Glass Mountain Optics / FlightSafety Intl.

Hello,

I'm the proud owner of the following. You guys have any idea of what it may be worth?

C-20 S
The C-20 collimator is designed to offer the entertainment industry a simulation grade display system providing the highest level of performance. The wide angle C-20 S allows ample head motion and fields of view for most entertainment applications.

The C-20 system includes several advanced technologies designed to provide maximum performance and minimum maintenance. Each system includes a fully adjustable mirror, beamsplitter and monitor to ensure proper component alignment. Our uniquely designed swing out mirror allows for simple routine maintenance and offers complete access to all major components while maintaining precise optical alignment.

Each C-20 collimator system includes:

• High resolution monitor
• Commercial grade collimating mirror
• Commercial grade beamsplitter
• Self-contained, motion compatible housing
• Complete assembly and alignment at the factory, ready for immediate installation

Major features include:

• Swing out mirror for access to all major components
• Minimal maintenance requirements allow for maximum utilization
• Multisync monitor will accept most video signals
• Images appear focused at infinity for greater realism
• Ruggedized system is fully motion compatible

Entertainment Experience:

• Engineering support for 250 Virtual World Tesla BattleTech cockpits
• Marty Arrant at Applied Emerging Technologies, Inc. (AETI)
• Kinney Aero at Fighter Town USA
• Bandit Country
• Optics design consulting and services for Redifun Simulation

How much did you buy it for? :)

You mention FlightSafety, but it sounds like this is a system for the entertainment industry?

As you may know, the old beamsplitter systems have been largely abandoned by the simulation industry in favor of seamless curved mirrors with rear-projection screens above the cockpit. These are vastly superior. Having said that, I'd imagine the old beamsplitter systems have some nice advantages when space is limited, or when you want something is that (slightly) more portable and less maintenance-intensive. This system was probably quite pricey when new. Sadly, these nice components tend to not be worth much on the open market. I have a rear-projection spherical screen from FlightSafety that I'm told cost them around $50k to have built. It has become very slightly tinted after years of sitting in front of CRT projectors (though not enough to make any significant difference when used with nice bright modern DLP projectors). Now, I'd be lucky to get ANY amount of money for it.

Having said all that, I'm sure most of us here (including me) would LOVE to get our hands on a beamsplitter setup and do some experiments with it. A beamsplitter rig will provide a relatively narrow, flat viewing area, but should give you a great sense of depth, as well as some decent parallax effect. How about firing it up and taking some pics?

Matt

I'll do just that and post them.
Thanks Matt.

I fired it up and here's a few photos.
http://www.mycockpit.org/forums/atta...id=11332&stc=1
http://www.mycockpit.org/forums/atta...id=11333&stc=1
http://www.mycockpit.org/forums/atta...id=11334&stc=1
http://www.mycockpit.org/forums/atta...id=11335&stc=1
http://www.mycockpit.org/forums/atta...id=11336&stc=1

See Photos below,
Thanks,
Randy

That looks sweet, thanks for sharing! I'm curious as to how it's intended to be mounted, however....seems like that lower chassis would be in the way of cockpit structure. So, you gonna build a cool sim out of it? :)

Glass Mountain was acquired by Flight Safety. They still have the same people working there after all these years.
They recently told me that:
The C-20 kit designed for use with a 20” monitor. It used a 40” radius concave first surface collimating mirror and entertainment grade beamsplitter.
When the floorspace footprint doesn't matter, the other mirrors are probably the choice.
Realize, this entire cockpit had a footprint of 3.5' x 7.5' including a forward cabinet for a computer server, large AC Isolation transformer, large DC power-supplies, and Audio amplifiers. Spacious room for the tech to service. Then, the seat held large, tall customers. No cramped quarters.

Frame is well constructed. In a busy location or convention, these ran 7 minute "missions" in network mode. That was general public 6 pilots an hour for a long weekend.

At least at the time, it is thought that the entertainment grade beamsplitter was made on the same assembly line. Having worked at Texas Instruments decades ago as the final AT Engineer, we know that often the same produces come of the assembly line. They differ by the cost and or testing of validating the specifications.
While specifications might prevent these from being used to supply a GSA contract, they are in fact just awesome for other uses.
The difference between looking at a projector image, or a large screen vs beamsplitter image with something in motion is a great experience.

I own 12 of these. Wouldn't mind finding a group of people who could team to produce a modern version of some flight sim. But, it appears more and more the beamsplitter / concave mirrors are finding their way outside the old simulator design.

