All algorithms used in Greensea's INS are in the openSEA library. The INS completes statistical filtering of sensor data via several discrete filtering algorithms before including the data in the state estimate. Additionally, the INS uses a variation of a discrete Kalman filter. The openSEA discrete Kalman is abstract and dynamic for scalability, and includes the kinematics for state estimation based on an acceleration and gyroscopic process aided by other observing measurements for velocity, position, or rotation.
The following diagram shows a generic discrete Kalman method. (Brown, Robert Grover and Hwang, Partrick Y.C., "Introduction to Random Signals and Applied Kalman Filtering, Third Edition, John Wiley and Sons, 1997).
Illustration 1: Generalized discrete Kalman algorithm.
