I'm getting started with Arduino and want to make a portable, slim, gps tracker that gives real-time updates and activates either when the object leaves a "safe zone" or when it's texted by a phone.
A stretch goal is for the device to emit a high pitched tone, or other alarm sound notifying people passing by.
It seems I need the following parts:
- TinyDuino $20 - Eventually, only a "lilyboarded" ATMEGA328 chip for $3.
- GPS/GPRS module $60 - Obtains Positional Data/Connects to internet to relay information in real-time.
- Antennae X2 - Two needed for GPS and GPRS?
- SIM900A or SIM809 - Allows texting and 2g or 3g data using pre-paid SIM cards. Essentail for real-time updates and text abilities.
- Power Source - 3.7V Lithium Ion battery
- Container - TicTac for now.
- Misc. case parts
- Speaker module - Optional
Questions: 1. How to make it cheaper?
How can a device like this one be only $13 and do the same things? Is there a cheaper way to do this or is it just because they are sourcing parts directly from cheap factories in China? It's tempting to buy one and reverse engineer the pieces...
Do I REALLY need to by two antennaes?
Is there a way to use even less parts to get the cost down? I'm asking because there may be devices that accomplish similar things I'm not aware of as a newbie :)