Design and Real-Time Implementation of a 3-Stage CnW Heading System on an Ubuntu Linux-Embedded Board

This paper describes the design and real-time implementation of a proposed algorithm for deriving an accurate heading system by fusing data from various inexpensive sensor devices that is comparable to more expensive maritime navigation systems. The proposed algorithm is a 3-Stage Classification N’ Weighing (CnW) Heading System with forward azimuth (FAz) and extended Kalman filter (EKF). Data from three Global Positioning System devices, an inertial measurement unit, and an electronic compass were fed into the algorithm that can be generally described as Classification N’ Weighing-Stage 1 → forward azimuth → Classification N’ Weighing-Stage 2 → extended Kalman filter → Classification N’ Weighing-Stage 3. The proposed algorithm is shown to be comparably accurate as an expensive marine navigation system, and it has less processing time compared to our previous work. The Qt-anywhere-based system developed on a Linux desktop was successfully downloaded onto an Ubuntu Linux-embedded board for real-time implementation. Important notes related to device naming problems when deploying the system on a Linux-embedded board are also given as reference for those interested to address it.

Nonlinear Modeling and Virtual Scene Simulation of the Z-Propeller Tug

Ship maneuvering model and ocean scene are the core parts of navigation simulator, on the basis of MMGs model, the dual-engine and dual-propelling equipment of the Z-propeller tug were researched, the tugs mechanical model and propulsion model were established, speed, course and path of the tug were calculated with the Runge-Kutta method; virtual ocean was built at the meantime based on waves statistic spectrum and fast fourier transform; at last, data communication between different softwares was realized by means of UDP and ADO protocol, and virtual marine navigation system was established based on the Z-propeller tugs maneuvering model.