Ngingakuthuthukisa kanjani ukunemba kokuphakama ku-TwoNav GPS?

Isingeniso

Kusukela ekuqaleni kuka-2021, i-IGN ibinikeza ukufinyelela kwamahhala kweminye yedatha yayo:

• Amamephu we-IGN's TOP 25 awamahhala, nokho inguqulo ye-Map etholakala ku-Géoporttail imahhala.
• Imininingo egciniwe ye-altimeter ye-IGN 5 x 5 m itholakala mahhala. Lezi zingosi zolwazi zivumela ukudalwa kwemodeli yendawo yedijithali, i.e. imephu yobude enokulungiswa okuvundlile okungu-5 mx 5 m noma 1 mx 1 m ngokulungiswa okuqondile okungu-1 m. Noma incazelo enhle yabasebenzisi esiyiyona.

Le ndatshana ekwifomu lokufundisa ihloselwe ngokukhethekile abasebenzisi besoftware ye-GPS TwoNav kanye ne-Land.

Akunakwenzeka ukuba nomthelela kudatha yokuphakama kwe-Garmin GPS ngalesi sikhathi.

Iyini imodeli yokuphakama kwedijithali (DTM)

Imodeli yokuphakama kwedijithali (i-DEM) iwumfanekiso onezinhlangothi ezintathu womkhathi odalwe kusukela kudatha yokuphakama. Ukunemba kwefayela lokuphakama (DEM) kuncike kulokhu:

• Ikhwalithi yedatha yokuphakama (ukunemba nezindlela ezisetshenziselwa ukuhlola),
• Usayizi weyunithi yeseli (pixel),
• Mayelana nokunemba okuvundlile kokwenziwa kwasendaweni kwalawa magridi,
• Ukunemba kwendawo yakho kanye nekhwalithi ye-GPS yakho, iwashi elixhunyiwe noma i-smartphone yakho.

I-slab noma ithayela elisuka kusizindalwazi se-IGN Altimetric. Ithayela elingu-5 km x 5 km, elihlanganisa amaseli angu-1000 × 1000 noma amaseli angu-5 mx 5 m (Saint Gobain Aisne Forest). Lesi sikrini sivezwa kumephu yesisekelo ye-OSM.

I-DEM iyifayela elichaza inani lobude bephoyinti eliphakathi nendawo yegridi, kanye nendawo yonke yegridi ekuphakameni okufanayo.

Isibonelo, ifayela lomnyango le-Aisne BD Alti IGN elingu-5 x 5 m (umnyango okhethwe ngenxa yobukhulu bawo) lingaphansi kwamathayili angu-400.

Igridi ngayinye ikhonjwa ngeqoqo lezixhumanisi ze-latitude kanye ne-longitude.

Uma usayizi wegridi umncane, idatha yokuphakama inembe kakhulu. Imininingwane yokuphakama emincane kunosayizi wemeshi (ukulungiswa) ishaywa indiva.

Uma umncane usayizi wemeshi, uphakeme ukunemba, kodwa ifayela lizoba likhulu, ngakho-ke kuzothatha isikhala sememori esengeziwe futhi kube nzima ukusicubungula, okungenzeka kubambezele eminye imisebenzi yokucubungula.

Usayizi wefayela le-DEM lomnyango cishe u-1Mo ku-25m x 25m, 120Mo okungu-5m x 5m.

Ama-DEM asetshenziswa izinhlelo zokusebenza eziningi, amawebhusayithi, i-GPS nama-smartphones abathengi asuka kudatha yamahhala yomhlaba wonke enikezwe i-NASA.

Ukuhleleka kokunemba kwe-NASA DEM kuwusayizi weseli ongu-60m x 90m kanye nesinyathelo sobude obungu-30m. Lawa amafayela aluhlaza, awalungiswanga, futhi ngokuvamile idatha iyahlanganiswa, ukunemba kumaphakathi, kungase kube mkhulu. amaphutha.

Lesi esinye sezizathu zokunemba okuqondile kwe-GPS, okuchaza umehluko ekuphakameni okuqashelwe ithrekhi, kuye ngewebhusayithi esingathwa kuyo, i-GPS noma i-smartphone eqophe umehluko ekuphakameni.

• I-Sonny MNT (bheka kamuva kulo mhlahlandlela) itholakala mahhala eYurophu ngosayizi weseli olinganiselwa ku-25m x 30m. Isebenzisa imithombo yedatha enembe kakhulu kune-NASA MNT futhi iye yasebenza ukuze ibhekane neziphazamisi ezinkulu. I-DEM enembile uma kuqhathaniswa elungele ukuhamba ngebhayisikili ezintabeni, esebenza kahle ezweni lonke laseYurophu.

