My homebrew Tuscany Hydra demo

[Falan]

Oh this could be great! Imagine inputting the dimensions of your office/room along with chair/table position - measurements etc You could walk around and sit down at the desk but instead of some crappy office chair/table in reality instead you could be sitting at a wooden table in Hogwarts library, flick open your virtual book and take in the atmosphere!

That blend of reality and VR would be pretty crazy. I guess thats more AR though, still the futures looking bright isnt it. Great job on the hydra demo above btw! Maybe make a zombie demo where instead of chainsawing their limbs off instead you have a few buckets of rotton tomatoes laying around you can pick up and throw at them for now

[V8Griff]

That is awesome, thanks for sharing that and the reaction of your children is just so good.

The accuracy of the Hydra seems to be an awful lot better than postings had led me to believe and your quick integration of the head tracking is an excellent piece of work.

Looking forward to working with the Hydra now(On European backorder) and I hope that Oculus are looking at incorporating this technology into either the next Dev kit or the consumer version as it is the way to go.

[OzOnE2k10]

Wouldn't the 2 hydra systems interfere with each other?

Hmmm, that's another interesting idea to play around with...

I think what you'd need to do with 2 sets is to disable the transmitting coils in the second base unit.
The problem then is that the pulses won't be synchronized between the two systems...

The Hydra base unit "sends" the three 2ms pulses in sequence, so the hand units are of course expecting to receive those pulses at the same time.
The DSP in the second Hydra's base would need to be modded to be in sync with the pulses of the first base unit. This will be tricky.

(props to @janoc and others for the above info)

I ordered a Hydra last week, so I'll have a look at capturing the serial protocol from the joysticks etc.
I did expect the Hydra controllers to be a bit more complex inside, but I guess all the clever stuff is done by the DSP.

Would anyone be especially interested if the Hydra hand controllers could be made wireless?
The fact that the coil signals sent to the base are analog simplifies things a bit, but they would probably need to be sampled for wireless transmission.

[V8Griff]

Professional systems like Polhemus and Ascension have separate frequency modules installed inline with the source (Base unit in the Hydra's case) so that different sources can operate in the same environment and the signal transmitted is read by different receivers so they don't interfere with each other. It would therefore be possible to add a third receiver for head tracking, although the Virtuality systems just had one receiver for head tracking and one in a single joystick for use in either your left or right hands

[mrklaw]

the guy from sixense said the prototypes were wireless, it was just razer's choice to make them wired, probably for cost reasons. although isn't the range limited, so making them wireless is more for convenience/less tangling rather than increased range?

if so, you could mod them to stay wired, but have easy breakaway cables like old Xbox controllers or a magsafe connector?

[Parallaxis]

So we have the magnetic field sensors providing us with an absolute position (relative to the station). This is operating at a relatively slow rate compared to the Rifts sensors.

We also have some pretty fast 1000hz accelerometers.

How about fusing the data from the accelerometers to fill in the gaps between the input from the Hydra. This way the system can predict change the direction of the movement at a rate of 1000hz and change direction and then wait on the absolute position for correction. The key here is to get the fastest possible update on directional data to avoid getting sick from the lag of directional changes.

This is some kind of movement antialiasing / interpolation. I guess this is pretty complicated programming, but Oculus is already working on predicting your movement with the software with the rotational stuff.

Now there is a lot of talk about Carmack saying that the Hydra sensors won't work for this thing - but that's not really true. Watch this:
http://www.youtube.com/watch?v=NYa8kirs ... age#t=620s

Now he is saying that the angular precision is not good enough, not the positional data. But remember that the Rift has build in ultra precise sensors taking care of that.

[TheHolyChicken]

I just ordered a hydra. There's just been too many demos and too much promise for the device for me to ignore it, and it looks to me at this point that the hydra is set to be "the" vr controller for the near future. Be sure to use the 50% off deal: http://www.razerzone.com/VRpromo/?utm_s ... cat_ban_us

[mrklaw]

I just ordered a hydra. There's just been too many demos and too much promise for the device for me to ignore it, and it looks to me at this point that the hydra is set to be "the" vr controller for the near future. Be sure to use the 50% off deal: http://www.razerzone.com/VRpromo/?utm_s ... cat_ban_us

me too. The original Tuscany update from sixense plus this is too much already, and the potential is clear - even just from a prototyping point of view.

