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 Red Rovr Motion System (formerly Friispace) 
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Petrif-Eyed
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I'm mounting bulky motion tracking equipment on top of the headphones. I guess I don't have to mount it on headphones - per se, but it is a convenient location. Earphones will work fine, but I still need a stable mounting point on the top of my head. I might also be able to get away with a mount point on the back of my head (maybe counterbalanced with HMD). Any suggestions?


Sat Apr 28, 2012 1:31 pm
Petrif-Eyed
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Project Video Update:



I have not talked much lately about this project, but I have been working like crazy on it. There have been a lot of technical problems solved and some significant redesigns in order to get it to the point where I can do field-testing. The video shows at what stage of development I am at. I have an untethered and functional back-top unit now, and the system has been fully scaled. This only shows a basketball court, but I have done field testing on a football field and it scales to that size as well.

The motion detection algorithms are still prototype and need a lot of work. There are some obvious flaws and delays that are clearly visible in the video. But the motion control works well enough now for me to continue developing boundary enforcement and redirected motion (none of which is shown in this video). I am particularly satisfied with how well the independent head/torso motion is working. This game (theHunter) does NOT support independent head motion - just mouse-look and WASD - so all of the walking and looking around that you see is derived from that basic interface.

I am not going to go into too many details about the technology, because I am thinking about turning it into a commercial product. The timeline is difficult for me to estimate because there is still a lot of R&D and some incredibly difficult problems to solve, but I would like to get it to market by the end of the year. Maybe some beta testing to forum members would be available earlier.

In the meantime, I've still got tons of development to go. Also, I bought SkyRim when it first came out, but I have not allowed myself to play it, because I knew it would suck my time away and distract me. My goal is to alpha-test this technology with SkyRim. Perfect timing for my ST1080 to show up as well :)


Last edited by brantlew on Mon Sep 10, 2012 4:53 pm, edited 1 time in total.



Tue May 08, 2012 12:21 pm
Sharp Eyed Eagle!
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That is Rad! How is the level of immersion at this stage? This is close to my ideal VR setup.


Tue May 08, 2012 7:31 pm
Golden Eyed Wiseman! (or woman!)

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Looks great! Can it only track the one set of sensors currently?
The immersion must be way better with the ability to walk around.


Tue May 08, 2012 7:40 pm
Petrif-Eyed
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@FingerFlinger: Right now the immersion is not good because it's so dangerous! I'm usually testing this outside at nighttime, and without boundary enforcement I am constantly in fear of smashing into goal posts and other obstacles. I've twice come within half a meter of crashing right into a pole. The first time I tried to film this was on a bright and sunny day so I had to use a blinder. I ended up smashing right into my camera and nearly broke it. There are some other frustrating glitches that take me "out of the moment" but all-in-all it's pretty cool. I think once I get boundary enforcement working and the ST1080 and/or the Oculus Rift, I will be be able to relax and really get in to it.

@WiredEarp: If you mean does it currently only track a single point, then yes.
There are some very subtle things that add to the immersion in a big way. Though it doesn't match your head bob in 6D, it does mimic the slight bounces of your head as you walk which is something you don't experience on a stationary system. Also the "quasi"-independent head motion is a real winner. It seems to add to your environmental awareness to be able to turn your head and scan the surroundings as you walk in a straight line. You start to realize how bogus the movement in a FPS is - all those strafe motions and the start/stop/scan habits that you pick up. Independent head motion is more natural and informative.


Tue May 08, 2012 9:49 pm
Golden Eyed Wiseman! (or woman!)

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For a starting point, you could make it just play a tone when approaching a border - that would be way easier than integrating visual cues.

For a game that doesn't support proper independent head motion, it really looked pretty good! I agree about the little head movements adding a lot to immersion.

I'd pay good money for a system like this that could support 12 players locations. I'd only need the location/direction vectors, since I could use devices such as a Hydra in a backpack to provide head/gun/hip tracking.


Tue May 08, 2012 10:10 pm
Petrif-Eyed
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WiredEarp wrote:
I'd pay good money for a system like this that could support 12 players locations. I'd only need the location/direction vectors, since I could use devices such as a Hydra in a backpack to provide head/gun/hip tracking.


