Quaternion Rotations

Quaternion Rotations

Quaternions provide a singularity-free way to represent 3D rotations. Every unit quaternion q = w + xi + yj + zk encodes a rotation by angle 2·arccos(w) around the axis (x, y, z).

Animate

Current Quaternion

q = 0.924 + 0.000i + 0.383j + 0.000k

|q|² = w² + x² + y² + z² = 1

Key Properties

  • • Unit quaternions ≅ SU(2) ≅ S³
  • • Double cover of SO(3): q and −q encode the same rotation
  • • No gimbal lock (unlike Euler angles)
  • • Smooth interpolation via SLERP