Swerva - A few new locomotion concepts

[Simnertia]

Hi All,
I've been working on a few locomotion concepts and have finally decided to go OPEN at the stage I'm at. I think i've now got far more to gain from constructive feedback/criticism from this community then I have to lose in IP for what would ultimately become "easy to copy mechanical devices".
I've added the concepts as a PDF as they're quite lengthy descriptions with a few pics.
My current plan is to complete prototype versions of both Concept A and Concept B. Concept C is trickier and more costly as well. I will hold out on this one until I see how Concept B goes.
I'm interested in any potential collaborators to push any/all of these ideas forward as an open project.
Enjoy !!
Detlev

[MSat]

Looks pretty complex. Good luck with the project, and keep us posted!

[NeoTokyo_Nori]

Who is your intended market for this?

[Simnertia]

Hi Neo,
I'm certain this approach will be more expensive than an Omni or Virtualiser so not targeting first time users. I can foresee that there will be a group of users who will not be satisfied with either and will be looking for further immersive refinements. So target market is professional users with deeper pockets (still nowhere near as expensive as a driven unit) or advanced home users after a better experience.
Cheers,
Detlev

[cadcoke5]

I have not seen anyone do anything with the omni-directional wheels on a system before, so that may be a novel approach. Your initial drawing shows exisint omni-wheels in a fairly large spacing, in relation to the size of the user's shoe. So, I think that would be a problem that needs to be addressed with either designing much smaller omni-wheels, or alternatively having the user wear shoes that help to spread the load out better, sort of like snow-shoes, but certainly smaller than the size of snow shoes. If the omni-wheels were small enough, normal hiking boots may be stiff enough, though you would probably want a smooth sole without the fancy treads and no gap between the heal and sole.

An alternative would be to actually motorize the shoes with omni-wheels. I have seen this done before. I tried to find a link to the one I saw, but have not been able to. However, I did come across this similar project, http://www.vrwalkerproject.com/

A while back I also suggested an addition to the Whiz Disk. Rather than having the user slide their feet across the surface, the idea was to attach cables to their feet, and then to motorize the shoes, by attaching cables to the shoes, and move the feet by pulling on the cables with a motorized wench system. To turn, you would need to have the cable/wench system actually rotate with the user.

But, dispute all my ideas above, I really suspect that the easiest way to make the user feel immersed in the environment is to avoid walking. Rather, perhaps put them in a virtual all-terrain cycle. Or perhaps, have them stand on an imaginary hover platform. If the platform is perhaps the size of a Whiz Disk (sp?), then the user can still crouch, and maneuver a bit.

-Joe Dunfee

[Zoide]

An alternative would be to actually motorize the shoes with omni-wheels. I have seen this done before. I tried to find a link to the one I saw, but have not been able to.

This one?

http://www.newscientist.com/article/dn9 ... B-GdvldX14

[cadcoke5]

Yes, that is the one I recall. I see that the New Scientist article is dated 2006. When I tried to find something more current, nothing came up as far back as 2010, when I searched using the terms "powered shoes" and the name "Hiroo Iwata". But, of course, since it is from a university in Japan, the English search terms may not turn up any more recent research.

But, if this has not become a viable product in the years since 2006, perhaps it just was not a viable technology. Or perhaps, the originators just didn't have the time/money/energy to bring it to a finished product for consumers.

Personally I have always had concerns about the viability of a stationary walking platform, because of the lack of inertia as you start and stop walking (especially running). But, I may be overly concerned about it. Perhaps an analogous situation is when we can get a stereoscopic effect with two images for our eyes using convergence, but omit the changing focus of the lens. Our eyes seem to adjust for that mis-match regarding what the eye is being asked to do. Perhaps something like that will happen with a walking platform for VR. Though, it may take a bit of time to get used to it.

Today I was looking at shoes, and really noticed that many boots have a very stiff sole. Perhaps just widening the sole a bit would provide all the coverage you need for your original powered omni-wheel set-up. And rather than installing many of the omni-wheels, you might make a shaft with the smaller rollers installed along its entire length. But, I don't know if that would be a whole lot cheaper.

There was one other related idea that was on this forum somewhere. They put marble-sized balls in a plate that just had holes large enough for them to freely move. Then, below that was a single conveyor belt that could be rotated in the Yaw orientation. This allowed them to make the balls move an person is about any orientation. It was called the Cybercarpet. It was built by the Intitute for Applied Mechanics and is now located at the Max Planci Institute for Biological Cybernetics. Here is a youtube video.
http://www.youtube.com/watch?v=bdGH3eOuGIM

I am just mentioning all these alternative, but semi-related projects. To me the one above seems the least costly.


-Joe

[Simnertia]

Thanks Joe & Zoide for your thoughts. I too had come across many of these powered versions in the past. I didn't like the idea that they were trying to reactively compensate for your movement, rather than actually "being" the movement.

My setup, whilst it could be used in a powered fashion is actually designed as a passive unit. If you keep the user stationary in the horizontal plane (as per a Cyberith Virtualizer or Virtuix Omni) your foot contact and applied force should actually drive the two sets of shafts and generate a form of inertia. It would then require effort to either change direction or slow down. You could even add flywheels to both sets to modulate the level of inertia based on the mass of the user. You only need to detect the speed and direction of the shaft movement, not control it.

I agree Joe about the spacing of the wheels being a bit wide. I was looking to knock up a prototype based on available wheels and a 50mm diameter mecanum was about as small as I could find. A final unit would benefit from either smaller wheels or intermediate supports (like a captive ball).
I'll be trying to understand how much of the tread area actually needs to keep inertia. Perhaps quite an area of the periphery could just use captive balls. The intent would be to keep the active area small to help reduce system friction with too many wheels etc.

Cheers,
Detlev

[emsman]

You may consider an ODT currently in development as well.
Infinadeck.com