Hopefully when sixense release their Tuscany demo with object interaction, it can be modded to add in positional tracking like this - that'd be a great combination

[marbas]

They would. As I understand it, the Sixense technology supports multiple base stations using different frequencys so that you can use more than one in the same area. However all Hydras are on the same frequency. The technology also supports up to 4 devices per base station, but again Hydra only supports 2.

So, "ideally" Sixsense/Razer/(Oculus?) could sell a small lightweight addon-device to be attached to the Rift and work on an existing single Hydra system. Also 3 units and 1 basestation. Would this technically be possible, by for example just upgrading the existing hydra firmware to support 1 additional piece of hardware?

And yeah, "the hydra needs to be wireless" is the first idea that struck me when I first tried my hydra 1/2 years ago.

[Parallaxis]

that worked a lot better than what Carmack was saying, so glad i bought a hydra now

No, Carmack just said that the angular precision was pretty bad, but the rest. Look here:
http://www.youtube.com/watch?v=NYa8kirs ... age#t=620s
It's at 10.20

The Rift have other more precise sensors for that. So it's all good.

[geekmaster]

So we have the magnetic field sensors providing us with an absolute position (relative to the station). This is operating at a relatively slow rate compared to the Rifts sensors.

We also have some pretty fast 1000hz accelerometers.

How about fusing the data from the accelerometers to fill in the gaps between the input from the Hydra. This way the system can predict change the direction of the movement at a rate of 1000hz and change direction and then wait on the absolute position for correction. The key here is to get the fastest possible update on directional data to avoid getting sick from the lag of directional changes.

This is some kind of movement antialiasing / interpolation. I guess this is pretty complicated programming, but Oculus is already working on predicting your movement with the software with the rotational stuff.

Now there is a lot of talk about Carmack saying that the Hydra sensors won't work for this thing - but that's not really true. Watch this:
http://www.youtube.com/watch?v=NYa8kirs ... age#t=620s

Now he is saying that the angular precision is not good enough, not the positional data. But remember that the Rift has build in ultra precise sensors taking care of that.

In that video, John was saying the Hydras had an ATTITUDE drift problem, not a problem with position. So yes, using the Hydra for head position and using the Rift for attitude may be a great solution.

Is anybody working on changing the operating frequency of the Hydra, so multiple of them can occupy the same space like the next gen Hydra prototypes? It would be nice to use a pair of Hydras for head and hip tracking, and another both hands.

[OzOnE2k10]

It may be possible to mod the controllers so they filter out the pulses from the other base station...
The problem is, the frequency of the pulses at the base station are likely driven directly by the DSP, so it would require changing the firmware (unlikely), or overclocking / underclocking the DSP's master clock to change the pulse freq.

This could cause problems with the DSP-to-USB interface and other issues though (USB probably integral to the DSP?).

On Jan's page, it looks like two of his oscillograms are showing a freq of around 13KHz for the pulses themselves...
http://janoc.rd-h.com/archives/212

Now, I didn't do too well with AC theory at college, so I don't know how to check the resonant freq of the opamp circuits unless I drop the diagram into Proteus or something?

When my Hydra arrives, I'll be able to investigate this stuff further.
If the base station uses an external circuit for generating the coil pulse frequencies, it would be easier to mod for multiple units.

Does anyone with a Hydra fancy taking the base unit apart to take some photos of the board(s) etc.?


btw, my Hydis panel arrived today. It has a dinky little controller board which uses a separate MCU and scaler (RTD2120 and RTD2545).
I found pretty much all the software and diagrams I need to do firmware mods on the Realtek chips too.

I don't think it will be as easy to mod this controller for backlight pulsing (motion blur reduction) using the DVI input 'cos it doesn't look like the scaler has a direct VSYNC output.
But, I should be able to test the theory using the VGA input.

