More Aesthetically Pleasing Table Design
Posted: 05 May 2008 09:16 PM   [ Ignore ]
Rank
Joined  2008-05-05
Total Posts:  4
New Member

I’ve been toying with the idea of designing / building a multi-touch table for a while; and recently an application idea came to mind that has re-kindled the dream of building an FTIR touch surface with an LCD behind it. I’m going to explain the physical build of the box, and included are some images of a 3D model so you can see the overview.. I’ll also post the design elements seperately to further illustrate how the pieces are supposed to fit… This isn’t a completely finished design, but the area I am concerned about is shown.

To give some background on why I have chosen this design before you take a proper look at it; I have a large glass coffee table in my lounge, it’s got a very elegant metal structure beneath it with lots of free space; I tried to model the frame holding it up, but couldn’t get the curves right; needless to say, I’d like to turn this table into a multi-touch coffee table. I thought about using the original glass, but I can’t see it working without me cutting a hole in the middle of the glass and I’d rather save the piece so if I ever wish to turn it back into a normal coffee table, I don’t have to hunt for another large piece of bevelled toughened glass (Plus, I would probably smash the piece trying to cut out a 22” diagonal rectangle from the middle...)

My main concern was that the touchable surface will be in the center of a much larger piece of acrylic, and I’d obviously like the two to be as flush as possible. As such I have designed a central box to house the 22” LCD matrix, two Microsoft NX-6000 Cameras I read about on here with a 71 degree viewing angle which will allow me to cover the full touch surface with a box just over 8 inches deep (This obviously can be adjusted if I find more suitable imaging hardware, I’m looking into a few different multi camera setups to provide a capture resolution close, if not greater than that of the currently chosen LCD panel). Lighting, again, I’m being experimental by adding boards to the box internals, as high as they can be without obscuring the cameras view; in the new trenches i will add the illumination sources and give them reflective sides, above the height of the partitions, I intend to coat with a light absorbant material; most likely a matte black paint (blackboard paint potentially), I am also looking into adding fresnels to the top of these channels to disperse the light out over the whole panel as evently as possible. I’d love some input on this concept, is it workable? has anything like this been tried before? if so, what were the results? (Obviously each lighting area will have it’s own ventilation. Back to the top again; The frame housing the IR LED’s is 1/8” lower than the height of the Acrylic touch surface. The larger piece of acrylic will be cut down and have a lip to allow the two pieces of acrylic to sit flush along side each other. I am wondering what sort of effect this will have on the FTIR concept; I’m sure there will be some IR leakage, but will it be significant enough to screw up touch recognition?

I would obviously like to bond the two pieces of acrylic together; possibly permanently; using some form of plastic cement or other process to give a completely flush coffee table surface, with a touchable inner screen. I am thinking about some form of IR reflector to place between the two pieces with the tiniest ammount of Acrylic left at the surface purely to bond together and polish smooth. Can anyone shed any light on whether this is even worth trying?

So here’s the top sheet, as you can see, the inner window has a lip of around half an inch which will sit over the frame for the touch window:
?ACT=28&fid=17&aid=862_1Sbz8micJ1YkjNpdtzMk

Here’s the framed acrylic; perhaps a few too many LED holes, but at this stage I just wanted some holes in there:
?ACT=28&fid=17&aid=860_CshwQI8oq7dRxU9OjxT1

Here’s a top down view of the main housing, the layer on top is shown as a piece of glass to represent the LCD matrix, further refinements need to be made to finalise this setup; also please note that the diagonals you can see inside from the two points were me working out the viewing areas for the two cameras, although it doesn’t appear so; the camera fields actually overlap by approximately 20 pixels, sketchup just isn’t accurate enough:
?ACT=28&fid=17&aid=863_tEJZhPPsrzRTSibYpeIo

And now the finished item; note it is missing the frame to support the whole structure, but I’ve got that item sat in front of me here, I might take a picture with my cam if anybody is interested smile :

?ACT=28&fid=17&aid=859_wS1CPpfr89otJUaSyEZA

You can also see the ventilation holes for the lighting channels; these will obviously be fanned and baffled in the final design to improve airflow and reduce light leakage respectively smile

Let me know what you think.

Mike

Image Attachments
Multi Touch Table.jpgTouch Surface.jpgUnderside Top Sheet.jpgMain Housing.jpg
Profile
 
 
Posted: 06 May 2008 03:36 AM   [ Ignore ]   [ # 1 ]
Avatar
RankRankRankRank
Joined  2008-02-12
Total Posts:  1111
Member

Hey Mike,
First of all welcome to the forum, good to have you here.
I was planing on building a very similar table to your design but decided to go against it. Mainly cause, it was out of my budget… good to see that someone else is giving it a go, found out Acrylic was way to expensive here in canada and glass was very heavy.
I’m now going with a design similar to Tim Roth’s DI table and Fairlane’s Table but mine going to be FTIR not DI.

