earthrovers_base

earthrovers_base

This package mainly houses the base node, which is one of the core nodes used to interface with the Earth Rovers SDK.

base node

ROS Topics Subscribed

ROS Topic	Interface	Description
cmd_vel	geometry_msgs/Twist	Linear and Angular velocity command to send to the FrodoBot.

ROS Topics Published

ROS Topic	Interface	Description
imu	sensor_messages/Imu	Most recent angular velocity and linear acceleration returned by the Earth Rovers SDK /data endpoint.
magnetic_field	sensor_messages/MagneticField	Most recent magnetic field measurement returned by the Earth Rovers SDK /data endpoint.
gps	sensor_messages/NavSatFix	The newest GPS latitude and longitude available from the SDK /data endpoint.
orientation	std_msgs/Float32	Orientation computed by the SDK from the magnetometer data returned from the /data endpoint.
battery	sensor_msgs/BatteryState	Battery message with only the percentage is populated from the battery level provided by the /data endpoint.

Notes/Disclaimers

• Eventually, the orientation field may not need be used, as the magnetic field data could be used directly by something like imu_filter_madgwick from imu_tools to produce orientation estimates.
• GPS messages are currently ONLY PUBLISHED when a change in the reported latitude/longitude is detected. This is done so that multiple, identical GPS fixes are not sent out as if they were two separate fixes / locations.