scholarly journals A route calculation for unmanned vessel

2021 ◽  
pp. 158-165
Author(s):  
А.С. Коренев ◽  
С.П. Хабаров ◽  
А.Г. Шпекторов
Keyword(s):  
Great Circle ◽  
Problem Solution ◽  
Alternate Route ◽  
Calculation Algorithm ◽  
Control Precision ◽  
Autonomous Mode ◽  
Electronic Chart ◽  
Unmanned Ship ◽  
Point Calculation ◽  
System Mapping

Рассматривается проблема определения маршрута движения безэкипажного судна с учетом жестких требований контроля положения и курса судна. Современные электронно-картографические навигационно-информационные системы в режиме управления траекторией определяют точку поворота для выхода на новый участок маршрута, что недостаточно для управления безэкипажным судном в автономном режиме. Для повышения точности предложено проводить расчет траектории движения безэкипажного судна в географических координатах c учетом движения судна по радиусу поворота между участками траектории без перевода в прямоугольную систему координат. Показано, что при движении в свободной акватории проблема может быть сведена к решению обратной геодезической задачи. Предложен универсальный алгоритм расчета траектории в виде сегментов дуг большого круга, позволяющий получить путевые точки маршрута с любой заданной точностью. В случае возникновения ограничений на движение между двумя участками по внутреннему радиусу необходимо рассчитать альтернативный маршрут обхода препятствия. Для данного случая предложен расчетный маневр, полученный на основе решения задачи Дубинса. Альтернативный маршрут формируется в виде последовательности криволинейных сегментов, соответствующих заданному радиусу поворота. Алгоритм расчета путевых точек позволяет получить траекторию обхода препятствия с любой степенью детализации. A route calculation problem for unmanned vessels is investigated according to the control position and course high requirements. Present day electronic chart display and information systems (ECDIS) operating on the track control regime provide wheel-of-point calculation to course changing. It is not enough to control unmanned ship on the route in the autonomous mode. To increase control precision a new route calculation routine is suggested. The routine provides route calculation in the geodesic coordinates without Cartesian reference system mapping. It is shown that in the empty water the routine can be reduced to an inverse survey computation. A universal route calculation algorithm providing great circle arc segmentation with any given accuracy is suggested. In the case of course changing restricted area, it is needed to calculate an alternate route for obstacle or collision avoidance. The algorithm of alternate route calculation based on Dubins problem solution is applied. The route is found as a sequence of great circle arcs according to the ship turn radius. The shown algorithm allows finding avoidance route waypoints with any given resolution.

Astronomical position without observed altitude of the celestial body

2017 ◽  
Vol 71 (2) ◽  
pp. 454-466
Author(s):  
Zvonimir Lušić
Keyword(s):  
Information System ◽  
Celestial Body ◽  
Precise Measurement ◽  
Dead Reckoning ◽  
Great Circle ◽  
Position Determination ◽  
Straight Line ◽  
Electronic Chart ◽  
Celestial Bodies ◽  
The Dead

The basis of all recommended methods for obtaining position by using celestial bodies is the known altitude of the celestial body being observed. Accordingly, it is necessary to have a sextant, classic or with an artificial horizon, or some other device that can measure altitude. However, there is a way to obtain position using astronomical navigation without determining the altitude of a celestial body, and this method will be analysed in this paper. The introduced method requires only precise measurement of the azimuth, and is based on determining two positions close to the dead reckoning position and lying on the isoazimuthal curve, i.e. a curve of the same great circle azimuths of a celestial body. Furthermore, the model assumes that a part of this curve, between the selected positions, can be replaced by a straight line. Special attention will be given to the analysis of errors of the line of position for various azimuth errors and various dead reckoning (assumed) positions. It will also be shown how a modern Electronic Chart Display and Information System (ECDIS) can help in approximate position determination, knowing only the azimuths of celestial bodies.

scholarly journals Enhanced Threshold Point Calculation Algorithm for Switch Fault Diagnosis in Grid Connected 3-Phase AC–DC PWM Converters

Energies ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1979
Author(s):  
Geun Wan Koo ◽  
DongMyoung Joo ◽  
Byoung Kuk Lee
Keyword(s):  
Fault Diagnosis ◽  
Theoretical Analysis ◽  
Load Condition ◽  
Test Bed ◽  
Calculation Algorithm ◽  
Point Calculation ◽  
Diagnosis Algorithm ◽  
Uninterruptible Power ◽  
Time Required ◽  
Threshold Point

The resilience of systems with alternating current (AC)–direct current (DC) converters has been investigated with the aim of improving switch fault diagnosis. To satisfy this aim, this paper proposes a switch fault diagnosis algorithm for three-phase AC–DC converters. The proposed algorithm operates using the phase current instead of the average current to reduce the calculation time required for fault switch detection. Moreover, a threshold point calculation method is derived using a theoretical analysis, which was lacking in previous research. Using the calculated threshold point, a switch fault diagnosis algorithm is obtained to detect faults independent of the load condition. Using the proposed algorithm, switch faults can be detected within 4 ms, which is the recommended value for uninterruptible power supply (UPS). The theoretical analysis, the operating principle, and the experimental results on a 3-kW grid-tied AC–DC converter test-bed are presented herein, which verify the performance of the proposed algorithm.

