VR Motion Cancellation - Time to test!

Hey everyone,

development of a new Motion Compensation, based on the OpenVR Input Emulator is currently undergoing! I'm currently working on the code as much as possible to get things going again.

The biggest changes:
- Only Motion Compensation
- Only one MC mode: Reference Tracker
- Input Filter to prevent Jitter when using Bass-shakers

If you have a feature request, please don't hesitate to post it here.

If you own a MotionRig and want to test, join our Discord. But since I haven't posted enough to post external links, you have to got to Github, search for the user openvrmc, open the only repository available and on top of the Readme.md you will find the Discord link.

That sounds really good. My wish is, that not every steam vr update, it's broke. But i think, that is not really feasible. Another thing is maybe an option to disable 6DOF and only allow the Gyro (3Dof)...in my situation, i'm strong buckled in. i'm not really need a room tracking. And i really LOVE my bassshaker. i'm sure, no filter on the world could manage my shaker settings of love. ;D

Thanks noorbeast

I'm currently in touch with Bastiuscha and he will provide me a few Motion-Data logs to test some filters beforehand.

Hey Dschadu. Will this motion compensation work with the Rift S?

Hi Keith,
in theory every device that uses SteamVR to run should work. But Inside-Out Tracking is another challenge if have to solve, because the controller need to be in front of you.


I would like to take this opportunity to ask for some help:
I need help with the math. If anyone here want to contribute to the project and knows Quaternions, Vectors, Radians and that sort of stuff, please contact me! No programming knowledge needed. Any assistance is welcome and will speed up the development. You can find me on the discord I revered to above.

Hi Guys,

I think I've found it.
I've been fiddling around the last few days trying to sort out the damn vibration issue (really, really hate that the VR experience suffers so much with vibes).

I'd mentioned previously that I'd mounted my tracker on a stiff mounted post, rigidly attached to the upper platform structure to create a solid cantilever (tracker at the top near my head). This worked well to reduce the vibration for sim only use (a few stutters and position shifting here and there when racing, but still acceptable) but was not good enough after I added my 4 bass shakers and turned them up to full (horrible, sick feeling jitters when in VR).
After trying literally everything (gyro mounts, gel, silicone, memory foam, styrene, pendulous dampers, etc.) I finally found something that works...


At the top of my cantilever post (you can see the top of it extending up behind the set back) I found that adding mass absorbs the hell out of any vibration energy, even at full shaker power. In my case, I've duct taped 2x 500g (1 lb) steel weights from a weights vest I had lying around. I'm sure you can use anything you have lying around, you just need to have something to grab that energy so the tracker isn't thrown around.

I'm pretty hesitant to add any extra weight to the rig, but in this case I think it's well worth it!

I've only tried it for a few laps in iRacing, but it was perfect (I'd say 99% of how it is when motion tracking is disabled).
Fingers crossed lads. It would be great to hear how other people go

Tested it on different cars, tracks and different vibration and motion settings...
It works better than before. Much less vibration on the whole, but not entirely eliminated. The sharp sudden movements from the sim still cause a little bit of wobble, which I'll try and reduce with some damping.

On the whole it's much better, and combined with a software smoothing function from the tracker puck, it would be what most people are after for VR.
I'll post again if I have any luck

I had my first go with motion compensation.
Thanks to @Gabor Pittner for giving me a hint to give it another go since my earlier attempts didnt work out.

I dont have any bass shakers at the moment and it kinda worked.
Its needs to be mounted horizontally since we do not have much flexibility with offsets (in Advanced Settings) to correct it at the moment.
At the moment its mounted rigidly which as expected does suffer from glitches with sudden movements and vibration.
So I need to start re working it with some sort of vibration damping and start experimenting like you all have done.

Thought I'd share the model files for this if someone wants to try out some variation for damping.
I modeled it from subtracting the actual steam controller body that is given to us in the SteamVR files.
The controller hangs on really well. Feels like its suctioned on. It doesnt need anything else to secure it down.
So its convienent to put on and pull off at anytime which can be handy.

