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Multi Touch Pad. Would this design work? Answered

Found this video on how to make a multi-touch table for your PC.

But that model have 2 big problems. It's ugly and it's too high.
But I really want to build one. 'Cause that is what I've always done,
built my own small electronical stuff. Anyway. I've been thinking and
I've designed my own model based on a webcam with a microphone.

The picture says it all acctually. Do you guys think it would work, or is the cameras angle of view to small to have the height I want? Does my Size and shape seems resonable or do I need to rethink. And about the LED's. It would be cool with red light coming up from inside it. And it would match quite good with the oak frame (have lots of Oak-pieces I can't use for something so I will make a nice frame out of it), and in the dark it would be very cool with light coming up from inside it, but that would disturb the camera by removing the dark spots created by your fingers, or am I wrong? Maybe I could put them discretely in the four corners above the table itself.

What do you think. Possible or not?
It works with a little height, but I will strip down the camera so that I can put the lens really low and not put in the whole camera.

To read the text on the picture you have to view them in full size.


If you look at some of the other multi touch designs on the site you should be able to see how to get it to work, the only difference being that to compact it, you could add a fisheye lens to the camera in front of the normal one to widen the field of view. You could also make a hole in the desk and sink it in to be flush with it if you're satisfied with the results...

Where in the hell did you model that?? That's totally awesome how you were able to do that.

Btw, that doesn't look like an oak grain (matter of changing the texture?) Lol

I'm looking and I see nothing pertaining to what he designed the images with.

I meant did you mean to reply to him, to ask the question, rather than my comment...

I banned myself from the computer while under the influence, then thought it would be fine, so I made my password trickier...

matter of making textures with higher resolution. I havn't had the energy to download HD textures.

Anyway. Here's the site for SketchUp. The free version is more than enough.
I've tried the Pro-version also but it's the same thing. Some 3D/2D tools more but nothing I ever used.

Google SketchUp 7.0. The Pictures that shows the complete model on the desktop is rendered using some random renderer plugin for Google SketchUp. But Google SketchUp is the program. It's free and Easy to use. Very good to make those plans in. And yeah, Oak, thats what I will build it in, But the Google SketchUp textures are so big, and I modelled it in the real size, so the textures are messed up on small objects.

I will add a Fisheye Lens and make the table quite small. I plan to use it for strategy gaming, and I've found a size that is big enough to press the right buttons but is small enough to keep down the height. And with LED's pointing down on the table I think the shadows will be very precise 'cause then it will be removing all the shadows created by things that are above the table. Anyway. I will start constructing tomorrow probably. Have been busy 'til now. Then It's just to wait for my camera to arrive from China.

And I apologise if I have made some language-mistakes. I'm not from the "English world" since I live in Sweden. And if you guys think this will work I will start constructing next week and put up a guide here on the site. Ordered a 300K pxl-webcam today and when it arrives I will put the electronics in the frame wich I shall have ready by then. And if necessary I can make the legs longer, but no more than 5 cm more. I do not want to have it too high, It should be desktop friendly. _______________________ Ok, Now I took a regular webcamera and meausured heights. At a Lensheight of 18 cm you can get a table the size of halv an A4. That might be enoug. So about 21x15 cm large table is possible with a height of 18 cm. The table size will be adjusted so that it has the same shape as a regular Laptop PC screen (3:2).

I would use something more 2-3mp camera, as it will probably have better framerate (more than likely) than a cheapy 300k pixel cam like mine which only gets around 15fps AT best. It also helps with fps to turn the auto exposure off.

All that is twakable. And I have never seen any WebCam with over 1.3mp. The Resolution is not the important, the framerate is. And even tho' the camera's quite cheap (at least on Ebay auctions) I don't think the framerate will be a problem. And even with a fps on 15 it will still register any shadows quickly. I considered most of the plan and I think it will work, otherwise I will work 'till it's working.

That is a really good idea. I've been trying the design on the computer, and it works, but the height required will make it stupid. It needs to be portable, but a fisheye lens is a really good idea. I shall try that, definitly. And then the "camerahouse" should be shaped like a cone. But with a Fisheye-lens I might be able to keep my 10 cm-height. Or I'll just make the pad even smaller, but then I cant use it precise so that is not a good idea. EDIT: Checked the features of the Web Cam I bought. Apparently it has a 180 degree view lens. So by just separating the lens from its housing and make the camerahouse a cone all should work out fine, without need for any annoyingly high table. Perfect! Tomorrow I will start with the frame EDIT 2 So, Now I've finished off the 3D model with the correct design and size. With a Fisheye-lens whole the table will be visible for the camera. And it won't be too high. Here you can see how it would look when it's finished and plugged in into your PC. As long as I don't rush I think I will be able to build it. And I've measured a few PC screens so that my touchpad will have the same shape. Most of the PC screens are 2/3 of the length in height. So for the table I used a 900x600 pxl-template, just to get the shape.