It is currently Tue Jan 28, 2020 11:53 am



Reply to topic  [ 6 posts ] 
 Head-tracking at home - Overview please 
Author Message
Two Eyed Hopeful
User avatar

Joined: Tue Feb 22, 2011 3:10 pm
Posts: 57
Reply with quote
Hi all,
I need head-tracking at home! What kind? 9DoF. Basically, I'd like to see that all of my head movements translate in a virtual space. Can someone give help by giving an overview on the devices and applications available today for such a feat? Please and thank you. I've searched the forum but have only found some problem-specific threads. I hope I didn't miss anything.

Background:

I have a VR920. Display quality aside, it is my first and only HMD and I think it's cool! Getting stereoscopy to work was challenging but I found I wanted to focus my efforts on the head-tracking. In fact, even if I had to spend a few hundred (one hundred preferably), I wanted to buy a dedicated solution for this that would work ideally. A blackbox solution from off-the-shelf that would have 9DoF of fluid head tracking with few quirks or problems. I wasn't able to find anything quite so simple. I was able to find lovely IMUs from sparkfun, but I'd need to interface them properly. I found that I might need some filters and algorithms to process the raw sensor data. Then I found that my Nexus phone has IMU sensors, and I spent a few days trying to get that to work.

So here I am. I thought I'd ask the pros. Maybe your insight can help me save time and actually get this done. Is it unreasonable to expect quality 9DoF headtracking, with a simple setup, for around 100$ or less?

Please and thank you,
Marco.

**EDIT**
I just wanted to relay what I wanted to do with such a device. I am a programmer. My ultimate goal is to attach the head-tracker's data to a camera in a virtual world. In my current experiments, I've made some scripts in Unity3D to do this. The scripts work fine, the head-trackers i've tried do not! Haha. But if there is an even simpler way, I'd love to hear about it. Also, I mainly work on OSX but if I need Windows or Linux, I can do this too.


Thu Jun 20, 2013 9:02 am
Profile
Golden Eyed Wiseman! (or woman!)

Joined: Fri Jul 08, 2011 11:47 pm
Posts: 1498
Reply with quote
Well, by saying '9DOF' you are basically saying you want a gyro/compass type sensor.

6DOF is the actual degrees of freedom you can move in, 9DOF is just a term used to describe sensors that have multiple sensing capabilities.

Really, you'll be best off selling your VR920, and buying a Rift and a Razor Hydra. Use the Rift for turning and the Hydra sensor for measuring position. That will give you true 6DOF positioning for the most reasonable cost. Of course, that is 4X the cost you wish to spend - I doubt you'll get a true 6DOF tracker for $100 or less that is suitable for VR. If all you want is measuring head turning, then you could possibly get a 9DOF chip for around that price, but it still wouldn't have real 6DOF positional tracking.


Thu Jun 20, 2013 9:12 pm
Profile
Two Eyed Hopeful
User avatar

Joined: Tue Feb 22, 2011 3:10 pm
Posts: 57
Reply with quote
Hi WiredEarp,
Thanks for the tips. And thanks for correcting my terminology.

OK 6DoF. I actually ordered a rift dev kit, but asked for a refund when I found out it didnt have 6dof. Still a great product but out of my price range if I still had to buy an IMU.

So for now I guess I'll stick with my VR920, and just sort out the head tracking for now. Then when I can afford a rift, I'll just use my already working head-tracker.

The Razer Hydra looks like a set of hand-held controllers. Did you mean that I should break one open and fix the tracking part to my head? Or am I looking at the wrong product.

I was kind of thinking of something along the lines of this. https://www.sparkfun.com/products/10736

But I have little experience with such things. Does anyone have any experience with such a product for head-tracking?


Fri Jun 21, 2013 5:04 am
Profile
Two Eyed Hopeful
User avatar

Joined: Tue Feb 22, 2011 3:10 pm
Posts: 57
Reply with quote
TrackIR5
No fuss, no muss? $150? Maybe this is the way to go.


Fri Jun 21, 2013 7:29 am
Profile
Petrif-Eyed
User avatar

Joined: Sat Jan 09, 2010 2:06 pm
Posts: 2255
Location: Perpignan, France
Reply with quote
mcsilvio wrote:
OK 6DoF. I actually ordered a rift dev kit, but asked for a refund when I found out it didnt have 6dof. Still a great product but out of my price range if I still had to buy an IMU.
The Oculus Rift does incorporate an IMU (accelerometer, gyroscope and magnetometer), but an IMU can only do rotational tracking, just like the Sparkfun you mentionned.

mcsilvio wrote:
The Razer Hydra looks like a set of hand-held controllers. Did you mean that I should break one open and fix the tracking part to my head? Or am I looking at the wrong product.
You don't need to open it, you can fix it to your chest or your head, like in these demos :
- Chest : http://www.youtube.com/watch?v=u-92rvc_Y-E
- Head : http://www.youtube.com/watch?v=ko5OdLE2Msw


Fri Jun 21, 2013 12:31 pm
Profile WWW
Golden Eyed Wiseman! (or woman!)

Joined: Fri Jul 08, 2011 11:47 pm
Posts: 1498
Reply with quote
Hey mcsilvio
TrackIR is not really good enough in my experience, simply due to having limitations on how far you can turn your head. Seriously, if you want VR i'd get a Rift, there is nothing cheaper that is really immersive.
As Fredz says, you can just attach the hydra handset through any means you wish. Alternatively, you can use a resistor mod (which means you can use your Hydra only with VRPN, which can limit its usability on some recent demos etc), or you can use a Palmer type mod where you just extend the wires to the tracking coils. That mod is a bit more tricky to accomplish, although still not particularly difficult. That should then work in any application, although you might still have positioning/calibration issues to work through.

All the '9DOF' gyro/compass systems dont actually even do true 6DOF afaik. They all have terrible translational drift due to only having accelerometers to detect translations. This is why the Rift, while having a 9DOF sensor, only actually returns true 3DOF, as those 3DOF are the accurate ones for this type of sensor.
This is why magnetic is better currently imho, but cheap optical tracking is surely just around the corner.


Sun Jun 23, 2013 5:49 am
Profile
Display posts from previous:  Sort by  
Reply to topic   [ 6 posts ] 

Who is online

Users browsing this forum: No registered users and 4 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group
Designed by STSoftware.