Esithombeni esingenhla, ithayela le-altimetric (MNT BD Alti IGN 5 x 5) elimboze izinqwaba ze-slag (eduze ne-Valenciennes) liguqulelwe laba imigqa yamakhonkolo ehlukaniswe ngamamitha angu-2,5 futhi yabekwa phezulu kumephu ye-IGN. Isithombe sikuvumela ukuthi "ukholise" ngekhwalithi yale DEM.

• I-IGN DEM engu-5 x 5 m inokulungiswa okuvundlile (usayizi weseli) ka-5 x 5 m kanye nokulungiswa okuqondile okungu-1 m. Le DEM inikeza ukuphakama kwendawo; ubude bezinto zengqalasizinda (izakhiwo, amabhuloho, uthango, njll.) akunakwa. Ehlathini, lokhu ubude bomhlaba phansi kwezihlahla, ubuso bamanzi buwubuso bogu lwawo wonke amachibi amakhulu kunehektha elilodwa.

Ukuhlanganiswa nokufakwa kwe-DEM

Ukuze uhambe ngokushesha: Umsebenzisi we-GPS we-TwoNav uhlanganise imodeli yendawo yedijithali emboza i-France esebenzisa idatha ye-IGN engu-5 x 5 m. Lokhu kungalandwa ngesifunda kusayithi lamahhala: CDEM 5 m (RGEALTI).

Kumsebenzisi, uhlolo olulungile lokuhlola ukwethembeka kwe-“DEM” ukubonakala kwendawo yechibi nge-3D.

Ngaphansi kwechibi le-Forges endala (i-Ardennes), ekhonjiswe ku-3D ngu-BD Alti IGN ngenhla kanye no-BD Alti Sonny ngezansi. Siyabona ukuthi kukhona izinga.

Amamephu e-altimeter e-CDEM ahlinzekwa yi-TwoNav njengezinga le-GPS noma isofthiwe ye-LAND awathembekile kakhulu.

Ngakho, lesi "sifundo" sinikeza umhlahlandlela womsebenzisi wokulanda "amathayili" edatha ethembekile ye-altimetry yesofthiwe ye-TwoNav GPS kanye ne-LAND.

Idatha itholakala mahhala:

• Yonke iYurophu: I-Sonny Altimetry Database,
• France: IGN altimetry database.

Ungakha ifayela elimboze izwe, umnyango, noma indawo yendawo kuphela (I-Slab / tile / Pellet) ukuze ulondoloze imemori esebenzisekayo noma usebenzise amafayela amancane.

Sonny Altimeters Database

Amamodeli angu-1 '' ahlukaniswe abe izingxenyana zefayela ezingu-1 ° x1 ° futhi atholakala ngefomethi ye-SRTM (.hgt) enosayizi weseli ongu-22 × 31 m kuye ngokuthi i-latitude, ifomethi esetshenziswa emhlabeni wonke futhi esetshenziswa ezinhlelweni eziningi. Aqokwa yizixhumanisi zawo, isibonelo i-N43E004 (43 ° latitude enyakatho, 4 ° i-east longitude).

inqubo

1. Xhuma kusayithi https://data.opendataportal.at/dataset/dtm-france

2. Landa amathayili ahambisana nezwe elikhethiwe noma umkhakha wendawo.

3. Khipha amafayela e-.HGT kumafayela alandiwe we-.ZIP.

4. Ku-LAND, layisha ifayela ngalinye le-.HGT

5. E-LAND, wonke ama-hgts afunekayo avuliwe, vala okunye.

6. Sicela wenze okuthi "Hlanganisa lawa ma-DEMS", isikhathi sokuhlanganisa singaba side kuye ngenani lamathayela ozoqoqwa (khetha isandiso se-cdem) sefayela elithi .CDEM elingasetshenziswa ku-Twonav GPS.

Imephu ye-OSM "tile" kanye ne-MNT "tile" ku-LAND, yonke into iyaphatheka ku-GPS futhi 100% mahhala!

I-IGN Altimetry Database

Lesi sizindalwazi siqukethe uhla lwemibhalo ngomnyango.

inqubo

1. Xhuma kusayithi le-Geoservices. Uma lesi sixhumanisi singasebenzi: isiphequluli sakho "asinakho ukufinyelela kwe-FTP": ungathuki! Igayidi yomsebenzisi:
   • Kumphathi wefayela lakho:
   • chofoza kwesokudla "le PC"
   • chofoza kwesokudla "engeza indawo yenethiwekhi"
   • Faka ikheli "ftp: // RGE_ALTI_ext: [e-mail]" "ngaphandle" ";
   • Yisho lokhu kufinyelela ukuze uyibone njenge-IGN geoservice
   • Qeda inqubo
   • Linda imizuzu embalwa ukuze uhlu lwamafayela lubuyekezwe (kuzothatha amaminithi ambalwa)
2. Manje usungakwazi ukufinyelela idatha ye-IGN:
   • Chofoza kwesokudla kufayela ledatha ofuna ukulikopisha.
   • Bese FAKA kumkhombandlela oqondiwe
   • Izikhathi zokushaja zingaba zinde!

