I have this project am doing and am stuck at interfacing two GPS modules to one Arduino board. So my question is, is it possible to connect two GPS modules placed at different locations from each other(but both connected to the same Arduino )?. I intend to use these GPS modules as waypoints, in that the coordinates are transmitted to an autonomous robot car to navigate to the coordinates.
It would be best if the Arduino board has more than one serial port. A Mega for instance. 1 GPS to Serial1 another to Serial2 and the Serial port would be left open for program upload, program debug and output.
so it is possible using multiple GPS on a single Arduino right?
alexmunala:
so it is possible using multiple GPS on a single Arduino right?
Yes
First, I made an assumption that you are using GPS with serial output. Is that correct? What GPS unit, exactly?
For serial output GPS units you need a serial port for each unit. A single Mega board has 3 "extra" hardware serial ports so easy to connect 3 GPS units to one Mega board.
I do not know, though, if the GPS library that you want to use can have several instances running at once.
I am using 2 NEO-6M GPS.
The purpose of the GPS module is to receive the coordinates of the points where they are located.in this case like two separate points. After getting these coordinates I have a Bluetooth module to be used to send the data(coordinates) to another Arduino autonomous robot to be used as waypoints during path planning of the robot.
They are serial output so what I have already posted applies.
How far from the Arduino are the 2 GPS units? You may need to take special precautions if the wires are long (more than a meter or two).
SoftwareSerial on an Uno would be fine two or three of those GPS. No need to use a Mega.
An Uno can use one instance of SoftwareSerial, but two or more instances becomes cumbersome.
groundFungus:
They are serial output so what I have already posted applies.How far from the Arduino are the 2 GPS units? You may need to take special precautions if the wires are long (more than a meter or two).
One of the GPS modules is located at zero distance from Arduino while the other one should be a meter or two meters from the Arduino. Then I would like them to be identified differently so that when the coordinates are being sent, it should be identified that its from which GPS and one to be sent before another, not both at the same time.
Then I would like them to be identified differently
You will connect each to its own serial port. That identifies which GPS that the data is coming from.
2 meters probably will not be a problem at 9600 baud (neo 6m default).
groundFungus:
You will connect each to its own serial port. That identifies which GPS that the data is coming from. 2 meters probably will not be a problem at 9600 baud (neo 6m default).
Thank you.
so, in this case, u advise using which board specifically?
Hi,
Welcome to the forum.
What sort of precision are you expecting from the GPS units?
Only a meter difference in location will be hard to detect as a STABLE distance reading.
May I suggest you have two Arduinos and two gps and move them around and see if you can obtain a reliable and stable distance measurement for POC, before trying for two GPS on one Arduino.
Can you tell us your electronics, programming, arduino, hardware experience?
Have you got a GPS already working with an Arduino?
Tom.. 
TomGeorge:
Hi,
Welcome to the forum.
What sort of precision are you expecting from the GPS units?
Only a meter difference in location will be hard to detect as a STABLE distance reading.May I suggest you have two Arduinos and two gps and move them around and see if you can obtain a reliable and stable distance measurement for POC, before trying for two GPS on one Arduino.
Can you tell us your electronics, programming, arduino, hardware experience?
Have you got a GPS already working with an Arduino?
Tom..
Hi,am not intending to get the distanc between the two GPS modules.what i need them to do is to get the coordinates of the points where i placed them,in this case O distance from Arduino and two metres from arduino.furtheremore i need them connected to one Arduino to recieve the same command.
so, in this case, u advise using which board specifically?
I would use a Mega because of the 4 hardware serial ports and because I am familiar with them. Any board that has multiple (3+) hardware serial ports would be easier to get working.
groundFungus:
I would use a Mega because of the 4 hardware serial ports and because I am familiar with them. Any board that has multiple (3+) hardware serial ports would be easier to get working.
okay.
alexmunala:
Hi,am not intending to get the distanc between the two GPS modules.what i need them to do is to get the coordinates of the points where i placed them,in this case O distance from Arduino and two metres from arduino.furtheremore i need them connected to one Arduino to recieve the same command.
So you want a car to travel between the two co-ordinates.
How precise do you need the readings, plus you will need a third GPS on the car.
Each GPS will have a error margin.
Have you at least connected a GPS to an Arduino and looked at the changing co-ords outputted by the "stationary" GPS and worked out how much a "stationary" GPS wanders/drifts in its readings?
Tom....
PS, I agree a mega would be ideal as you will need 2 uarts for the GPSs and another to communicate with the cars system.
groundFungus:
I would use a Mega because of the 4 hardware serial ports and because I am familiar with them. Any board that has multiple (3+) hardware serial ports would be easier to get working.
I forgot to mention,
Would I get different gps coordinates for the two separate module by a distance of 2meters apart?
Or, what would be the difference in precision of the two coordinates? Am asking this because I understand that there are cases where if you use the phones gps it would be the same if you moved 2-5 meters from the first point.
So, would there be a difference in the coordinates if I used the Arduino interfaced gps modules separated 2 or 3 meters apart?
TomGeorge:
So you want a car to travel between the two co-ordinates.
How precise do you need the readings, plus you will need a third GPS on the car.
Each GPS will have a error margin.
Have you at least connected a GPS to an Arduino and looked at the changing co-ords outputted by the "stationary" GPS and worked out how much a "stationary" GPS wanders/drifts in its readings?
Tom....
PS, I agree a mega would be ideal as you will need 2 uarts for the GPSs and another to communicate with the cars system.
Yes, I have 3 GPSs, one on the autonomous car with a digital compass and the two I've mentioned are on ground. The two as I mentioned on ground, are to be used as waypoints.
alexmunala:
I forgot to mention,
Would I get different gps coordinates for the two separate module by a distance of 2meters apart?
Or, what would be the difference in precision of the two coordinates? Am asking this because I understand that there are cases where if you use the phones gps it would be the same if you moved 2-5 meters from the first point.
So, would there be a difference in the coordinates if I used the Arduino interfaced gps modules separated 2 or 3 meters apart?
That is what I asked you?
Have you built a GPS/Arduino unit to check the drift/noise in the GPS outputted co-ordinates?
Tom...