Holybro DroneCAN M8N GPS

The Holybro DroneCAN GPS has an UBLOX M8N module, BMM150 compass, tri-colored LED indicator.

The GPS module uses the DroneCAN protocol for communication. DroneCAN connections are more resistant to electromagnetic interference compared to serial connection, making it more reliable. In addition, using DroneCAN means that the GPS and compass do not occupy any flight controller serial ports (different/additional CAN devices can be connected to the same CAN bus via a CAN splitter board).

Where to Buy

Order this module from:

• Holybro

Hardware Specifications

	DroneCAN M8N
GNSS Receiver	Ublox NEO M8N
Number of Concurrent GNSS	2 (Default GPS + GLONASS)
Processor	STM32G4 (170MHz, 512K FLASH)
Compass	BMM150
Frequency Band	GPS: L1C/A GLONASS: L10F Beidou: B1I Galileo: E1B/C
GNSS Augmentation System	SBAS: WAAS, EGNOS, MSAS, QZSS
Navigation Update	5Hz Default(10Hz MAX)
Navigation sensitivity	–167 dBm
Cold starts	~ 26s
Accuracy	2.5m
Speed Accuracy	0.05 m/s
Max # of Satellites	22+
Default CAN BUS data rate	1MHz
Communication Protocol	DroneCAN @ 1 Mbit/s
Supports Autopilot FW	PX4, Ardupilot
Port Type	GHR-04V-S
Antenna	25 x 25 x 4 mm ceramic patch antenna
Voltage	4.7-5.2V
Power consumption	Less than 200mA @ 5V
Temperature	-40~80C
Size	Diameter: 54mm Thickness: 14.5mm
Weight	36g
Cable Length	26cm
Other	LNA MAX2659ELT+ RF Amplifier Rechargeable Farah capacitance Low noise 3.3V regulator 26cm cable included

Hardware Setup

Mounting

The recommended mounting orientation is with the arrow on the GPS pointing towards the front of vehicle.

The sensor can be mounted anywhere on the frame, but you will need to specify its position, relative to vehicle centre of gravity, during PX4 configuration.

Wiring

The Holybro DroneCAN GPS is connected to the CAN bus using a Pixhawk standard 4 pin JST GH cable. For more information, refer to the CAN Wiring instructions.

Pinout

Diagram showing GPS pinouts

Dimensions

Diagram showing GPS dimensions

PX4 Configuration

You need to set necessary DroneCAN parameters and define offsets if the sensor is not centred within the vehicle. The required settings are outlined below.

:::note The GPS will not boot if there is no SD card in the flight controller when powered on. :::

Enable DroneCAN

In order to use the ARK GPS board, connect it to the Pixhawk CAN bus and enable the DroneCAN driver by setting parameter UAVCAN_ENABLE to 2 for dynamic node allocation (or 3 if using DroneCAN ESCs).

The steps are:

• In QGroundControl set the parameter UAVCAN_ENABLE to 2 or 3 and reboot (see Finding/Updating Parameters).

• Connect GPS CAN to the Pixhawk CAN.

Once enabled, the module will be detected on boot. GPS data should arrive at 5Hz.

DroneCAN configuration in PX4 is explained in more detail in DroneCAN > Enabling DroneCAN.

Sensor Position Configuration

If the sensor is not centred within the vehicle you will also need to define sensor offsets:

• Enable GPS yaw fusion by setting bit 3 of EKF2_GPS_CTRL to true.

• Enable UAVCAN_SUB_GPS, UAVCAN_SUB_MAG, and UAVCAN_SUB_BARO.

• Set CANNODE_TERM to 1 if this is that last node on the CAN bus.

• The parameters EKF2_GPS_POS_X, EKF2_GPS_POS_Y and EKF2_GPS_POS_Z can be set to account for the offset of the ARK GPS from the vehicles centre of gravity.