Open Source Interface

New job on the Horizon

2008-07-23T21:55:44-05:00

It looks like I’ll be working part time soon at the University of Hawaii Institute for Astronomy here on Maui as an electronics technician and machinist!
They spend most of their time looking at the sun on the summit of Haleakala Crater. Lots to do with UV and IR and bandpass filters… sound familiar?

I’ve been volunteering part time, just hanging out and sharing what I know like I do here, and I’ve learned so much already!
The lab has six optical benches and the facility has it’s own machine shop with a Brigeport mill. There’s also tons Thorlabs hardware in the place!

I’ll be starting out part time until they get the budget worked out so I’ll keep my day job.

Here’s some lab pics:
1. - A German student adjusting a camera with the sun shining on it from a mirror out in the parking lot.
2. - A large CCD cam.
3. - A small Hitachi camera.
4. - Thorlabs hardware and a deep red 5 mW laser used for aligning optics.
5. - Yes, that is indeed an xbox cam in a lab setup.

Cocoa OSC and TUIO questions

2008-07-21T04:09:50-05:00

Hello all,

I am in the midst of developing up a cocoa implementation of multitouch stuff. I was originally going to just build the framework and then build some apps on top of that (bypassing the TUIO stuff) but there has been enough interesting in a TUIO solution that I have redirected my efforts.

Anyway, 2 things:

1) i have implemented a mostly Cocoa-only OSC sender/listener ‘framework’ (it isnt a framework yet, just a bunch of source files).
It does all the bit-level ordering and decoding of OSC datagrams. It is a connectionless UDP implementation (which seems to be the going thing for OSC). The only big note at the moment is that if you are going to use it to dispatch messages for your own code (and i hope you do) you will need to develop your own dispatch code. BBOSC will receive the packets and decode them into bundle and message objects, so that is all done, but you would need to add your own code to make the “/osc/command arg1 arg2 arg3” do anything besides log to the console. I plan to add a nice callback registry for all that stuff, but i wanted to get the TUIO working in BBTouch first.

anyhow, what is there seems to be working dandy. you can get the code here:

http://code.google.com/p/bbosc/

and some notes here

http://benbritten.com/blog/2008/07/21/osc-now-with-more-cocoa/

2) the second thing is my question: I am new to the TUIO/OSC bandwagon. Implementing the protocol wont be too bad, but I will need to test it against something that is TUIO capable. So what out there is TUIO capable that runs on the mac? (that is preferably free and or open source) I can write my own, but that doesnt really test whether my stuff is compatible with other people’s stuff

I vaguely remember reading about some flash apps that should work (i do actually have flash 3, so i wouldn’t have to buy that) but i couldn’t seem to find them in my various searches on the forums. any help would be greatly appreciated!

cheers!
-panda

Simple Flash Client?

2008-07-23T11:46:21-05:00

Hello,

I’m working on a surface table that is going well. But i’ve got a problem with the software, i downloaded some source files but I can’t find the option I need. I see coloured dots while touching de surface. But how do I link a movieclip from my library to the dots. So where the dot is I want to have my movieclip.

The examples I downloaded where not based on movieclips so I can’t find the sulotion.

I hope someone can help with the Action script code for this.

Thanks a lot.

Ivo

Tables. TVs. Walls. What’s next?

2008-07-23T13:55:06-05:00

We’ve seen the tables. We’ve seen the upright TVs. We’ve seen the wall transformations.

We’ve seen a lot of very impressive work, and as a DIY community, we’re elevating this method of man-machine interfacing to a whole new level. So what’s the next step?

After talking a little with some others in the community, I’m convinced we can take this to a whole new level. So, this thread is for all of those with exotic visions of builds not seen before, of ideas that might seem crazy, and of cutting-edge techniques.

So you wanted a shiny new multitouch table on a strict budget, so you take some cash from the savings you’ve put aside for that huge TV you’ve been wanting. Why not have both? Why does your new multitouch platform be restricted to only a horizontal plane? Why can’t it be easily transitioned to a vertical format, without flipping the table over?

So let’s see it, folks. What’s the next big thing?

