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Viewing 15 posts - 466 through 480 (of 522 total)
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  • in reply to: Proper location of BoxLayout.txt #100835
    Oliver Kreylos
    Keymaster

    Our instructions say not to install the SARndbox package, and run it from the source directory. It’s for simplicity’s sake.

    Let me get back to you on the autostart question. We’ve set it up that way for our partner institutions, but I didn’t do it, and don’t know right now what strategy we used.

    in reply to: Proper location of BoxLayout.txt #100832
    Oliver Kreylos
    Keymaster

    If you followed the default instructions, and did not install the SARndbox package after building it, i.e., if you did not run “make install,” then BoxLayout.txt needs to be put into ~/src/SARndbox-<version>/etc/SARndbox-<version> (assuming that ~/src is where you unpacked the source tarball).

    If you did install, then it needs to be in the etc/SARndbox-<version> directory in the location where you installed to, e.g., /usr/local.

    in reply to: Hardware requirements #100827
    Oliver Kreylos
    Keymaster

    The current version of the AR Sandbox software only supports first-generation Kinect devices.

    in reply to: Projector Calibration Question #100822
    Oliver Kreylos
    Keymaster

    That shouldn’t happen. Make sure that the display windows in CalibrateProjector and SARndbox are the exact same position and size, ideally both full-screen with no title bar or desktop panels showing. See this other thread on how to achieve that.

    in reply to: Kinect and projector same height? #100821
    Oliver Kreylos
    Keymaster

    No, that’s merely a convenience and a suggestion. There are two things to look out for:

    1. Your Kinect’s field of view should match the interior of the sandbox. You don’t want to waste any pixels by scanning the floor, and you don’t want to waste sandbox space by missing a few inches inside. Use RawKinectViewer to align the Kinect, and then lock it in place.
    2. Your projector should do the same, ideally project exactly onto the interior of the sandbox. If you have a zoom lens, set it to a medium zoom level for optimal image quality. Align the projector by displaying anything on the screen, or use the calibration pattern provided by Vrui’s XBackground utility, and then lock it in place.

    If those two are taken care of, where exactly your Kinect and projector end up doesn’t matter.

    in reply to: Will a Intel NUC cut the mustard? #100818
    Oliver Kreylos
    Keymaster

    I don’t know, but I guess there’s a good chance it will work — as long as you disable the water simulation, as you say. Without water, the AR Sandbox is not very demanding, graphics- and CPU-wise. You might get some OpenGL warnings because Intel’s on-board GPU works with the open-source Mesa OpenGL library, which has some issues, but those won’t break the code.

    Try it, and if it works, please press Win+Scroll Lock once you’re inside the SARndbox application. That will display a running frame rate average, and print an overall average frame rate to the terminal when you press Win+Scroll Lock again a few seconds later. Please report back with those numbers. As long as you get 60 or more frames per second, you will be fine.

    in reply to: General Question #100815
    Oliver Kreylos
    Keymaster

    I’m not sure what you mean by “structures,” but in general yes. The only thing that destroys calibration is moving the projector with respect to the camera, even by very little. Any time you do that you need to recalibrate. What you do to the sand won’t affect it.

    If you put any objects on top of or into the sand, such as Lego bricks or model trains, they will typically get picked up by the Kinect, and the software will interpret them as part of the sand surface (the software can’t distinguish sand from non-sand). So they will get integrated into the topography, the projector will colorize them based on their height and put contour lines onto them, and water will flow around them.

    in reply to: I don't speak Linux – Can I do this? #100811
    Oliver Kreylos
    Keymaster

    I’m the wrong person to answer this, but you should be fine. Installing Ubuntu Linux and the required graphics card drivers is very straightforward, and the sandbox software installation and setup instructions are very detailed. Use Vrui’s installation script instead of getting bogged down by that first step. As long as you’re not afraid of typing commands into a terminal, and follow the instructions, you’ll be OK.

    There’s no coding involved. The worst you’ll have to do is copypaste a few numbers into a text file.

    in reply to: Sand brand #100810
    Oliver Kreylos
    Keymaster

    Get the whitest sand you can find, ideally wash it before putting it into the sandbox to reduce the amount of dust (dust can interfere with the Kinect’s operation), and keep it slightly damp during use to make it more moldable. For Sandtastik sand, I recommend one cup of water per 200lb of sand (more or less). For coarser-grain sand (Sandtastik is very fine), you’ll have to experiment.

    in reply to: Feature wish list #100809
    Oliver Kreylos
    Keymaster

    For new questions, please start a new thread in the main forum.

    in reply to: Feature wish list #100804
    Oliver Kreylos
    Keymaster

    We’re using Kinetic sand in the AR sandboxes at Lawrence Hall of Science and ECHO. I personally don’t like it very much because it requires a bit too much effort to work (you can’t make a riverbed just by swiping your hand, for example), and it doesn’t take projection color very well because Kinetic sand, at least as of now, is naturally brown instead of white. The Kinect can read its surface just fine.

    in reply to: Display updates intermittent #100801
    Oliver Kreylos
    Keymaster

    One thing: what kind of laptops did you try, and how old were they?

    I have a 2008 Macbook Pro, and I have run into a similar issue with Kinect. The moment I stop moving the mouse/trackpad or stop pressing keys, the computer goes into a lower-power state, and in that state it’s not fast enough to keep up with the Kinect’s high data transmission rate. Plugging it into an AC outlet, or turning off power saving in laptop mode, fixes the issue. Have you by any chance tried any of that?

    in reply to: Display updates intermittent #100800
    Oliver Kreylos
    Keymaster

    I’ve heard about that problem a few times now, but I’ve never been able to replicate it, or figure out what could be causing it.

    Does the same happen when you run one of the non-Kinect / Sandbox Vrui applications, such as the ShowEarthModel one that’s part of Vrui’s example programs?

    in reply to: caught exceptions with RawKinectViewer and SARndbox #100799
    Oliver Kreylos
    Keymaster

    OK, then you had a broken USB host controller. That happens. The Kinect sends a lot of data over USB, and controllers that seem to work fine for keyboards or mice or webcams etc. might buckle under the load.

    in reply to: Problems with KinectViewer (calibration step 5) #100798
    Oliver Kreylos
    Keymaster

    If you remove the intrinsic calibration file, the Kinect package will fall back to a built-in default calibration, which isn’t good, but gets the basics going. That built-in calibration file results in measurements in cm. The file you created by running KinectUtil getCalib results in measurements in mm, therefore all the measured numbers are 10 times larger. This was an oversight in the current Kinect package; I should have added code to make sure that calibration is always in the same units.

    The built-in default intrinsic calibration will be mostly OK for using the sandbox, because the projector calibration step will sort out most discrepancies. But the built-in calibration won’t properly align the depth and color cameras (the latter isn’t used for the sandbox), which is probably what you’re seeing in KinectViewer.

    For simplicity, go with the built-in default calibration right now, because otherwise you’d have to change a few numbers throughout other sandbox configuration files to account for the 10-times size difference.

    Once your sandbox works, you can go back and improve it by doing a full calibration including per-pixel depth correction.

Viewing 15 posts - 466 through 480 (of 522 total)