Astronomical position without observed altitude of the celestial body

Lušić, Zvonimir

doi:10.1017/s037346331700073x

Cited by 4 publications

(4 citation statements)

References 6 publications

(7 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…The cause is most likely the poor internal tablet calculation of azimuth. The overall results of azimuth measurement show that smart devices cannot currently be used with the positioning method that relies only on the azimuth (i.e., the method explained in [10]).…”

Section: Results and Discussion / Rezultati I Raspravamentioning

confidence: 99%

Testing the Functionality and Applicability of Smart Devices for a Handheld Celestial Navigation System

Grm¹,

Grm²

2021

Naše more

View full text Add to dashboard Cite

In this paper, the functionality and applicability of smart devices for the purpose of handheld celestial navigation systems is investigated. The main instrument used to determine observer position (altitude measurements) in celestial navigation is the sextant. The use of a sextant and almanac or computer is a classical approach to determining the observer's celestial position. This approach has two significant limitations, firstly the time window for the measurements is short, and secondly, the view of the ocean horizon must be clear. With the use of smart devices, we can overcome these two obstacles and create a so-called handheld celestial navigation system. Currently, smart devices have very accurate sensors to measure various physical quantities such as acceleration, angular velocity, orientation, etc. We are particularly interested in validating the orientation sensor for measuring the altitude and azimuth of the celestial body. The altitude of the celestial body is the primary parameter in determining the celestial position using a sextant. The idea is to replace the sextant with a smart device to measure the altitude and possibly the azimuth of the celestial body. To test this idea, two types of experiments are designed. In the first, a system on a tripod to obtain the most accurate measurements possible is set. Such tests will provide detailed information about the accuracy of the smart device's sensors and its applicability in measuring altitude and azimuth. The test system will essentially resemble a theodolite device. In the second experiment, a hands-free measurement experiment that resembles a sextant to test the idea for practical use and functionality in the process of celestial positioning is set. The observed data show that the results of the measurements under controlled conditions are promising and within reasonable bounds for the accuracy of celestial positioning. Estimates of the position error by the graphical method are in the range of 10 Nm to 30 Nm. In order to obtain a fully functional stand-alone celestial positioning system, the proposed assembly needs to be improved through several unchallenging upgrades. A fully functional system can be considered as a cheap off-the-shelf handheld Celestial Navigational System (CNS).

show abstract

Section: Results and Discussion / Rezultati I Raspravamentioning

confidence: 99%

Testing the Functionality and Applicability of Smart Devices for a Handheld Celestial Navigation System

Grm¹,

Grm²

2021

Naše more

View full text Add to dashboard Cite

show abstract

“…Watchkeeping for Seafarers (STCW) amandemen 2010, mewajibkan semua perwira di kapal yang bertanggung jawab atas navigasi untuk bisa menentukan ketinggian benda langit, garis posisi atau Line of Position (LOP) dan posisi kapal. Di sisi lain dari STCW Amandemen 2010 tentang pendidikan dan Pelatihan terkait navigasi angkasa, mendorong penggunaan almanak elektronik dan perangkat lunak penghitungan lainnya [4].…”

Section: Berdasarkan the International Convention On Standard Of Training Certification Andunclassified

“…Benda-benda angkasa yang dimaksud antara lain adalah matahari, bulan, bintang dan planet-planet lainnya. Hal ini juga sejalan dengan pendapat yang menyatakan bahwa dasar dari semua metode yang direkomendasikan untuk memperoleh posisi dengan menggunakan benda langit adalah ketinggian yang diketahui dari benda angkasa yang sedang diamati [9]. Untuk itu perlu adanya sextant atau perangkat lain yang dapat mengukur ketinggian benda tersebut.…”

Section: Hasil Dan Pembahasanunclassified

Akurasi Nilai Tinggi Matahari Antara Perhitungan Daftar Ilmu Pelayaran (DIP) Dan Sight Reduction Table (SRT)

S.P¹,

Riyadi²,

Antoro³

et al. 2021

Saintara

View full text Add to dashboard Cite

Positioning with celestial bodies (celestial navigation) is the art of determining on the surface of the earth based on measurements of celestial bodies which have guided sailors for hundreds of years. Astronomical positioning methods or celestial body navigation are becoming increasingly obsolete and rarely used. The fact is that today, along with technological advances, seafarers prefer to use electronic navigation tools such as the Global Positioning System (GPS). The the International Convention on Standard of Training, Certification and Watchkeeping for Seafarers (STCW) amended 2011, requires all officers on board responsible for navigation to be able to determine the height of celestial bodies, the Line of Position (LOP) and the position of the ship. In general, there are 2 methods of determining the navigation position of celestial bodies, namely by calculating the Sight Reduction Table. This research discusses the accuracy of determining the height of the solar count by comparing the accuracy of the 2 methods. The method used is descriptive comparative based on field research with a qualitative approach. The technique of collecting data was done by means of observation, documentation and literature study. The purpose of this research is to test the accuracy of each calculation method, namely the calculation of the Sailing List (DIP) and the Sight Reduction Table (SRT). The results obtained in this study are the high calculation accuracy calculation method of calculating shipping science lists is more accurate with testing which is further discussed in this study.

show abstract

“…For obtaining the ship position when the horizon is invisible, the research [7] proposed an azimuth method based on the governing equations between the ship position and the great-circle azimuth of the celestial bodies. Meanwhile, the study [8] used the positioning equations through the spherical trigonometry. To improve the applicable ability of the azimuth method, a method combining the azimuth of celestial body with factors of ship route was investigated in [9].…”

Section: Introductionmentioning

confidence: 99%

A Theoretical Approach of Astronomical Ship Positioning Using a Single Celestial Body and Secant Technique

Nguyen¹

2020

IJFIS

View full text Add to dashboard Cite

In this article, a new approach to solve an astronomical ship position is proposed based on a single celestial body and secant technique. The mathematical equations relating the ship position to a celestial body are described using an altitude and an azimuth of celestial body. These equations are established using knowledge of spherical trigonometry. Numerical analysis is then employed based on secant method to solve the mathematical equations for the ship position. This technique uses the altitude and the azimuth simultaneously while existing methods need to observe the altitude either of two celestial bodies or of a single body at two different times. Therefore, it is worth to apply this proposed technique when there is only a single celestial body identified. To validate the feasibility of the proposed technique, two numerical examples were performed.

show abstract

Astronomical position without observed altitude of the celestial body

Cited by 4 publications

References 6 publications

Testing the Functionality and Applicability of Smart Devices for a Handheld Celestial Navigation System

Testing the Functionality and Applicability of Smart Devices for a Handheld Celestial Navigation System

Akurasi Nilai Tinggi Matahari Antara Perhitungan Daftar Ilmu Pelayaran (DIP) Dan Sight Reduction Table (SRT)

A Theoretical Approach of Astronomical Ship Positioning Using a Single Celestial Body and Secant Technique

Contact Info

Product

Resources

About