Hi Tesla, that's very interesting info about Glass Mountain. I didn't realize FSI still had anything to do with these older beamsplitter-based devices.

I have a big honkin' Fresnel lens from a commercial-grade flight training device (a retired AST-300 from a flight school). It's noticeably better than the dinky overhead projector lense and similar types I've tried over the years. Like the beamsplitter, as you said, there is simply no comparison between this and even a large, high-quality flat projection system. What I'm not quite sure of is how this lens compares to a beamsplitter unit like the Glass Mountain rig. I asked on a flight sim tech forum a while back, and one of the guys there (who works on "big sims") insisted that using just a Fresnel lens did not collimate the image or change its focal point. Of course, I can tell first-hand that it most certainly DOES focus the image out quite a ways, and effectively enlarges the image as well. If the beamsplitter approach doesn't give any advantage over the better Fresnel lenses, then there's no point in me researching them further. I've only "flown" with a beamsplitter system once, it was on an older Lear 35 sim with night-only graphics, and it was 17 years ago. I really can't compare it very well to what I've been doing with my sims the last couple years.

The sims sound interesting, do you have any pics? Still using them? Going to sell any of the visual systems? :)

Matt

There are more than one type of Fresnell lens setups. At the risk of sounding like a consultant, my guess would be that "it depends".
:-P
In theory a Fresnell sounds good.
A mirror has other plus and minus. It is often still used for high-quality optics.
The other point is the small footprint. One of the nice projection systems I was lucky to experience was at Kings Point (USMMA.EDU).
This is a full ship simulator. You can even go out on the front of the and ring the bell. The projector screens are still massive and far away. When they simulate a near miss of a cargo ship, it is scary to be able to read the numbers on the cargo crates of the other virtual ship! While the sim is slower moving there are still a lot of physics including the windowless engine room simulator several floors down.
Now this foot print is ... well massive of course.
The beam splitters on the sims here are tiny as far as the floor foot print. The sims are hauled to conventions and other places.
The photos above came out of these kind of units.
There are 12 in this photo. The forward doors hold all the PC (server), DC power supplies, audio amp, and even a large AC isolation transformer plus the custom circuits that manage the serial connections to the multiple displays (6 in all with over 8 buttons each).
Then the Beam Splitter is between the sliding door and the forward door. The cockpit is actually roomy. There are some large (tall) people with long legs who can fit in. The plastic cockpit shell with its multiple surround sound speakers is acoustically great! There are many circulation fans for both the cockpit area and the electronics Basically it not only cools, but helps with the dust management.
The entire footprint is 3.5' wide, 7.5 long and 7.5 tall. In the day, the 20" CRT (facing down from the top) needed to be higher. The younger ones don't remember the CRT Yoke (not joke, yoke LOL).
A couple of them were replaced with newer LED. M guess is that the newer OLED would be... very wonderful.
That is a lot of self contained sims in a small area.
Granted, this is only a single pilot. Its not a multi-seat unit. However, the fantastic effect of the beamsplitter and concave mirror with a small footprint in a unit on wheels weight about 550 pounds has its advantages.

Hi Matt,

Any idea where one would be able to purchase fresnel lenses? I would like to experiment with my setup. Limited space so wrap around screen is out of the question, so if I could compensate with depth cues with the front projector/monitor that would be great.

Thanks.

Ben

These guys quoted me, a while back, US$200 for a new Fresnel from the AST-300, or US$100 for a used one:

http://customsimulation.com/

Tesla, those seem like pretty slick sims. I'd love to see the interior. :) Switching them to OLED might be worthwhile. A friend of mine got his hands on a level A Learjet 20-series sim with an early VITAL system (concave mirrors and beamsplitters). Disappointingly, he reported terrible performance when attempting to use this system with LCD monitors. I can't really imagine why. I'd love to try it with flat projection as the image source, myself.

My setup is relatively compact. My projector is above the pilot's head (very close to where the back-projection screen would mount on a modern commercial sim), which is beamed onto a flat screen in front of the pilot. That screen is mounted at about the same angle as a typical aircraft windshield (lots of keystone correction required). Then, my AST-300 Fresnel sits in front of the pilot at almost the same angle (looks like a windshield). The effect is fabulous. My biggest problem is getting this to scale up to more than one channel, and figuring out juxtaposition with the rectangular lens shape (the Glass Mountain unit appears to have a slight trapezoidal shape, making it better suited to juxtaposing with other units).

