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joeliethegoalie
Nov 7, 2007, 02:23 AM
Is it possible to create an app that uses the accelerometer to turn the Touch into a compass?

I'm guessing no but thought I'd ask as it would come in handy. I doubt there'll be a magnet coming in the next update...



Big-TDI-Guy
Nov 7, 2007, 02:27 AM
I thought the touch has flash based memory, I wonder why they would put in an accelerometer?

Also - while not completely understanding the inner-workings of a solid-state accelerometer - I don't think an accelerometer would do much to help in pointing north.

tubechallenger
Nov 7, 2007, 02:29 AM
Presumably to allow you to turn it over to get Cover Flow. ;)

gr8tfly
Nov 7, 2007, 02:31 AM
The accelerometer doesn't sense magnetic fields. Handy idea, though.

Big-TDI-Guy
Nov 7, 2007, 02:49 AM
Presumably to allow you to turn it over to get Cover Flow. ;)

First off, I being a retard, wasn't even thinking of the Touch when I posted - I was envisioning the Nano.

Second, that does pique my interest. I would think an accelerometer would give flaky performance if you rotated too slow, or if you spun around when holding it. (G-forces would throw it off) Maybe they use something similar to a mercury switch. Or a combination thereof. I'll have to (#*$ with my iphone, and think of it when I'm less tired.

gr8tfly
Nov 7, 2007, 02:56 AM
First off, I being a retard, wasn't even thinking of the Touch when I posted - I was envisioning the Nano.

Second, that does pique my interest. I would think an accelerometer would give flaky performance if you rotated too slow, or if you spun around when holding it. (G-forces would throw it off) Maybe they use something similar to a mercury switch. Or a combination thereof. I'll have to (#*$ with my iphone, and think of it when I'm less tired.

They're solid state sensors, but yes, if you create acceleration by spinning, they'll be affected.

Moving the sensor slowly doesn't matter. It's sensing the direction and amount of acceleration. edit: (there's a sensor for each axis required)

edit: FYI - Apparently all three axis are in a single package. Hard to keep up with the latest. ;) I have a single axis "gyro" on my r/c helicopter, but it's a few years old. Its single sensor was probably in a larger package than the iPhone/iPod Touch 3-axis device.

MonM
Nov 7, 2007, 07:53 PM
There is no possible way that I can think of using the accelerometer. However it is possible to get a pretty accurate reading using the sun and the hands on a watch.

watch as a compass (http://www.time4watches.com/1.%20Bradley%20articles/using_a_watch_as_a_compass.htm)

I suppose you could whip up a simple app with a full screen clock face and a representation of the sun where the hour hand should be. Not quite as easy to use, but it would get the job done.

PMB
Nov 7, 2007, 08:14 PM
sensors in the installer.app let you do that, not a compass, but sort of, no direction, it does tell you what up is though

assuming that your pod is jailbroken

cwolves
Nov 7, 2007, 09:35 PM
nice idea but completely impossible. The touch's 3 accelerometers are all gravity based, meaning that they all know which way "up" is. That's all they know. By putting them at 90 degree offsets to one another, you always know which way up is...but you can -always- rotate the touch on the up-down axis without the touch knowing about it...it does NOT have an internal gyroscope.

Anuba
Nov 8, 2007, 02:42 AM
One day in the not so distant future, I'm sure the iPhone (and perhaps the iPod Touch) will have GPS, which in turn will allow it to work as a compass. (Not that I know why anyone would want a compass when there's GPS... that's kinda like buying an iPhone for using it as a string can phone).

gr8tfly
Nov 8, 2007, 03:28 AM
One day in the not so distant future, I'm sure the iPhone (and perhaps the iPod Touch) will have GPS, which in turn will allow it to work as a compass. (Not that I know why anyone would want a compass when there's GPS... that's kinda like buying an iPhone for using it as a string can phone).

Close - but still no. GPS alone won't work as a compass, unless you are moving.

Kardashian
Nov 8, 2007, 03:57 AM
Called that number last night - had a lovely girl but she didn't seem to know jack.

She said if I called back this morning they could transfer me to Newport - and ask nicely if they could bump it along.

The woman who I just spoke to now said she would not transfer me as it was pointless because she could tell me everything I needed to know. :confused:

She told me they received it yesterday - and the step now is to either pass it on to an examiner who will pass it on for printing, or it will go to an interview department?

God. I hope it comes back soon. Why can't someone at MR work there :(

gr8tfly
Nov 8, 2007, 04:10 AM
Called that number last night - had a lovely girl but she didn't seem to know jack.

She said if I called back this morning they could transfer me to Newport - and ask nicely if they could bump it along.

The woman who I just spoke to now said she would not transfer me as it was pointless because she could tell me everything I needed to know. :confused:

She told me they received it yesterday - and the step now is to either pass it on to an examiner who will pass it on for printing, or it will go to an interview department?

God. I hope it comes back soon. Why can't someone at MR work there :(

How apropos. Do you need said compass? Me thinks thee is lost.

EIther that or I am. It's late and I'm getting early, So I could have definitely missed something.

koobcamuk
Nov 8, 2007, 04:12 AM
Is it possible to create an app that uses the accelerometer to turn the Touch into a compass?

I'm guessing no but thought I'd ask as it would come in handy. I doubt there'll be a magnet coming in the next update...

Compass? You'll be reading the stars next... :rolleyes:

Genghis Khan
Nov 8, 2007, 04:43 AM
No...a compass requires something long, magentic and on a low friction point of rotation

first off, we have the accelerometer...that only senses the movement of the Touch itself

anything magnetic?...only the electro-magnetic fields created by the thing itself

so basically, no hope of a compass...however i doubt anyone would ever use one:rolleyes:

Big-TDI-Guy
Nov 8, 2007, 08:56 PM
While you could definitely get GPS function out of the iphone via the cellular radio, it couldn't accurately tell you a heading, until you've already moved around a good bit. (then it could see which direction you're going in - providing you were walking in one direction) But to be stationary, and have a "here is north" signal - not as easy.

Also, the radio in the iphone isn't designed for any hi resolution triangulation (it's designed for data and voice), so it wouldn't be anything I would trust driving around.

You could buy one of those itty-bitty compasses, with the adhesive on the back side, and glue it to your touch.

Or join the Boy Scouts of America - they could probably teach you how to find your heading without anything - and even give you a merit badge for it.

joeliethegoalie
Nov 9, 2007, 01:49 PM
Thanks for your responses. Looks like the compass is a no-go, for now anyhow.

It would be helpful though. The Touch-as-compass idea occurred to me a couple of weeks ago while I was visiting a new (to me) city and trying to get oriented. The sun was down and I can't read the stars (and I think I'm probably too old for the Boy Scouts, as one poster suggested).

Overall though, the Touch performed great during its first real field test. With all the jailbreak features added, it worked perfectly as a PDA for the conference I was attending, and I had easy web and email access pretty much everywhere I went. A lot more convenient (and fun) than a laptop, that's for sure.

Thanks again...