Sean Robinson

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Viewing 15 posts - 106 through 120 (of 173 total)
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  • in reply to: Reassigning camera height #2355
    Sean Robinson
    Participant

    The only way I know to safely change the camera-sand distance is by recalibrating the camera and camera-projector. Repeat Steps 8 throug 11 of the installation instructions.

    If nothing is changed, check thet you are editing the files the sandbox is using.

    in reply to: Segmentation fault (core dumped). SandBox doesen’t work #2354
    Sean Robinson
    Participant

    “Segmentation fault” is a general error that means there was a problem reading or writing in memory.

    The two ways I can imagine to fix this:

    1) Remove and rebuild Vrui, Kinect, and SARndox. There may have been a minor problem during the build and restarting from a clean state may help.

    2) Look at the core dump for information about what to check.
    See my post for hints about reading the core dump.

    in reply to: Projection mostly black #2353
    Sean Robinson
    Participant

    Can you share photos of the post-calibration projection?

    in reply to: Quick check on graphics card suitability #2352
    Sean Robinson
    Participant

    The specs look good for the water simulation.

    in reply to: Regarding the choice of sand #2342
    Sean Robinson
    Participant

    Sounds like you have a good experiment. Buy a small amount of sand and project onto it.

    During my early prototype, I used the 35lbs or so of tan/gray sand we had in stock and it looked fine. As long as your projector is bright, I would expect any light tone sand to work.

    I did end up buying the Sandtastik White sand. Out district’s office supply vendor happened to sell Sandtastik sand and that saved me the price of shipping 200lbs of sand.

    in reply to: No se pudo localizar el paquete libdc1394-22-dev #2340
    Sean Robinson
    Participant

    Are you using Linux Mint 19.3? The error makes me think you are using a more recent version. Use the recommended version if you can.

    in reply to: No rain with hand #2339
    Sean Robinson
    Participant

    See this previous post for ideas. Let us kow if that does not help.

    Sean Robinson
    Participant

    I’ve not done more than play with different liquid textures, so others might have better information.

    The key piece is replacing the SurfaceAddWaterColor.fs file with a copy using different colors. Search inside that file for “Lava” for the line to change. The sandbox will automatically update if you replace SurfaceAddWaterColor.fs while SARndbox is running.

    in reply to: Regarding the choice of sand #2337
    Sean Robinson
    Participant

    Any sand is usable. All varieties will have benfits and drawbacks.

    Have you seen the “Sand” and “Health Concerns” sections of the online instructions?

    in reply to: non “short-throw” projectors #2334
    Sean Robinson
    Participant

    I think the Promethean has too short of a throw. As I read the specs, it will not focus beyond a 24 inch throw distance. It’s common to have around a 40 inch throw distance on a sandbox. Focus is not generally vital with the projected sandbox content (except for calibration), but this may be too far out.

    in reply to: Kinect depth camera #2333
    Sean Robinson
    Participant

    From the image you shared, I suspect your depth camera has died. Are there any error messages in the terminal window where you started RawKinectViewer?

    in reply to: Vrui VR Toolkit Installation Linker Error #2332
    Sean Robinson
    Participant

    The only thing I have seen similar to this is when I have tried to continue on from a failed build. The Make dependency graph does not see the need to recompile object files, so stale files are used during linking. One option is to remove the src directory before re-running bash Build-Ubuntu.sh.

    Sean Robinson
    Participant

    Do you have sand? Or are you still using cardboard?

    I suspect the calibration error message is because all your tie points are above the “sand”. Once you are able to capture tie points below the sand surface level, I expect the error messages will stop.

    Look for the “calibration-error-some-tie-points-have-negative-projection-weights” topic on the old forum on the Wayback Machine for a hint from okreylos about tie points.

    (I would show the direct link, but my post fails when I include it.)

    Sean Robinson
    Participant

    Thank you for sharing the videos. That makes it much faster to see possible causes.

    I believe the source of your calibration problems is that the handle on your target is too wide. The calibration software needs to “see” a circle floating in space and will not project green if fingers, box walls, sand, or other things are too close. Assuming the circle has a 12 cm diameter (CD size), your handle is about 1.6 cm across where it intersects the circle. Try replacing your wide handle with a stiff wire and keep at least a 5 cm gap between the circle and your fingers.

    Let me know if this works or not.

    in reply to: Sandbox Base Plane Equation #2308
    Sean Robinson
    Participant

    I’ve seen this when I forget to “Average Frames” before trying to extract the base plane. Read the second paragraph of Step 8 again and let me know if this does not solve your issue.

Viewing 15 posts - 106 through 120 (of 173 total)