Also in the model zip folder are the other two mounts you see in the pictures for mounting vertical with the doughnut facing forward or back.
I printed these with the large opening upward with no problem.

Could you point out for me what the software smoothing function you are referring to is?

@DoctorD
I forgot to add your name in my last post
Could you point out for me what the software smoothing function you are referring to is?

@DoctorD
I plan to build something similar to your solution. Do you have any additional images on how you attached it to your chair?

Thanks!

Ive begun trials with damping the controller mount and had partial success with this arrangement below.
The black sheet is a dense type of packaging foam.
Its actually the packing left over from the original vive box.
But it still vibrates a little that makes reading gauges in the flight cockpit bit difficult.
I need to experiment more with different materials. With this setup, it should be easy to try many varietes of materials.



Even with the vibration it is still worth using the motion compensation right now.
Before I got this MC going, I was a bit discouraged lately as I couldnt get a good movement going in flight sims in VR.
It seemed to me I had built a large range 6 dof rig but couldnt use it to the full extent without feeing ill.

The feeling is fantastic when pulling back on the stick and pitching the rig back fully and not having my head swim about in the cockpit.

@JAD sorry if my wording was a bit off. I was referring to @Dschadu 's motion software in the future tense. At the moment I have flight simulation very playable with bass shakers and my 6dof. The relatively gentle nature of flight (even decent turbulence and such) is pretty acceptable in VR. No wandering head tracking and only minor jitters during touchdowns and heavy dogfighting and carrier takeoffs.

iRacing is another story completely. If I want anything coming through the actuators like you'd expect in a real stock car or open-wheeler (like heavy gear shifts, ripple strips, fast straights, etc) then I the tracker jitters regardless. It's playable, but the I need to turn things down a good 30-40% to make the tracker behave. The bass shakers don't cause any fuss. It's just the sim now that I need to sort out.

I'm a civil/mechanical engineer, but I have a business acquaintance that specializes in acoustic/vibration isolation (buildings) that I'll try and chat with tomorrow. Hopefully he can spare some time to get some proper science applied to our dilemma!

@Dschadu please let me know when you have the new beta link up and I'll happily be a tester

@DoctorD I see now, no problem.

Couple thing Im going to try next is -
-add mass like you have,
-and Im ordering some RC car oil and spring dampers so I'll try and incorporate them into the mounting.

This looks promising.
Just waiting for RC suspension dampers to arrive and fix to the 4 corners.
This is 3mm stainless wire rope.

Hi guys,

pleased to see that there are things going on about motion cancellation .

I have a question for you: I have a motion rig (simtools, 4DoF, geared motors, Bass shakers, 32inch monitor integrated on motion platform).

I want to buy a VR helmet to play in my motion rig (Assetto Corsa, DCS in priority).

Taking into consideration the needed motion cancellation to add to the setup, which VR helmet would be the more « compatible » with the ongoing motion cancellation solutions ?
(for example: The Rift S has integrated motion sensors, will this be a problem/limitation for some motion cancellation solutions ?
(I’m not new to VR, since I own a PSVR, but after wasting many hours trying to have something playable I decided that going for a real PC VR helmet will be much more simple ).

@the2jakes : Best solution is a HMD with outside tracking, i.e. the lighthouse solution from HTC/Valve (Index, Vive, Pimax). Inside-Out tracking can catch your rig as reference for movement and therefor it wouldn't work. Or your image jumps while it follows your rig, then your wall, your rig...
keem85 (don't know his name here in forum) reported the Rift S as working, but @SilentChill had issues with his HP Reverb. So your mileage may vary

@thejakes2,
As far as I understand, no VR headset Can do motion compensation properly. When one of the sim software Companies (SimTools, FlyPT etc) can output the 6DoF absolute position and orientation data, then someone will be able to make motion compensation work outside of lighthouses and hand controllers being attached to rigs.