In my view a design such as that is more suited for a DI setup since a single piece of acrylic or glass can be used as both the touch screen surface and table where the area under the box would be multi-touch and the rest part of the table.

hope your design works out and we are able to see it in the showcase section of the forum soon

Cheers
Taha

 Signature 

Company Website - Knode Research and Development
My Youtube

Profile
 
 
Posted: 06 May 2008 06:02 PM   [ Ignore ]   [ # 2 ]
Rank
Joined  2008-05-05
Total Posts:  4
New Member

Hmm, thanks for your response Taha, nice to see an active community here working on these projects smile Hopefully I should have a little backing from a couple of work projects this could be benefitial to, so although I’ve got to keep costs down thanks to this only being conceptual work at this point… It should still give me a bit more cash to throw at it.

I’d like to do a DI table, but I’m not sure how well that will work with an LCD instead of a projector… perhaps I’m just being ignorant; but the FTIR option just seems a little simpler for my needs (barring the potential edging issue) I don’t need to ask again really, but can anyone see any problems with potential IR leakage out of the central acrylic? or should the reflective barrier I intend to put there do a good enough job even with maybe 1 or 2mm at the top bonded to the other piece of acrylic?

Once I’ve done enough fact finding on this, I’m going to start up about it on my blog and document the whole process smile

Profile
 
 
Posted: 07 May 2008 07:39 AM   [ Ignore ]   [ # 3 ]
Avatar
RankRankRank
Joined  2007-09-22
Total Posts:  263
Sr. Member

Until now 2 members here have had succes with lcd based mt tables.Both have included project logs , search the forums here and welcome to the community (I would have given you direct links but i’m in a hury)

Profile
 
 
Posted: 07 May 2008 08:01 AM   [ Ignore ]   [ # 4 ]
Rank
Joined  2008-05-05
Total Posts:  4
New Member

Hi Vlado, I’ve read some project logs for MT tables with LCD screens, but I’ve not read an MT using DI and an LCD, hence why I’m going for FTIR… I’ll have another hunt for DI with an LCD, as I think that better results could be achieved; especially as I wouldn’t have to use two pieces of acrylic just as Taha suggested… I’ll keep reading and researching, but I’m going to do a build with an old 15” LCD I’ve got knocking around just to test my two piece FTIR concept; if it works it’s time to get a larger panel and start the real build smile

Profile
 
 
Posted: 07 May 2008 11:41 AM   [ Ignore ]   [ # 5 ]
Avatar
RankRankRankRank
Joined  2008-02-12
Total Posts:  1111
Member

Hey Zwitta, i think you should contact nima, i believe has done a front illumination DI setup on an LCD screen as well as FTIR using LCD.

Taha

 Signature 

Company Website - Knode Research and Development
My Youtube

Profile
 
 
Posted: 12 May 2008 06:34 PM   [ Ignore ]   [ # 6 ]
Rank
Joined  2008-05-05
Total Posts:  4
New Member

Thanks Taha, work has gotten a little crazy for the next 2 weeks while we move one of the companies into a new premesis, but after that I’ll have some time on my hands again; ready to work on the fun stuff smile I’ve been doing some talking with the guys on the mediaPortal forums, I’m going to put together an application for controlling my media center PC via the coffee table; so I’ll have my media library scrollable and searchable on the coffee table, then be able to “throw” the files towards my big screen to watch them smile Handy things like the progress bar and volume controls will also be appearing on there too, so it should be something that will get used very regularly round at my place :D

Profile
 
 
Posted: 18 October 2010 08:26 AM   [ Ignore ]   [ # 7 ]
Rank
Joined  2008-06-29
Total Posts:  76
New Member

Hey Zwitta, it seems that you are not working on this Forum any more. But has anyone else the plan to use Mediaportal on his Multitouch?
I didn’t find a Plugin yet that makes me control the Menu by Scrolling with the HID Driver, it only detects a Click. So its unusual to control it.

Profile
 
 
Posted: 18 October 2010 09:36 AM   [ Ignore ]   [ # 8 ]
Avatar
RankRank
Joined  2010-05-31
Total Posts:  181
Member

I also tried Media Portal without success.
There are some Desings that support Touchscreens. But no Multitouch :(

greez

JonnyB

 Signature 

There are only 10 types of people in the world:
Those who understand binary, and those who don’t.

Profile