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Get iOs position within a house or yacht

Dear all, I'm thinking on a new way of "multiroom" audio, since the iphone can run the Apple Remote app to control itunes (or other similar app), I'm thinking on a way to understand in which room that iOS device is in and automatically route the audio to that room. A sort of RFID attached to it with a receiver in any room, or a sort or blutooth gateway in any room.
The Antherus will fit this need but the transmitters are too big.
Any idea on an altenative solution? The idea is that the user hit play without any extra interaction with the system.
The great will also be if we can get this info from the wifi access points, like get the mac addresses of the attached clients....



  • DHawthorneDHawthorne Posts: 4,584
    We toyed with the concept for a while, but came to the conclusion that it was really too fiddly to get the RFID to work properly and consistently. It's difficult to have both full coverage of an area and not have an overlap that would make the sensor think it's in the wrong room.

    What's needed is something like a GPS (only local though - House Positioning System?) system with fine enough resolution to be able to define the rooms properly, yet cover the entire controlled area.
  • John NagyJohn Nagy Posts: 1,714
    How much is the customer willing to spend to keep from having to touch the room name they want? And if they want to control a room they aren't in at the moment (or the one they really are in that the ID failed on), they will still have to touch a button.

    How about a iPad in every room, already defaulting to controlling that room? Probably would cost nearly as much as your tracking system.
  • criss87criss87 Posts: 32
    Theese are all correct points but yacht clients are sometimes very spoiled.... (hope my english is correct...)
    I got one client from russia that when he get off from his boat he rent other boats to see what other people have ( not only for A/V system of course...) and then he ask always to add more on his own one.

  • jimmywjimmyw Posts: 112
    I am about ~90+ hours into this on my own to try and get granularity out and correct the triangulation formulas, and requires exact knowledge of where every mode is located on an x,y,z plane and having the job mapped out in the same way, while this will get you close variances in rf interference from other devices and materials will cause some stray, also something to think about, object momentum and path prediction come into play, none of this is something that an NI could even begin to approach, I am using a core i7 975 with 8gb of ram to do all this.
    Heres some basics to start

  • annuelloannuello Posts: 294
    Would an IR transmitter on the iOS device be acceptable? Line-of-sight might allow you to determine what room the device is in, assuming there are no glass walls. I would still use WiFi for the main comms transport to the iOS device, and have a background app which sends out an IR beacon every XX seconds (or faster when the iOS device is moving). Given that you are on the high seas, may need to set some thresholds or hysteresis on the accelerometer data to take into account normal pitch/roll of the hull.

    These folk have released an SDK for their IR transmitter, allowing you to write your own apps.

    Just a thought... There are other versions that run off the 3.5mm jack, but I couldn't find matching SDKs in my quick search.

    Roger McLean
    Swinburne University
  • jweatherjweather Posts: 320
    If you use Cisco APs and controllers, you can add Cisco's Location Appliance to get a real-time feed of device locations. This would be a $20k+ project depending on how many APs you need, though...

    Personally, I would probably look into designing some sort of Bluetooth proximity sensor that could be placed in each room, or an RFID system with passive tags that could be integrated into an iPhone case. You'll need at least one sensor in each room that way, though.
  • criss87criss87 Posts: 32
    Yes, i think the blutooth or rfid one should be the one to try, i will search for a bt gateway

  • Jimweir192Jimweir192 Posts: 502
    Have a look at


    This should do what you need
  • criss87criss87 Posts: 32
    I just wrote them an email to know more about, yes i think it will do the trick, as soon as i will know somethink i will post it.
    Many thanks for the help!!

  • PhreaKPhreaK Posts: 966
    If you can use bluetooth it will prevent the need to start attaching other devices to your interface which will be much neater. Triangulation is one possibility, however as others have mentioned interference can make this somewhat troublesome. jimmyw solution using path predication sounds awesome but it will involve setting up a separate system for processing to offload it from the NI (not necessarily a bad thing as it will give you actual position - just a metric but load of work).

    Now, if you're only wanting to identify what room you are in rather than an explicit location you could think about this a slightly different way. Rather than playing with the placement of your sensor, think about the placement of the receiver. By placing two at each room entry point (one on each side of the doorway) it should be possible to identify movement direction between rooms. Add in a little bit of logic to filter out room switches if the user is simply near the doorway (i.e. require acquisition to move from one receiver to the other and hold there for x etc). From there you can track current room. Once you got the infrastructure in place this will then function with as many devices as the receivers can acquire.
  • jimmywjimmyw Posts: 112
    PhreaK wrote: »
    Once you got the infrastructure in place this will then function with as many devices as the receivers can acquire.

    If you are using an RFID solution that should work, the nice thing about bluetooth is getting an RSSI(5 actually) per read and going that way, you could do the same with bluetooth and just call it good that they are in that room if the RSSI hits a certain point, I have a demo in our shop using 12 usb bluetooth dongles behind wallplates, and I am able to do 5 RSSI readings per device, up to 15 devices per node, per transmission, 2 transmissions a second. I have been able to use a micro ATX form factor EPIA pc (2.4 ghz) to run it and send just a room location to AMX, and a room prediction(if applicable) if AMX sees that, it starts a d/c timer for the old room and kicks on the new room (if unused). if the prediction is false and they change paths the d/c timer is either canceled, ( if they stayed) or the room prediction is updated and amx kicks on the new room. I have done a demo in a clients house, the coordinating PC had to get beefed up several times to handle the full scale test, 80 nodes * 5 readings * 15 devices(max) * 2 readings a second + calculating speed and direction based on last 3 readings + pulling XYZ from SQL server + sending to AMX. I would say I have about another 30 hours to finish it. Anyone interested in beta testing? (requires Ubuntu desktop pc + compatible bluetooth dongles)
  • criss87criss87 Posts: 32
    I can built an ubuntu pc, no problem, which dongle i should buy?
  • criss87criss87 Posts: 32
    To easily run in a house a BT to ethernet should be best I think... Probably the blip one can fit this need.
  • criss87criss87 Posts: 32
    The Blip is a complete system that run with their own software, I explsain them what I need to do, they say that your system can easly do this but after asking for a quote they never reply my anymore.
    So I end up by buying 3 Bluegiga BT access points, now I will try to make them working in the free time...

  • New Problem! I test the Bluegiga Access Points and they work as a charm, you can telnet into them and get the RSSI of all the discoverable devices..... yes, discoverable, this is the problem!
    The iPhone/iPod will be "Visible" only while in the Bluetooth control panel! then when you exit, you lost it....

    Now I will check if thru the iOS sdk you can make the Bluetooth discoverable while a custom app run in Background
    But I know Apple....

    Any help....

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