Quantum Magnetometer Navigation: Magnetic Anomaly Particle Filter

A robot with no GPS signal drives across a terrain whose magnetic field is warped by buried anomalies, sensed by a quantum magnetometer. A live particle filter of pose hypotheses is propagated with noisy odometry and re-weighted against the anomaly map every step, so you can watch the cloud disperse in featureless field regions and snap tight whenever the robot crosses a strong magnetic gradient — the real mechanism behind GPS-denied magnetic-anomaly navigation, distinct from inertial dead-reckoning because the correction comes from matching an external map rather than integrating acceleration.