Question about collimated display systems.

Quote:

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Originally Posted by Matt Olieman

Hessel, Thanks for the links. The last link is VERY interesting. :)

Matt Olieman

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I was doing some mathematical calculations (Pythagoras) yestarday to design a frame suitable for my cockpit , and i discovered a big barrier , it's the "huge Space" .. but i think it would be a great way for the design if we all recognized the validity of it ..

I'm not sure if those calculations are correct or not , but they seems so logic .. correct me if I'm wrong ..

well , my Cockpit width is 165 cm ( Sorry for the non-US unit ) , so this is the idea of the calculations :-

1- Forward- Projection screen's radius
- I began by the base of the Forward-Projection screen , I planned to be as width as the cockpit .. plus say 5 cm , so the light rays would be free of hitting the cockpit , because it's the first task to guarantee that all light rays from the Forward-Projection screen would hit the whole of the mirror totally , and after i guarantee that task , i can plan the mirror radius / widths / etc according to those calculations .. See Picture below !

http://www.mycockpit.org/photopost/u...597/Radius.jpg


2 - Mirror's Radius
- After i calculated the Forward-Projection screen's radius , I then calculated the Radius of the Mirror .. The idea is the Screen would be in a distance from the Mirror less than the focal length , So i first assumed the screen would be 20 cm in front of the focal point , so the focal length would be [ screen's radius - 20 cm = 249 - 20 = 229 cm ] , Now I could calculate the Mirror's radius by multiplying the focal length by 2 [ 229 x 2 = 485 cm ] , See Picture below !

http://www.mycockpit.org/photopost/u...597/Mirror.jpg

3- Mirror's Lower ( Bottom ) width
- The triangle of the lower width , it's base would be the Mirror's lower width that we aim to calculate , as we know the total sum of any triangle = 180 degrees , so as the base angle = 40* , so both the other angles = [ 180 - 40 / 2 ] = 70* .... & see the Picture below !!

http://www.mycockpit.org/photopost/u...597/Bottom.jpg


4 - Mirror's Upper width
- see the picture , i guess it's now clear !!

http://www.mycockpit.org/photopost/u...1597/Upper.jpg


Remarks
- The first 30* angle , to draw a latitude of 30 South ( If we looked to the screen as the earth )
- The 2nd 40* angle , because our Field of View ( FoV ) = 40* .. drawing latitude of 70 South .
- The opposite side is the same as above .
- As the half circle = 180 degrees , so the remain angle ( Mirror's Lower width's angle ) would equal [ 180 - {(30* x 2 ) + ( 40* x 2 )} ] ...

Looking forward for your thoughts

Mohammed Sayed

I was doing some mathematical calculations (Pythagoras) yestarday to design a frame suitable for my cockpit , and i discovered a big barrier , it's the "huge Space" .. but i think it would be a great way for the design if we all recognized the validity of it ..

I'm not sure if those calculations are correct or not , but they seems so logic .. correct me if I'm wrong ..

well , my Cockpit width is 165 cm ( Sorry for the non-US unit ) , so this is the idea of the calculations :-

1- Forward- Projection screen's radius
- I began by the base of the Forward-Projection screen , I planned to be as width as the cockpit .. plus say 5 cm , so the light rays would be free of hitting the cockpit , because it's the first task to guarantee that all light rays from the Forward-Projection screen would hit the whole of the mirror totally , and after i guarantee that task , i can plan the mirror radius / widths / etc according to those calculations .. See Picture below !

http://www.mycockpit.org/photopost/u...597/Radius.jpg


2 - Mirror's Radius
- After i calculated the Forward-Projection screen's radius , I then calculated the Radius of the Mirror .. The idea is the Screen would be in a distance from the Mirror less than the focal length , So i first assumed the screen would be 20 cm in front of the focal point , so the focal length would be [ screen's radius - 20 cm = 249 - 20 = 229 cm ] , Now I could calculate the Mirror's radius by multiplying the focal length by 2 [ 229 x 2 = 485 cm ] , See Picture below !

