Mapping Status in ZED Positional Tracking

Hello,

I have been experimenting with the ZED Positional Tracking module and its area memory feature. And although the step to export the map is quite clear, I am interested in knowing when the mapping is done sufficiently. That is, how do I know that the map I am about to export is sufficiently mature or I need to do more mapping? Is there also a way to incrementally build upon previous maps by loading them, doing positional tracking and exporting?

Also, just curious - in the class sl::Pose, there are twist attributes which never seem to be populated with values and always return 0s - is there some catch in order to activate them? I am able to get Pose readings just fine.

Hi Sir,
Please be patient.
We handle numerous support requests daily and typically respond within 24 working hours.

Best regards

Walter

Walter Lucetti
Senior Computer Engineer
SDK / Robotics / HW
Stereolabs Support

Hi @ya_in_ca
Welcome to the Stereolabs community.

It’s not possible to obtain this information. The ZED SDK cannot be aware of the exact dimensions and complexity of an environment. It’s up to you to know when you have completely explored the environment.

When you start a new instance of the Positional Tracking module, loading an existing area memory file, the SDK internally updates it with new information. If you save it before stopping the processing, you will receive an updated file with any new information available.
For this reason, it’s also important to navigate an area with different light conditions to obtain a reliable area memory database.

Velocity is available only by using specific algorithms. What mode are you using?

I am using Positional Tracking (IMU Fusion, GEN_3, NEURAL_LIGHT, AreaMemory) - I tried in both reference frames WORLD and CAMERA to no avail.

Speed estimation will be added in a future version of the ZED SDK for GEN_3

Thank you for your responses!

One followup - can we check what features the ZED is looking at in the scene?

Yes, you can use the getPositionalTrackingLandmarks and getPositionalTrackingLandmarks2D API functions

Cool, thanks for pointing that out.

Is it possible to use the area file map generated from one camera with a different camera of same model?

No, this is not supported

Even if they use same configs (fps, resolution depth mode etc.)?

I am generating an .area map file using one ZEDx mini, and was wondering about exporting to other ZEDx minis

Yes, in any case.

This is not supported.

Currently, each area map file can be used only with the same camera used to generate it.

We are working on an upgrade to make the area map file shareable between different cameras.