Getting 12 accurate x,y locations is relatively simple, but getting accurate direction vectors is really freakin' difficult because the yaw sensors are all so "drifty". But you HAVE to have perfect yaw vectors if you want to put players in the same play area. So that's the rub. Players must stay in the same reference frame or else they will start smacking into each other. Compounding the problem is the fact that not only must you have perfect yaw in the real-world, but you must have perfectly aligned yaw in the virtual world as well. In other words - a 90 degree turn in the real world corresponds to exactly a 90 degree turn in the virtual world - otherwise we have frame drift again and bruised players. Mouse emulation is inherently drifty. So without game supported absolute yaw, we're doubly screwed.

Luckily for single player the reference frame can drift all over the place without consequence. In fact, that's the whole point of redirected motion. But open environments and redirected motion are totally incompatible with shared multi-player areas. The best you can do is have a partitioned play field with each player running around in their own little area.


Tue May 08, 2012 11:12 pm
Golden Eyed Wiseman! (or woman!)

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Quote:
But open environments and redirected motion are totally incompatible with shared multi-player areas.


If you have accurate enough yaw you don't need redirected motion for a shared space, you can simply render the other players in the 3D world and let them avoid them in that way. That way, lots of players can share the same area.

I know what you mean about mouse emulation and single player accuracy etc, for any serious VR role mouse emulation will never cut it IMHO, so I only consider it for playing games using VR tech, not for real VR.


Tue May 08, 2012 11:38 pm
3D Angel Eyes (Moderator)
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Looking good. Nice work.

One thing I noticed, though, is it seems you are moving very far in real life, but only moving slightly in the game. Was this intentional?

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Wed May 09, 2012 5:43 pm
Petrif-Eyed
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Just depends on what the default game walking speed is. Whatever the "W" key does is what I do. So if the game supports configurable speed then you can calibrate it to your walking speed. I'm also sort of "overwalking" it just to make sure the input signals are clear but I could slow down a little to match the game a bit better. Actually this game has a more realistic walking speed than most because it's designed as a simulator (of sorts). I've noticed that the default speed in SkyRim on the other hand is closer to a run.


Wed May 09, 2012 6:47 pm
Golden Eyed Wiseman! (or woman!)

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Very, very cool! Cannot wait to see this completed, I would definitely buy it as a product.


Wed May 09, 2012 8:54 pm
Petrif-Eyed
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Quick update: Important milestone tonight. I just walked about 40 minutes (maybe 2 miles) on a virtual forest path, while actually walking in circles on a real football field without ever exiting the field or smashing into anything. So the redirected motion seems to be working. It took me about 20 minutes to fully trust the system, but once I realized that I wasn't going to hit anything, I was able to just relax and immerse into the scenery. It felt pretty cool.


Mon May 28, 2012 1:12 am
3D Angel Eyes (Moderator)
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Very cool.

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Mon May 28, 2012 11:00 am
Sharp Eyed Eagle!
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That is really awesome! To what degree were you able to detect that you were actually walking in a circle, as opposed to a straight line?


Mon May 28, 2012 11:06 am
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Probably a terrible idea, but if you had a high enough resolution tracking camera, you could put an array of three IR balls on your head. They'd be arranged in a triangular pattern (duh) with one farther out than the rest (like the vertices of a slice of pizza).

This way, you can get the absolute position and direction of each player (you just have to be careful to not mix-up the players' balls).

Also, I know that Crysis supports absolute yaw (and other angles) in modding.


Mon May 28, 2012 2:00 pm
Petrif-Eyed
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@zalo: I considered that at one point - using optical tracking for both body and head orientation but the resolution of a Wiimote is just not good enough. The only work around would be to mount poles to a helmet in order to enlarge the triangle, but that quickly becomes unwieldly. Some sort of custom camera could work, but it would probably be expensive to get the required resolution. PalmerTech's company has some sort of VR room that it contracts for the military that uses optical technology this way.
http://www.mtbs3d.com/phpBB/viewtopic.php?f=120&t=13779
But even with that kind of money, they don't scale to the sizes that I am looking at. So for practical reasons doing localized head tracking seems to be the best way.


@FingerFlinger: The game I use for testing (theHunter) encourages long, straight, uninterrupted walks so it is probably the worst-case scenario for this system. My testing has shown the curvature limit for imperceptible turning to be somewhere between 2 and 3 degrees/sec. This radius is a bit too large to fit well within a 150 foot square however and I end up intersecting the edge more often than I want to. I found a "sweet spot" between 3 and 4 degrees/sec that is just slightly perceptible but reduces edge collisions to a low level. I now come within 2 meters of an edge about once every 7 minutes at which point the system gives me a very noticeable "nudge" to keep me in bounds. The bad news in all of this however is that basketball courts in general are just going to be too small to implement redirected motion very well. I have done testing at 10 degrees/sec that would keep you in that space but the turning is very perceptible at that point. Of course, games that encourage more sporadic movement patterns may work better in smaller areas, but I haven't done that testing yet.


