-
2 Attachment(s)
2 Place Collimated Display
I started working on the new collimated display design yesterday after our resident Mathgician worked his magic. (*waves at Wayne*) :D
This first new project will fit cockpits that are Cessna 182 sized. It should also work out for small bizjets like _maybe_ the Lear 45 or some of the smaller Embraers.
That being said, this thing is NOT small. The 180 degree screen design is 86.444 inches wide (that's about 7ft 1/4in). The mirror will have a radius of 72 inches and will take up more space than that as the sphere radius is defined inside the framework. Once I get the rest of the components completed, I'll be able to tell you how much ceiling height you'll need. :)
Here's two renders of what the screen components look like. There are three primary components to the screen - an upper frame, a lower frame and and upper frame spreader bar. The shape is defined by 30 "blades" that will fit into the upper and lower frames. This build will go just like the last one did with respect to the screen.
Attachment 6588
Attachment 6589
I don't know yet how much this will cost. I do know that we'll offer both CAD drawings on CD as well as a "short" kit that will consist ONLY of parts that really should be CNC cut. You'll be on your own for the rest of the materials, fasteners and Mylar - we'll point you to our vendor so you can buy the film directly from them. The part kits will be shipped in crates made from 2x4s and 1/4" OSB. The material used will be 18mm and 12mm (essentially 3/4" and 1/2") Russian Birch.
If you don't want to worry about shipping & crating charges, the CD will include all the necessary files to hand off to a local fabber - they can be found at http://www.100kgarages.com.
Wayne tells me the 737 mirror will be a bit over 15ft in diameter, so if you guys with the big jet habit REALLY want a collimated display, you'd better hope you've got room for it. :) I would recommend consulting a good engineer before you start cutting rafters though. *laughs*
I'll update this thread as progress happens.
g.
-
Re: 2 Place Collimated Display
Sweet! Anything worth doing is worth doing to excess!;)
Looking forward to it, Gene.
-
Re: 2 Place Collimated Display
Quote:
Originally Posted by
geneb
Wayne tells me the 737 mirror will be a bit over 15ft in diameter, so if you guys with the big jet habit REALLY want a collimated display, you'd better hope you've got room for it. :) I would recommend consulting a good engineer before you start cutting rafters though. *laughs*
g.
So what you're telling me, Gene, is that as soon as I get to Germany next month, I should be shopping for a house with a room at least 15' wide? Check!
-
Re: 2 Place Collimated Display
Sign me up for the CD Gene...
-
Re: 2 Place Collimated Display
Ditto!!!! CD for sure. And, depending on the price point the pre-fab may be of interest.
I believe I've got the space for the radius mentioned, but the height may be an issue so I'll be watching closely to see what that turns out to be. I guess I could always try to snag some warehouse space from the family business...
-
Re: 2 Place Collimated Display
Thanks all!
The 15' diameter is for the mirror sphere _only_. The framework will add 24" or so (at least) to each side.
One of the design changes I'm making for the new mirror chassis will be a better looking back to the assembly. The back will be made of a pair of 1/8" hardboard panels that are laminated into a conic shape on a jig.
This design change will do a few things:
1. It will remove the need for a special grid support structure to prevent the back from deforming under vacuum.
2. It will greatly reduce the interior air volume of the mirror. The airspace on commercial displays is very small - typically there is very little space between the back surface of the mirror and the front surface of the vacuum plenum.
3. It will reduce the width of the mirror chassis, but not by much. :)
The conic back sections will be probably the trickiest parts of the whole project to build. The two parts that make up the lamination will be different sizes to account for the k-factor when you bend them in order to make the edges line up correctly. Forming the sections will require a two part jig. The bottom will be a "positive" shape and the top will be a "negative" shape. The 2 1/8" hardboard sheets will be clamped between these jigs in order to form the sheets into a conic section that will retain it's shape when the glue dries. You'll be able to make the jig out of 7/16" OSB which is a pretty cheap material. You're only going to use it three times, so it doesn't make sense to use expensive plywood for it.
g.