Bandpass Filter Simulation

2008-07-17T18:26:17-05:00

A tech support engineer at Omega Filters was incredibly cool and performed a computer simulation of bandpass filters for me targeting an 850 nm application. The simulation addresses the problems associated with light hitting the band pass filters at angles which I posted in this thread. The 850 CWL 10 FWHM is great when the blobs are near the center of the screen. However, as you move out toward the corners of the screen the blobs fade. This is because as light comes into the filter at angles greater than zero degrees the effective pass is shifted blue out of the range of the intended light pass. The 850BP10 simulation demonstrates this failure. To address the problem you can red shift your filter selection and increase the FWHM. This is what the 2nd simulation shows. The bold trace show a zero degree angle of incidence and the faint trace show 28 degrees.

Hello from Nevada (nu-va-duh!!) :D

2008-07-23T18:21:40-05:00

I just found out about Multi- Touch a few days ago.

I have no experience in any programing language.
Going into high school.
Am running on a very, very tight budget.
Just barely started to use Ubuntu Linux.

I’ve been browsing around the forums a couple days seeing all the cool technologies.
I would like to make my own table and have a few questions on all the different technologies involved. I would appreciate it if someone could answer my questions.
1. What are the different technologies?
2. What are the advantages of each technology?
3. Which is one of the best languages for programming(just an opinion)?

Thanks

Anyone using (or used) Java for multitouch?

2008-06-27T17:05:21-05:00

Is anyone using or has anyone used Java for a multitouch app? Particularly using the open-table.org software?

Tracing paper below screen. No silicon layer. Works fine. Am I missing something?

2008-07-23T09:07:03-05:00

Hey,

After some quite frustrating messing around I tried just placing tracing paper under my 12mm acyclic. It seems to work fine. I read there were some issues with slight differences between the place touched on the acrylic and the projection underneath but I haven’t encountered any of this. I tried the screen from each side as well i.e. calibrate it from one side and then try using it from the opposite side to see if there was any difference in the calibration, but couldnt see any.

My table is only a prototype (see pic) so I may well be missing something but this seems ideal. Before I put any projection surface on ive found its not “touch sensitive” but requires a small amount of pressure but adding the tracing paper underneath makes no difference to this. I guess with some more sophisticated systems this could be an issue though?!?

As im touching the acrylic I tend to use a bit of moisturizer on my finger but that seems to coat the surface after a short time anyway so you dont need it after a while.

Anyway just thought id mention it as seems a quick and easy way to get an up and running prototype,

DSI - Diffused Surface Illumination

2008-06-14T16:10:26-05:00

This technique is generally inspired by Tim Roth, but i want to make some changes ("enlighted" acrylic doesn’t looks good for me, because of price and it’s properties).

I have an idea, that frosted acrylic will work the same way. If we’ll use frosted acrylic for FTIR, so all the light will go thru frosted side (remember, FTIR), and the we’ll get the same effect, except no highlight to camera. Also “frosted film” could help. So, basically we’ll get almost uniform illuminated surface.

It is just an idea, but I’ll test it next 2-3 days, and will keep you updated:

Original DSI Article

ROLL-ON Silicone Coated Drafting Vellum

2008-07-06T19:53:21-05:00

I’m pleased that my technique for applying textured silicone to vellum is working for the people who have tried it.
Cheers!

In the interest of making this even easier, I’ve improved on the technique to apply the silicone.

I now thin it with Zylol at a 1:1 ratio, mix well, and pour it onto the vellum. Here’s the cool part that makes it easy-peasy.
I roll it out over the surface with a foam rubber paint roller like the ones they have at hardware stores.
The texture produced is micro-bumps on the surface. I applied two coats, and now the silicone layer is about half the thickness of the squeegie/fabric technique!

It produces blobs with a light touch, but it still needs a few more coats to be as sensative as the squeegie style sheet. With this technique of application, it’s even easier to get a good, even coat of silicone onto the vellum so building it up in several layers is not so hard to do. It just takes a little wait time between coats. I waited an hour on the first one. It felt like it was cured up pretty well after 30 minutes, but I gave it another 30 minutes to be sure it wouldn’t lift.

I think I’ll make more and do about 5 or 6 coats.

Here’s a how-to video I made:

[youtube]http://www.youtube.com/watch?v=vvO_lvyDGVo[/youtube]

You can clean the roller pretty easily with the zylol and a rag. Just get the roller wetted out with the zylol, then roll out the excess onto the rag. Dispose of the rag in a fireproof container or hang it to dry. NEVER put solvent soaked rags in the trash. They can self ignite.

Have fun rollin the silicone!