Mon May 28, 2012 4:29 pm
Sharp Eyed Eagle!
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Even though your test wasn't perfect for basketball court size, I think it is very encouraging. I'm sure it is possible to design levels that work very well within more constrained areas. And coupled with some extra tricks, it could be pretty robust.


Tue May 29, 2012 12:04 pm
Petrif-Eyed
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I assume one of the "tricks" you are referring to is accelerated turning. It's been well documented that you can greatly overshoot or undershoot an in-game turn without the player noticing to make large angular corrections. I've been a bit apprehensive about using this approach however - mainly because I don't independently track the torso and head. So I can't differentiate between a real full-body turn or just a head turn. In my opinion the difference is significant. With a torso turn, the only frame of reference is the environment so by moving the frame you can fool the player. But a head turn has a second reference frame - your neck. You can "feel" the relative angle between your head and your body. So if you stand still and move your head from left to right, and back again - the original left view should be intact. You will sense that the environment moved because of the disparity between your eyes and your neck. Exaggerating this effect for comic purposes - you can make the environment spin around you just by shaking your head "no".

...but in a small play area, you would probably be forced to use such techniques.


Last edited by brantlew on Tue May 29, 2012 7:57 pm, edited 1 time in total.



Tue May 29, 2012 1:13 pm
Sharp Eyed Eagle!
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Yeah, I see your point. I think there is probably still some utility there, but since I mainly want to develop a theory for designing VR experiences, I guess I'll find out what the limits are.


Tue May 29, 2012 7:49 pm
Petrif-Eyed
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Sounds great. Data in this area is badly needed. There are only a few research groups that have worked on this publicly and typically in a very limited fashion. The findings tend to be based on either extrapolations of small scale testing, or just flat out simulated results. The real field testing is probably all military contract and not publicly available.


Tue May 29, 2012 8:15 pm
Petrif-Eyed
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I worked through a bunch of issues and glitches the last couple of weeks so that tonight I was finally able to play SkyRim in FriiSpace. I barely know the SkyRim controls and the FriiSpace motion system is not precise enough yet to handle fast paced combat situations, so I stayed up in the mountains and avoided people the best I could. But it still made for an amazing experience. Free walking is just such an intuitive interface - I would go for 10 minutes at a time without even having to hit a button. You get so used to the normal sensations of locomotion that I found myself trying (and failing) to crouch and duck around stuff. At one point I was up on a ledge and saw a deer down below me, and I just naturally went to one knee and tried to crane my neck to see through some foliage. Sucks that the game interface is not flexible enough to support that granularity of motion. Also, redirected motion works really great! Before - when I was specifically testing it, I could sense it. But when you trust in the system and just concentrate on your surroundings and moving through complex terrain, you don't notice it at all. It is really strange when you finally take off your headset. You have to look around for a few moments to figure out where the heck you are. A last observation - moving steeply uphill and downhill is a strange sensation. You are looking up but your legs are not climbing and it's a bit confusing.


Thu Jun 07, 2012 12:40 am
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That sounds like some nice progress, brant! Redirected motion in particular sounds like something that should only work well in theory, so I'm kind of fascinated to hear of it actually working well in real life. :)

How bad was the dissonance when you ran into something like an unexpected collision volume in-game but kept walking in real life? Also, have you thought about trying out FriiSpace in a homespun application where you can test it with a 1:1 mapping rather than keyboard/game pad emulation? While perhaps not useful for retrofitting games, I think it'd be a good exercise for the technology.


Thu Jun 07, 2012 10:24 am
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BillRoeske wrote:
Redirected motion in particular sounds like something that should only work well in theory, so I'm kind of fascinated to hear of it actually working well in real life.


It's funny because initially the things that I thought were going to be simple about this project have turned out to be much more challenging than I expected, while the thing that seemed the most experimental and high-risk (redirected motion) turned out to be the simplest. I can honestly say that redirected motion is the best functioning and most impactful part of the system. But the code is almost embarrassingly simple and took me just a couple of evenings to work out - a rare and satisfying experience for me as a coder. I think people are turned off by the amount of space that you need to operate in, but it really is worth it. It has to be experienced to be appreciated.

