Fixing my Valve Index’s extreme tilt

Over the past month or so, my Valve Index has been registering an annoying amount of tilt—when I put it on and start up SteamVR, the floor in VR-land is about five degrees out-of-whack with the actual floor. No amount of room setup re-running or view re-centering would touch the issue. The only fix I could find was to break tracking on the headset by covering it with a towel, then variously aiming the headset straight up or straight down and restoring tracking. Sometimes, this would straighten out the horizon, but often not.

You’d think there’d be an easy way to fix the headset’s tilt, too—like, why isn’t there a SteamVR option to adjust the angle of the horizon? Why is this such a massive issue?

Turns out there is a way to address the problem with SteamVR—but it requires screwing around with some jank-ass command line tools. Because of course it does.

To make things quick, the fix that worked for me is the one outlined in this here reddit post. You’ll need to register with Valve as a developer in order to get access to the SteamVR tracking HDK, and then you’ll need to use one of the utilities in the HDK to gather some sensor samples from your Index’s inertial measurement unit (IMU). The utility has you rotate the Index to six different orientations, sampling at each, and then distills those measurements into a set of numbers indicating your accelerometer scale, your accelerometer bias, and your gyro bias.

You take those numbers and stuff them into a JSON file, and then you upload that JSON file to your headset with another CLI utility. And then you reboot your headset.

And then—well, hopefully, there is no “and then,” because that’s what fixed the issue for me. I can once again fly my spaceship without feeling like I’m sliding sideways across the deck.

Any chance we can get a built-in option to adjust this without having to bust out the command line, Valve?

Update, two days later: still broken 🙁

Sadly, the fix doesn’t seem to have done the trick. The tilt is back, as bad as before. I fear I’m going to have to RMA the headset. This is already my second Index—maybe the third time will be the charm.

Assuming I can successfully navigate the dark despairing caverns of Steam support. Wish me luck.