http://www.mycockpit.org/photopost/u...597/Mirror.jpg

3- Mirror's Lower ( Bottom ) width
- The triangle of the lower width , it's base would be the Mirror's lower width that we aim to calculate , as we know the total sum of any triangle = 180 degrees , so as the base angle = 40* , so both the other angles = [ 180 - 40 / 2 ] = 70* .... & see the Picture below !!

http://www.mycockpit.org/photopost/u...597/Bottom.jpg


4 - Mirror's Upper width
- see the picture , i guess it's now clear !!

http://www.mycockpit.org/photopost/u...1717/Upper.jpg

Remarks
- The first 30* angle , to draw a latitude of 30 South ( If we looked to the screen as the earth )
- The 2nd 40* angle , because our Field of View ( FoV ) = 40* .. drawing latitude of 70 South .
- The opposite side is the same as above .
- As the half circle = 180 degrees , so the remain angle ( Mirror's Lower width's angle ) would equal [ 180 - {(30* x 2 ) + ( 40* x 2 )} ] ...

-- Those calculations for explanation only , but of course as the upper curve’s latitude increases , the radius increases ….

Looking forward for your thoughts

Mohammed Sayed

Hello, i read this thread all - cool! I have question:

how did you control vertical mirror radius and horizontal mirror radius ? I construct analog your system, but i can't make vertical radius equal horizontal radius =(

how did you control sphericity?

thanx!

http://www.mycockpit.org/forums/atta...0&d=1298884381

http://www.mycockpit.org/forums/atta...1&d=1298884381

http://www.mycockpit.org/forums/atta...2&d=1298884381

http://www.mycockpit.org/forums/atta...1&d=1299057594

The design geometry is defined by the frame shape, which must lie entirely on the surface of the sphere. When the mylar is first installed, it will have the shape of a cone, and will deform into the spherical shape when the proper vacuum is applied. Until the vacuum is at the right level, the horizontal curvature will be larger than the vertical curvature.

How have you attached the mylar to the frame? Is it just clamped in place? If so, the extra material on the edges may stretch inward unevenly, creating an unacceptable amount of distortion.

For the prototype, we know the vacuum is correct when the mylar makes contact with the internal ribs. Once we see the distortion from the ribs (clearly visible in the photo on page 13, post#128), we reduce the vacuum just until the distortion disappears. For the full-size version, the ribs have been set back, and will not touch the mirror. Instead, we've developed an optical sensor based feedback system controlling a valve box to keep the mirror in the correct position. We'll need to install a temporary "indicator block" on one of the ribs to find the correct sensor reading when the mirror is in position, but once we've established that value, the indicator block will be removed.

We attached mylar to the frame without adhesive tape or glue.
Only still strip.
It is no good - we understand now =)

So well, we have two different problem: distortion and sphericity.

I just found some great photos - they appear to be of the same CAE sim installation shown in the earlier video.

http://www.fotothing.com/B0B/photo/4...989d52150212c/

Quote:

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Originally Posted by wledzian

I just found some great photos - they appear to be of the same CAE sim installation shown in the earlier video.

http://www.fotothing.com/B0B/photo/4...989d52150212c/

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You know Wayne, looking at some closeups of those photos (TY BTW-great hi res pics!) I would almost swear, that the mylar absolutely gets stretched across the back surface of the frame when it's under vaccum. There doesn't appear to be much of a cavity for the mylar to to be drawn into, as opposed to your original prototype. (speaking of which I'm awaiting anxiously to see new pics your current iteration )

Seeing it up close in those hi res photos, make my brain think that it makes perfect sense for the mylar to actually be drawn onto a surface, rather it being suspended in a void. In one of the pics, I can judge no more than maybe 2 inches of the relaxed mylar from the back surface of the frame. I could be wrong, and I probably am, and I'm OKAY with that lol. But after seeing those photos, I just can't help thinking it is so. EDIT

Hi-

Thought I'd chime in here.

