Jetson Nano to Pixhawk

The connection using Mavlink and for these methods I've tried Dronekit and ROS. This documentation consists both of them.

• Ubuntu 20.04
• Jetpack 4.6
• MicroSD 128 GB Sandisk A2

ROS Noetic MAVROS

First things first install ROS Noetic based on these articles on ros wiki It is recommended to install ROS-Dekstop or ROS-Base only, the full version of ROS will take a lot of storages.

sudo apt install ros-noetic-desktop

or run

sudo apt install ros-noetic-ros-base

then install the mavros package from Ardupilot article

sudo apt-get install ros-noetic-mavros ros-noetic-mavros-extras

here we will need a Geographiclib, don't download it, just run from the mavros folder

cd /opt/ros/noetic/lib/mavros/
sudo ./install_geographiclib_datasets.sh

it will take about 10 minutes or more, just wait for it. setup the ros installation

source /opt/ros/noetic/setup.bash
echo "source /opt/ros/noetic/setup.bash" >> ~/.bashrc
source ~/.bashrc

connect the pixhawk to jetson using micro USB, the connection will establish as /dev/ttyACM0, you can verify using ls /dev/tty* before connect to the pixhawk, we have to set permission for the /dev/ttyACM0 using user dialout, replace the <username> with your own username

sudo chmod +x /dev/ttyACM0
sudo usermod -a -G dialout <username>

then we can access the pixhawk with mavros, for standard pixhawk 2.4 using apm.launch and pixhawk cube with apm2.launch

roslaunch mavros apm.launch

open new terminal to monitor the ros node

rostopic list
rostopic echo <the node that you want to monitor e.g./mavros/state>

to test arming the motor, please set the precheck arm in Mission Planner, and complete the pre-arming check then we can try to arm the motor

rosrun mavros mavsafety arm

Dronekit

Dronekit is a python library to interact with MAVLink, let's get it

sudo apt-get update
sudo apt-get upgrade
sudo apt-get install python-dev
sudo pip install future
sudo apt-get install screen python-lxml
sudo pip install pyserial dronekit MAVProxy

connect the pixhawk using USB

sudo mavproxy.py --master /dev/ttyACM0

then will come up this message if completed

Connect /dev/ttyACM0 source_system=255
Log Directory:
Telemetry log: mav.tlog
Waiting for heartbeat from /dev/ttyACM0
MAV> Detected vehicle 1:1 on link 0
online system 1
STABILIZE> Mode STABILIZE
AP: PreArm: RC not found
AP: PreArm: Hardware safety switch
fence present
Servo volt 1.0
AP: ArduCopter V4.4.0 (502702df)
AP: ChibiOS: 1ec9f168
AP: Pixhawk1 002E002F 32385109 34343039
AP: RCOut: PWM:1-14
AP: IMU0: fast sampling enabled 8.0kHz/1.0kHz
AP: Frame: QUAD/X

By: Oki Aryawan