VOXL2 Camera Calibration fails and bad QVIO tracking
-
Drone specification:
I am currently using Starling 2 Max with
- Dual 4k & Dual Tracking & ToF (C29)
- Microhard pMDDL2450 WiFi
- Ghost Atto 2.4GHz
- SKU: MRB-D0012-4-V2-C29-M11-T9-K3 (NOTE: This SKU is from the order receipt, which is different from the one shown when connected to the drone)
system-image: 1.8.06-M0054-14.1a-perf kernel: #1 SMP PREEMPT Wed Oct 22 04:13:18 UTC 2025 4.19.125 hw platform: M0054 mach.var: 1.0.1 SKU: MRB-D0012-4-V2-C29-T9-M22-X0 voxl-suite: 1.6.3Cause:
I recently flashed my VOXL2 board by following "Unbricking your VOXL2" page. This wipes all calibration files, of which I generated new ones by calibrating the drone again.
However, I am having issue getting a successful camera calibration with the same error every time:
Re-projection error reported by calibrateCamera: 1.26416 Calibration Failed Max reprojection error: 0.60 This is most likely due to motion blur, please try again. Exiting CleanlyI have tried to debug by following these suggestions below:
https://forum.modalai.com/post/22010
https://forum.modalai.com/post/22066
https://forum.modalai.com/post/21909
However, none of these fixes the max reprojection error.Finally, I manually write the files:
- /data/modalai/opencv_tracking_front_intrinsics.yml
- /data/modalai/opencv_tracking_down_intrinsics.yml
by using the camera matrix from the trial with smallest reprojection error (close to ~0.6).
Current Issue:
My problem now is that, since the calibration files use bad camera matrices, the qvio tracking of the drone is inaccurate and drifts a lot. Here, I tested the front and downward camera by walking around in circle and returning the drone to the exact starting position. The result shows a lot of drift in both qvio_extended and ov_extended

My questions are:
- Could the reflash have altered camera driver versions, exposure/gain settings, or
voxl-camera-serverconfig from factory defaults? - Is there a way to compare my current per-camera intrinsics files against known-good factory defaults for the M0054 platform?
- Are there other config I should try to change to aid the camera calibration process?
- Is there any other open-source code that allows me to manually calibrate the camera?
Thank you for your time and help!
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