The mylar material needs to be optically near perfect as it is becoming a lens. Having a surface "push through" would distort the image.

Think of a mylar balloon, forgetting the wrinkles near the edges, the surface is perfectly smooth and so too is the CAE flight simulators as per these photos. The vacume pulls the mylar, or rather the pressure differential allows the mylar to " ballon" out from the rail frames that drape the material.

There's not much of a cavity behind the mylar, but the mylar touches only the frame. The structure is spherical as well, probably only larger than the mirror by a couple of inches as you said. As mikesblack mentions, contact with the back surface would produce optical distortion.

The stretched mirror forms what is essentially a big drum head. With mirrors that large, the 'drum' can vibrate at a frequency which produces visible effects. One design goal is to minimize the space behind the mirror, in order to keep the resonant frequency as high as possible. With our prototype (and we hope, with the larger version as well), the mirror is too small to resonate at such low frequencies, so the large cavity is not a problem.

In other news, design work is all but finished, the frame and table parts are all cut. We need to polish some details on the screen design, but the remaining work there is little. I've got other business keeping me from the sim this weekend, but I expect we'll begin assembly on the 19th.

Hi Wayne,

How wide, radius and degrees vertical and horizontal will the final mirror be?

Given that material can be found at 55 inches, could you remind me what limits we face and in my case assuming a 7 foot radius curve and 40 degrees vertical( ideal).

I have been thinking about using either thin plasic packaging tape or mylar tape to join 2 sheets of mylar. I have experimented with small pieces and have found good results. The tape is applied on the back of both pieces and carefully lined up and smoothed on.

Love to hear your thoughts on that.

Hope you and Gene are well.

mikesblack: I suspect that when you try to stretch the mylar under vacuum that it's going to distort at the seams.

The current setup gives us an 8' diameter mirror. The framework provides 180 "real" degrees of mirror plus the extra we get for the "ears". If I remember correctly, this gives us 180 degress of "perfect" view with some space on either end that provides "usable" mirror which then degrades into "funhouse mirror" at the ends.

If you look at this picture: http://www.fotothing.com/photos/492/...50212c_ab4.jpg you'll see the "ear" that we keep referring to. On their setup, they've trimmed the mylar back from the full curve of the ear. Our mirror will cover it completely because of how we're attaching it.

The photo that really got my attention was this one:
http://www.fotothing.com/photos/115/...c9a914_9f6.jpg
If you zoom in on it you can see that the mylar is being brought into position in a fashion very similar to how a shower curtain is hung. You can also see two black parallel lines at the top edge of the mylar. This makes me wonder if there's something sewn into the material - maybe a reinforcing strip or something like a sail bat?

I suspect that band is some kind of reinforcement for the method they're using to hold the mylar in place. I'd love to talk to the guy on the ladder. :)

That image shows some of very interesting details - one an approximate depth of the frame. You can see it in the bottom right hand corner of the image. Another detail is what appears to be the vacuum port at the back of the framework in the center. I'm not sure why there is two - volume maybe?

In the lower LEFT corner, you can see what looks suspiciously like the paper that would cover double-sided tape! It looks like the repeating logo thing done on some brands of 3M tape. The tan color above it may also be some kind of tape backing. If you look closely, you'll see a "hump" in the material (right near the left edge of the image). I've seen a similar effect in double-sided tape backing when it's applied around a curve... I bet if we could see the "ear" on that end, there would be a line of that material going straight up to the top edge of the framework.

