

Creamy Goodness 2010-07-21 21:56

Re: fcam team has experimental gyroscope for n900
 
cool. i have faith there are some huge frankenstein bolts connecting it to the phone.

abadams 2010-07-21 22:02

Re: fcam team has experimental gyroscope for n900
 
Hi all,

I'm one of the Stanford guys involved in the project. The external gyro is something Nokia Research got made to test gyroscope-using apps. It communicates to the phone over bluetooth with timestamped 3-axis angular velocities. Unfortunately the bluetooth communication isn't hugely reliable, even at such a short distance, and the whole app was a little flaky as a result.

We referred to the built-in accelerometer as insufficiently accurate because a) accelerometers don't detect rotations of the camera that cause blur (i.e. joerg_rw is right), only the linear accelerations (which are usually less of a problem), and b) we needed a fairly high data rate and high precision to detect the small movements that cause a several-pixel blur in the output image.

Our most recent version of this app just directly looks for sharp edges in images, and seems to work more reliably (it's included in fcamera as the best-of-8 burst mode). Oh well :)

- Andrew

danramos 2010-08-02 22:12

Re: fcam team has experimental gyroscope for n900
 
As usual, Microsoft comes along and claims they're pioneering something someone else (often, everyone else) has already been doing long before they "invent" it:

http://www.crunchgear.com/2010/08/02...-during-shots/

Sounds a lot like YOUR work. Grrrr


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