m500 cannot hovering with VIO algorithm

Kaiba-Kun · 27 Feb 2021, 17:53

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.

Chad Sweet · 27 Feb 2021, 17:56

A couple of ideas:

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

Kaiba-Kun · 27 Feb 2021, 18:09

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

Kaiba-Kun · 27 Feb 2021, 18:14

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

Chad Sweet · 27 Feb 2021, 19:45

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?

Kaiba-Kun · 28 Feb 2021, 08:33

Hi @Chad-Sweet here is the serial number.

Chad Sweet · 28 Feb 2021, 22:16

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>

Kaiba-Kun · 1 Mar 2021, 03:53

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.

For the camera matrix i've checked in the ~/.ros/root/camera_info folder and they also non change

Chad Sweet · 1 Mar 2021, 04:03

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

Kaiba-Kun · 2 Mar 2021, 02:35

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.