In this image:
http://www.fotothing.com/photos/88d/...c2e7fd_15d.jpg

...HA! I was right! If you look at the bottom of the image, just to the right of the ladder, you can see a bit of adhesive covering peeking from behind the mylar and directly to the right of that there is an obvious band where the mylar is stuck to the tape! I don't see any evidence of the reinforcement band on the bottom, so that may have only been done in order to lay the mirror in place before they expose the adhesive behind it. In fact, if you look to the top of the mirror directly above the band I just mentioned, you can see extra material folding forward of a line that appears to have attached it - I think at this point in the process the worker is working from right to left - you can see how the mylar is "stiffer" on the area on his right. He's in transit on the ladder by the position of his foot, but I don't know if that's going up or down. :D The area to his left is still being supported by the top edge, so there may be some kind of rail up there that we can't see - maybe for removable clips that are attached to that reinforcing band?

This weekend I'm going to try to get the base platform built and painted. This is what the table will attach to and then the mirror chassis will attach to the table.

We're going to build a new screen - more in line with the current design. The trick is going to be building a jig in order to cut the foam with. I don't expect it to be much of a problem though. Anything that keeps my fingers way from that table saw blade makes me happy. The last one we built was something like 40+ cuts on the table saw with the blade run all the way up and my fingers about an inch away from it. I was really, really glad to be done with that particular part of the project. I had to be lucky every single time. The table saw only has to be lucky once. :)

g.

I just did a bit of research on the CAE 7000 Series simulator that those pictures show - it has a FOV of 200 degrees wide by 43 degrees high. The mirror that Wayne & I are building is really close to that 180-190 (or so) wide and 40 high. Not too shabby for a couple of sim geeks. :D

g.

Mike,
Without digging into interference issues between cockpit and display geometry, I can squeeze about 115° out of the full-height mirror, with possibly an additional 10°-15° usable in each ear, using a 1" margin. This does not account for the dead band, which probably eats up about 5° at the top and bottom, leaving ~30° usable. If I increase the vertical FOV to give a 40° usable area, the full-height section drops all the way to 30° horizontal, perhaps 70° total including the ears.

Thank you Gene and Wayne. Appreciate the response.

What do you guys think of my idea for joining mylar in order to get full width?

The seam will be locally stronger, and will therefore stretch less. This will most likely produce some fairly severe distortion.

I was thinking the same thing, but figure it may be worth the experiment. I'll let you know what I find.

BTW Do you know who manufactures the mylar for CAE and the other sim manufacturers?

Hello all.

I was talking to a friend who visited the install of one of these. He says that the back of the dome is a material like felt or fine carpet which is either attached to a solid structure or has been treated to be stiff enough on the back to hold the spherical form. Because its carpet/felt it isnt air tight and allows air to be drawn through it. Looking at the pictures I think he might be correct, it certaintly looks like it has hand prints in it like you would find on the top of a pool or snooker table. He didnt mention how the mylar was attached to it but I think we can see it in the pictures and figure it out.

Please look closely at this photo http://www.fotothing.com/photos/115/...c9a914_9f6.jpg that Gene also linked to.

Around the top and bottom of the black dome area where the mylar gets attached if you allow your eyes to follow it around the curve I believe it is sloped backwards from the black dome. Some of the patents linked earlier in the thread (if memory serves, perhaps they were on one of Mike's tutorials) showed methods for attaching the mylar. One showed the use of material to for a uniform curve around the top and bottom of the mirror so that the mylar isnt going around a sharp angle and this makes sense with the picture's sloped back attachment area.

So contrary to Gene I think the material is folded back and not forward in the second picture.
http://www.fotothing.com/photos/88d/...c2e7fd_15d.jpg
I also think he might be working out from the centre to the sides.

So my interpretation is this. The mylar is placed in the dome shape. Note that there is no measuring equipment visible in any of the photos (tape measures etc) so the black lines on the top must make sure the mylar is positioned correctly. As the guy moves out from the centre he removes a bit of the backing paper from the tape (as can be seen at the bottom in the second picture, there is a tail of the brown backing paper peeking out from under the mylar) and he sticks it down on using the black marks for guidance. The thing I cant figure out is how he knows where to stick the bottom, there are no black marks that I can see, surely it has to be more scientific than just guessing when the mylar is loose enough.

