Nginedatha ye-LiDAR - manje kwenzenjani?

Ngo isihloko ezithakazelisayo eshicilelwe muva ngu-David Mckittrick, lapho ekhuluma ngalokho okushiwo ulwazi ezanele zokwenza elihlobene ne ukusebenza LIDAR GIS futhi ebhekisele Global semephu njengoba ithuluzi ukusekelwa ngokucubungula idatha etholwe.

Ngemuva kokufunda le ndatshana, ngilande iGlobal Mapper ukuze ngiyidlale isikhashana, futhi kufanele ngivume ukuthi igcina lokho kusebenza kwalelo thuluzi ebesilazi nokuthi bekusebenziseka kanjani ukwenza amamodeli wendawo yedijithali kumafayili wombhalo we-xyz. Namuhla, lapho ukufinyelela kwimininingwane ye-LiDAR sekuya ngokukhokheleka kakhulu, akuyona into embi ukubheka izici okufanele zicatshangelwe lapho usebenza nabo futhi usho ukuthi i-Global Mapper yenza kahle kanjani. Lokho ngikugcizelela, kungishiye ngimangazwe yilokhu ebengikokuhlola; Ngobuso obuvuselelwe, uhlelo lugcina lokho kulula kokuvula idatha nokuyikhombisa kuziphakamiso ezilungiselelwe ngaphambili.

Ngolunye usuku, etafuleni leGeofumadas, ngangiyibona emehlweni kaDon H -omunye wabeluleki bami– ukukhanya okuphazamisayo emehlweni akhe lapho enikezwa khona umbhidi we-drone; bekuyisicelo sokuvuselela idatha ye-cadastral; Ngokudabukisa okukhulu kwadingeka ngiyilande efwini futhi ngikukhumbuze ukuthi emazweni amaningi asathuthuka azikho izimo ezincane zokusimama kwalobu buchwepheshe; nakuba ekugcineni sifinyelele ukuvumelana ngalokho okungenzeka ngendlela esebenzayo. Ukonakala kwale nqubo eminyakeni embalwa edlule kudale imizwa emikhulu ezinhlakeni ezithile zikahulumeni e-United States, manje isidluliselwa kwamanye amazwe anomongo weSpanishi, okungase kungene isifiso "sokugibela igagasi" lokusetshenziswa kwe- ubuchwepheshe obusha. , ukuthwebula idatha kodwa engazi ngempela ukuthi ngenzenjani ngayo.

Uma sibheka izindleko ezifunwa ukusetshenziswa kwe-LiDAR kuphrojekthi, sizobona ukuthi kubalulekile, uma sibheka lokho okubandakanya ukuqala ukuqoqwa kwedatha enkulu (uma sikhuluma nge-'Point Cloud Collection 'ikakhulukazi); ngisho nokubona ukuthi ukusetshenziswa kwayo kusinikeza umphumela osebenzayo nokonga isikhathi okukhulu. Isetshenziswe kahle, idatha ye-LiDAR isivumela ukuthi siqonde umhlaba ngendlela ehluke kakhulu kunalokho esikutholile ngemikhuba yendabuko yemephu Manje usungathola umbono wangempela usebenzisa amafomethi e-3D futhi ungaxhumana nedatha okwakhiwa ngayo amasu amasha wokuhlaziya.

Kuyini i-LiDAR

UDavide uthi kufanele: "Idatha ye-LiDD ayiyona umkhiqizo kodwa impahla eluhlaza"Ngabe yini eyenza umqondo wokuqala oyisihluthulelo, ngokubona kwethu, ukuqonda le ndaba. Eqinisweni, ukuthola idatha kungumnikelo ozosivumela, emva kokucubungula okwanele, ukuthola izinhlobo ezihlukahlukene ezintathu.

Kepha ukuze sicace kakhudlwana kudingeka sibuyele emuva sikhumbule ngesakhiwo nezici eziyisisekelo zedatha ye-LiDAR. I-LiDAR (isifinyezo se-Light and Range Detection) yifomethi ye-vector yamachashazi e-3D. Ifayela ngalinye noma isethi yedatha ye-LiDAR ngokuvamile iqukethe izigidi, noma ngisho nezigidigidi zamaphoyinti asatshalalisiwe futhi ahanjiswa ngezikhathi ezithile. Ukusondelana kwesikhala phakathi kwabo kuya ngokuthi idatha itholwe kanjani.

