Vive tracker not working with motion controller in 4.25.3

Hi, I’ve been trying to set up vive tracker for use in unreal 4.25.3 projects (to move virtual camera), and just having no luck getting any movement/position data from the tracker. I’m using a motion contoller in a blueprint set as ‘Special_1’ source - and I’ve done the whole vive bindings thing by selecting my ‘vive tracker on camera’ and editing action poses to enable ‘Special_1’ as raw data pose for the unreal project I am editing. There is a dummy axis mapping enabled in the project, Steam VR is running… everything is powered up. When running the scene I have a debug print string in the blueprint to grab/print the transform of the motion controller… but not seeing any data (other than the default position data (all 0s for xyz etc)). Pulling my hair out all day/week on this one… watched all the youtube videos on tracker binding etc… Any suggestions??? thanks. (note - using vive cosmos)

Did you figure this out? I’m in the exact same situation, can’t get the tracker to work…

Hi, not sure if this solves your problem, but at our studio, after updating to 4.26 we were not being able to get any data from “Special_1”. After trying other alternatives, we were able to get it by changing the Motion Source to “Tracker_Camera”.

Hope it helps!


Were you able to solve this? I’m having the same issue.

In UE 4.25+, the binding step appears to no longer works for the Trackers which in affect eliminates all the “Special” input sources. For Input Source in UE, choose one of the sources that start with “Tracker_”. This should match the roles you can chose for the Tracker in SteamVR. Then, in the SteamVR settings, select the Tracker role that matches the Input Source you selected in UE.

This is not documented anywhere in HTC or in Epic Games so it would be cool if they did that.