I had almost settled on doing a large cylindrical screen for my Sabreliner project, until I started flying with the Fresnel. Now I'm on the lookout for more creative, collimated solutions. Gene Buckle has worked out a fabulous collimated system with a spherical mirror (made of Mylar), but it requires a lot of space, as well as extremely precise construction and placement. Ideally, I'll end up with something that is relatively portable.

Matt

Great, thanks Matt. I will inquire -- any photos on your setup? :)

The other thing to consider is laser projectors -- the sony pico projector CL1A has ?infinite focus -- the image stays in focus even on a curve screen. Perhaps that could work with a collimated setup. Unfortunately the sony pico projector doesn't meet the lumen or short throw requirements for a home cockpit :(

I'm actually working on the sim a bunch this week, will snap a few pics of the display rig next time I get it fired up.

The laser projectors are interesting, but need to mature before they're really ready for our sims. I am interested in calligraphic displays to augment my current projector setup, but there seems to be no development on that front for consumer/hobby-grade uses (despite the fact that the "big boys" have been using them for years). I'd imagine it's quite difficult and expensive to do.

Matt

https://www.cnet.com/news/led-lcd-vs-oled/
The first substitute of a 19" LED (around $280 about 11 years ago was blurry on movement.
Since then, things have improved every year. One of my 3D systems is 240 HZ so shutter glasses provide 60 hz each L/R for two people viewing different 3D content.
The design of the cockpit shell with a sliding curved door provides both sound and light conditions that add to the experience.

What is better, a 40" Mirror or a 34"x44" Fresnel lens to gather solar energy? As it relates to Simulators:
The Fresnel lens (<nobr aria-hidden="true">area=34×44=1496..in 2 </nobr><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>a</mi><mi>r</mi><mi>e</mi><mi>a</mi><mo>=</mo><mn>34</mn><mo>×</mo><mn>44</mn><mo>=</mo><mn>1496..</mn><mi>i</mi><msup><mi>n</mi><mn>2</mn></msup></math>) might appear to be better than the parabolic mirror (<nobr aria-hidden="true">area=π(402 ) 2 =1257..in 2 </nobr><math xmlns="http://www.w3.org/1998/Math/MathML"><mi>a</mi><mi>r</mi><mi>e</mi><mi>a</mi><mo>=</mo><mi>π</mi><mo stretchy="false">(</mo><mrow class="MJX-TeXAtom-ORD"><mfrac><mrow class="MJX-TeXAtom-ORD"><mn>40</mn></mrow><mn>2</mn></mfrac></mrow><msup><mo stretchy="false">)</mo><mn>2</mn></msup><mo>=</mo><mn>1257..</mn><mi>i</mi><msup><mi>n</mi><mn>2</mn></msup></math>) because it is concentrating the sunlight from a greater area. But the Fresnel lens has some disadvantages compared to the parabolic mirror that out weigh the small 19% larger area

The Fresnel lens has many concentric rings of glass (or plastic) with their surfaces tilted at slightly different angles to the normal. Perpendicular light from the source is refracted by this glass so the light is redirected toward the focus of the lens.
light is reflected as well as transmitted at each surface according to Snell's Law.
Some sunlight (and visible light in the case of simulators) is absorbed in the glass.

Even for a more expensive "optically perfect" lens, The transition of glass from one ring to the other is not perfectly sharp and area represents waste from an angle of glass that doesn't direct light to the focus.
Fresnel lens using thick glass will be very heavy to mount. Fresnel lens with floppy plastic requires additional mounting to keep it flat or the focus will be degraded. Thinner plastic may even stretch over time.
Assuming the image device is high resolution with a wide color frequency range, glass or plastic will transmit a narrower band of the light frequencies than a silvered metal mirror of the parabola will reflect.

No answer is simple as it often turns out. :grin:

My back-of-the-hand suggestion based on my bias (of course):
If low-cost with high quality and least amount of design / construction is the goal -
Look at my simulators. They are proven pre-built beamsplitters and concave mirrors.
Update the 20" monitors with a newer high-resolution tech with high refresh, higher resolution, and brightness - but true color. The cabinet on top can then be shortened (the overall height) by around 20" because that use to be the CRT yoke.
This takes care of the virtual center window - the older Multifunctional displays can be replaced with other instrumentation.
Put the entire set up on wheels. Take it to conventions, shows or other public facing shows.
It would be easy to charge for a 7 minute session and get between $8.00 to $15.00 for a high-resolution experience (that is 6 an hour). A three day event is only around $1,500. This is presently being done with the old, vga direct 7 versions. When my kid was younger and in CAP, I was happy to pay many times more for him to experience flight sims.
I would love to keep two units and work with a team of 5 others with two to develop something together.
But, that is another story. :mrgreen:

Article worth watching for 240 Hz refresh rate and motion blur. Also covers Plasma and DLP
https://www.cnet.com/news/what-is-refresh-rate/
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Here are some shots of my visual system. The construction was done in considerable haste, this is more a proof-of-concept/experiment than a polished sim (this sim is basically a test bed for new ideas).

