Skip to content
  • Categories
  • Recent
  • Tags
  • Popular
  • Users
  • Groups
Collapse
Brand Logo

ModalAI Forum

  1. ModalAI Support Forum
  2. VOXL Dev Kits
  3. VOXL Flight Deck
  4. VOA outputting zeros as distances

VOA outputting zeros as distances

Scheduled Pinned Locked Moved VOXL Flight Deck
voastereo camerasdfs disparityvoxl-vision-px4
11 Posts 4 Posters 2.8k Views 1 Watching
  • Oldest to Newest
  • Newest to Oldest
  • Most Votes
Reply
  • Reply as topic
Log in to reply
This topic has been deleted. Only users with topic management privileges can see it.
  • Chad SweetC Offline
    Chad SweetC Offline
    Chad Sweet
    ModalAI Team
    wrote on last edited by
    #2

    Can you please log and share some data using voxl-logger?

    The command to log stereo and disparity is:

    voxl-logger --cam stereo --cam dfs_disparity
    

    That would help diagnose the issue

    U 1 Reply Last reply
    0
    • ? Offline
      ? Offline
      A Former User
      wrote on last edited by
      #3
      This post is deleted!
      1 Reply Last reply
      0
      • Chad SweetC Chad Sweet

        Can you please log and share some data using voxl-logger?

        The command to log stereo and disparity is:

        voxl-logger --cam stereo --cam dfs_disparity
        

        That would help diagnose the issue

        U Offline
        U Offline
        Uros
        wrote on last edited by
        #4

        @Chad-Sweet
        Hello Chad and sorry for the delayed response. We uploaded the outputs of the logger. They can be found on this link. We tried the same stereo camera pair on two different boards and we still have the same problem.

        1 Reply Last reply
        0
        • Chad SweetC Offline
          Chad SweetC Offline
          Chad Sweet
          ModalAI Team
          wrote on last edited by
          #5

          At a quick glance, the left and right image do not look co-planar and aligned vertically. It's a little tough to tell though as maybe your UAV is slanted? I would expect the left and right images to just look like subtle shifts directly left or right from each other.

          U 1 Reply Last reply
          0
          • Chad SweetC Chad Sweet

            At a quick glance, the left and right image do not look co-planar and aligned vertically. It's a little tough to tell though as maybe your UAV is slanted? I would expect the left and right images to just look like subtle shifts directly left or right from each other.

            U Offline
            U Offline
            Uros
            wrote on last edited by
            #6

            @Chad-Sweet
            Yes, we noticed that as well, but this is the way the cameras are mounted on the flight deck so we thought the difference is small enough. The uploaded data is from a voxl flight deck with stereo cameras that were not touched, not from the setup where we replaced one of the cameras, sorry for the confusion. Can you recommend a way to level the cameras inside the flight deck or can this misalignment somehow be fixed through calibration maybe?

            1 Reply Last reply
            0
            • Chad SweetC Offline
              Chad SweetC Offline
              Chad Sweet
              ModalAI Team
              wrote on last edited by
              #7

              OK, the flight deck should be fine as they are all calibrated and tested prior to shipping.

              Have you tried recalibrating in case the image sensors were jostled in some way?

              There is a good video tutorial here: https://docs.modalai.com/calibrate-cameras/#stereo-calibration-process

              1 Reply Last reply
              0
              • Dobry KolaczD Offline
                Dobry KolaczD Offline
                Dobry Kolacz
                ModalAI Team
                wrote on last edited by
                #8

                Would you mind sending a photo of what your flight deck front plate looks like? I would like to see how the stereo cameras look/are mounted. The differences between your right and left stereo cameras seem a bit uncharacteristic for a VOXL flight deck (which is weird because you are saying those photos are coming from your setup before you replaced the stereo camera).

                The other thing I noticed in the photos you provided was that the right stereo camera was slightly less in focus than the left stereo camera. I have the most success calibrating cameras when their focus is more closely matched. I look at the center of the image to gauge focal clarity as there are some stereo cameras that have some slight blurring at the edges of the image which can be misleading when adjusting focus.

                1 Reply Last reply
                0
                • U Offline
                  U Offline
                  Uros
                  wrote on last edited by
                  #9

                  @Chad-Sweet Yes, we calibrated right before we ran the voxl-logger to get the data. We followed those instructions and the calibration was a success.
                  @Dobry-Kolacz Here are the photos of the front plate. We also tried to focus based on the center of the image, since there was always some blur towards the edges. Is it not focused enough?
                  voxl_front_plate1.jpg
                  voxl_front_plate2.jpg

                  1 Reply Last reply
                  0
                  • Dobry KolaczD Offline
                    Dobry KolaczD Offline
                    Dobry Kolacz
                    ModalAI Team
                    wrote on last edited by
                    #10

                    My apologies for the delay in response,
                    So just to be clear, the images you provided are from the setup where VOA was working? The offset is odd, but the flight decks are calibrated and ready to go before they ship out so I'm wondering if that setup had any issues before the stereo camera was replaced.
                    The flight deck doesn't have any obvious defects from the photos you provided (the mounting screws seem to be tight, the front plate seems to be straight, and from what I can tell the stereo cameras are fully secured.
                    Judging on your photos, I would say that the right camera could definitely be a bit more in focus (the left camera seems to be perfectly in focus). It's easiest to tell based on your voxl1-log images.
                    Though I don't think this is necessarily contributing to your issues, it is worth mentioning that sometimes the lenses benefit from being cleaned with a clean q-tip or a microfiber cloth.

                    1 Reply Last reply
                    0
                    • Dobry KolaczD Offline
                      Dobry KolaczD Offline
                      Dobry Kolacz
                      ModalAI Team
                      wrote on last edited by
                      #11

                      @Uros
                      .
                      .

                      1 Reply Last reply
                      0

                      Hello! It looks like you're interested in this conversation, but you don't have an account yet.

                      Getting fed up of having to scroll through the same posts each visit? When you register for an account, you'll always come back to exactly where you were before, and choose to be notified of new replies (either via email, or push notification). You'll also be able to save bookmarks and upvote posts to show your appreciation to other community members.

                      With your input, this post could be even better 💗

                      Register Login
                      Reply
                      • Reply as topic
                      Log in to reply
                      • Oldest to Newest
                      • Newest to Oldest
                      • Most Votes


                      ModalAI
                      Categories Recent Tags ModalAI.com Docs
                      © 2026 ModalAI® · Accelerating autonomy for smaller, smarter, safer drones · Powered by NodeBB
                      • Login

                      • Login or register to search.
                      • First post
                        Last post
                      0
                      • Categories
                      • Recent
                      • Tags
                      • Popular
                      • Users
                      • Groups