-
Re: 2 Place Collimated Display
Hi Gene,
Is that 24 inches x 2 = 4 feet added to the 15 foot diameter". Seems like that would create a rather large volume? Also what is the diameter of the mirror at the bottom? 15' x cos( 50 degrees ) = 9.64' ? Ceiling height is 12' don't think that will be a problem and length of the space is 24'; however depth (width) of the stall is about 12.5 feet. That might be a little tight, but doable.
Regards
Jack
-
Re: 2 Place Collimated Display
Jack, remember that the diameter of the mirror is as measured at the film itself. That doesn't include any structure to support it. My 24" addition to each side was simply a guess based on what I've got now. Also, the mirror is only 40 degrees high (0 at the top, down to 40), not 50.
--edit--
After thinking about it a little bit more, the "extension" past the mirror diameter will more than likely be under 8". I simply got my top & bottom dimensions flipped around.
-------
I've been catching up on house maintenance tasks this week, so no new work has been done. (I'm about six months behind THAT too. *sigh*)
g.
-
Re: 2 Place Collimated Display
Having just moved I know the feeling, the "honey-do" list keeps growing while a lot of the sim parts are still in boxes :-(
Trying to visualize ( mirror/cockpit positioning ) the layout and tend to think in terms of two numbers; the screen diameter at the equator and at the southern edge of the FOV. Structure behind the mirror at the equator sets the total system size and the bottom number plus structure forward determines how much cockpit structure clearance exists when unit is positioned for the correct eyepoint(s).
Is the 15' mirror size based on the footprint of many of the shell plans available for the 737?
Might it be possible to use a smaller mirror? Reduce amount of materials required as well as the space. Or are we at the minimum acceptable limit?
Jack
-
Re: 2 Place Collimated Display
As far as I know, the 15' (approximate!) diameter is based on a real 737 flight deck section.
The size of the mirror is dictated primarily by the size of the simulator cab.
g.
-
Re: 2 Place Collimated Display
Most of the 737 sim shells truncate the nose section at the apex of the windscreen plus about a foot for one additonal rib for structual stiffness. From pilot's eyepoint to the front is around 6 to 7 feet.
The width at the forward windscreen (corner to corner) is 5.5 feet at the base and 7.5 feet at the rear of the side windows. allowing for a little bit of fuselage bulge below the windows might add about a foot. So the shell exterior is around 9 feet, maybe a little more or less. So the lower boundary is 15Xcos(40) = 11.5 feet. and you need some room, so maybe a 15' diameter mirror is right-sized.
Looking forward to the final set of plans you provide.
Jack
-
Re: 2 Place Collimated Display
Gene, I didn't see any mention of the release date of the CD.
It would be nice to get this job scheduled in before more gardening chores get me too exhausted to play ;)
Definitely put me down for one if those CD's as well.
Glad to see you're back in action !
-
Re: 2 Place Collimated Display
I didn't mention a date because there isn't one. :)
It will get done when it gets done - I'm not going to do a rush job just to get it out the door.
Last week I junked the screen design because I had a few errors in it and I didn't like the overall structure. It's been redesigned at 210 degrees and is a bit more stout.
g.
-
Re: 2 Place Collimated Display
[QUOTE=geneb;131038]I started working on the new collimated display design yesterday after our resident Mathgician worked his magic. (*waves at Wayne*) :D
Hi Gene,
when you have a sec how about a short progress report on the larger mirror system. And the smaller unit for that matter.
Thanks
Jack
-
Re: 2 Place Collimated Display
Sure!
The larger unit doesn't exist yet. :) The current design is for the Cessna 182 "sized" display.
As of Friday, the mirror cell design is completed with the exception of the "ears". (I'll get into that in a moment) I've also started on the support structure for the screen. I suspect I'll have this mostly completed by Wednesday night barring any interruptions.
The plan is to get this model completed and then begin design work on the 737ish sized model, followed by the "tiny" model that is the same size of the unit that Wayne & I built. The 737ish and tiny model designs should go a LOT faster as I will have solved all the integration issues with this first design.
After the tiny design is done, I'm going to build that and use it to write the assembly guide for the other two display designs. One manual will cover all three because while the size & geometry will be different for each of the three, the displays will all use the same shape & number of components.
