Re: bluetooth proximity
--- On Mon, 6/16/08, Tilman Baumann [EMAIL PROTECTED] wrote: AVee wrote: (...) There are a lot of reasons why this is not feasible. Sorry. I tend to agree, however, things might change if you add gps. You'd might just (...) That leaves only the 'exact measurement' to be solved. It might work, but the precision will probably still be far to low to be useable for anything. (absolute position...) But the relative position should be extremely high. (As high as DGPS can get) At least in theory. Thanks for thinking along. What I was thinking of, in a game setting, to use the phone as some sort of hack slash device. Given my opponent and me are withing reasonable proximity, she with -say- a spear-device, me with a sword or so. She could try stabbing me, while I parry. The devices have to calculate the hit ratio. Would a sound-code offer a possible solution? Could we measure some doppler effect with the built in microphone? And, on a side note... How impact proof will the phone be, might she try throwing her spear? :-P ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
W. B. Kranendonk wrote: --- On Mon, 6/16/08, Tilman Baumann [EMAIL PROTECTED] wrote: AVee wrote: (...) There are a lot of reasons why this is not feasible. Sorry. I tend to agree, however, things might change if you add gps. You'd might just (...) That leaves only the 'exact measurement' to be solved. It might work, but the precision will probably still be far to low to be useable for anything. (absolute position...) But the relative position should be extremely high. (As high as DGPS can get) At least in theory. Thanks for thinking along. What I was thinking of, in a game setting, to use the phone as some sort of hack slash device. Given my opponent and me are withing reasonable proximity, she with -say- a spear-device, me with a sword or so. She could try stabbing me, while I parry. The devices have to calculate the hit ratio. Would a sound-code offer a possible solution? Could we measure some doppler effect with the built in microphone? You'll be better off using the accelerometers... And, on a side note... How impact proof will the phone be, might she try throwing her spear? :-P ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
W. B. Kranendonk wrote: And, on a side note... How impact proof will the phone be, might she try throwing her spear? :-P The weakest link is the screen. :p -- Drucken Sie diese Mail bitte nur auf Recyclingpapier aus. Please print this mail only on recycled paper. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
Tilman Baumann wrote: Deamons that trigger events when a bloetooth device comes in range have already been implemented. In Ubuntu and Fedora, check out blueproximity -- you sync your bluetooth device with your PC, and set a proximity level in feet (1..30) and when the device goes out of range for a preset number of seconds, it launches a locked screen saver. When the device comes back into range for another preset amount of seconds, the screensaver is deactivated. It's pretty handy in secure environments -- I just implemented it yesterday with both my Blackberry and Samsung Blackjack2, and it works fine -- I haven't tried it with the Freerunner yet. I imagine someone could port the code to the OpenMoko platform easily enough... then you'd just need to pair the two Freerunners with each other. I don't know whether sword fighting would be feasible due to signal processing and calculating distance in a fast-paced environment. -id ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
Saw this at some mobile event: http://www.vimeo.com/875097 2008/6/18 Ewan Marshall [EMAIL PROTECTED]: W. B. Kranendonk wrote: --- On Mon, 6/16/08, Tilman Baumann [EMAIL PROTECTED] wrote: AVee wrote: (...) There are a lot of reasons why this is not feasible. Sorry. I tend to agree, however, things might change if you add gps. You'd might just (...) That leaves only the 'exact measurement' to be solved. It might work, but the precision will probably still be far to low to be useable for anything. (absolute position...) But the relative position should be extremely high. (As high as DGPS can get) At least in theory. Thanks for thinking along. What I was thinking of, in a game setting, to use the phone as some sort of hack slash device. Given my opponent and me are withing reasonable proximity, she with -say- a spear-device, me with a sword or so. She could try stabbing me, while I parry. The devices have to calculate the hit ratio. Would a sound-code offer a possible solution? Could we measure some doppler effect with the built in microphone? You'll be better off using the accelerometers... And, on a side note... How impact proof will the phone be, might she try throwing her spear? :-P ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
Ok, I just got this email twice. Something's definitely funky with the mailing list software. Someone asked to be notified if that happened again. Cheers Dave On Wed, 18 Jun 2008, john wrote: Saw this at some mobile event: http://www.vimeo.com/875097 2008/6/18 Ewan Marshall [EMAIL PROTECTED]: W. B. Kranendonk wrote: --- On Mon, 6/16/08, Tilman Baumann [EMAIL PROTECTED] wrote: AVee wrote: (...) There are a lot of reasons why this is not feasible. Sorry. I tend to agree, however, things might change if you add gps. You'd might just (...) That leaves only the 'exact measurement' to be solved. It might work, but the precision will probably still be far to low to be useable for anything. (absolute position...) But the relative position should be extremely high. (As high as DGPS can get) At least in theory. Thanks for thinking along. What I was thinking of, in a game setting, to use the phone as some sort of hack slash device. Given my opponent and me are withing reasonable proximity, she with -say- a spear-device, me with a sword or so. She could try stabbing me, while I parry. The devices have to calculate the hit ratio. Would a sound-code offer a possible solution? Could we measure some doppler effect with the built in microphone? You'll be better off using the accelerometers... And, on a side note... How impact proof will the phone be, might she try throwing her spear? :-P ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
