Effect of onboard computer and antennas on compass and orientation

Hardware ZED2
1

I am holding an onboard computer and WiFi antennas behind the ZED 2 camera. there is a realized continuous drafting in orientation (just in Y axis (in image frame)) could it be because of the effect of other components on the compass or it’s a software (configurations). If it because of external effect there is a recommendation I should follow ?

2

Hi @KH_CV
the magnetometer sensor is not currently used in sensor fusion for the positional tracking module, to magnetic fields should not affect the results of the pose estimated by the ZED SDK.
If you are using the magnetometer for your own sensors fusion algorithm you should calibrate the sensor by using the ZED_Sensors_Viewer application keeping the camera in the same configuration of when it’s used for the positional tracking.

3

Hi there,
This seemed to be the bedt thread for a short followup question.

I have GPS antennas that have magnets inside (for placing on a magnetic ground plane). Do you think that the there will be any interference with the IMU, either because the IMU uses magnetometer data for stabilization or through some other physical reason?

There will be interference with the magnetometer almost definitely I assume, right?

Thanks!

4

Hi @Ben93kie
Welcome to the Stereolabs community.

The ZED positional tracking module does not use magnetometer information, so the presence of magnet does not affect the performance.
If you plan to use the magnetometer (you can replace the yaw with the real compass reading) you can calibrate it in the final configuration to compensate for the effects of the magnets.

5

From a different account (have two Github accounts, sorry!)
Thanks for the prompt reply!
Just to be 100% sure, if I call something like

sensors_data.get_imu_data().get_pose().get_orientation()

it won’t use the magnetometer? In other words, what entails the positional tracking module?

And by calibration/compensation, you mean the calibration procedure mentioned here?

Thanks!

6

The orientation of the camera is always referred to as the starting orientation when the Positional Tracking module is enabled.

Yes, exactly

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