[07.07.2009, v 1.3.1] Astrolabe - SMS your GPS position

[6ITdtvFQqY]

Download. Simply decompress it and copy it on your Windows Mobile 6 device and run it. (Works on my Polaris.)

Details

Source code



Description

Use your PDA to acquire your GPS position and send it through an SMS.

The GPS position is update every 5 seconds (in order to conserve energy).

SMSs can be sent automatically at regular time intervals.



Do you like hiking?

What if you go out in the wilderness and have an accident? How do you direct a rescue team to your location?

You can use Astrolabe on your PDA to acquire your GPS position and send it through an SMS to your friends / parents / children / rescue team.


Privacy

SMSs are not encrypted, so anyone who tracks your phone number can tell your precise position by reading the SMSs with your GPS position.

However, it's debatable whether this is relevant because if someone tracks your phone number, they may already know the position of your phone in the communication grid.



Power saving modes explained


The following power saving modes are available: none, manual, auto.


None

In this mode there is no power saving. The application and the GPS are running even if the PDA is in standby.

GPS positions are retrieved as soon as they are available and are automatically sent through SMSs as soon as it is mandated.

Warning: In this mode, the battery is drained quickly (because keeping the GPS active requires a lot of power). Therefore, the "Auto" power saving mode is active by default.

Use this mode only when GPS position availability is critical.


Manual

In this mode the power consumption is the same as if the application (including the GPS) is not running.

However, you must keep your PDA on in order for GPS positions to be retrieved and automatically sent through SMSs.

Use this mode only when power consumption must be at minimum.


Auto

In this mode the application is running all the time, but the GPS is sleeping most of the time.

Once every 30 minutes, the GPS is awoken for maximum 5 minutes in order to get a GPS position and automatically send it through SMS. When a GPS position is available, this timer is reset.

In this mode, since the PDA sleeps most of the time, it may miss the narrowest chance it may have to get a GPS signal. In order to be sure that GPS positions are retrieved and automatically sent through SMSs, you must keep your PDA on.

Warning: Do not rely on the ability of a PDA in standby mode to automatically acquire a GPS position in (maximum) 5 minutes. Check this yourself!

Use this mode in most cases.

Tests showed that in this mode the battery (of a HTC Polaris, 1350 mAh) would be depleted in about 16 hours, if no GPS signal is available; if there is a GPS signal, the autonomy should be greatly increased (an informal test indicates more than twice the autonomy). Without power saving, the battery would be depleted in about 6 hours.

[Ather]

Do you like hiking? What if you go out in the wilderness and have an accident? How do you direct a rescue team to your location?

what if there isent any signal?

(joking..)

Nice app btw

[6ITdtvFQqY]

If there is no signal, the program waits until it acquires a new GPS position. Then, a new SMS is sent within (generally) 5 seconds.

(Of course, if the repeat time is X, the SMS is sent only if more time than X has passed since the last sent SMS.)



Note: Keeping the GPS active drains the battery quickly.

[tahdor]

Originally Posted by 6ITdtvFQqY If there is no signal, the program waits until it acquires a new GPS position. Then, a new SMS is sent within (generally) 5 seconds. (Of course, if the repeat time is X, the SMS is sent only if more time than X has passed since the last sent SMS.) Note: Keeping the GPS active drains the battery quickly.

I hace seen many programs like yours, almost all drains battery when there is no GPS signal (inside buildings). Only one programs deals it better, but that has many other issues. One way to stop draining the battery is to read 'N' (say 50) number of NMEA messages from GPS and then turn off GPS for about 'M' (5 - 15) minutes. Then try again. This will save lot of battery. May be you can try implementing it.

[6ITdtvFQqY]

You can download a new version which has 2 new features.

You can see the trail of GPS locations where you were. The trail is updated once per minute.

A power save mode is available. If this mode is active, the PDA's power consumption is the same as if the application is not running; however, you must have your PDA on in order for GPS locations to be retrieved and automatically sent through SMSs.

Warning: Keeping the GPS active drains the battery quickly. Therefore, the power save mode is active by default.

Download

Details.

[6ITdtvFQqY]

Originally Posted by tahdor I hace seen many programs like yours, almost all drains battery when there is no GPS signal (inside buildings). Only one programs deals it better, but that has many other issues. One way to stop draining the battery is to read 'N' (say 50) number of NMEA messages from GPS and then turn off GPS for about 'M' (5 - 15) minutes. Then try again. This will save lot of battery. May be you can try implementing it.

As you can see, I've implemented a manual power save mode.

In theory, an automated power save mode can be implemented, where the GPS is woke up every 30 minutes to get a location and then sent back to sleep. However, I have no idea what that would do to the device, that is, waking it up every half hour and then shutting it down.

But most importantly, if a GPS location can't be retrieved, what would the device do? The user could be sleeping in a motel for the night (or move through caves or canyons) and the walls could block the GPS signal. Should the device keep trying and thusly consume energy (for how long?), or go back to sleep and miss even the smallest chance of getting a GPS location in those 30 minutes?

An automated power save mode is in conflict with the criticality of having a GPS location any time it is available. Of course, if the device has no power this becomes irrelevant, so a power save mode is necessary. But it's important for the user to understand what's going on.

The current manual mode allows the user to understand that and allows the settings (especially the trail) to remain active all the time. For the moment I consider this to be the best solution.

[doco76]

Hi,
Your program i very interesting, it will be great to manage the accelerometer
and send a SMS when the phone do not move or when it goes from vertical to
horizontal position.

What do you think of that?

Regards

[6ITdtvFQqY]

Originally Posted by doco76 send a SMS when the phone do not move or when it goes from vertical to horizontal position.

In what context would someone use such a feature? I mean, what does an accelerometer provide that the GPS's altitude does not?

I guess an SMS could be sent as soon as a significant change in altitude occurs (because this could indicate a fall).

[sinancetinkaya]

Very good idea, thank you
I know you're still developing this program,

Can you add customizable SMS feature? I might need to send an sms in my native language.

And

The program will send SMS automaticaly to Predefined Numbers feature would be great

May it be easy

[6ITdtvFQqY]

I know you're still developing this program

The development is actually frozen. I am just implementing critical stuff, like power saving, and doing bug fixing.

Can you add customizable SMS feature? I might need to send an sms in my native language.

You can simply send a normal SMS. I'll add a "copy GPS position to clipboard" feature to go with that.

The program will send SMS automaticaly to Predefined Numbers feature would be great

SMSs are sent to a predefined agenda contact. Someone who wants to send SMSs with his GPS location should normally do so to a regular agenda contact, so he'll already have an agenda contact or can setup one anytime. What particular usage would there be for an SMS sent to a phone number instead of an agenda contact?


I'll have a new version by tomorrow (if tests are okay) with multiple power saving modes: none, manual (as is now), automatic (where the GPS is automatically woken up to get a location - 5 every 30 minutes). I'll include the "copy GPS position to clipboard" in there.