Freefly RTK GPS
Last updated
Last updated
The Freefly Systems RTK GPS Module is a multiband RTK GPS module from Freefly Systems that provides highly reliable navigation. The modules can act as either rovers (when installed on an aircraft) or base stations (when plugged into a computer).
Main features include:
Multiband (L1/L2) receiver (u-blox ZED-F9P)
Concurrent reception of all 4 GNSS (GPS, Galileo, GLONASS, BeiDou)
Built-in magnetometer (IST8310), baro (BMP388), RGB LED, safety switch and safety LED
:::note This module can be used with PX4 v1.9 or above (support for the u-blox ZED-F9P was added in PX4 v1.9). :::
An RTK GPS kit includes:
2x GPS modules with antennas
3m USB C to A cable
Magnetic quick-mount for base station module (1/4-20 thread for tripod mounting)
Screws to mount onto a Freefly AltaX
RTK setup and use on PX4 via QGroundControl is largely plug and play (see RTK GPS for more information).
For the aircraft, you should set the parameter SER_GPS1_BAUD to 115200 8N1 to ensure that PX4 configures the correct baudrate.
The Freefly RTK GPS comes with an 8 pin JST-GH connector that can be plugged into a PixHawk autopilot. For use as a base station, the module has a USB-C connector
The Freefly GPS pinout is provided below. For some autopilots, like the Hex Cube and PixRacer, all that is needed is a 1-1 8-pin JST-GH cable.
| Pin | Freefly GPS |
|---|---|
1 | VCC_5V |
2 | GPS_RX |
3 | GPS_TX |
4 | I2C_SCL |
5 | I2C_SDA |
6 | BUTTON |
7 | BUTTON_LED |
8 | GND |
u-blox ZED-F9P GPS Receiver
Ultracap backup power for fast (hot-start) restarts
EMI shield over receiver for improved EMI immunity
IST8310 Magnetometer
Safety-switch and safety LED
RGB LEDs for status indication
NCP5623CMUTBG I2C Driver
BMP388 Baro on I2C bus
External, active antenna (Maxtena M7HCT)
SMA connector
STM32 MCU for future CAN-based communication
FW updates through USB connector
Connectivity:
USB-C
2-way USB Switch to MCU and F9P
SMA for active antenna (20mA max)
4-pin JST-GH CAN Bus (dronecode compliant)
8-pin JST-GH UART/I2C -** Power:
Input from either (diode OR'd):
USB (5V)
CAN (4.7 to 25.2V)
(4.7 to 25.2V)
Power consumption <1W
More information can be found on Freefly's Wiki