After the new tiny model is built, I'll start looking for a guinea pig to build the Cessna 182 sized display. Jack, you're already my test victim for the 737ish unit. :)
When the test builders are done and happy with the results, I'll begin selling drawings and router templates.
I will warn you right now - if you don't own or have ready access to a good router, a full sized band saw and (likely) a table saw, you will NOT be able to build this display. If (and only if) demand is great enough, I may offer a "short" kit that would contain all the mirror cell ribs, screen shape ribs and other parts. I will be including the items necessary for a builder to have the parts CNC cut with as little hassle as possible. (Pre-nested parts layout on a 4x8 sheet, etc. I'll also include Vectric VCarve Pro and Aspire design files so you can just hand those off to a fabber and they can run them will little hassle.)
Also note that for the Cessna 182 and 737ish designs, the foam used for the screens will likely exceed the material costs for the rest of the display. The screens are *HUGE* and will eat up a ton of foam to create the shape. This is one of the reasons I'm using test-builders - I simply can't afford the material cost to build something I'll never use. (They're just too big and I'm getting space-constrained in the shop as it is).
Now, as to the "ears"...
Here's the deal - I'm not going to provide design drawings for the end extensions for the display. After thinking about it a great deal and watching Apple go batsh*t crazy and sue Samsung over a rectangle with rounded corners, I'm not up for exposing myself to a suit if Rockwell-Collins decides I need to be made an example of.
That being said, what I will do is provide the builder with enough clues so they can figure it out. I'll post a ton of pictures of how I did it as well as point out the patent so folks can understand the science behind it. Hopefully the "beta" builders would be willing to share their experiences with it as well.
g.
-
Re: 2 Place Collimated Display
Hi G,
I'm sure looking forward to completion and finally being on your customer list :cool:
JT
-
Re: 2 Place Collimated Display
Any updates on the CD? Put me down for one.
-
Re: 2 Place Collimated Display
Would this work for a FDS Jetmax style cockpit?
-
Re: 2 Place Collimated Display
Starting down the road to insanity!
First a world of thanks and shout-outs to Gene and Wayne for their time and dedication in completing the design and review of the 737 mirror system. Their efforts and talents represent everything that is right with the world and serve as an inspiration to all hobbyists and DIY simmers.
The drawings and cut files have been sent to the CNC woodshop that will produce the various pieces for assembling the mirror system and will be delivered in two weeks. Then the fun begins in putting it all together....
A couple of preliminary thoughts and observations...
You ABSOLUTELY need a CNC router. The structure uses over thirty 4x8 foot sheets of plywood and hardboard of varying thickness from 3/4" to 1/8". Initially, I considered using a hand router but the amount of cutting and precision required quickly squelched that approach. Either you have a CNC router or access to one.
As to space and size, it is a large structure. The room where I'll house the sim is 16x22x11 feet. You might be able to get by with less floor space but you need the height (perhaps a min of 10 feet ) to hold the projection screen and if your sim sits on a platform above the ground floor you need to account for that as well.
Some of the parts you will have to build yourself, so some woodworking tools and a modicum of skills are required.
And, again, remember how the optics work. The mirror creates a virtual image focused at infinity, not an image projected onto a cylindrical or spherical surface. With a simple projection sysem you can "get away" with some imperfections, inaccuracies, and misalignment of the surface; with the collimated display that is not the case. Misalign, twist, malform the mirror and it will not work. accuracy and precision is the watchword!
Hopefully, will find the time to post updates, pics, and videos of the progress. as well as notes and tips on construction and assembly.
Cheers
JW
-
Re: 2 Place Collimated Display
Outstanding news, John. Looking forward to watching this come together. Keep us posted!
Warren
-
Re: 2 Place Collimated Display
Will do and when you return from your tour in Germany we'll have to think about building another one for your setup.
JW
Quote:
Originally Posted by
fsaviator
Outstanding news, John. Looking forward to watching this come together. Keep us posted!
Warren
-
Re: 2 Place Collimated Display
That would be great! Looking forward to already.
Warren
-
4 Attachment(s)
Re: 2 Place Collimated Display
It took about two weeks to produce all the pieces for Gene's design. In all it took all of thirty 4x8 sheets of varying thickness from 3/4" plywood to 1/8" hardboard. Started pulling it all together this Friday.
