Kuzindikira Kutali kwa LiDAR: Mfundo, Kugwiritsa Ntchito, Zinthu Zaulere ndi Mapulogalamu

Masensa a Airborne LiDARakhoza kujambula mfundo zinazake kuchokera ku laser pulse, yomwe imadziwika kuti discrete return measurements, kapena kulemba chizindikiro chonse pamene chikubwerera, chotchedwa full-waveform, pa nthawi yokhazikika monga 1 ns (yomwe imaphimba pafupifupi 15 cm). Full-waveform LiDAR imagwiritsidwa ntchito kwambiri mu nkhalango, pomwe discrete return LiDAR ili ndi ntchito zambiri m'magawo osiyanasiyana. Nkhaniyi ikufotokoza makamaka za discrete return LiDAR ndi momwe imagwiritsidwira ntchito. Mu chaputala chino, tikambirana mitu ingapo yofunika kwambiri yokhudza LiDAR, kuphatikizapo zigawo zake zoyambira, momwe imagwirira ntchito, kulondola kwake, machitidwe ake, ndi zinthu zomwe zilipo.

Zigawo Zoyambira za LiDAR

Makina a LiDAR ochokera pansi nthawi zambiri amagwiritsa ntchito ma laser okhala ndi mafunde apakati pa 500–600 nm, pomwe makina a LiDAR oyenda m'mlengalenga amagwiritsa ntchito ma laser okhala ndi mafunde aatali, kuyambira 1000–1600 nm. Kukhazikitsa kwa LiDAR yoyenda m'mlengalenga kumaphatikizapo sikelo ya laser, gawo loyezera mtunda (gawo lozungulira), ndi machitidwe owongolera, kuyang'anira, ndi kujambula. Imaphatikizanso Differential Global Positioning System (DGPS) ndi Inertial Measurement Unit (IMU), nthawi zambiri imaphatikizidwa mu dongosolo limodzi lodziwika kuti malo ndi njira yowunikira. Dongosololi limapereka malo enieni (longitude, latitude, ndi altitude) ndi deta yowunikira (roll, pitch, ndi heading).

 Mapangidwe omwe laser imasanthula dera amatha kusiyana, kuphatikiza njira zozungulira, zofanana, kapena zozungulira. Kuphatikiza kwa deta ya DGPS ndi IMU, pamodzi ndi deta yowunikira ndi magawo oyika, kumalola dongosololi kuti ligwiritse ntchito molondola mfundo za laser zomwe zasonkhanitsidwa. Kenako mfundo izi zimapatsidwa ma coordinates (x, y, z) mu dongosolo logwirizanitsa malo pogwiritsa ntchito World Geodetic System ya 1984 (WGS84) datum.

Momwe LiDARKuzindikira KwakutaliNtchitoFotokozani m'njira yosavuta

Dongosolo la LiDAR limatulutsa ma pulse a laser ofulumira kupita ku chinthu kapena pamwamba pake.

Ma pulse a laser amaonekera kuchokera pa chandamale ndikubwerera ku sensa ya LiDAR.

Sensa imayesa molondola nthawi yomwe imatenga kuti kugunda kulikonse kuyende kupita ku cholinga ndi kubwerera.

Pogwiritsa ntchito liwiro la kuwala ndi nthawi yoyendera, mtunda wopita ku cholinga umawerengedwa.

Pogwirizana ndi malo ndi deta yolunjika kuchokera ku masensa a GPS ndi IMU, ma coordinates olondola a 3D a kuwala kwa laser amatsimikiziridwa.

Izi zimapangitsa kuti mtambo wokhuthala wa 3D ukhale woimira pamwamba kapena chinthu chomwe chaskenidwa.

Mfundo Yachilengedwe ya LiDAR

Makina a LiDAR amagwiritsa ntchito mitundu iwiri ya ma laser: mafunde oyendetsedwa ndi mpweya ndi mafunde osalekeza. Makina a LiDAR oyendetsedwa ndi mpweya amagwira ntchito potumiza kuwala kwaufupi kenako nkuyeza nthawi yomwe kuwalaku kumayenda kupita ku cholinga ndikubwerera kwa wolandila. Kuyeza kumeneku kwa nthawi yobwerera kumathandiza kudziwa mtunda wopita ku cholinga. Chitsanzo chikuwonetsedwa pachithunzi pomwe ma amplitude a chizindikiro cha kuwala chotumizidwa (AT) ndi chizindikiro cha kuwala cholandiridwa (AR) amawonetsedwa. Equation yoyambira yomwe imagwiritsidwa ntchito mu dongosololi imakhudza liwiro la kuwala (c) ndi mtunda wopita ku cholinga (R), zomwe zimathandiza dongosololi kuwerengera mtunda kutengera nthawi yomwe kuwalako kumatenga kuti kubwerere.