Common Software Tasks

The various subheadings of this document are linked in other pages. This page is meant as a reference for commonly performed tasks.

Password-Free Access

For password free access to the Orin, follow these steps:

  1. Ensure that you have an SSH key in ~/.ssh
    1. If not, run ssh-keygen -t ed25519 -C <yourCommentHere>
  2. With the USB connected, run ssh-copy-id lis@192.168.55.1
  3. Make sure that the ssh-agent is on: eval `ssh-agent`
  4. Add your key to the agent: ssh-add
  5. Ensure that you can access the device without a password: ssh lis@192.168.55.1

Wi-Fi Setup

SSH into the Orin. The following is a reference for commands that you can use with nmcli:

To see available Wi-Fi networks: nmcli device wifi list

To connect to a network with simple auth (open or WPA2/WPA3 password): sudo nmtui -> Activate Connection, or: 

sudo nmcli connection add type wifi \ 
con-name "NetworkName" \
ssid "SSID" \
wifi-sec.psk "password" \
wifi-sec.key-mgmt "wpa-psk"

To connect to a more complicated network (eduroam/epfl): 

sudo nmcli connection add type wifi \
con-name "epfl" \
ssid "epfl" \
wifi-sec.key-mgmt wpa-eap \
802-1x.eap ttls \
802-1x.phase2-auth mschapv2 \
802-1x.identity "YourUsername" \
802-1x.password "YourPassword" \
802-11-wireless.bssid "AA:BB:CC:DD:EE:FF"

Replace YourUsername, YourPassword with your GASPAR credentials. You can find the bssid of your local router by nmcli device wifi list. Use that instead of AA:BB:CC:DD:EE:FF.

To activate a connection, you can either use sudo nmtui, or:

`nmcli con up

Wireless Connection to QGroundControl

This is done with mavros. This should be done with the preflight Ansible. You can inspect the script in ansible/scripts/mavros_start.sh and the lines related to Mavros in ansible/drones_preflight.yml.

Get IP of Computer

You can get the internet protocol address of a Linux computer by running ifconfig and looking for the four numbers after inet under the interface that you care about. Wireless interfaces typically begin with w, and ethernet interfaces typically begin with e.

On most networks, you can usually use hostname.local in place of the IP address if the two computers are on the same network. Replace hostname with the hostname of the computer. You can get the hostname by running: hostname or hostnamectl on the computer.

Rescue Unreachable Device

If you do not know the IP address of a drone, you can try these steps to find it's IP:

  1. Try restarting everything first.
  2. Try running avahi-resolve -n hostname.local while on the same network.
  3. Try running avahi-resolve -n hostname-2.local. Sometimes, the original hostname gets reserved and this becomes a fallback. If this works, you can run avahi-publish in the background with the original hostname to force it to work.
  4. Connect to the recovery port using a USB-C cable. You should be able to SSH into the device at 192.168.55.1 and use ifconfig to find the IP.
    1. Then, you can use avahi-resolve -a <ip> to find the mDNS hostname.

VNC/Remote Desktop Setup

On the host computer, go to terminal and type gvncviewer lis@nxt1.local where nxt1 is the hostname of the Orin on which is on the same network as the host computer. Then input the password 'orin'. This will allow you do remote desktop into the Orin. You can also replace nxt1.local with the full IP address of the orin e.g. gvncviewer lis@192.168.55.1.

Important

If you want to connect the Orin to an external monitor, you have to first modify /etc/X11/xorg.conf and comment all the the paragraph that starts with Section "Device" and contains Identifier "Dummy0", as well as all the lines after it.

Check EKF Tracking

To check EKF tracking, perform the following steps:

  1. On the host computer, make sure ros is sourced: source /opt/ros/humble/setup.bash
  2. Ensure the ROS_DOMAIN_ID is set to the same value as the drones. By default, this is 1. You can check in ansible/group_vars/all: export ROS_DOMAIN_ID=<domain id>
  3. Run plotjuggler: ros2 run plotjuggler plotjuggler
  4. In plotjuggler, add:
    1. /mavros/local_position/pose xyz, orientation quaternions (EKF Output)
    2. /mavros/vision_pose/pose_cov xyz, orientation quaternions (optitrack)
  5. Move the drone around in all directions and ensure there are no discontinuities, and the values are tracking each other.
  6. Rotate the drone in different directions and ensure the values are tracking each other