Idatha ye-LiDAR etholakalayo emphakathini iye yahlanganiswa, ikakhulukazi ngokusebenzisa ipulatifomu ehambelana nomoya esebenzisa ubuchwepheshe be-laser kanye ne-reception technology, ngohlelo lokusebenza oluhlangene nokusetshenziswa kwezinhlelo eziqondile nezindawo zokuhamba. Inani i-x, y, z elithathwe ngokungafani kwesikhathi elibalwa phakathi kokudluliselwa nokwamukelwa kwe-laser pulse kuboniswe iphuzu ngalinye.

Izindiza ezindizayo kancane zizokwenza ifu lamaphuzu lihlukaniswe kakhulu kunalinye elihamba ngezinyawo ngokushesha ezindaweni eziphakeme. Kuye ngenzwa esetshenziswa yizindiza noma i-drone, nokuthi idatha isebenze kanjani, izimfanelo ezengeziwe zombala, ukucabanga okukhulu, kanye nenani lokubuyela emuva, kungafakwa ukuboniswa nokuhlaziywa.

Yini engenziwa nge-LiDAR idatha

Ukucacisa kahle le LiDAR idatha asitholayo kwammangaza okuyinto ngokuvamile iba imodeli 3D ke khuluma isizukulwane Digital Elevation Model (DEM) noma, ukubeka / isizinda ngokuzenzekelayo Vector letigcogcwe ngaphambilini 3D derivatives amaphetheni weJiyomethri e matrix amaphuzu. Kungenzeka futhi, ngokushintsha ukumelwa fu iphuzu, ukuthola ulwazi okunenjongo, emelela izinhlobo ezahlukene ebusweni, ekuphakameni kwesihlobo iphuzu emhlabathini, noma ukushintshashintsha kwabantu amaphuzu, phakathi kwezinye izici.

Ukuhlela nokuhlunga kwedatha ye-LiDAR

Kuyinto evamile ukuthi amafayela wedatha atholakale afaka amaphuzu amaningi kunesidingo. Ngakho-ke, ngaphambi kokusebenzisa inqubo yokuhlunga efwini lephoyinti, kungcono ukuhlolisisa imethadatha yobunqamu. Isifinyezo sesibalo esitholiwe sizohlinzeka ngolwazi oludingekile mayelana nezici zefu ezizophakamisa izinqumo ezanele zokwenza inqubo yokuhlunga.

Ukuthuthukisa ikhwalithi yedatha ye-LiDAR

Ngemuva kokuqeda amaphuzu angadingeki, isinyathelo esilandelayo ukuthola futhi ukubuyisela kabusha lawo maphuzu omhlaba angazange ahlukaniswe ekuqaleni. Okusho ukuthi, kufanele silungise idatha. Lokhu kubaluleke kakhulu ukuze kuvezwe isinqumo esihle se-DEM.
Lapha sibheka ukuthi singakwazi ukwenza inqubo yokuhlunga eyanele kanye nokuhlelwa kabusha okulandelayo. Zombili izinqubo, ngokusobala eziyimishini, zibaluleke kakhulu emiphumeleni etholakala.

Kulokhu iGlobal Mapper yenza kahle kakhulu. Okungenani, esigabeni sokuhlela nokuhlunga. Futhi nokho kufanele kucatshangwe ukuthi ngokususa amaphuzu abanga umsindo, kunemininingwane ehlukaniswe njengobuso obungasizi ngalutho. Ngokusebenzisa i-Global Mapper, akunakwenzeka kuphela ukwenza ukususwa okwanele kwamaphoyinti angaphandle kwendawo yendawo yephrojekthi, kepha futhi nalawo angadingeki ngenxa yezici zawo, ngoba uhlelo lokusebenza lunezinketho eziningi zokuhlunga.
Manje ake sikhulume ngokulungiswa kwedatha. I-Global Mapper ihlanganisa izinqubo ezimbalwa ezididiyelwe lapho idatha ihlelwa khona ngokuzenzakalelayo futhi amaphuzu omhlaba angacatshangwa ekuqaleni abuyele ekugwemeni ukulahlekelwa idatha engase isebenziseke. Ngale ndlela iphesenti elilinganiselwe lamaphuzu angasetshenziswa ekwakhiweni kwe-DEM nesinqumo esiphezulu landa.

