VOXL VIO frame rate change

yu zhang

Hi @Alex-Gardner ,

I use voxl-inspect-cam to check the outputs of the VIO.
Screen Shot 2022-02-17 at 2.33.23 PM.png

It shows the default frame rate of VIO is 30FPS. I am wondering how could I simply change different frame rates (e.g., 60/90FPS)? Also, where could I locate the VIO code if I would have a look at the usage of frame rate?
I double-check that the tracking camera could be set up to 120FPS, and the VIO on voxl could be set up to 90FPS. So, I am wondering what if changing to 120FPS manually could cause any memory or CPU load issues?
Referring to one of my previous posts about VIO path estimation in figure 1. I am wondering if the VIO will continue to work all time even when switching to GPS mode? In figure 1, it seems the red line is made by VIO, and it (especially for figure 8 estimation) looks much more smooth than the GPS blue line. I am also wondering how about battery consumption of VIO if it's enabled for all-time use? What if changing to a high frame rate, will it cause more battery drain?

yu zhang

Hi @Alex-Gardner ,
I am following up on this question. Please any thoughts about it? Thanks.

There shouldn't be anything stopping you from running VIO at 120hz, the source for qvio server can be found here. Note that we've tested VIO at higher framerates and didn't see a significant inprovement to performance.

VIO is a service that runs on voxl, you can enable or disable it on board, but it's the px4 parameters which tell the flight controller whether or not to use the data.

In regards to the battery, any power consumed by running software on the voxl will be truly miniscule compared the the amount required to run motors on an airframe.

yu zhang

@Alex-Gardner Thanks so much, and I will have a look at it then

yu zhang

@Alex-Gardner I also posted another one about an instruction issue of installing voxl-cross locally here:
https://forum.modalai.com/topic/755/voxl-cross-installation-document-missing

Please feel free to double-check if this is an issue.
Thanks again.

yu zhang

Hi @Alex-Gardner , a quick question about building.

Should I use dev or stable version for building my version code like building voxl-vision-px4 or voxl-qvio-server with my modification?

Generally you should be using stable unless you're planning to use a specific new feature that has been added to the dev branch. I'm not even sure if there have been any changes to our support libraries since the last release, most of what we've been doing has been on our leaf node packages that stand alone to provide a function.

yu zhang

@Alex-Gardner all right, thanks for that