To produce the twelve collar sections for the mirror frame required laminating thirty six pieces into 30 degree arc sections
( three pieces per section ). Required a special bandsaw setup to cut the 20 degree bevel required to hold the collar mask and clamp. The pieces are just too large and heavy to try and work without a jig to hold the cut on line. One comment to Gene, we might want to rethink how these parts are produced for the larger design.
Attachment 7590Attachment 7589
Not totally convinced this will work especially for the much larger upper sections. But have some ideas if this proves too difficult without a more industrial sort of setup. Waiting for some new bandsaw blades before proceeding. In the mean time moving on to start on the wing ends. Once you see the pics it will be fairly obvious how to produce this section. Think about building a dish of a certain radius and then cutting it in half.
We said this was a large beastie, but studying the CAD files alone does not fully impress upon the reader the size until you see it up close and personal. Here are a few more pics of the wings. (Hint) Can you draw a circle?
Attachment 7591
Attachment 7592
Cheers
JW
-
Re: 2 Place Collimated Display
Wow, please keep us updated!
-
Re: 2 Place Collimated Display
What would be the space requirements for a GA collimated display for a 182 size cockpit?
-
5 Attachment(s)
Re: 2 Place Collimated Display
Time for a short progress report. The two end sections for the mirror frame are completed.Attachment 7643Attachment 7644Attachment 7645
Will add a two more cross-stringers to beef up the back and prevent "oil-canning". going to hold off adding the front semi-circular cover until mating with the adjoining 60 degree section.
here is a pic of the projection screen frame and ribs.
Attachment 7646Attachment 7647
To save weight the collar was cut from 1/2" ply. Then the puzzle joints were doubled with 3/4" ply to increase strength and rigidity. Won't get around to actually building the projection screen until the sim room is ready around mid-May, weather permitting we should start construction in a couple of weeks.
Cutting the frame collars for the 20 degree bevel was very successful. You can go to youtube, search on "737castle" and view the short video. Will be posting additional videos on project progress as time goes by. The not so good news is that using the lower grade of plywood resulted in some warping on the sections that could not be corrected. Decision was made to recut the mirror pieces with a better grade of birch plywood that was very close to cabinet grade. These were delivered today and will start fabrication of the 60 degree sections later this week.
Hmm, seems more like a wood working project ;-)
Cheers
JW
-
3 Attachment(s)
Re: 2 Place Collimated Display
recutting the mirror frame pieces was a lesson learned -- better to spend a little time and expense to do it right the first time. The mirror is critical and any warping or misalignment will ruin the collimation.
Attachment 7648 Attachment 7649 Attachment 7650
the lower curved pieces in the second pic are the guides for constructing the table on the bandsaw to help align the collar sections as they pass through the saw for the 20 degree bevel cut.
Next I'll post some pics of the support table. Here it is also important to make certain the structure is level to avoid bending of the mirror frame and strong enough to support the weight.
Cheers
-
Re: 2 Place Collimated Display
-
Re: 2 Place Collimated Display
Hi all, i have already my Sim working whit fresnel, it looks good but collimated dsplays are almost a dream , i am trying to get some Information about the optics, now looking this excelent work the collimated displays looks not impossible, how i can contact to geneb for Information And cost ? Thanks for sharing this work
javcr@cever.com.mx
-
4 Attachment(s)
Re: 2 Place Collimated Display
This will be my last progress report for a few months. starting construction on the new workshop(man-cave) next week. Once that is done, hopefully in late August will reassemble the sim and display system in a more permanent configuration and setup.
Preassembled the mirror frame; the platform to hold the frame must be square and level. can't emphasize that point enough. On the initial go around the back legs were a tad short resulting in a very slight tilt to the rear. This combined with the weight of the upper collar produced about a 4-5 inch gap at the ribs joining the ear extensions due to a moment or torque which tried to pull the sections apart. That problem will be corrected with adjustable table levelers inserted in the platform legs when final assembly begins.
Here a few pics before I start taking it apart. It is huge! The new workshop will be 22x17x11.5 feet. With the size and linear length of all the edges and joints forming the chamber, taking extra care and time to form good seals to minimize leakage when drawing down the mylar. As well as corners and joints to form edges to hold caulking and sealants.