The black triangular box was adapted from the AST-300, and now houses the projector:
http://www.mycockpit.org/forums/atta...id=12212&stc=1

A shot of the Fresnel inside the cockpit...the proximity of the lens as compared to the instrument panel is not ideal from an aesthetics standpoint, but in actual use it's only a minor annoyance:
http://www.mycockpit.org/forums/atta...id=12213&stc=1

Looking from the front of the sim, here's the projection screen in front of the pilot:
http://www.mycockpit.org/forums/atta...id=12214&stc=1


And finally, a shot of the "hidden room" showing the projector above the cockpit:
http://www.mycockpit.org/forums/atta...id=12215&stc=1

The geometry of the system should make it possible to do two of these screens side-by-side for a two-pilot cockpit. Having the two separate (but identical) views would be like some of the older commercial sims. Right now, I just have a 19" monitor mounted on the right side of the cockpit, for instructor use. It mirrors the pilot's view (it's fed directly from the projector's aux output), so it's useful in keeping the instructor abreast of the student's in-flight shenanigans. A less mobile but more versatile option would be to give the instructor a dedicated station outside the cockpit, with the duplicate view, as well as extra screens for maps, failure modes, sim operation, etc. This is the route I'll go with the Sabreliner, most likely.

The immersion factor with this visual system is simply no comparison to the old projector-only setup I had before. I actually WANT to FLY this sim, a lot! I can already tell that getting the outside world completely shut out (by putting on doors, and finishing the instrument panel) will help immersion even more.

The good thing about wanting to fly more than work is that I've had a chance to really put the sim through its paces, and discover/fix various usability and stability issues. The sim has essentially been on a "feature freeze" for several weeks now, and has really matured. Next step is to get my King HSI going (I'm getting a little tired of having to look at WingX Pro on my iPad just to figure out my heading).

Matt

Hi Matt, this is great!

Thanks for sharing, it is exactly what I've been looking for.

I've been to a few flight simulators (private builders, and commercial -- more for the general public) and have been disappointed with the visuals. Although they have a complete 180 degrees or more wrap around screen, it does not feel immersive.

I am looking to see if using fresnel lenses (as you have done) would be a feasible method and relatively straight forward way to implement a collimated display system.

Could this kind of setup be possible with an A320 visual display setup? It would be difficult to find or source a fresnel lens that large, but perhaps setting up 2 side by side display will still have a good effect?

Cheers,

Ben

Thanks for the post of the C-20 Glass Mountain kit for use with a 20" monitor.
Amazing enough, I was able to contact the individuals at Flight Safety that worked for Glass Mountain who set up the specifications for the Tesla II simulators. Was even able to get a phone call and ask many details about them.
A lot of old rumors dispelled by the pros.
The C-20 is designed for flat screen. The monitors shipped with them were pretty flat for CRT's. But, the mirrors were not set to accommodate the slight curve as some people has misinformed me. That makes them great for the new technology.
Found out a lot more interesting things. Will come back and share that this weekend.

Thanks for the photos up above!

Ben,

I know what you mean about underwhelming visuals. They can make or break the whole experience. It's particularly an issue for me, as I'm all about the flying primarily, what happens in the cockpit is not always my focus. I flew an Aeronca Champ today that had airspeed, altimeter, compass, and not much else. Most of my time was spent looking out the generously-sized windows. :)

A few years back, I did get to check out what could probably be considered the pinnacle of non-collimated wrap-around visuals, at Flight Safety. It was a level 6 FTD for a Eurocopter sim. The system itself was amazing (the actual graphics, not so much...they were using Google Earth...), having such a huge FOV filled by seamless sim graphics really gave a great flying experience, especially since it was a heli. But, I have to say, it did not have the same "wow" factor or level of immersion as a good collimated system. It's hard to explain, there's just something about those systems that just pulls you into the virtual world like nothing else. Not even virtual reality glasses are any match for it.

