Novel approach to GPS/SINS integration for IMU alignment

摘要: Strapdown inertial navigation system (SINS) requires an initialization process that establishes the relationship between body frame and local geographic reference. This process, called alignment, is generally used to estimate initial attitude angles. possible because accurate determination of measurement unit (IMU) motion available based on obtained from global position (GPS). But update frequency GPS much lower than SINS. Due non-synchronous data streams SINS, angles may not be computed accurately enough. In addition, estimated have relatively large uncertainties can affect accuracy other parameters. paper presents effective approach matching velocities which are provided by this approach, a digital high-pass filter, implements pre-filtering scheme measured signal, filter Schuler cycle discrete velocity difference SINS GPS. Simulation results show improves greatly makes convergence time satisfy required accuracy.