C-RTK3 G5 User Guide

This chapter applies to the scenario of using the C-RTK3 G5 with ArduPilot vehicles.

[!NOTE] ArduPilot 4.4.0 and later versions support the C-RTK3 G5.

Flight Controller Parameter Configuration (CAN Connection, Recommended)

• Take out the CAN cable from the accessory package, connect the flight controller to the CAN port of the C-RTK3 G5; install the antennas for the C-RTK3 G5, and keep the distance between the two antennas more than 20 cm.
• Connect the flight controller to the ground station (such as Mission Planner / LGC) via USB.
• Enter the Full Parameter List, input parameter names in the search bar and set the following parameters. // Mission Planner path: Configuration/Tuning → Full Parameter List → Search bar on the right

[!NOTE] If you are unclear about the relative installation position, refer to the antenna offset diagram in the following part; Antenna 1 (ANT1) is the master antenna, Antenna 2 is the slave antenna.

For firmware versions below ArduPilot 4.6 (exclusive):

Master-Slave Antenna Offset Diagram

Heading Verification

• GPS heading data is displayed as gpsyaw in the status bar of Mission Planner flight data toolbar.
• Check whether the gpsyaw value is consistent with the actual heading.
• Rotate the airframe and verify if the gpsyaw value responds correctly to rotation.

[!NOTE] If you cannot confirm the actual direction, you may use the built-in compass of a mobile phone for reference. Keep away from batteries to avoid magnetic interference.

Troubleshooting

1. If the gpsyaw value remains always 0, the flight controller fails to obtain heading data. Possible causes:
2. Incorrect master-slave antenna offset settings; setting error shall not exceed 20%.
3. Poor satellite positioning quality; place the module outdoors with open sky view.
4. Poor or no positioning of the slave antenna; check antenna and feeder connection.

5. The module is working in single-antenna mode; check related parameters.

6. The vehicle spins 360° and cannot hold position in GPS mode:

7. First exclude compass faults, then check the following items:
8. Excessive error or incomplete configuration of GPS position offset parameters (GPS_POS1_X/Y/Z).
9. Poor GNSS positioning quality.
10. Disable SBAS augmentation. In areas with weak or no SBAS coverage, enabling SBAS may cause position drift.

UART Connection Parameter Configuration

[!NOTE] ArduPilot 4.4.0 and later versions support the C-RTK3 G5.

Interference Status Display

[!NOTE] The C-RTK3 G5 supports interference status display, which requires compatible flight controller firmware and ground station support. Please contact CUAV technical support if needed.