In the second picture at the very top right you can see the black marks for the top but on it's back there is no evidence of reinforcement.

Anyone have any thoughts?

Tom

I'm not sure of the exact supplier (it was 10+ yrs since I was playing with Mylar) but I do recall the manufacturer was in Eastern Europe (narrows it down slightly) and material had to be purchased by the tonne/ton or 500m +. Basically a complete roll. Even when working for a large sim company, the dollars were large.

For those currently building with Mylar, there were a few occasions when people had dropped screw drivers from the top of the screen ..... followed by a big POP and a large OH **** and then a few more OH ****'s.

The developments forward in this area is truly amazing.

Hopefully helpful:
http://www.rockwellcollins.com/~/med...a%20sheet.aspx

Especially with the vacuum considered, even a screw might have unwanted effects (read return to square one) on the "mirror".

http://www.youtube.com/watch?v=Wqq4-XC5f8U - You see this!?

http://www.youtube.com/watch?v=Wqq4-XC5f8U - You saw it?

hi everybody ..
i've been trying to keep up with new stuff , and found my self reading the whole thread .. this is the most interesting topic of all :)
i made a solidworks prototype based on some hypo dimentions ..
Attachment 5088

wledzian, geneb,
It's been a couple months now since your last post, how is the wide mirror doing?
Hope you are continuing with your fantastic success :-)

regards,
Ethan

Sorry guys - take a peek at these videos:

http://www.youtube.com/watch?v=j3FvFx9z2R8
http://www.youtube.com/watch?v=Bx5eb5yTDQw
http://www.youtube.com/watch?v=_cyJIGII6JE

The display system is essentially completed. The vacuum controller has been rebuilt and is working perfectly. The last "construction" that needs to be done involves building a cardboard "blackout cap" to enclose the display.

g.

Really amazing guys. I wish I'd been as resourceful 5 years ago when I was trying very hard to come up with a wide visual.

Could you post the mechanical dimensions of your mirror frame please?
Also, I wonder if you can see the front projection screen in night scenery? (since it's white, does it reflect ambient light?)

It does reflect ambient light, but the entire assembly will eventually be capped. Ambient light shouldn't be an issue.

I was thinking that even when it's fully enclosed, the few bright dots of light that are projected onto the screen at night might stray around enough to cause enough ambient light to make the screen body visible. A Sim engineer I talked to once told me thats one of the reasons that usually back projection is used. Not that that would stop me wanting one :-) I light daylight scenes better anyway!

rear-projection also has its problems - light from any point on the back side can spill light on the rest of the screen, reducing contrast. The problems you mention are just as much of an issue on first-surface projection as well.

Hello

I'm glad I found this thread. I find this topic fascinating and am working to improve my understanding of the optics involved.

Following wlzedian's earlier post (ex. #58 ), I developed an excel spreadsheet to calculate points on a surface screen for a hypothetical collimated display. Using the resultant points, I am able to develop a very close fitting ellipsoid (major axis is horizontal, center is same as mirror, rotation axis is vertical also through center of sphere).

What I get are parameters (a,b) for the ellipse as shown here

http://www.flickr.com/photos/alfredetlaura/6032314024/

What puzzles me now is:
From the (pilot's) eyepoint, how much vertical and horizontal movement still provides an image reasonably free of distortion? In other words, how can I assess what I will see as my head moves from sided to side, or up and down? Any distortion?


Mike.Powell writes (post #78 ) something I do not understand:
"Once you have a workable configuration, you can ray trace diverging paths from multiple points on the screen surface to check for collimation accuracy."

I'm not sure how to go about doing this 'in 3D'. I can hardly immagine doing these calculations manually. I am under the impression that to answer this question, 3D ray tracing is probably required, but I'm at a loss as to how to go about doing this. I am not familiar with TurboCad.

Any pointers are well appreciated!