[Parallaxis]

In that video, John was saying the Hydras had an ATTITUDE drift problem, not a problem with position. So yes, using the Hydra for head position and using the Rift for attitude may be a great solution.

Is anybody working on changing the operating frequency of the Hydra, so multiple of them can occupy the same space like the next gen Hydra prototypes? It would be nice to use a pair of Hydras for head and hip tracking, and another both hands.

Yes attitude, that was the word I was looking for.

How is the Hydra separating the two controllers? Different frequencies or are they timed receiving every other pulse or something like that?

[Okta]

It is a massive shame the KS was too early. This functionality really is a must for a VR head set. Hoping Oculus can release an add on sensor that will be part of the SKD going forwards.

[WiredEarp]

@ V8Griff:

although the Virtuality systems just had one receiver for head tracking and one in a single joystick for use in either your left or right hands

The Virtuality systems did have hip sensors as well. Did it do these via a different method instead of magnetic?

[EdZ]

How is the Hydra separating the two controllers? Different frequencies or are they timed receiving every other pulse or something like that?

All the Hydra's controllers do is listen to the pulses put out by the base station. Both controllers listen to the same pulses. The recorded signal is amplified at the controller, then sent back to the base station to be processed to determine the position & orientation. Apart from the buttons and sticks, the controllers are just dumb receivers. The limitation of two per basestation is more that there isn't another connector on the back of the base station to connect more controllers.
I suppose Sixense could release a 3-controller wiring loom and use TDM to add in another channel at the expensive of update rate (60% of the two-controller rate), but only if the base station was built to accept such an addition.

[rupy]

Yes, this works! The sensors complement each other!

I would wait until razer announces the Rift Hydra kit with headmount magnetic sensor before ordering anything.

Can someone make sure razer and/or oculus are working on this?

It's too important and needs to be standardized quickly in order to avoid fragmentation.

Neil?

[geekmaster]

How is the Hydra separating the two controllers? Different frequencies or are they timed receiving every other pulse or something like that?

All the Hydra's controllers do is listen to the pulses put out by the base station. Both controllers listen to the same pulses. The recorded signal is amplified at the controller, then sent back to the base station to be processed to determine the position & orientation. Apart from the buttons and sticks, the controllers are just dumb receivers. The limitation of two per basestation is more that there isn't another connector on the back of the base station to connect more controllers.
I suppose Sixense could release a 3-controller wiring loom and use TDM to add in another channel at the expensive of update rate (60% of the two-controller rate), but only if the base station was built to accept such an addition.

The Hydra API supports 4 controllers per base station, so perhaps a simple hardware mod is in order to hack an extra pair of Hydra handsets together with a single base unit. The Hydra firmware may already support 4 controllers.

[Parallaxis]

Yes, this works! The sensors complement each other!

I would wait until razer announces the Rift Hydra kit with headmount magnetic sensor before ordering anything.

Can someone make sure razer and/or oculus are working on this?

It's too important and needs to be standardized quickly in order to avoid fragmentation.

Neil?

I actually wrote to Palmer a couple of days ago about this (don't expect reply). But I suspect they already know this and that they are working with Sixence/Razer on this.

[rupy]

I actually wrote to Palmer a couple of days ago about this (don't expect reply). But I suspect they already know this and that they are working with Sixence/Razer on this.

Let's hope so, this is too good to get screwed up by fragmentation! I PM'ed Neil, posted on Oculus dev forum and mailed Oculus support.

[mattyeatsmatts]

I actually wrote to Palmer a couple of days ago about this (don't expect reply). But I suspect they already know this and that they are working with Sixence/Razer on this.

Let's hope so, this is too good to get screwed up by fragmentation! I PM'ed Neil, posted on Oculus dev forum and mailed Oculus support.

But did you write it on a banner that is attached to a plane that is constantly circling the Oculus office?

[phillypro]

i guess things look best through the eyes of children

[Parallaxis]

But did you write it on a banner that is attached to a plane that is constantly circling the Oculus office?

