# Calibraation files not saving and camera intrinsics failing

Source: https://forum.modalai.com/topic/4682/calibraation-files-not-saving-and-camera-intrinsics-failing
Category: Autonomy: VIO, Mapping and Navigation (https://forum.modalai.com/category/19/autonomy-vio-mapping-and-navigation)
Tags: vio
Posted: 2025-08-15 16:00:35 UTC by Idan Fiksel
Replies: 4 · Views: 3416

## Idan Fiksel · 2025-08-15 16:00:35 UTC

Hi everyone,

Im using the Starling V2 board on a VOXL2 which is integrated on a custom drone. Currently I'm trying to set up VIO on the drone. I configured the camera extrinsics, calibrated the IMU. I went through the process of calibrating the gyro, accel, mag, baro, and level horizon on px4 through QGC. When I check for the files they are not saved:
voxl2 (M0054):~$ voxl-check-calibration
Calibration File Status:
Present /data/modalai/voxl-imu-server.cal 
Present /data/px4/param/parameters_gyro.cal 
Missing /data/px4/param/parameters_acc.cal 
Missing /data/px4/param/parameters_level.cal 
Missing /data/px4/param/parameters_baro_tc.cal 
Missing /data/px4/param/parameters_mag.cal 

Detected Missing Calibration Files
please run the required cals
https://docs.modalai.com/calibration/

when I try to run qVIO server it failes because it is missing the opencv_tracking_front_intrinsics.yml. I've bee going throught the process of calibrating the tracking cameras with the 9x6 checker boards but its constantly failing. it says it most likely due to motion blur. the tracking cam im using is the AR0144 forward and down.

I've been running this line "sudo voxl-calibrate-camera tracking_front -s 9x6 0.023". I tried it also with fisheye but that didn't work as well. 

Can someone provide a possible reasoning for this or share some tips to complete these steps?
@QSL

## Reply by Moderator (ModalAI staff) · 2025-08-15 22:53:32 UTC

@Idan-Fiksel Is the calibration card mounted to a hard backing piece so there are no warps or wrinkles in the checkerboard? 

Did you print with a PDF so that the checkerboard measurements are accurate?

## Reply by Idan Fiksel · 2025-08-18 17:06:10 UTC (in reply to Moderator)

@Moderator The checker board was glued to cardboard as a backing. I printed the 9x6 as a PDF. The size of the squares are ~23mm is the the correct size?

## Reply by QSL · 2025-08-19 19:42:17 UTC (in reply to Moderator)

@Moderator any additional assistance?  What would cause these calibration files to fail to save?  

Thanks!

## Reply by Manoj Kashyap · 2025-08-20 03:27:12 UTC (in reply to Moderator)

@Moderator Even I am facing the same issue. Did everything as per the instructions on the official website. But unable to calibrate the stereo front. I was able to calibrate stereo back though. I have attached the error along for your reference.