Access the RTK installed with the onboard computer

In cases where customers sometimes install RTK GPS directly with the onboard computer, we also support sending the corresponding RTK signals from the ROS side to the autopilot for high-precision positioning.

QF RTK case

Taking the QF RTK as an example, we refer to its ROS source code: https://gitee.com/qonfon/qfrtk_t3 . After starting the ROS driver, it will publish three location-related topics, with message types: gpgga, navOdometry, and navSatFix. When starting, we need to modify the enu_pose parameter in its default launch file to output ENU coordinates:

<param name = "enu_use" value = "1"/>  //1: ENU frame; 2: NED frame; 0: ECEF frame

We need to remap its three corresponding topics to the following mavros topics:

/mavros/gpsstatus/rtk/gpgga_output
/mavros/gpsstatus/rtk/navsatfix_output
/mavros/gpsstatus/rtk/odom_output

On the autopilot side, we set the GPS_RTK_ONB_EN parameter to 1, and then we can start the mavros node in the docker container following the normal operating procedure.