Ron,


On a side note:
In astronomical telescope design, a similar problem arises with the so-called tilted component scopes, such as the Schiefspiegler; with these scopes, there are two spheric reflecting surfaces tilted with respect to one another. In telescope design in general, ray traces and spot diagrams are done for two perpendicular planes: the tangential and the sagittal planes. This is well explained in Telescope Optics - Evaluation & Design, Rutten & Venrooij, Wilmann-Bell, 1988.

I'm left wondering if methods used in evaluating tilted component telescope design can be used in collimated displays.

Hello

I'm glad I found this thread. I find this topic fascinating and am working to improve my understanding of the optics involved.

Following wlzedian's earlier post (ex. #58 ), I developed an excel spreadsheet to calculate points on a surface screen for a hypothetical collimated display. Using the resultant points, I am able to develop a very close fitting ellipsoid (major axis is horizontal, center is same as mirror, rotation axis is vertical also through center of sphere).

What I get are parameters (a,b) for the ellipse as shown here

http://www.flickr.com/photos/alfredetlaura/6032314024/

What puzzles me now is:
From the (pilot's) eyepoint, how much vertical and horizontal movement still provides an image reasonably free of distortion? In other words, how can I assess what I will see as my head moves from sided to side, or up and down? Any distortion?


Mike.Powell writes (post #78 ) something I do not understand:
"Once you have a workable configuration, you can ray trace diverging paths from multiple points on the screen surface to check for collimation accuracy."

I'm not sure how to go about doing this 'in 3D'. I can hardly immagine doing these calculations manually. I am under the impression that to answer this question, 3D ray tracing is probably required, but I'm at a loss as to how to go about doing this. I am not familiar with TurboCad.

Any pointers are well appreciated!

Ron,


On a side note:
In astronomical telescope design, a similar problem arises with the so-called tilted component scopes, such as the Schiefspiegler; with these scopes, there are two spheric reflecting surfaces tilted with respect to one another. In telescope design in general, ray traces and spot diagrams are done for two perpendicular planes: the tangential and the sagittal planes. This is well explained in Telescope Optics - Evaluation & Design, Rutten & Venrooij, Wilmann-Bell, 1988.

I'm left wondering if methods used in evaluating tilted component telescope design can be used in collimated displays.

Well as a person that didn't know anything about collimated display systems until yesterday let me say I'm all excited and the Mrs has given me the go ahead to build one, so long as it's a two person set-up. Here are a few dumb questions and cross referencing from different industries.

1) Does the mirror have to be 100% reflective? Of course you want the best you can afford; but where is the middle ground? My first projector used a white wall and then a bed sheet, so I can accept a lot of imperfections along the way.
I've been following this guy who tries a lot of diy mirror configurations for solar power and he as made a few nice looking easy(ish) to make parabolic mirrors. As we only want a portion of the mirror it looks feasible. http://www.youtube.com/watch?v=St-0HWKAY4k
http://www.youtube.com/watch?v=MYC7HyKbkpI

1b) As they do with telescope mirrors . If you attached a lot of control points on the back of a steel mirror could you pull it into the shape you wanted and correct and fine tune the image digitally. I've been looking at a lot of Johnny Chung Lee work and this could be set up to auto correct the image you want to see. http://johnnylee.net/projects/thesis/

Getting rid of the huge mirror idea. I understand why don't you project on to a white screen as it helps the illusion to bounce one image off another S0 -
2) It is possible to use a projector to project on to a mirror and have that image bounce of a white background into the eye? I just thought you could inflate a mylar balloon easier. I guess the balloon could be over sized and the holding frame would make the mylar bulge and deform where needed. You could even inflate the ballon to full a much easier to make acrylic former.

Just my ideas. Are there any CAD plans for building this. I haven't understood the maths to make one yet.

I've also though about using corian as a surface to project on to OR apply a mirror finish to.

Thanks for a good weekend of reading.