Just flat ran out of room in the present space to build and pre-assemble the projection screen, so that will have to wait until later.
Have a great summer and see you all in September
Cheers
-
Re: 2 Place Collimated Display
Looking good, John. I'll be waiting! Have a great summer. Has it stopped snowing there yet?
-
Re: 2 Place Collimated Display
Hi Gene,
I know this was originally the thread for the 2 place general aviation size screen. It sounded like you had completed the design phase and I was wondering if it was at a point you could sell the CAD drawings? I realize the manual may not be completed but thought you might sell the drawings and write the manual as some are built. If so, let me know as I am ready to purchase either drawings or a short kit (although I have a good size CNC router with Aspire/VCarve).
BTW, I built a Rostock Max and lo and behold, who wrote the excellent manual for it...you did! Excellent job!
I apologize if this is the wrong thread to inquire.
Best Regards,
Tim McNamara MD
-
Re: 2 Place Collimated Display
Tim, due to outstanding patents, I'm not going to be able to publish plans and such like I wanted to.
I'd promised the project to Castle before I fully understood where I stood with regard to the outstanding patent that my design uses. To avoid being turned into a greasy stain on the floor of some courtroom, I decided it would be in my best interests to not provide CAD drawings or plans to anyone else, sorry!
Congrats on your Rostock MAX! I hope you enjoy the machine. It's a blast. :)
g.
-
Re: 2 Place Collimated Display
Hi Gene, I understand completely. Would you be willing to pass on the name of the supplier for the larger mylar?
Thanks,
Tim
-
Re: 2 Place Collimated Display
Oh certainly! Unfortunately, it's on a sticky note at the office and I'm on vacation this week. Castle, can you post the source I pointed you to for the Mylar for Tim?
I'll send a note to my work address on the off chance he doesn't get to it by Monday.
g.
-
Re: 2 Place Collimated Display
Quote:
Originally Posted by
geneb
Oh certainly! Unfortunately, it's on a sticky note at the office and I'm on vacation this week. Castle, can you post the source I pointed you to for the Mylar for Tim?
I'll send a note to my work address on the off chance he doesn't get to it by Monday.
g.
Also have been on vacation, but see you have posted the supplier. One comment, depending on the width of mylar you desire they can provide the specified size with one caveat. There is a limit on the size UPS will handle. Above that number you have to ship via freight and that is a tad more expensive. So if you want something for the 737 size, for example, might as well order a bunch (I got a thousand foot roll of 124" width). Never know when you might damage the mylar by dropping a tool, smudging the finish, or whatever. ;-)
-
Re: 2 Place Collimated Display
Quote:
Originally Posted by
castle
Also have been on vacation, but see you have posted the supplier. One comment, depending on the width of mylar you desire they can provide the specified size with one caveat. There is a limit on the size UPS will handle. Above that number you have to ship via freight and that is a tad more expensive. So if you want something for the 737 size, for example, might as well order a bunch (I got a thousand foot roll of 124" width). Never know when you might damage the mylar by dropping a tool, smudging the finish, or whatever. ;-)
Ooops, got my numbers mixed up. Bought a 1000 feet of the two side sticky tape and 400 feet of the mylar. That should be enough for 10 "tries" or re-skins of the mirror. Estimating the mirror will require a single section of mylar between 35 and 40 feet in length and about 100 feet of tape. The freight charges are pretty steep, so might as well by a bunch. ;-)
The sim room is progressing nicely. Electrical, heating and drywall should be done this week. Hopefully will have it done is a few weeks and get back to the main event..
Cheers
JW
-
2 Attachment(s)
Re: 2 Place Collimated Display
Howdy,
Well after a number of delays due to weather and contractor availability ( the fires and floods the past two years has created a building boom in the area ) the "sim-cave" project is ready for occupancy. started moving in the pieces and such last week in September and began building the mirror frame.
With clear sailing, hope to have the frame done and positioned by the end of November. It is one HEAVY beast! So once it is set in place and sections connected moving it would be just about impossible unless one was to disassemble the sections. Then the plan is to build the projection screen -- another large item, and finally to set the screen and then skin the mylar. The size and weight suggest it's best to have everything in place and set to preclude an accident if the mirror was done prior and while hoisting the screen into place something slipped. With just an open cavity we have more flex and don't have to be as careful when moving around the structure.