BillRoeske wrote:
How bad was the dissonance when you ran into something like an unexpected collision volume in-game but kept walking in real life?


Not really too bad right now. The controls are a bit soft and "cartoonish". I think if you had finer control, you might get some perceptual dissonance and even VR sickness, but since they are so far from perfect it doesn't get that weird. The thing that kept happening to me though is that I kept unintentionally walking through plants and tree branches since the motion control is a bit wonky - and in 3D it makes you flinch.

BillRoeske wrote:
Also, have you thought about trying out FriiSpace in a homespun application where you can test it with a 1:1 mapping rather than keyboard/game pad emulation? While perhaps not useful for retrofitting games, I think it'd be a good exercise for the technology.


Right now, I am just trying to get a simple, low-cost system working that people can use for gaming. It works in my favor right now that the game control interfaces are so limited, because the simple version of this system is so inherently imprecise anyway. I have a lot of ideas for much more complex setups and multi-sensor fusions that would allow for more precision and more degrees of freedom. Those would be fun to integrate with some custom rendering software to see how closely you could match reality. I might get into that kind of thing a bit down the road.


Thu Jun 07, 2012 11:21 am
3D Angel Eyes (Moderator)
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This is sounding better and better. Nice work.

Also, are you going to make a video?

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Thu Jun 07, 2012 5:53 pm
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Very excited about this, great progress. :)


Thu Jun 07, 2012 11:42 pm
Petrif-Eyed
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@cybereality: Those in-game videos are really hard to put together, and right now there is not much new to show. The motion control is identical to the last video I uploaded. A redirected motion video would just be a whole lot more of the same. When the motion tracking improves I will post another video. However I have thought about posting a satellite view showing the redirected path that I take during a game session.


Fri Jun 08, 2012 12:09 am
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Update: A Walk Through SkyRim

Image


Image


I've been meaning to post a GPS track of my redirected walking for some time now - so here it is. Since I live in Texas, we have football fields everywhere and they make perfect locations for this setup. This represents about 20 minutes of exploration in SkyRim. Walking from Helgen to Hallidir's Cairn - maybe a couple of kilometers in real-world and game-world. I killed a wolf and 3 bandits along the way. There's nothing really new here from my last post but I hope it gives an idea of how the system works. Mostly the guidance is imperceptible. You can see a few places where I got close to the edge and the system pushed me away from it. I got pretty close to the southern goal post at one point before the system thankfully guided me away. The steering is noticeable at those points but just for a few moments. There is also one spot on the left side where I actually did cross out of bounds which is why it's great to have a running track around the field so you can feel the physical boundary with your feet. For the vast majority of time however, you cannot tell that you are being guided and the system does a great job of keeping you in bounds. I play at night in pitch black and have learned to trust the system and let myself become completely involved in the environment - an amazing sensation :D . When I take off my HMD, I have absolutely no idea where I am on the field. So this backs up the academic research that I have read. It takes about a 150 x 150 ft (50x50m) area to implement redirected walking well.

I have been doing a lot of other stuff with this project but I can't give too many details. Mostly I have been optimizing/testing/and replacing pieces of hardware to help improve the performance and usability of the system. Everything from sensors, to displays (ST1080), to physical wiring, to tracking algorithms. A LOT has changed from my initial design plans at the beginning of this thread, but it's all starting to come together (slowly but surely).

I REALLY want to get this in some other peoples' hands soon, but it's just not ready at this point to let out of the lab into the wild. My plan is still to release a commercial version of the system sometime early next year. The project has been re-christened as Red Rovr and I have a blank website up in anticipation of that.
http://www.red-rovr.com/

However I want to have some sort of beta this year, and since I think this product could complement the Rift so well, I am considering having a freeware/demo version first that is customized and hard-coded specifically for the Rift and a single game - SkyRim being the likely candidate. Now there's still some crucial pieces of hardware that the user would have to provide (backtop, sensors, etc). But the software would be free and the cost of the hardware is not very high. I just think it would be so cool to have that one killer demo that you could Wow your friends with. Doom 3 BFG is going to be insanely cool, but being able to physically explore SkyRim with the Rift will just be completely over-the-top (I hope).


Last edited by brantlew on Fri Jul 20, 2012 9:23 am, edited 1 time in total.