I broke into Oculus VR HQ last night and tattooed it on Palmers feet. That way everybody can see it always. (yes he actually sleeps there)

[marbas]

The Hydra API supports 4 controllers per base station, so perhaps a simple hardware mod is in order to hack an extra pair of Hydra handsets together with a single base unit. The Hydra firmware may already support 4 controllers.

What happens if you use both controllers (or 2 addons) for head tracking and fuse the data from both controllers. Better headtracking data?

[TheLostBrain]

Simply awesome! This video definitely conveys just how important positional tracking is to the overall experience.

As an aside...my god you seem to be getting a TON of range on your hydra!
Hell, I can't even seem to get a foot away from the base station before it's jitter city...to the point of it being unusable.

While, admittedly I haven't really spent more than a few minutes total playing with it, I did try a few different locations attempting minimize any interference.
Anyone else experience this? Maybe mine's just defective?

Awesome work man!

[brantlew]

Simply awesome! This video definitely conveys just how important positional tracking is to the overall experience.

As an aside...my god you seem to be getting a TON of range on your hydra!
Hell, I can't even seem to get a foot away from the base station before it's jitter city...to the point of it being unusable.

While, admittedly I haven't really spent more than a few minutes total playing with it, I did try a few different locations attempting minimize any interference.
Anyone else experience this? Maybe mine's just defective?

Awesome work man!

I never had range problems with mine. Only when I put it close to my monitors to I experience jitter.

[Parallaxis]

Simply awesome! This video definitely conveys just how important positional tracking is to the overall experience.

As an aside...my god you seem to be getting a TON of range on your hydra!
Hell, I can't even seem to get a foot away from the base station before it's jitter city...to the point of it being unusable.

While, admittedly I haven't really spent more than a few minutes total playing with it, I did try a few different locations attempting minimize any interference.
Anyone else experience this? Maybe mine's just defective?

Awesome work man!

Have you tried the Sixense drivers? The ones from Razer are terribly dodgy.

[jf031]

Amazing that a useable positional tracking solution has been produced less than a week after the first main Kickstarter shipments. There are undoubtedly some problems with this method, but it is probably more than good enough for enthusiasts and developers to play around with.

I really, really, really want to be able to look over railings, lean to look around corners, and otherwise adjust my head position to get a better/different view of what I'm trying to look at in virtual worlds. Standing in place, and then being able to duck down, lean side to side, etc., will be a much, much more immersive experience than just standing (or sitting, most likely) there, being careful not to do anything but rotate my neck.

I hope this becomes integrated in almost every demo and Doom 3 BFG/original Doom engine (including Hexen, etc.)/Quake series source ports. Although it wouldn't work well with the original gameplay in any of the latter*, I personally just want to explore those worlds. So, I say: disable enemy awareness of the player (or, optimally, get rid of the enemies altogether), and use no-clipping on demand to pass sections that would require engagement of the enemy.

I'm very happy that I bought a Hydra months ago.

* Due to player bounding box issues, for one -- although Doom 3 uses per-poly hit detection (maybe Doom 3:BFG doesn't, though, as it uses parts of Rage's engine, idiotically so in at least one case: texture storage is re-done per map, so each map takes up much more space than the .bsp/logic/whatever else code, even though textures are repeated [to an extreme degree] level-to-level; I could be misinformed about this, though), but then inverse-kinetics would need to be used to model the movement of the body while ducking, leaning, etc.

[rupy]

I actually wrote to Palmer a couple of days ago about this (don't expect reply). But I suspect they already know this and that they are working with Sixence/Razer on this.

Let's hope so, this is too good to get screwed up by fragmentation! I PM'ed Neil, posted on Oculus dev forum and mailed Oculus support.

But did you write it on a banner that is attached to a plane that is constantly circling the Oculus office?

LOL, I guess I should relax a bit, I'm a bit scarred from J2ME (pre-iphone/android java game development)!

[hidden2u]

Congratulations tbowren! This is a problem that people have been wringing their hands over for a while and you solved it just using retail hardware.
Any naysayers just need to watch your youngest son trying to look through those chairs and peer over the ledge to see that it works good enough to fool the brain.

[Parallaxis]

I really like that Dan from Sixense or the guys from Oculus hasn't really made a statement about this and are mostly keeping quiet. That a good sign and a sign of something brewing at HQ.

