How to send GPS coordinates from android phone to microcontroller?
The ideal situation here would be to have a serial port over USB connection between your Android phone and your PC, and to stream NMEA across it from the phone. Unfortunately Android doesn't support USB in such a way natively. GPSTether is a "hack" using the adb forwarding debug bridge in order to create the link between phone and PC, and then reads the NMEA from the location manager and sends it over the TCP/IP link created by adb forwarding. If you are finding GPSTether too buggy, you really only have two choices either a) implement a version of GPSTether yourself, or b) come up with a different method for doing this. Both will involve quite a bit of coding. For b), you might want to consider - writing NMEA to a file on the phone while it is connected to the PC as a USB Mass Storage device, and reading updates to the file from the PC regularly. Or perhaps you could get a bluetooth dongle for your PC and "tether" the phone to the PC over bluetooth, by creating a bluetooth COM port connection for the GPS using something like the Android app BlueNMEA. Or you could copy an FTP client program, and write the file to an FTP server on your PC over a WiFi connection (which would allow you to have the phone on the other side of the world from the PC).
How do I make a vehicle tracking app for my college students to track buses?
As far as I have understood, your requirements are to track buses of your college by using mobile phones which will be present in the buses, am I right?To be tracked the buses needs to have a GPS device which can upload their location to a server(I'll get back to it in a moment). If you're choosing a mobile phone, you can create an app to get location in Longitude and Latitude and upload to the server using APIs. The Server can be created in any backend framework. You can choose to use php+MySQL, Asp .net+MSSQL, Node.js+MongoDB or any other framework of your choice. You need to have an API module which will accepts and replies to POST requests from Mobile app and does CRUD operations on Database.Now the thing which is not clear to me yet is how you're going to display the results? Will you be having a web admin panel or will you be having an admin app or an admin module in the app to get the information?Whatever you choose, you can use free Google Maps API to show the locations as markers and can calculate distance between them using the same API. The lag between the movement of bus and publishing the data on the admin panel would depend upon the network. For faster communication, you can choose to have a direct socket with the server without having any network protocol such as HTTP in between.The second best option would be to use XMPP which is used for real time chat messages (Whatsapp, FB messenger, GTalk etc. uses it), but can be used in any other way whenever fast communication requires. I have used it in a cloud call center app and it worked great. You'll need to have an XMPP server such as OpenFire or Ejabberd deployed on your web-server and will need an XMPP library on your phone. Asmack is a good library for Android while XMPP Framework is more than enough for iOS.In any case you'll need a working web server and need to learn the corresponding programming language. PS: Let me know if you still need more details on any of the term.Happy Coding!
Can a GPS tracking device work without SIM card? What is the principle on which it works?
Absolutely a GPS can work without a SIM card. Actually the GPS and the SIM don’t have any overlap in what they do in a device. The GPS receiver calculates a position. But the GPS receiver is just a receiver, it cannot send information. That’s where the mobile phone technology comes in. Sometimes that requires a SIM card but it can also be accomplished with certain components that negate the need for a SIM card while still sending data via a mobile phone network. At my company, Telemetry Solutions, we build GPS receivers that use various radio technologies to send GPS location information from the device to the users. We also use satellite modems to transmit GPS location information globally.