Isibonelo engisebenze nedatha ngaphambi nangemva kwesiphepho; ngokuqinisekile ngaphandle kokuba ne-wizzard, isofthiwe inezici cishe eziphakanyisiwe ekuphumeni komsebenzi wokuthola, imodeli, ukuhlunga, ukukhiqiza imodeli entsha.

Ngezinye izinqubo ezizenzakalelayo zokuhlela, izakhiwo zombuso, izihlahla nezintambo zingatholakala futhi ziphinde zenziwe kabusha, okuyinto isinyathelo sokuqala enkambeni yokukhipha izici.

Ukudalwa kwe-Digital Elevation Model

Ukwenza izinqubo zokuhlaziywa kwe-3D, cishe kuzo zonke izimo, ifu le-LiDAR iphuzu lizodinga ukuthi libe idatha ephumelelayo. Sisebenzisa inqubo ebizwa ngokuthi 'lattice' lapho inani elihambisana nephuzu ngalinye lomthamo (ngokuvamile inani lokuphakama) lisetshenziswa njengesizathu sokwenza imodeli eqinile ye-3D. Lo modeli ungabonisa indawo kuphela (imodeli yendawo ye-digital) noma indawo engaphezulu komhlaba, njenge-canopy yehlathi (i-digital surface model). Ukuhlukana phakathi kwalaba ababili kutholakala ekuhlungeni nasekukhetheni kwamaphuzu asetshenziselwa ukudala ubuso.

Uma sicabanga ukuthi iningi labasebenzisi be-LiDAR, inhloso eyinhloko ukukhiqizwa kwe-DTM (Digital Terrain Model), i-Global Mapper inikeza iqoqo elanele lamathuluzi wokuhlaziywa komhlaba, kufaka phakathi ukubalwa kwevolumu; ukusika nokugcwalisa ukusebenza; isizukulwane semigqa yemigqa; ukuhlukaniswa kwamanzi amaningi; kanye ne-line of analysis analysis.

Ukukhishwa kwezimfanelo

Ukwazi ukukhiqiza ukutholakala kwedatha enkulu kusuka efwini ledenser point kuchaza indlela entsha ebheke endleleni entsha yokucubungula idatha ye-LiDAR. Ukuhlaziywa kwamaphethini esakhiweni sejometri samaphoyinti aseduze kungaholela ekuchazweni kwamamodeli akhiwe, amelwe njengamapholigoni ayizinhlangothi ezintathu; izintambo zikagesi noma izintambo ngaphezulu komhlaba, ezimelwe njengemigqa yobukhulu obuthathu; kanye namaphuzu ezihlahla, atholakala esakhiweni esihlanganisiwe samaphoyinti abekwe njengotshani obuphakeme. Amathuluzi wokuhlanganisa we-Global Mapper amathuluzi afaka phakathi inketho yokukhethwa kwenkambiso lapho imigqa ye-3D ne-polygons ingakhiwa ngokulandela uchungechunge lokubukwa kwephrofayili okuhambisana nomzila ochazwe ngaphambilini. Leli thuluzi lingasetshenziselwa ukwakha imodeli enembile yesithathu yanoma yisiphi isakhiwo esinqunyiwe, njengengqenqemeni yomgwaqo emgwaqweni.

Isiphetho sikaDavid sisobala. Ukuba nedatha akuyona yonke into lapho usebenza ne-LiDAR; Ukuba nethuluzi lokuzicubungula ngendlela ephathekayo yilokho okuthuthukisa ukusetshenziswa kwalobu buchwepheshe.

Kuyinto ehlekisayo ukuthi ngesikhathi sokugcina ngibona lolu hlelo lokusebenza luse-2011, ngenguqulo ye-11. Bengivele ngenza umsebenzi neLiDAR kepha bekucindezela ngandlela thile ukusetshenziswa kwezinsizakusebenza, ngayeka ukubuka kusuka ku- Inguqulo ye-13 lapho lelo khono lithuthuke kancane. Kuyindaba yokuyilanda nokuyihlola, njengoba le nguqulo engu-18 ibonakala kimi ingenye yezindlela ezingcono kakhulu zesoftware ezisebenzisa cishe konke okungadingeka ukusebenzisa idatha ye-LiDAR.

iya ku- I-Global Mapper