Thu Jul 19, 2012 11:43 pm
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Ok... that's cool!
I'd still love to have time to create my VR shoes, but this is looking like a better and better alternative.


Fri Jul 20, 2012 6:02 am
Sharp Eyed Eagle!
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Great work Brant! For the moment, I assume that you are spoofing keyboard input to get it working with Skyrim. In the future, will your software have an interface to the actual position data, for those of us who want to make stand-alone demos?


Fri Jul 20, 2012 8:09 am
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@FingerFlinger: That was the intent - but I'm not sure if the first versions will allow that. It also depends on the quality of the signals that I can get out of it. Directional accuracy is one of my biggest problems so limiting it to only 8 directions masks a lot of those errors. In the coming months I want to experiment with swapping the mouse/keyboard interface for the XBox 360 gamepad interface. The gamepad interface allows analog direction and speed so I can test how accurate the signals are along those dimensions. Unfortunately this comes at the expense of head-tracking accuracy because gamepads only model angular velocity instead of anglular position. I am really curious to see what's more important for realism. Accurate motion simulation or accurate head simulation. I suspect the latter which means that keyboard/mouse would be the default. And of course that also makes it compatible with every FPS since Quake 1.


Fri Jul 20, 2012 8:37 am
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Great work, brantlew! Very interesting ideas and implementation. I will follow this closely from now on. ;)


Fri Jul 20, 2012 10:31 am
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Very impressive. Looks like the system is working pretty good.

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Fri Jul 20, 2012 12:50 pm
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brantlew wrote:

I've been meaning to post a GPS track of my redirected walking for some time now - so here it is. Since I live in Texas, we have football fields everywhere and they make perfect locations for this setup. This represents about 20 minutes of exploration in SkyRim. Walking from Helgen to Hallidir's Cairn - maybe a couple of kilometers in real-world and game-world. I killed a wolf and 3 bandits along the way. There's nothing really new here from my last post but I hope it gives an idea of how the system works. Mostly the guidance is imperceptible. You can see a few places where I got close to the edge and the system pushed me away from it. I got pretty close to the southern goal post at one point before the system thankfully guided me away. The steering is noticeable at those points but just for a few moments. There is also one spot on the left side where I actually did cross out of bounds which is why it's great to have a running track around the field so you can feel the physical boundary with your feet. For the vast majority of time however, you cannot tell that you are being guided and the system does a great job of keeping you in bounds. I play at night in pitch black and have learned to trust the system and let myself become completely involved in the environment - an amazing sensation :D . When I take off my HMD, I have absolutely no idea where I am on the field. So this backs up the academic research that I have read. It takes about a 150 x 150 ft (50x50m) area to implement redirected walking well.



My group did some of the academic work on redirected walking and I'm really impressed by your set-up: I haven't seen many people actually try this scale before. I think I gather you are just doing a constant rate of turn whilst moving? There is lots of work, outside VR, on how much constant rotation people can detect and I think the research predicted you would need an area about what you are using for this. However its easy to generate degenerate paths where you would walk out of the tracked space if you had constant rate turning, so you will either need a (virtual) safety net ,or you'll end up with very strong steering in certain situations which could cause discomfort/ You can, however, significantly shrink the space if you are more agressive in steering depending on the acceleration of the head. The basic theory about this was pointed out in Sharif Razzaque's PhD thesis at UNC-CH (where redirected walking was introduced), but I haven't seen much development of this, other than to note that you can significantly up the rate of turn in situations where the head is accelerating (to 10s of degrees per second).

If you release this, I can think of half a dozen colleagues of mine who would get one so they could study human locomotion (and play some games no doubt). How accurate do you think you can push the head-tracking?


Fri Jul 20, 2012 4:06 pm
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@profvr

This is exactly the type of research I want to do with the system once Brant lets us play with it. Do you have any other resources about what specific work has already been done in this field?

One thing I am really curious about is whether it is possible to steer the user toward a particular region of the play area, in order to interact with props or particular terrain, like a staircase or doorway. Towards that end, I will need to develop a quiver of techniques for more aggressively steering the user.


Fri Jul 20, 2012 5:01 pm
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@profvr: Thanks. I read all the academic literature I could find on the subject. A lot of it seems to deal with optimized paths in special situations when the virtual environment is known in advance (ie. 90 degree turns, etc). For the general case, it seems that constant turning is the only viable solution.

