Calibration Issues

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  • #2113
    John M.
    Participant

    I’m attempting to calibrate my AR Sandbox following this tutorial, and I’m having some issues. I made the disk needed out of a paper plate, and attaching a wire to it, but when I attempt to use it to calibrate, the circle stays yellow and does not appear green. In other words, it won’t let me calibrate with it. I’m new to Linux, so I have no idea if this is an issue with the circle I made or an issue with software. Does the circle need to be a specific size for it to work, or something like that?

    • This topic was modified 2 years ago by John M.. Reason: Accidentally hit enter before I finished typing
    #2116
    Sean Robinson
    Participant

    The target disk does need to be close to CD/DVD size (12 cm diameter) before the DiskExtractor will mark it as a valid target. If I’m reading the code right, any diameter between 10.9 cm and 13.2 cm should work.

    #2156
    Dvd_frodo
    Participant

    Hello guys. I need some guidance. We are setting up our Sandbox here in Curitiba – Brazil.
    We’re having trouble calibrating Kinect. When we ask it to calibrate and we make the selection by pressing button 1, when finished the depth value generates -nan. In the video we see that the value is filled.
    Another problem is in the calibration of the projector. When pressing the 1 key or spacebar and selecting capture, the warning window appears, but when pressing the 1 key or any other key nothing happens and the marker does not change its position. Someone could help us. Thanks

    #2157
    Dvd_frodo
    Participant

    Hello guys. I need some guidance. We are setting up our Sandbox here in Curitiba – Brazil.
    We’re having trouble calibrating Kinect. When we ask it to calibrate and we make the selection by pressing button 1, when finished the depth value generates -nan. In the video we see that the value is filled.
    Another problem is in the calibration of the projector. When pressing the 1 key or spacebar and selecting capture, the warning window appears, but when pressing the 1 key or any other key nothing happens and the marker does not change its position. Someone could help us.
    Thanks

    #2158
    Sean Robinson
    Participant

    I have a few questions to better understand what to are doing and seeing.

    I’ll assume you are “calibrating Kinect” with RawKinectViewer. Which field in the output says “-nan”? Do you have a value for “Camera-space plane equation”?

    I’ll assume you are using CalibrateProjector when the second problem appears. After the “warning window” appears, do you press a second, different key? When you try to capture the first tie point (by centering the target on the crosshairs and pressing “1”), does your terminal window show “Capturing 60 tie point frames…”?

    #2159
    carmemmaluf
    Participant

    Estou com o mesmo problema relatado acima.
    Estou usando o CalibrateProjector. Depois que a “janela de aviso” aparecer, eu pressiono uma segunda tecla diferente. Quando tento capturar o primeiro ponto de amarração -centralizando o alvo na mira e pressionando “1”-, a janela do meu terminal mostra “Capturando 60 quadros de ponto de amarração…”.
    O CD não fica verde e as linhas não mudam de posição.
    Já refiz todos os passos e o final é sempre esse.

    • This reply was modified 1 year, 11 months ago by carmemmaluf.
    #2161
    Sean Robinson
    Participant

    @carmemmaluf,

    If the CD never turns green the tie point capture will not work. It should turn green before you press the “1” key.

    Make sure the CD is isolated from other things (e.g. sand, box wall, a hand). The calibration software looks for a circle.

    #2164
    carmemmaluf
    Participant

    Já coloquei o CD isolado de tudo. P problema é que não fica verde.
    Alguma dica?
    Outra coisa é que a imagem da minha caixa de areia está toda colorida. Não consigo retornar ao fundo azul.

    #2165
    Sean Robinson
    Participant

    Can you link to pictures of your sandbox during calibration?

    For the second part, this is probably related to the Base Plane Equation measured in Step 8. If you change the fourth number (near -100.0) to a few centimeters less negative, it will raise the “sea level”.

    #2166
    Sean Robinson
    Participant

    Alguma dica?

    Random calibration ideas:

    • Use a CD or DVD as the target disc. A too big or too small disc will not work.
    • Add a stiff wire or small stick to hold the target disc.
    • Do not hold the disc itself, hold only the wire or stick. Leave a 2-3 cm gap between your fingers and the target disc edge.
    • Keep the disc at least 2-3 cm from any box or sand wall.
    • Keep the disc at least 2-3 cm above nearby sand.
    • The yellow or green projected circle may not align with the target disc. This is not a problem.
    • When the projected disc is green (no matter where projected), press the capture key.
    • Clean the Kinect lenses with a soft cloth.
    • The Kinect-to-sand distance should be close to 1 meter.

    The list above contains generic advice, pictures from your calibration process might help find something else.

    #2598
    Pseufei
    Participant

    Hello,
    I’m in this step too but I found there’s a yellow frame which restricts the effective view of the 3D camera scanning. But the projector itself projects the image that fit the sandbox. I’m not sure how to enlarge the effective area. Projection calibration
    Thanks

    #2599
    Sean Robinson
    Participant

    Hm, so that yellow frame is supposed to outline the sandbox? After reading the source code for CalibrateProjector.cpp, I see you’re right.

    I suspect the yellow frame does not match the sandbox because your projector (and ours) has a wider aspect ratio than the software originally expected. A 4:3 ratio is hardcoded into CalibrateProjector, while a BenQ MW632ST projects in a 16:10 aspect ratio.

    I’ve never seen the yellow frame match the physical box and it has not been a problem. I recommend ignoring the yellow frame and calibrate as normal.

    #2600
    Pseufei
    Participant

    Hello, thanks for your response.
    I tried to ignore the yellow frame and the sandbox was working properly apart from the map was only limited within the frame. Basically the sand outside of the frame wasn’t covered by the projection image. And that’s what I wanna fix right now. How to make the image fit the whole projection and I use BengQ631st. I’m pretty sure I set 4:3 in the projector and it did project 4:3 image, but only when I run the sandbox the small yellow frame show up and the image became smaller.
    Thanks

    #2601
    Sean Robinson
    Participant

    The BenQ MX631ST looks to have a native 4:3 aspect ratio, so that should be simpler. Otherwise, it appears to be the same as the MW632ST.

    I would try to disable any image processing by the projector. In the projector menus, set the aspect ratio to “Real” and disable digital zoom by setting it to “1.0”.

    #2605
    Pseufei
    Participant

    Hello, I followed your advice and the project still doesn’t fit the whole sand box . Apart from that I found the projection image is quite distorted close to the edge of the image, like the sea is not the lowest, instead it’s on the mountain, but the distortion is much less in the middle of the image.
    I think it’s the calibration problems, so is there any way to check or increase the calibration?
    Thanks

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