[marbas]

Congratulations tbowren! This is a problem that people have been wringing their hands over for a while and you solved it just using retail hardware.
Any naysayers just need to watch your youngest son trying to look through those chairs and peer over the ledge to see that it works good enough to fool the brain.

Kudos @tbowren for showcasing using the hydra for head-translation. But there has been discussions on this forum about using the hydra for this application all the way back since the Oculus kickstarter.

[MrGreen]

I really like that Dan from Sixense or the guys from Oculus hasn't really made a statement about this and are mostly keeping quiet. That a good sign and a sign of something brewing at HQ.

The amount of wishful thinking here is priceless.

That being said, I'm with you on this one. The involvement of Sixense with the demos and even on this forum leaves little doubt in my mind that they're on to something.

Or they just want to get those damn Hydras out of the freaking warehouse once and for all...

[Parallaxis]

Congratulations tbowren! This is a problem that people have been wringing their hands over for a while and you solved it just using retail hardware.
Any naysayers just need to watch your youngest son trying to look through those chairs and peer over the ledge to see that it works good enough to fool the brain.

Kudos @tbowren for showcasing using the hydra for head-translation. But there has been discussions on this forum about using the hydra for this application all the way back since the Oculus kickstarter.

True, but because Carmack made a statement about the attitude issues back then, the common opinion about the Hydra was that it wouldn't work properly. Tbowren actually demonstrated that combined with the new sensors of the Rift, the problem actually didn't exist anymore. So that's kindda important for this little community anyway.

I wonder if the team at Oculus has arrived at the same conclusion? With a 2. dev kit slated for Q3 this year, you can be pretty sure that they figured something out for positional tracking already. There is no way they would launch a second dev kit without that feature. It would not make any sense, because it's essential for developing for this thing.



(yes... tons and tons of wishful thinking, I know)

[donkaradiablo]

I think in the upcoming months, mini games are going to be awesome to showcase the potential of VR. Much easier than creating a whole set of assets for a new game, more VR focused than creating mods for an existing game.

Possible example based on this demo, step by step:
1. Using the other hydra controller to control a lightsaber.
2. No HUD, a big timer on your arm (you're supposed to cut everything marked with an X as fast as possible).
3. Leaning may be a time saver (with targets like the window frames).
4. Cutting down anything that you were not supposed to cut costs you secs.
5. The marked items change everytime you start the demo.
6. You can submit your score (time) to a scoreboard on a website and facebook.
7. Instead of an invisible hand like the Sixence demo, an arm like Six element, or a hand and an arm that gets invisible gradually.

Keeping it simple like the original Wii games, but with a lot more immersion.

My first idea was a "fruit jedi". You stand on an X mark, just look around in 360 degrees and cut down every fruit that falls around you As it doesn't involve movement, it could be very immersive. Or you could stop fruits from hitting the floor with the help of a baseball bat. Everytime a fruit hits the floor a note is played and and when the melody is over, it's game over.

[MrGreen]

God you've just summoned Fruit Ninja VR edition. Of course that was coming...

[nateight]

My first idea was a "fruit jedi".

Uhhh...
[youtube]http://www.youtube.com/watch?v=CG__PZzNfkw[/youtube]

[Mystify]

I feel like a fusion of the rift and hydra could be pretty great. A single base station for the magnetic tracking, integrate the rift sensor into the hydras for improved rotational precision, and have it all function together as a coherent package.

[donkaradiablo]

@nateight, I was thinking more like
1. A 360 degree game, fruits falling all around, you look up, you see two coming, you cut one, and turn around and cut the other while crouching a little
2. And since it's fixed in place, maybe the gfx could use real-time HDR image based lighting.

[youtube]http://www.youtube.com/watch?v=OZIOHt4igJA[/youtube]

Modable by changing the models and HDR images. Mods coming soon with hell and demons

[luckybarry]

This video highlights to me something that hasn't come acrossin all the other vids i've watched so far, the wonder of kids experiencing something for the the very first time love the reactions and the obvious enjoyment