Abstract #300 Evaluation of the Accuracy of an Implantable CGM System with an Updated Glucose Calculation Algorithm

2019 ◽  
Vol 25 ◽  
pp. 125
Author(s):  
Mark Christiansen ◽  
Timothy Bailey ◽  
Leslie Klaff ◽  
Ron Brazg ◽  
Anna Chang ◽  
...  
Keyword(s):  
Calculation Algorithm

In Search of Somatic Precursors of Spontaneous Insight

2018 ◽  
Vol 32 (3) ◽  
pp. 97-105 ◽  
Author(s):  
Wangbing Shen ◽  
Yuan Yuan ◽  
Chaoying Tang ◽  
Chunhua Shi ◽  
Chang Liu ◽  
...  
Keyword(s):  
Problem Solving ◽  
Direct Evidence ◽  
Electrodermal Activity ◽  
Cardiovascular Responses ◽  
Solution Time ◽  
Problem Solution ◽  
Insight Problem ◽  
Creative Insight ◽  
Insight Problem Solving ◽  
Analytic Problem

Abstract. A considerable number of behavioral and neuroscientific studies on insight problem solving have revealed behavioral and neural correlates of the dynamic insight process; however, somatic correlates, particularly somatic precursors of creative insight, remain undetermined. To characterize the somatic precursor of spontaneous insight, 22 healthy volunteers were recruited to solve the compound remote associate (CRA) task in which a problem can be solved by either an insight or an analytic strategy. The participants’ peripheral nervous activities, particularly electrodermal and cardiovascular responses, were continuously monitored and separately measured. The results revealed a greater skin conductance magnitude for insight trials than for non-insight trials in the 4-s time span prior to problem solutions and two marginally significant correlations between pre-solution heart rate variability (HRV) and the solution time of insight trials. Our findings provide the first direct evidence that spontaneous insight in problem solving is a somatically peculiar process that is distinct from the stepwise process of analytic problem solving and can be represented by a special somatic precursor, which is a stronger pre-solution electrodermal activity and a correlation between problem solution time and certain HRV indicators such as the root mean square successive difference (RMSSD).

"Multiple Transfer Paradigms following Discrimination Problem Solution in Monkeys": Erratum.

1969 ◽  
Vol 67 (2, Pt.1) ◽  
pp. 144-144
Author(s):  
Michael Sledjeski ◽  
Gilbert M. French
Keyword(s):  
Discrimination Problem ◽  
Problem Solution

Charts for Great Circle Sailing

1885 ◽  
Vol 20 (501supp) ◽  
pp. 7991-7991
Author(s):  
Richard A. Proctor
Keyword(s):  
Great Circle

Hydrostatic Fiber Optic Liquid Level Sensor with position sensitive detector

Metrologiya ◽  
2020 ◽  
pp. 38-51
Author(s):  
V. N. Astapov ◽  
I. N. Kozlova
Keyword(s):  
Fiber Optic ◽  
Effective Area ◽  
Raw Material ◽  
Position Sensitive Detector ◽  
Fiber Optic Sensor ◽  
Liquid Level ◽  
Problem Solution ◽  
Sensitive Detector ◽  
Position Sensitive ◽  
Triangulation Sensor

This article presents the rationale and methodology for developing an intrinsically safe device, namely, a hydrostatic fiber optic sensor with a position-sensitive detector for monitoring the level of oil products in large-capacity tanks at oil depots and during pumping in a raw material warehouses. This device suitable for continuous monitoring of the liquid level, based on the measurement of a hydrostatic column of liquid with automatic offset of changes in the density of the liquid. Offset is carried out by means of a displacer (a fully submerged float), inside which a housing with a position-sensitive detector (PSD) is integrated. Theoretical validation of the bellows suspension usage for a displacer is given. During filling a container with a liquid whose level is measured, liquid bellows, the movement of which is recorded by an optical triangulation sensor using the reflected infrared ray incident on the bottom of the bellows. The principle of the triangulation sensor operation is based on the geometric properties of the triangles. The pulses of infrared radiation come through a fiber optic cable. In order to measure the movement of the surface (the bottom of the bellows) by measuring the movement of the reflected beam, a position-sensitive detector is used, which is located in a remote controller. In this device for the intrinsic safety problem solution, optical inputs of a fiber optic flat cable are located in the active zone of the sensor, which is connected to the optical inputs of a position-sensitive detector, operated on the principles of photoelectric effect. The light spot moving along the sensitive zone and converted by the detector into a one-dimensional signal proportional to the distance to the object. hydrostatically applies pressure over the entire effective area of the measuring

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