engineering

Navigation & Positioning Systems

The science of determining position and trajectory — GPS satellite trilateration, inertial navigation with gyroscopes and accelerometers, Kalman filter sensor fusion, map-matching algorithms, and dead-reckoning propagation.

GPSnavigationinertial navigationKalman filtermap matchingdead reckoningpositioningGNSS

Navigation systems determine position, velocity, and orientation using a combination of satellite signals, inertial sensors, and computational algorithms. From smartphone mapping to autonomous vehicles and spacecraft guidance, modern navigation relies on the fusion of multiple imperfect measurements into a single best estimate of state.

These simulations let you trilaterate GPS positions from satellite pseudoranges, propagate inertial navigation states with accelerometers and gyroscopes, run Kalman filters that optimally fuse noisy sensors, snap trajectories to road networks with map-matching, and propagate dead-reckoning estimates from heading and speed — all with real-time interactive controls and physically accurate models.

5 interactive simulations

simulator

Dead Reckoning & Position Propagation

Simulate dead reckoning — explore how speed error, heading error, drift time, and update interval cause position uncertainty to grow from a known starting point

simulator

GPS Trilateration & Satellite Positioning

Simulate GPS positioning — explore how satellite geometry, clock bias, atmospheric delay, and signal noise affect position accuracy through trilateration

simulator

Inertial Navigation System (INS)

Simulate inertial navigation — explore how accelerometer bias, gyroscope drift, integration time, and initial alignment affect position and attitude errors

simulator

Kalman Filter & Sensor Fusion

Simulate a Kalman filter — explore how process noise, measurement noise, initial uncertainty, and update rate affect optimal state estimation and sensor fusion

simulator

Map Matching & Road Snapping

Simulate map matching — explore how GPS noise, road network density, heading constraint, and candidate search radius affect snapping GPS traces to road segments