W. B. Kranendonk wrote on 06/16/2008 12:24 PM: Hi List, I wondered, can two bluetooth devices ping each other and find out their distance or relative speeds? Not in the first place as some security tag to unlock my PC or house, but to use in a game-like setting. Imagine some live role playing game, where weapons not only are simulated using acceleration, but also their speed/distance relative to each other. Any ideas on this? Boudewijn ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community although I think that it is relatively unlikely to work.. sounds interesting! - just manage to plug a laser pointer into your neo, blow some dust into your room and start playing around with your new lightsaber ;) may the force be with you.. Georg ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
Hi, I don't think that's feasible. To measure (with 2 devices) you need two very synchronous clocks and a very exact measurement. Because the signal travels with approximately the speed of light (about 300.000 km/s), an error of 1µs is an error of 300m. There are a lot of reasons why this is not feasible. Sorry. David ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
On Mon, 16 Jun 2008 12:24:27 +0200, W. B. Kranendonk [EMAIL PROTECTED] wrote: I wondered, can two bluetooth devices ping each other and find out their distance or relative speeds? Not that I know of, but two cooperating Freerunners can exchange information about their GPS coordinates and measured acceleration. -- Alexey Feldgendler [EMAIL PROTECTED] [ICQ: 115226275] http://feldgendler.livejournal.com ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
W. B. Kranendonk wrote: Hi List, I wondered, can two bluetooth devices ping each other and find out their distance or relative speeds? Very unlikely. But some bluetooth devices can tell you the signal level of any peer. With that, you could aproximate the distance. Would be interesting if our device can do this. Not in the first place as some security tag to unlock my PC or house, but to use in a game-like setting. The first option would at least work in any case. One could make hint location based subsystem by detecting certain stationary bluetooth devices. Deamons that trigger events when a bloetooth device comes in range have already been implemented. -- Drucken Sie diese Mail bitte nur auf Recyclingpapier aus. Please print this mail only on recycled paper. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
On Monday 16 June 2008 14:40, David Kepplinger wrote: Hi, I don't think that's feasible. To measure (with 2 devices) you need two very synchronous clocks and a very exact measurement. Because the signal travels with approximately the speed of light (about 300.000 km/s), an error of 1µs is an error of 300m. There are a lot of reasons why this is not feasible. Sorry. I tend to agree, however, things might change if you add gps. You'd might just transmit your own speed and location, although you will probably hate the precision of that without DGPS (which may never work on the Freerunner) and if may not work al that well indoors. But GPS could also solve the first problem you mentioned, it can provide the same clock to the two device. That leaves only the 'exact measurement' to be solved. It might work, but the precision will probably still be far to low to be useable for anything. AVee -- Everything should be made as simple as possible, but not simpler. -- Albert Einstein ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
One can also measure the signal strength. I don't know how accurate that is. KDE has a tool that locks the desktop if you (and your bluetooth phone ofcourse) are to far away. Peter Op Monday 16 June 2008 15:59:45 schreef Alexey Feldgendler: On Mon, 16 Jun 2008 12:24:27 +0200, W. B. Kranendonk [EMAIL PROTECTED] wrote: I wondered, can two bluetooth devices ping each other and find out their distance or relative speeds? Not that I know of, but two cooperating Freerunners can exchange information about their GPS coordinates and measured acceleration. signature.asc Description: This is a digitally signed message part. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
Re: bluetooth proximity
AVee wrote: On Monday 16 June 2008 14:40, David Kepplinger wrote: Hi, I don't think that's feasible. To measure (with 2 devices) you need two very synchronous clocks and a very exact measurement. Because the signal travels with approximately the speed of light (about 300.000 km/s), an error of 1µs is an error of 300m. There are a lot of reasons why this is not feasible. Sorry. I tend to agree, however, things might change if you add gps. You'd might just transmit your own speed and location, although you will probably hate the precision of that without DGPS (which may never work on the Freerunner) and if may not work al that well indoors. But GPS could also solve the first problem you mentioned, it can provide the same clock to the two device. That leaves only the 'exact measurement' to be solved. It might work, but the precision will probably still be far to low to be useable for anything. I don't think so. What you get is effectively something like DGPS. Both receivers (while being near each other) receive the same skew/offset. Both will have wrong readings for the absolute position. But the relative position should be extremely high. (As high as DGPS can get) At least in theory. DGPS works just this way with the difference that with DGPS one receiver is stationary and propagates a correction signal to all receivers nearby. -- Drucken Sie diese Mail bitte nur auf Recyclingpapier aus. Please print this mail only on recycled paper. ___ Openmoko community mailing list community@lists.openmoko.org http://lists.openmoko.org/mailman/listinfo/community
