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  4. m500 cannot hovering with VIO algorithm

m500 cannot hovering with VIO algorithm

Scheduled Pinned Locked Moved VOXL m500 Reference Drone
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  • Kaiba-KunK Offline
    Kaiba-KunK Offline
    Kaiba-Kun
    Contributor
    wrote on last edited by
    #9

    Also,

    • We never try to flight in the manual mode, only use the position and offboard mode.
    • I don't think the external material was the reason for this issue because we had attached the component in the bottom of the frame closed as much as possible.
      Thank you.
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    • Chad SweetC Offline
      Chad SweetC Offline
      Chad Sweet
      ModalAI Team
      wrote on last edited by
      #10

      A couple of ideas:

      1. Try to calibrate the tracking camera. Instructions here: https://docs.modalai.com/calibrate-cameras/#calibrate-tracking-camera
      2. Insert some foam, preferably memory foam, in between the "green tray" and the frame. This should help reduce vibration

      PXL_20201203_025334070.jpg
      PXL_20201203_025319045.jpg

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      • Kaiba-KunK Offline
        Kaiba-KunK Offline
        Kaiba-Kun
        Contributor
        wrote on last edited by
        #11

        Thank for reply,
        I'll try it in the tomorrow. We're in middle of night (GMT +7).

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        • Kaiba-KunK Offline
          Kaiba-KunK Offline
          Kaiba-Kun
          Contributor
          wrote on last edited by
          #12

          if you have more advices, please tell us.
          Best regard.

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          • Chad SweetC Offline
            Chad SweetC Offline
            Chad Sweet
            ModalAI Team
            wrote on last edited by
            #13

            Can you please send the serial number of the VOXL Flight PCB? We might be able to look up the calibration files in our production database?

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            • Kaiba-KunK Offline
              Kaiba-KunK Offline
              Kaiba-Kun
              Contributor
              wrote on last edited by Kaiba-Kun
              #14

              Hi @Chad-Sweet here is the serial number.
              154955241_364816714780053_1252967837988134452_n.jpg

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              • Chad SweetC Offline
                Chad SweetC Offline
                Chad Sweet
                ModalAI Team
                wrote on last edited by Chad Sweet
                #15

                Here's the test data:

                Stereo Camera Calibration

                left_file:
                image_width: 640 image_height: 480 camera_name: stereo/left camera_matrix: rows: 3 cols: 3 data: [492.469682, 0.000000, 287.720563, 0.000000, 492.799801, 241.856917, 0.000000, 0.000000, 1.000000] distortion_model: plumb_bob distortion_coefficients: rows: 1 cols: 5 data: [-0.171887, 0.054112, 0.000816, 0.000653, 0.000000] rectification_matrix: rows: 3 cols: 3 data: [0.999125, 0.024029, 0.034224, -0.023993, 0.999711, -0.001454, -0.034249, 0.000631, 0.999413] projection_matrix: rows: 3 cols: 4 data: [509.343373, 0.000000, 291.779423, 0.000000, 0.000000, 509.343373, 233.497673, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000]

                right_file:
                image_width: 640 image_height: 480 camera_name: stereo/right camera_matrix: rows: 3 cols: 3 data: [494.055474, 0.000000, 337.960482, 0.000000, 494.170184, 223.591690, 0.000000, 0.000000, 1.000000] distortion_model: plumb_bob distortion_coefficients: rows: 1 cols: 5 data: [-0.182939, 0.076209, 0.000049, 0.002344, 0.000000] rectification_matrix: rows: 3 cols: 3 data: [0.999497, 0.010498, 0.029940, -0.010529, 0.999944, 0.000885, -0.029929, -0.001200, 0.999551] projection_matrix: rows: 3 cols: 4 data: [509.343373, 0.000000, 291.779423, -40.695510, 0.000000, 509.343373, 233.497673, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000]

