Sun Shadow Position Based on the Sundial
WU Junbin
WU Sheng
WU Xingjiao
Abstract：Based on the principle of the ancient sundial ,throuth the shadow of the sun to achieve positioning ,according to the theory of astronomy ,the sun's data is calculated ,such as elevation angle ,azimuth angle and shadow forming princi‐ple .And the data of the sundial shadow is calculated at each moment between sunrise and sunset ,such as length and azi‐muth .Then the relationship of the functions between shadow of the sun and latitude‐longitude is gotten .Then ,in the process of using backstepping method to solving the problem ,the least squares method is used to obtain shadow‐length in noon local time and Beijing time ,and finally the problem is solved by the functions between shadow of the sun and latitude‐longitude .In this article ,the emulation and simulation are carried out through JAVA program to verify the results and proves the truth of these method .
Keywords：shadow positioningsundial projection principleleast square methodJava simulation
Publication Date：2016-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：4( 393-395,444 )