Jump to content
Happy Holidays! Limited Staff Responses: 1/20 - 1/31 ×

HTC Vive Tracker drone tracking loss


BosM
 Share

Recommended Posts

I am working on a setup with a Parrot Bebop 2 drone to track its pose while flying.

My setup works fine when manually moving around the tracker, but once the drones motors switch on, I read out (at the same frequency) 0.0 on all 6 axes (using pyopenvr).

 

According to what I read on similar posts, this is due to the IMU that can't deal with high-frequency vibrations.

The suggested solution is mechanical damping.

Now the Parrot Bebop 2 already has mechanical damping between the main body and the X-frame on which the motors are attached, but still I face the tracking loss problem.

 

I also read that Developer guidelines v1.5 describes Tracker Firmware where a low pass filter is included.

I was wondering if there is a way to 'downgrade' my current Tracker FW version to v1.5, such that, hopefully, the combination of the LPF and the mechanical damping from the drone will result in successful tracking.

Or maybe even ignore the IMU readings, since in the drone an IMU is present and I can do the sensor fusion with only the infrared information from the Vive Tracker.

Link to comment
Share on other sites

, the current firmware for gen 1 trackers (grey logo) is the on covered by the 1.5 guidelines; if you're using the most recent firmware on those trackers, those functions still work as covered in the guidelines. If you're using Tracker 18' (blue logo) than it's a different story as there are both hardware firmware differences that have led to a loss of the LPS functions. To be honest, software based LPS simply wasn't very effective in dealing with the types of use cases that people were getting stuck with - it is a factor in why we've moved towards recommending mechanical dampening. 

 

SteamVR pose correction is pretty dependent on IMU data. You can't simply ignore it unfortunately without throwing the entire default system out. Some developers have come up with custom SteamVR pose solvers that exclude IMU data such as this example from NASA - custom solutions are quite impractical for most users. You can see in their readme it does reduce accuracy quite a bit. 

 

In some cases, you're better off using visual tracking - this is really pushing the use case of Vive Tracker. 

Link to comment
Share on other sites

Thank you for your reply.

We have followed your advice and designed mounts with damping elements.

In a first version we put the tracker on top, but there we still got the reading out 0.0 problem, so we adapted the design and mounted the tracker on the back as can be seen on the pictures below.

This seems to work (for now). The balance of the drone is now a bit disturbed, but the flight controller seems to manage it quite well, and we're also testing with small weights on the nose to counteract the weight on the back, which improves stability a bit.

 

 

 

Link to comment
Share on other sites

  • 4 weeks later...

Hi,

 

After some more extensive testing, we notice that the current solution of mechanical damping is not robust. Most of the time we read out proper values, but often we lose the measurements again. In autonomous flight it is vital that this does not occur.

 

But it feels like we're close. We would like to try to combine our current solution with the LPF on the grey tracker. But apparently it's not something you can permanently turn on. On our drone we are not able to repeatedly turn on the LPF.

 

Is it possible to provide us with firmware where the LPF is permanently present?

 

Kind regards

 

Link to comment
Share on other sites

  • 4 weeks later...

Hi everyone,

 

I too have been trying to get an htc vive tracker to work attached to a flying drone, but am facing the same problem. Even with mechanical damping the measurements still fail sometimes.

 

I too am wondering whether a version of the firmware for the v1 tracker is available in which the low pass filter is permanently enabled, or if a version of this software could be made available?

 

Thanks in advance!

Kind regarda

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...