On measured-error pretreatment of bionic polarization navigation

A signal pre-treatment algorithm based on combination of 3-dimension system identification and Kalman filtering estimation（3DSKE）is proposed.The aim of designing the 3DSKE algorithm is to reduce errors caused by random noise,but leave the systematical errors caused by signal source remained to be solved by a special method.The 3DSKE algorithm is especially suitable for time series of pure measured data without dynamic equation and on-line real-time execution.The simulated result shows that the 3DSKE algorithm can help the basic theoretic calculation to realize feasible,stable,fast,high accurate and auto-executing computing process for the navigation applications.

Review on bio-inspired polarized skylight navigation

In this review, the research progress of bio-inspired polarized skylight navigation is evaluated from the perspectives of theoretical basis, information detection, sensor design, and navigation realization. First, the theory for characterizing the polarization mode of the skylight was introduced. Second, using sunlight, moonlight, and ocean as backgrounds, the measurement results of skylight polarization distribution under different weather conditions are described to compare the variation patterns. Third, the development history and research outcomes of bionic polarization navigation sensor for polarized skylight detection and navigation information calculation are categorized into two types, namely non-imaging and imaging types. In precision measurement, the non-imaging type is higher than the imaging type, and the accuracy that it can reach is ± 0.1° of navigation accuracy without drift error. Fourth, two polarized skylight orientation algorithms,E-vector-based method and Solar Meridian-Anti Solar Meridian(SM-ASM)-based method are summarized. Fifth, this review details the combined application of polarized skylight navigation sensors and Inertial Navigation System(INS), Global Navigation Satellite System(GNSS), Vision,Simultaneous Localization and Mapping(SLAM), and other navigation systems. The yaw and trajectory accuracy can be increased by about 40% compared to classical navigation system in complex outdoor environments. Finally, the future development trends of polarization navigation are presented.

Reviews and Expectations on the Maiden Voyage of a Chinese Merchant Ship in the Arctic Northeast Route

This paper introduces the preparatory work and conducts an integrated review on the maiden voyage of a Chinese commercial ship on the Arctic Northeast Route. It puts forth expectations on the exploitation and utilization of the Arctic Northeast Route in the aspects of safety, fastness, low costs, low consumption of energy and less pollution, knowledge of maritime law and navigation practice, building seaworthiness ships and making studies on the methods of sailing and maneuvering for navigation in polar waters, training qualified seafarers with navigation experiences in ice waters and establishing a safeguard system for the navigation in this route through the analysis on the weather, temperature, ice condition, route and hydrology encountered in the practice of a Chinese merchant ship in its maiden voyage in the route, and studies on the ice pilotage, convoy by icebreaker, practical condition of communication and navigation equipment in sea areas of high latitude and the economic benefit of the navigation in the Arctic Northeast Route.

Bioinspired Polarized Skylight Orientation Determination Artificial Neural Network

This paper proposes an artificial neural network to determine orientation using polarized skylight. This neural network has specific dilated convolution, which can extract light intensity information of different polarization directions. Then, the degree of polarization (DOP) and angle of polarization (AOP) are directly extracted in the network. In addition, the exponential function encoding of orientation is designed as the network output, which can better reflect the insect’s encoding of polarization information and improve the accuracy of orientation determination. Finally, training and testing were conducted on a public polarized skylight navigation dataset, and the experimental results proved the stability and effectiveness of the network.