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The risk assessment is an important means to obtain the status of system security and an important basis to develop security solutions as well. Taking the integrated navigation system as the research object, this article proposes an evaluation model which can apply to the system of risk assessment taken by the neural network and the fuzzy theory. The model use the fuzzy evaluation method to quantize...
The risk assessment is an important means to obtain the status of system security and an important basis to develop security solutions as well. For there are a lot of uncertainty in the index value of the risk factors, using the improved fuzzy AHP system model to carry out analysis and evaluation combined qualitative and quantitative, achieving the index quantified for system security risk factors,...
Due to geomagnetic anomaly strength can't be separated from magnetic field data, underwater vehicle localization based on geomagnetic anomaly needs vehicle draft depth information. For this localization method, we conclude that the simplest configuration be seven single-axis vector magnetometers to measure magnetic dipole gradients. The essential conditions and optimal measurement matrix of magnetic...
For the strapdown inertial navigation system, whether the output signal of 3-axes fiber optic gyroscopes (FOG) is synchronized or not, impacts the performance of system seriously. This paper gave a novel way to make the gyros' signal synchronized without any change of hardware. Firstly, the all-digital closed-loop signal processing of single FOG was analyzed deeply, especially the part of digital...
The risk assessment is an important means to obtain the status of system security and an important basis to develop security solutions as well. Taking the integrated navigation system as the research object, this article establishes the risk assessment index system based on the analysis of the composition and the characteristic foundation of the integrated navigation system, carrying on the assessment...
Because dipole magnetic anomaly caused by ferromagnetic object or geologic structural change is mixed with geomagnetic field and difficult to calculate its magnitude, it lead to a problem for automatic underwater vehicle (AUV) localization aided by geomagnetic anomaly. To solve this issue, a novel AUV localization method introducing draft depth is put forward, where vertical position of AUV relative...
The relative position between magnetic target and the device, which is installed on vehicle under water, is determined by measuring magnetic field magnitude and its gradient of target on condition that geomagnetic field anomaly can be viewed as a magnetic dipole object. The errors of measuring magnetic field and its gradient caused by nonorthogonality between axes, different sensitivity of each axis,...
Vehicle mobile movement can cause dynamic error of the platform inertial navigation system (PINS) which is widely used in underwater vehicle. Taking PINS as the research object, the space motion mathematical models of underwater vehicle are analyzed and established by reasonable simply. Through coordinate transformation relationship research of the fixed coordinate system, the moving coordinate system...
Accuracy of marine inertial navigation system (INS) is mainly dominated by gyroscope. In this paper, a new scheme (inertial gyrocompass system) is designed to realize high accuracy INS on the basis of low accuracy float gyros and velocity information of Doppler log. By choosing optimal 2-order horizontal damping network and 1-order azimuth damping network and designing logical damping parameter, the...
Shell-feeding velocity is an important factor affecting naval gun shooting capacity. An agile shell-feeding system was designed to ensure quick implementation of the shell-feeding task. Based on composition of the agile shell-feeding system, hoist technology was studied. Working principles were discussed and the hydraulic pressure system of the hois was constructed. The hydraulic pressure cylinder...
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