Here you'll learn how to add an of-the-shelf GPS module to the Rover functionalties.
The first step is to choose an appropriate GPS module. Before you make a decision, make sure your GPS sensor can communicate via a serial interface and can sending data in NMEA format. In the tutorial, we apply the u-blox neo-6m GPS module. Link to the datasheet.
U-blox NEO-6m GPS module
UART GPS NEO-6M UART GPS Module, NEO-6M onboard, curved/horizontal pinheader
UART GPS Module, NEO-6M onboard, curved/horizontal pinheader
To connect the GPS module to the Core2ROS driver, use the hSense port 3.
Connect the GPS module according to pin description below. The easiest way to connect GPS module to the controller is to use IDC connector and four jumper cables.
Mounting GPS module on the top of the Rover
The best way to get clear GPS data from the module is to mount it as far from the Rover's electronics as possible. We recommend mounting it on the top of the Rover so the module is shielded from its bottom and has clear 'view' to the satellites.
First you need to route the module cables out of the main electronics box (MEB). The easiest way is to use one of Dev-Covers that we prepared for such projects.
Dev-Covers for addons
We didn't prepare any 3D-model of the module support yet. You'll need to be more creative sourcing or desiging your own.
Enable GPS functionality
Make sure your rover is up-to-date. GPS functionality was added to the default firmware in the v1.0.0 release.
Open a new remote terminal session on the Rover:.
Connect via SSH
Enable the GPS functionality by calling the service to /core2/set_gps
rosservice call /core2/set_gps true
Restart the board to apply changes.
You can restart the board by calling the service core2/reset_board
rosservice call /core2/reset_board
Check if it works
Check if the GPS module is configured properly by listing available topics. You should see the new topic /gps_fix .
To check if GPS is publishing data correctly, type:
rostopic echo /gps_fix
There will be coordinate data occurring only if GPS found its position.
Check if the coordinates obtained are correct in Google Maps.