Quaternion ↔ Euler Converter

Orientation is where many ROS bugs hide. A sensor mounted upside down, a camera frame pointing the wrong way, a quaternion copied with its components in the wrong order: all of these produce robots that are confidently wrong. The Quaternion ↔ Euler Converter makes orientations easy to check.

What it does

• Converts roll, pitch and yaw (degrees or radians) to a quaternion and back, using the ROS conventions from REP 103.
• Draws the rotated axes over the original frame in a 3D view you can orbit.
• Shows the rotation matrix, the axis and angle, and the equivalent negated quaternion.
• Warns about unnormalised quaternions and gimbal lock.
• Writes ready-to-paste static_transform_publisher commands, a URDF joint, a message snippet, and Python and C++ code.

How it is checked

We compare the converter with SciPy's rotation module and ROS's own tf_transformations package on thousands of random orientations, including the gimbal-lock cases. The results agree to about 10⁻¹³ radians.

Open the Quaternion ↔ Euler Converter. The guides below explain quaternions, the ROS axis conventions, gimbal lock, conversion code in Python and C++, and static transforms for sensors.