Hello,
Im very new to everything. I guess you can call me a (newbe). I need help on getting my game to work. I have eyefinity six video card and tryinbg to run six monitors. If can give any advise please let me know.

Thanks!!!
Papa#1

Papa #1 ....

A couple of google search links to start you off ....

http://www.tomshardware.com/forum/27...heck-eyefinity

http://www.devhardware.com/forums/at...ty-310385.html

http://forums.whirlpool.net.au/archive/1469262

There is a load more on the web and I recommend some surfing and reading ......

It's kinda difficult to help when the problem is such a broad one. Exactly what problems have you encountered so far. Like, do you need help with physical installation or with configuration after your physically connected in the new card.

Try being a little more specific in the help you need and typcially someone on here will offer.

Also, this is a thread that is about Collimated Displays so it may be appropriate to start your own thread for your question !!!

Good luck
rgds

Thank you for the message. I will see if any of these may be helpful to work with. My can turn on the game just fine. It will let me up until the point I go to fly. Then the screens all go black then start flasking. The game will then shut itself down. I can't figure out why? Any suggestions?

Quote:

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Originally Posted by theother5

Papa #1 ....

A couple of google search links to start you off ....

http://www.tomshardware.com/forum/27...heck-eyefinity

http://www.devhardware.com/forums/at...ty-310385.html

http://forums.whirlpool.net.au/archive/1469262

There is a load more on the web and I recommend some surfing and reading ......

It's kinda difficult to help when the problem is such a broad one. Exactly what problems have you encountered so far. Like, do you need help with physical installation or with configuration after your physically connected in the new card.

Try being a little more specific in the help you need and typcially someone on here will offer.

Also, this is a thread that is about Collimated Displays so it may be appropriate to start your own thread for your question !!!

Good luck
rgds

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I've read this thread now about 3 times, and am totally fascinated. It's incredibly impressive and I'm seriously thinking about taking it on myself. But the thread died abruptly last year. Wayne and Gene, did you get done and now are having too much fun? Any updates? Lessons learned?

Thanks,

Salire

Salire, if you head over to http://www.youtube.com/f15sim, you can see the most recent videos that we've done on the project.

More exciting news will likely be posted this coming weekend. :)

g.

Thanks, Gene. Yes, I've seen all your videos, read your site, downloaded the patents, etc. The size of your rig looks doable for the space I have available (first time I've ever had a rumpus room and I want to take advantage of it). So before I start on something I'd sure love to be able to stand on your shoulders and learn from the experience.

I'm curious, too, about your personal assessment on the marginal benefit (in terms of immersive experience) of having the collimated view over a simpler wrap-around direct projection (dome or cylinder)?

Sal

The benefit of collimated vs a direct projected screen is HUGE. You get a sense of depth that simply isn't possible with a "normal" projected screen. The visual cues you get are as close as possible to reality - this is why the FAA mandates collimated displays for Full Flight Simulators.

Wayne can tell you much more about how he experiences the visuals than I can - I don't have binocular vision (my eyes don't work together, they work individually, so I have no "built-in" depth perception).

You should keep in mind that the display project we've built is really only suitable for a single seat cockpit - it's not large enough to do a proper two place cockpit, even a small one like a Cessna 152.

g.

Thanks.
re: Single seat: Yes, that's one reason I'm so attracted to the scale of your project. I'm planning a single seat GA configuration with a glass cockpit. The first try is going to be X-Plane with a FlyThisSim G1000 avionics emulation controlled by an ACER 24" touch screen, and the CH products HOTAS control suite. I'm basically going for state of the art high performance GA VLJ or Cirrus type design, but generic. I want a realistic flying experience, but I'm not driven to make it a replica of anything. In fact, I enjoy playing with the ergonomic design aspects. The OTW experience is a big deal to me, so I'm really wanting to do something that delivers. Sounds like the size of what you guys did is perfect for my application. Once I get the OTW display set, then I would build the cockpit accordingly to make the pilot view fit with the display limits.

S