Anyways, Ben, if you try to use this system on a big cockpit like an Airbus, you're going to run into the same issues the big boys used to have, such as seams between the channels, and getting each channel to look right from both pilot positions. But we do have some display technology now (such as cheap bright DLP projectors) that those old systems did not have. If I were to try this on a bigger cockpit, I'd probably start by doing 3 to 5 flat projection screens, with a projector beaming onto each, and an equal number of big Fresnel lenses in front of them, but with nothing separating these screens/lenses from each other. What I find with my rig is that I can move my head around quite a bit and still get a good image. I also find that the edges of the image get "pulled" a bit, sort of like the fisheye effect you get with a spherical system. This is a GOOD thing, as it gets us away from the unrealistic flat image we typically see in projection systems.

Tesla3D, that's some exciting news about the Flight Safety stuff. Keep us updated, I'm looking forward to hearing about it!

I'm attaching a few shots of that helicopter system in case you guys are curious. Sorry these are of such low quality, the light was very low for the visual system to look right. One thing that struck me about this system was when it crashed/reset (not on my flight, hehehe) all the projectors went red....I noticed a LOT of projectors with a LOT of overlap. That was surprising.

Matt

http://www.mycockpit.org/forums/atta...id=12220&stc=1http://www.mycockpit.org/forums/atta...id=12221&stc=1http://www.mycockpit.org/forums/atta...id=12222&stc=1

You can build a DIY collimated display as per Gene's design, but it takes a little skill and a bit of space. Lots of pics and details on the forum under the "2 Place Collimated" thread.

Folks from as far away as California and North Carolina have been by to fly the system. If you are near Colorado Springs or just passing through always glad to share the experience with fellow simmers.

Cheers
JW

Hi JW,

A Gene Screen is indeed the way to go, from what I can tell of its construction. I've used the "big boy" sims with the same type of system, and it's the best there is, IMO. I think I might have mentioned to you a while back that I have the back projection screen from a Flight Safety level D sim (either Learjet or Challenger, not sure which sim it came from). I'd love to use my screen with Gene's design. Problem for me is space.....I only have a two car garage, and I have long outgrown it.

Maybe once my wife and I get our place in the country (within 4 years if all goes well) I'll be able to do a full visual system. I'm still keen on further developing what I have, however, as it will be more suitable to mobile sims, and achieves nearly the same effect (just on a smaller scale).

Matt

Cheers thanks Matt -- I will think about your feedback and how to implement these lenses -- getting them all the way to Australia is a problem it itself.

Would your setup be akin or similar to a WAC? ( http://doti-optics.com/product.php?product=collimator )

I can see how it may be limiting for large aircraft because of the limited FOV, but you will be looking straight ahead and I don't think that would be much of an issue.

Speaking of Gene and wledzian -- their visual screen is on sale, but I don't think the Classified section is functioning correctly and it hasn't been updated since February?

Good point, shipping and handling makes a difference.
Was just looking into the cost of putting 12 entire cockpits on a sea container for shipment to China.
Have clearance and opportunity get first had on-board tour of shipping container operations in Long Beach.
Of course this is for the C-20 Glass Mountain mirror and beam-splitter kit for use with a 20" monitor.
The sims are 3.5'x7.5'x7'H The height could be cut down considerably by replacing the old CRT with the newer high-resolution flat monitors. They are narrow enough to put side-by-side for dual pilots to each have a perspective view. One unit is small enough to put on wheels and take to convention shows.
I worked on a larger unit for helicopter back end gun training. Those were huge and had "some assembly required".

The WAC in that link looks an awful lot like the C-20, I'm guessing it's the same technology. If so, it uses a beamsplitter, so it's not exactly like my setup. Without comparing the two types in operation side-by-side, I'm somewhat at a loss as to what the beamsplitter does for you that a good Fresnel won't.

Yes, Wayne is trying to get rid of the prototype Gene Screen, the problem is size....unless someone in the community is able to stop by his current location in Washington state, I'm afraid that fine piece of engineering may end up scrapped. I'd get it myself, but I'm all the way in Oklahoma.

Matt

Quote:

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Originally Posted by xplanematt

The WAC in that link looks an awful lot like the C-20
Matt

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Sorry, its been a while, some great opportunities abound! :D

Didn't see a price for the WAC. Please do tell!
This weekend, just got permission from eBay to list things. For the price they had to conduct a 60 day full credit check.
Credit to them for keeping out fake business advertisement.