T1 Ethernet between FMUK66 and NavQ
The RDDRONE-FMUK66 has a two wire 100BaseT1 Ethernet interface on board. The 8mmNavQ board does not include T1 Ethernet however an adapter may be used. To run the T1 Ethernet connection between FMUK66 and NavQ use a separate RDDRONE-T1ADAPT media converter.
The 8mpNavQ or "NavQPlus" will have two Ethernet interfaces. it is planned that one of these interfaces will natively be configured as 100BaseT1
It is not recommended to use DHCP in a vehicle such as a drone, since you generally don't want the network to change without knowing about the explicit details. Therefore since there is no DHCP and FMUK66 by default has a fixed IP of 10.0.0.2, we need to set a fixed IP on the NavQ for eth0 to be able to communicate via Ethernet to FMUK66.
It is suggested to use IP address 10.0.0.3 for navq.
The linux program connman is used for configuring the network settings . To force connman to use a fixed IP ( as in case when no DHCP is available) the following file needs to be created.
It is important is that you have a Ethernet cable connection before, otherwise connman will not register the network.
The IP4 settings are in the order of ownIP/netmask/router. Note that 10.0.0.3 is set as router since in this particular hardware configuration no other device is there.
T1 Ethernet is supported by PX4 on FMUK66 with latest master.
To enable the RDDRONE-FMUK66 mavlink telemetry via UDP sending to a specific IP you must add the following file on the FMUK66 SDcard:
/etc/extras.txt
In the example configuration above, 10.0.0.3 is the IP address of NavQ on the vehicle. More detailed description of the mavlink start parameters can be found here: https://dev.px4.io/v1.9.0/en/middleware/modules_communication.html
Additionally the MAV_BROADCAST parameter on the FMU needs to be set to "2 - only multicast".
Distributing MavLink data can be done by installing mavlink-router on NavQ.
mavlink-router routes MavLink data dynamically between several end nodes
To be able to have several end nodes communicating via mavlink simultaneously we need to set up mavlink-router on the NavQ. The end nodes can be
A process for onboard control running on NavQ.
A QGroundControl (QGC) computer the NavQ connects to via a data link such as WiFi.
Other mavlink enabled peripherals on the vehicle.
Another program running on the same remote PC as QGC
Connect to your FMU over USB and open QGroundControl. Navigate to Settings -> Parameters -> MAVLink and set these parameters:
Also, you'll need to make sure that the settings in Settings -> Parameters -> Serial look like this:
To install and compile mavlink router follow the steps below (internet access required on your NavQ)
1) Connect to NavQ console via ssh / serial
2) Type the following commands
Configuration of mavlink router is done via a single configuration file /etc/mavlink-router/main.conf
This file needs to be created from scratch. An example configuration file is available in the mavlink-router sources - https://github.com/intel/mavlink-router/blob/master/examples/config.sample
As of today the mavlink-router make install does not create the /etc/mavlink-router directory and main.conf file. Therefore please use the following commands to create the directory and file initially.
~$ sudo mkdir /etc/mavlink-router
~$ sudo touch /etc/mavlink-router/main.conf
The configuration above assumes that the NavQ gets mavlink data from FMU either via UART3 (/dev/ttymxc2) or UDP. If you use UART please set on the FMU the corresponding serial port to 921600Bd. For this the SER_TELx_BAUD (x = number of telemetry port) parameter needs to be adjusted to 921600 8N. If you use lower speed QGroundControl might fail to load parameters.
You can leave out the unused connection.
Via the UdpEndpoint QGConMobile section the mavlink stream is forwarded to a QGC computer/mobile device assuming it has 192.168.43.1 and NavQ is connected to this network via e.g. WiFi.
Enable the auto-start of mavlink-router via systemd and start it
You can check the status of mavlink router using the command
