Docs: Change Hostname

Mon, 01 Jan 0001 00:00:00 +0000

Changing the hostname is simple, thanks to the raspi-config tool:

Run sudo raspi-config
Select System Options -> Hostname
Enter a new hostname and press Enter`
Finish and Reboot

Docs: Creating a Debug Recording

Mon, 01 Jan 0001 00:00:00 +0000

When investigating issues — especially positioning problems — a rosbag recording gives developers a full snapshot of sensor data to analyse. This guide walks you through recording one and retrieving it from your mower.

Privacy notice

A rosbag records raw sensor data, which includes the GPS position of your mower. By sharing the file you disclose the physical location of your garden. Only share it with people you trust.

Prerequisites

OpenMower is running and the mower has a GPS fix (green GPS icon in the app)
You can access the mower via SSH or the web terminal

Step 1: Start the recording

Connect to your mower via SSH or the web terminal, then enter the ROS shell:

openmower shell

Once inside, navigate to the recordings directory and start recording all topics:

cd /data/recordings
rosbag record -a

This records all active ROS topics. Leave the terminal open — the recording runs until you stop it with Ctrl+C.

Step 2: Enter area recording mode

Open the OpenMower app and activate area recording mode — the same mode you use when recording mowing areas. This ensures all relevant topics (GPS, IMU, wheel odometry) are actively publishing at full rate.

GPS fix required

Make sure the GPS icon in the app is green before driving. Recording without a fix produces data that cannot be used for analysis.

Step 3: Drive the test patterns

Drive the mower through the following patterns. Each one exercises a different aspect of positioning:

Pattern	Purpose
Straight lines	Linear odometry and GPS consistency
Figure-8	Combined turning and straight-line tracking
Rotate on the spot (clockwise)	Yaw estimation, IMU vs. GPS heading
Rotate on the spot (counter-clockwise)	Same, opposite direction

A minute or two of each pattern is sufficient. You don’t need a large area — a small open patch of lawn works fine.

Step 4: Stop the recording

Once done, go back to the terminal and press Ctrl+C, then type exit to leave the ROS shell.

The .bag file is now in ~/recordings/ on the mower. List the directory to find your filename:

ls -lh ~/recordings/

The filename includes a timestamp, e.g. 2024-06-01-12-34-56.bag.

Step 5: Retrieve the file

Copy the .bag file from ~/recordings/ on the mower to your computer.

Linux / macOS
Windows

Use scp from your local terminal:

scp openmower@<mower-ip>:recordings/<filename>.bag .

Replace <mower-ip> with your mower’s IP address and <filename> with the actual filename. The file downloads to your current directory.

Windows 10 (build 1809 or later) and Windows 11 include an OpenSSH client. Open Command Prompt or PowerShell and run:

scp openmower@<mower-ip>:recordings/<filename>.bag .

On older Windows versions, use a graphical SFTP client instead:

WinSCP — free, open source
Cyberduck — free, cross-platform

Connect with protocol SFTP, host <mower-ip>, user openmower, and navigate to /home/openmower/recordings/ to download the file.

Tip

.bag files compress very well. Zipping before sharing can reduce the file size significantly:

Once you have the file, share it with whoever is helping you debug — via Discord, a file sharing service, or any other method that works in context.

Step 6: Clean up

Once debugging is done, delete the recordings from the mower to free up disk space:

# delete a specific file
rm ~/recordings/<filename>.bag

# delete all recordings
rm ~/recordings/*.bag

OpenMower — Open Source RTK GPS Robotic Mower – Maintenance