                snav_file:
                <SnavCalibration> <SnavCalibrationStereo> <SnavCalibrationLeftStereo> <param name="calib_pixel_width" value="640" /> <param name="calib_pixel_height" value="480" /> <param name="calib_memory_stride" value="640" /> <param name="principal_point_x" value="287.720563" /> <param name="principal_point_y" value="241.856917" /> <param name="focal_length_x" value="492.469682" /> <param name="focal_length_y" value="492.799801" /> <param name="distortion_0" value="-0.171887" /> <param name="distortion_1" value="0.054112" /> <param name="distortion_2" value="0.000816" /> <param name="distortion_3" value="0.000653" /> <param name="distortion_4" value="0.0" /> <param name="distortion_5" value="0.0" /> <param name="distortion_6" value="0.0" /> <param name="distortion_7" value="0.0" /> <param name="distortion_model" value="4" /> </SnavCalibrationLeftStereo> <SnavCalibrationRightStereo> <param name="calib_pixel_width" value="640" /> <param name="calib_pixel_height" value="480" /> <param name="calib_memory_stride" value="640" /> <param name="principal_point_x" value="337.960482" /> <param name="principal_point_y" value="223.59169" /> <param name="focal_length_x" value="494.055474" /> <param name="focal_length_y" value="494.170184" /> <param name="distortion_0" value="-0.182939" /> <param name="distortion_1" value="0.076209" /> <param name="distortion_2" value="0.000049" /> <param name="distortion_3" value="0.002344" /> <param name="distortion_4" value="0.0" /> <param name="distortion_5" value="0.0" /> <param name="distortion_6" value="0.0" /> <param name="distortion_7" value="0.0" /> <param name="distortion_model" value="4" /> </SnavCalibrationRightStereo> <param name="correction_factors_0" value="0" /> <param name="correction_factors_1" value="0" /> <param name="correction_factors_2" value="0" /> <param name="correction_factors_3" value="0" /> <param name="translation_0" value="-0.0798577979308862" /> <param name="translation_1" value="-0.000838769063517393" /> <param name="translation_2" value="-0.00239214571934757" /> <param name="rotation_0" value="0.00226741960521865" /> <param name="rotation_1" value="0.00433160780762917" /> <param name="rotation_2" value="-0.0134848065488883" /> </SnavCalibrationStereo> </SnavCalibration>

                Tracking Camera Calibration

                cal_file:
                image_width: 640 image_height: 480 camera_name: tracking camera_matrix: rows: 3 cols: 3 data: [277.095893, 0.000000, 324.145728, 0.000000, 277.407080, 209.238122, 0.000000, 0.000000, 1.000000] distortion_model: fisheye distortion_coefficients: rows: 1 cols: 4 data: [-0.018687, 0.034754, -0.034056, 0.011701] rectification_matrix: rows: 3 cols: 3 data: [1.000000, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000, 0.000000, 0.000000, 1.000000] projection_matrix: rows: 3 cols: 4 data: [303.434082, 0.000000, 333.786106, 0.000000, 0.000000, 297.322021, 188.396771, 0.000000, 0.000000, 0.000000, 1.000000, 0.000000]

                snav_file:
                <SnavCalibration> <SnavCalibrationDownward> <param name="calib_pixel_width" value="640" /> <param name="calib_pixel_height" value="480" /> <param name="calib_memory_stride" value="640" /> <param name="principal_point_x" value="324.145728" /> <param name="principal_point_y" value="209.238122" /> <param name="focal_length_x" value="277.095893" /> <param name="focal_length_y" value="277.40708" /> <param name="distortion_0" value="-0.018687" /> <param name="distortion_1" value="0.034754" /> <param name="distortion_2" value="-0.034056" /> <param name="distortion_3" value="0.011701" /> <param name="distortion_4" value="0" /> <param name="distortion_5" value="0" /> <param name="distortion_6" value="0" /> <param name="distortion_7" value="0" /> <param name="distortion_model" value="10" /> </SnavCalibrationDownward> </SnavCalibration>

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                • Kaiba-KunK Offline
                  Kaiba-KunK Offline
                  Kaiba-Kun
                  Contributor
                  wrote on last edited by
                  #16

                  Thank for answer, I've checked the test data above. Here is the list of the /etc/snav# diectory and i checked the calibration.downward.xml and calibration.stereo.xml but both of them are similar as the test data from you.
                  b54efdf2-0f05-4f51-b261-59adffce1c7d-image.png

                  • For the camera matrix i've checked in the ~/.ros/root/camera_info folder and they also non change
                    74e2739b-5575-4cbe-9c9d-eb13758784a9-image.png
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                  • Chad SweetC Offline
                    Chad SweetC Offline
                    Chad Sweet
                    ModalAI Team
                    wrote on last edited by
                    #17

                    Ok, they should be exact. Did you remove vibration by adding foam?

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                    • Kaiba-KunK Offline
                      Kaiba-KunK Offline
                      Kaiba-Kun
                      Contributor
                      wrote on last edited by
                      #18

                      Yes, after adding some foam, The UAV now are stable than a bit. Do you think the battery should be problem? Our 3S battery are quite old.

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