Microsoft Surface has the capacity to download data from cameras, etc., wirelessly (I assume using bluetooth). Easy, but it only does this when the device is on the table-top.
One way of doing this is to have some sort of location sensor for the camera or other device, and then when a shadow is made in approximately the right place on the screen, it is assumed that the device is sitting on the screen.
But is it possible to triangulate a device’s position with bluetooth? How else could I achieve the same affect?

i think m$ makes use of Wi-fi. but bluetooth is also a possibility. I believe the camera/phone/etc is tracked as fiducials to make it possible to detect when the device was put on the screen and where (and what type of device)

for bluetooth i would do this:

when the application starts, detect all bluetooth devices.
then when someone puts something on the table check for any new bluetooth devices, if a new device is found, it’s probably the device that was put on the screen.
connect to that device and there you go.

problems with this approach:
if the device was in range when the application started it won’t be detected as a new device.

a solutions to this would be to have a type of ‘barcode’ on the bottom of the device containing something like the bluetooth name or device model so that you can check in the list of ‘in range’ devices for the device that was put on screen.

EDIT:

“In addition to recognizing fingers, Surface can recognize inanimate objects. Microsoft has developed a 3/4” square tag called a “domino” that can be attached to objects so that Surface can interact with them on the fly. Instead of relying on RFID, the domino tag uses dots to encode its information (hence the name). There is a single dot in the center of the tag, three dots on one side for orientation, and space for eight more dots that are read as data. Essentially, it’s a one-byte data tag.”

taken from here

Would it be possible for device to “learn” it first. Like taking a picture of it?
After you have teached the devices look for the computer it will recognize it from the picture.
If there is many of the same kind of devices you could simply use IR-active pen or something to add random dots to the bottom of the device…

it would be possible with some AI,like a neural network.but that would involve training the screen. and many phones has a similar shape.

so ir dots might be better.

do you think Bluetooth triangulation would be possible in this case ?

1 - detect a new shape
2 - Start Bluetooth Detection
2.1 - Start Triangulation
3 - compare shape coordinat with the bluetooth one
4 - if there close enought assume thats the one, in case ask the user to confirm

I think the best way to track cell phones/PDA’s is with fiducials.... I’m working on a prototype where a fiducial is loaded on the cell phone screen, and you place the phone face down on the screen and the camera tracks the pattern.... yes i know, while putting a phone face down is not intuitive it’s technically easier to implement.... screens dont emit that much IR light, so im hacking the screen itself.....

It would be useful and impressive if we can have “spill over” interaction support in touchlib… touchlib can id and track fiducials, and then you can use any program for bluetooth transmission (as a conventional comport).

yeah I though about that, and yes it’s easy, but it’s also crap for interaction as you say.
but what could be a little bit more intuitive would be to :
-detect a new BT device
-send it a Fiducial marker
-the user put the phone on the table (screen looking to the table)
-computer finds the fiducial and says “ok in this position I got this BT device”
-draw a circle around the object
-ask the user to flip his phone INSIDE that circle if he wants to
-switching to object (shape) tracking mode (as in vvvv)

cuz anytime you will send or recieved files, you will probably have to confirm on your phone or need to see the sreen for whatever you need.

that was my idea, and that’s the way I’ll do it if BT triangulation is impossible

what do you mean by “spill over” ?

"spill-over interactions” is a metaphore for when, for example, you have something loaded on your cell-phone or pda (a website, an image, a video, a program, spreadsheet, blah blah) and you approach a table, you can “spill” the content on to the large screen by putting ur device on the table.

that would be really sweet !!!
Are you working on it ?

the Microsoft Surface probably uses some sort of identification method for each type of device sort of like a bar code that win you set it on the table it will create a specific shape or pattern on the table so win the tables camera reads the pattern it runs a program or something to find the device and preforms the spill-over interactions this would problems be put on the product as like a priced take or a sticker on the back of the product so it can be easily removed

the problem with your guises plan is if there were more than one blue tooth item around or wifi it would not know what one to connect to that is why there needs to be some sort of id method to id what is on the table

like donovan has stated

Here is visual proof that M$ Surface uses fiducial markers on the bottom of camera and cell phones. 

I thought that since the system use a physical recognition, it would be like nima said or something not based on some kind of modification of the device (sticks, IR markers...).

Of course this is perfect for the usual user but for a new user it is different, and for this one I think an other kind of input is more interesting (write a letter where he is about to put his device. If the device is moved, he enters the letter once again and it’s ok. The first recognition is done by validating the connection via bluetooth).

It was already known that MS uses fiducials , they just call them dominos.When the table sees that a certain domino has been placed on the table it initializez a wi-fi or BT connection to the device indicated by a certain fiducial and begins pulling files and displaying them around the fiducial creating the spilled over effect.

MJ is curently working on this , hopefully he will have succes in replicating it.

i found this talking about they rfid techs.

http://www.rfid-world.com/news/205920616

I wasn’t sure whether to write this in this thread of the RFID sticky.  But here I am.

Why not use a combination of RFID and BT or WiFi?  It would be pretty hard and expensive to try and triangulate a phone, etc position with BT and let’s be hoenst, who wants horrible little stickers on the bottoms of their devices for an MT device to look for?  Plus surely that would only work for a DI set up?

So, use RFID to find a device that is in range (i.e. placed on the table).  RFID is fairly close proximity, so you could set up an RFID reader with it’s active RF field within a very small radius around the MT device.  So for example, the field would just reach out to just above a MT coffee table surface.  That shouldn’t be too hard to do with correct sensors and power levels.  Just turn the gain up or down.  Or hell, you could have a small “hot zone” around the table so it picks up it has a possible device it can connect to, as it could just be an ID card and not a phone or camera, etc.

Then once it knows there is a device within range it can look for a BT or WiFi enabled device.  Now you would have to pair the devices the first time you use it, but let’s face it that’s not hard and there after they can just connect automatically.  Then through BT or WiFi it grabs the data info (pics, audio, etc) and spits it out across the screen so you can play with it.  You don’t even need to transfer anything, just get the data information and transfer the actual files only when needed.  So for a transfer or to play a video or something like that.

Connection to the device is then automatically ended when it goes out of RFID range.

Advantage of using a combo is that from my understanding of RFID, the point is to identify a device (embed the RFID and BT and WiFi MAC addresses with the same address) and then carry out an action.  So in theory it should be pretty straight forward.  Detect > initiate connection > Pair if needed, otherwise sync together > manipulate data > disconnect when no longer in RFID range.

Medd