-
4 Attachment(s)
Re: 2 Place Collimated Display
Howdy,
Time for a progress report and some pics....
Attachment 8330
Had to back up quite a ways to try and capture the entire frame and with my back against the wall still not enough. so here are shots of the left and right ears..
Attachment 8331 and the right Attachment 8332
My live model was not available to give an idea of size, so the 8' ladder will have to do. ;-) The white ring is the two sided tape. The silver tube on the right edge is the roll of mylar. The team to attach the mylar has been assembled and we're discussing the best way to proceed. For you math/geometry types. consider wrapping a sheet of paper around a cone. In theory, you could calculate the size and shape of the mylar, add a margin , find an open basketball court, and cut away. In practice, think we'll go at it starting from the center and work toward each ear one side at a time.
Attachment 8337 Attachment 8338
I made some major mods to the spider design to lighten the weight and allow for assembly "in-place". Reduced the width of the arms and added doublers to retain strength and added a member to the hub to join the rear arms. The lower portion of the projection screen arc was hoisted into position after the hub and the arms were set in place. The ribs for the screen will be attached after the mylar is in place.
Also going to reduce the weight of the screen by cutting holes in the ribs. This will reduce the weight from around 50 lbs to around 35lbs; not a lot, but every ounce helps.
Attachment 8343
And finally a shot of the carriage frame to hold the 737 cabin. Installed on casters so as to enable one to slide the unit away from the mirror and provide more space for access to the electronics housed behind the MIP and above the overhead, as well as the flight controls and control loading mechanisms.
Attachment 8336
Still a few nits to work on as well completing the exhaust setup. We'll probably attack attaching the mylar after the Thanksgiving holidays.
Will be glad when this is done and I can get back to writing/updating software for FlightGear, the 737 glass displays, warping code, and reassembling the cabin to make it all come ALIVE.
Cheers
JW
-
5 Attachment(s)
Re: 2 Place Collimated Display
Nuts!!
left earAttachment 8347 right earAttachment 8348 centerAttachment 8344
Somehow I messed up some of the thumbnails and attachments, so here is a core dump of the missing pics
spider from above Attachment 8346 from below Attachment 8345
My apologies for the screwup
JW
Quote:
Originally Posted by
castle
Howdy,
Time for a progress report and some pics....
Attachment 8330
Had to back up quite a ways to try and capture the entire frame and with my back against the wall still not enough. so here are shots of the left and right ears..
Attachment 8331 and the right
Attachment 8332
My live model was not available to give an idea of size, so the 8' ladder will have to do. ;-) The white ring is the two sided tape. The silver tube on the right edge is the roll of mylar. The team to attach the mylar has been assembled and we're discussing the best way to proceed. For you math/geometry types. consider wrapping a sheet of paper around a cone. In theory, you could calculate the size and shape of the mylar, add a margin , find an open basketball court, and cut away. In practice, think we'll go at it starting from the center and work toward each ear one side at a time.
Attachment 8337 Attachment 8338
I made some major mods to the spider design to lighten the weight and allow for assembly "in-place". Reduced the width of the arms and added doublers to retain strength and added a member to the hub to join the rear arms. The lower portion of the projection screen arc was hoisted into position after the hub and the arms were set in place. The ribs for the screen will be attached after the mylar is in place.
Also going to reduce the weight of the screen by cutting holes in the ribs. This will reduce the weight from around 50 lbs to around 35lbs; not a lot, but every ounce helps.
Attachment 8343
And finally a shot of the carriage frame to hold the 737 cabin. Installed on casters so as to enable one to slide the unit away from the mirror and provide more space for access to the electronics housed behind the MIP and above the overhead, as well as the flight controls and control loading mechanisms.
Attachment 8336
Still a few nits to work on as well completing the exhaust setup. We'll probably attack attaching the mylar after the Thanksgiving holidays.
Will be glad when this is done and I can get back to writing/updating software for FlightGear, the 737 glass displays, warping code, and reassembling the cabin to make it all come ALIVE.
Cheers
JW