The Measurement Technology Of Ship's Instantaneous Line Motion Under Multi Dynamic Environment

In recent years, with the further research on navigation technology, the functional expansion of inertial measurement techniques has become increasingly urgent demands. Ship's instantaneous line motion parameters that sway, surge and heave information extraction can not only meet the needs of ship maneuverability but also provide vehicle location, posture and movement status information.The traditional method thought waves to be a single frequency signal, and under the influence of that the instantaneous line movement information is also thought to be a single frequency signal. What's more, it didn't consider sport forms are different in different dynamic environment, which has some limitation the specific using.This paper, based on the strapdown inertial navigation system and the waves basic forms of exercise, gives the transient line motion model, and analyzes the speed of the ship working on the instantaneous line motion measurement parameters, then determines the measurement schemes when ship is mooring or navigating. Among them, the movement of ship navigation is more complex so that we use the Kalman filtering technique and the Doppler speed measurement equipment which can correct the instantaneous angular position information and get accurate speed.At the same time, the key technologies for digital filter designing are described in detail. It introduces the The basic principle and design method of finite impulse response filter (FIR) and infinite impulse response filter (ⅡR) and describes the band pass and high pass filter method according to different inertial measurement program when the ship mooring or navigating, and then gives power spectrum estimation method based on the random nature of the waves.According to the measurement program of ship's instantaneous line motion, computer simulation and multi-functional platform in the laboratory is designed to testify the method. The measurement method is provided by the simulation of wave model. The simulation results show measurement system of ship's instantaneous line motion is robust and has high accuracy.