I knew about the methods for accelerated turning during head motion. When I was working within basketball court size areas I was planning to implement it that way. But my curiosity and the challenge of it led me to aggressively push the scale of the system instead. Once I was able to achieve football size areas, I just decided to keep the algorithm simple with a constant turning rate. Besides - I saw some potential pitfalls to linking turning rates to head rotation. Since the tension of your neck muscles and shoulders serve as a fixed reference point you would be able to detect that the world was rotating if you turned your head from side to side and back again. In the pathological scenario, you could make the world spin around you by shaking your head back and forth.

At the size and parameters I have now, I only encounter a boundary about once every 6 minutes (give or take). My simple solution is just to amplify the turn and aggressively steer the player back into bounds. It's noticeable but infrequent enough that it barely detracts from the overall experience. And currently there are plenty of other technical glitches that are much more annoying and attention grabbing than boundary enforcement. ;)

How much can I improve the performance of the system? I'm not sure. There is still a good bit of work left to do on the sensor fusion and signal processing algorithms. But, since I am currently just trying to support PC games right now, the game interface itself is a big limiting factor. I don't have to work as hard to support the course granularity of the keyboard and mouse. Later however, I would like to expand the project goals to see if I can achieve finer grain control. Sorry if I am being vague. In a few months I will be able to talk in more detail.


Last edited by brantlew on Sat Jul 21, 2012 12:26 am, edited 1 time in total.



Fri Jul 20, 2012 5:10 pm
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brantlew wrote:
Later however, I would like to expand the project goals to see if I can achieve finer grain control.


Have you thought about finding where Skyrim stores the view angles for the player in memory and directly writing to those locations, or is it the movement that's more of an issue?


Fri Jul 20, 2012 6:16 pm
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One idea I had for hacking analog motion into games designed for keyboards was to strobe the key presses you send into the game at a high frequency, and with a duty cycle that matches the unit vector of the player's motion, then scale it by their speed. So for instance, to achieve a heading of 37 degrees, your duty cycle for the 'Forward' key would be 1, and for the 'Left' key, it would be .75. Then scale that vector by the player's speed.

I never got around to trying it out, and whether or not it would actually work completely depends on how a particular game captures user input.


Last edited by FingerFlinger on Fri Jul 20, 2012 11:38 pm, edited 1 time in total.



Fri Jul 20, 2012 6:50 pm
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Location: Irvine, CA
@Krenzo: It's the motion that's the issue. If I could write directly into a motion vector then that would be cool but I wouldn't even know where to begin to find that. It's not like hacking into the rendering pipeline (ie. TriDef). Those hacks change the viewport but not the character position in the game model.

@FingerFlinger: That's a pretty good idea. I have no idea if it would work or not. It's worth a shot though because it would be pretty easy to implement.


Fri Jul 20, 2012 9:14 pm
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Joined: Sat Dec 22, 2007 3:38 am
Posts: 990
FingerFlinger wrote:
One idea I had for hacking analog motion into games designed for keyboards was to strobe the key presses you send into the game at a high frequency, and with a duty cycle that matches the unit vector of the player's motion, then scale it by their speed. So for instance, to achieve a heading of 37 degrees, your duty cycle for the 'Forward' key would be 1, and for the 'Left' key, it would be .75. Then scale that vector by the player's speed.

I never got around to trying it out, and whether or not it would actually work completely depends on how a particular game captures user input.

I'd be worried about weird effects when you overrun the input buffer. You could also introduce some nasty lag as the buffer fills up faster then it's consumed by the application. It probably depends on how the game uses the inputs from keyboard, since it may only read them once a frame, in which case, the frequency would have to be much slower then the framerate for it to work. I'd love to see the results of any tests though.


Sat Jul 21, 2012 5:05 am
One Eyed Hopeful

Joined: Thu Jun 07, 2012 7:22 am
Posts: 44
@brantlew: I'm sure lots of people would be interested in the control system. I wouldn't worry too much about the shaking the head and returning to the same direction, in our experience this is not a problem if your control feedback is reasonable; you would anyway only apply the accelerated turning during certain frequencies of head turn where the vestibular and visual cues are not sensitive (roughly equal to "looking around" rather than "shaking the head").

Of course there are lots of other interesting control problems such as which direction to steer them to avoid the boundaries. I am not up to date, but turning to steer them through the center of the tracked region is almost certainly not optimal.


Sat Jul 21, 2012 6:17 am
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