Truck GPS Data Trasmitter

Projects General Guidance
1

Hi,

I have build a Arduino based data GPS data transmitter.The device takes the GPS co-ordintates and sends the same to the Web though GPRS connection.
It is basically using Arduino Mega 2560,GPS module,SIM900 based GPRS module.The device is powered using the Truck battery itself after some smoothing of the voltage I have given 9V supply individual supplies to these three devices.It did work for 3 days straight sending me the co-ordinates once in 15s to my queue.The truck has been moving around the city only for the entire span of three days and the signal GPRS seem to bit good.

On the fourth day,the truck went to some remote place and the GPRS signal seems to be weak in that area.The msgs stop intermediately and starts re-transmission automatically.I did observe the following.

  • The GPS device is able to get the fix and it is working fine
  • The GPRS signal is weak(Could see in the mobile),but still when I call up the device ,I am able to get the ringing ,I am trying to establish that the GPRS module is responsive.
  • When I restart the Arduino,I am able to get the messages again.But after few minutes it stops again(No pattern in the stopping).
  • When I check the Arduino's Serial through which the device logs about itself,in a computer.The logging seems to be normal.I am trying to establish that the Arduino program is not hung.
  • Arduino Mega Is getting heated up than normal.

What could possibly be going wrong here? only the GPRS signal ?

2

I presume you meant to say that the Mega is heating up MORE than normal. I can't think why that should be, just because the phone signal is weak.

I'm not very clear about your electrical connections - can you post a diagram (photo of a pencil sketch) with part numbers included.

Phones use considerably more power when the signal is weak.

You haven't posted your code but you may need to include in it provision for loss of phone signal so that it can re-establish connection when the signal improves.

...R

3

Hi Robin,

The sketch of my connections is attached.I do have a check for the GPRS connection before sending the message.That seems to work.

Connection.jpg
Connection.jpg653×510 33.9 KB

4

Put a better antenna on your SIM900 module!

// Per.

5

I have put thing similar to this..

a741005+.jpg
a741005+.jpg787×1200 97.7 KB

6

baluvignesh:
The sketch of my connections is attached.I do have a check for the GPRS connection before sending the message.That seems to work.

Nice clear diagram. Nice simple arrangement. The XL4005 seems to be capable of providing 5 amps so there should not be a power supply problem.

I presume you are using HardwareSerial ports on the Mega, and not SoftwareSerial.

What happens (in your code) if it detects a signal and sends a message but the signal fails before the message is sent?

Post your code (hope it is not too long) and also a description of how it is supposed to work.

...R

7

Hi Robin,

I guess for the Scenario you have asked,the message will be lost.In the next loop run,the new co-ordinates will be sent.
Right now ,the truck has moved and the data is getting logged now in the Queue.I think it is a problem with the GPRS signal only because of the remote area.

8

baluvignesh:
I guess for the Scenario you have asked,the message will be lost

It wasn't that part of the problem I was referring to. That is an external issue.

What happens within your system when that happens? For example does it block waiting for a "success" signal that never comes?

...R