Lesi sithombe sibonisa ukungeniswa kwesizindalwazi se-Vaucluse 5m x 5m altimeters. Chofoza kwesokudla efayeleni, bese ukopisha kufolda bese ulinda ukudawuniloda.

Ngemva kokukhipha ifayela elithi "zipped", kutholakala isakhiwo somuthi. Idatha ihambisana namafayela edatha angaba ngu-400 (amathayela) 5 km x 5 km noma 1000 × 1000 amaseli 5 m x 5 m ngefomethi ye-asc (ifomethi yombhalo) yomnyango.

I-multi-tile disc ivala kakhulu ithrekhi ye-MTB.

Iseli ngalinye elingu-5x5 km likhonjwa isethi ye-Lambert izixhumanisi ezingama-93.

Izixhumanisi ze-UTM ekhoneni elingaphezulu kwesokunxele laleli thayela noma amathayela athi x = 52 6940 kanye no-y = 5494 775:

• 775: izinga lekholomu (770, 775, 780, ...) kumephu
• 6940: Izinga lomugqa emephini

3. Izwe Lomdanso

4. Esinyathelweni esilandelayo, thola idatha kunkomba "yedatha", khetha kuphela ifayela lokuqala:

5. Vula bese uqinisekisa, iwindi elingezansi lizovuleka, qaphela, lesi isinyathelo esibucayi kakhulu :

Khetha i-projection Lambert-93 ne-Datum RGF 93 bese uqoka ibhokisi ekhoneni elingezansi kwesokunxele.

Izingcaphuno zomhlaba namafomethi wedatha evela kuthayela * .asc, okungathatha isikhashana.

Ngemva kokudala ama-slabs asuka ku-DEM ngefomethi ye-SRTM (HGT/DEM), maningi njengoba kunamafayela ngefomethi ye-* .asc.

6. Umhlaba ikuvumela ukuthi "uwahlanganise" abe ifayela elilodwa le-DEM noma ngethayela noma i-granule ukuze ihambisane nezidingo zakho (khumbula ukuthi usayizi wefayela unganciphisa ukucutshungulwa kwe-GPS)

Ukuze kube lula ukusetshenziswa, kungcono (uma uthanda) ukumboza wonke amakhadi avuliwe kuqala.

Kumenyu yemephu (bona ngezansi) vula wonke amafayela ngefomethi ye-* .hdr (encane kakhulu) yohla lwemibhalo lwedatha egciniwe engenisiwe (njengokusebenza kwangaphambilini)

Umhlaba uvula amafayela e-HDR, i-DEM yomnyango iyalayishwa futhi ingasetshenziswa

7. Lapha ungasebenzisa i-Ardennes DEM (i-bump map), ukwenza kube lula ukuyisebenzisa, sizoyihlanganisa ibe ifayela elilodwa.

Imenyu yohlu:

Hlanganisa lawa ma-DEM

Khetha ifomethi * .cdem bese uqamba ifayela elithi DEM.

Ukuhlanganisa kuzothatha isikhathi esincane, amafayela angaphezu kuka-21 adinga ukuhlanganiswa. Ngakho-ke izincomo zokusebenza ngesisekelo sezinhlamvu ze-MNT ezimboza izinkundla zakho zokudlala.

Imodeli yedijithali yendawo yase-Ardennes esiyidalile, vele uvule lelo fayela lemephu ye-IGN Geoportal njengoba kukhonjisiwe ngezansi, isibonelo.

Ukuhlola kwenziwa ngokuvula ngokuqondile ithrekhi ye-UtagawaVTT ethi “Château de Linchamp” ekhonjiswe ekuqaleni umehluko wobude obungu-997m, 981m ne-Sonny DTM (inqubo yangaphambilini) kanye no-1034m lapho i-Land ithatha indawo yobude endaweni ngayinye ngobude be-DTM obungu-5mx5m. .

Ukubalwa komehluko weleveli ngokufingqa imigqa yekhonta kumephu ye-IGN kukhombisa umehluko ezingeni lika-1070 m, okusho ukuthi, umehluko ongu-3%, okulungile impela.

Inani lika-1070 lihlala lilinganisa ngoba akuyona into encane ukubala amajika kumephu ngokukhululeka.

Ukusebenzisa ifayela le-altimetry

Amafayela e-MNT.cdem angasetshenziswa yi-LAND ukuze kukhishwe ukuphakama, ukubala ukuphakama, umthambeka, amathrekhi we-waypoint, nokuningi; futhi kuwo wonke amadivaysi e-GPS e-TwoNav kwanele ukubeka ifayela kuhla lwemibhalo lwemephu bese ulukhetha njenge-map.cdem.

Isihloko sebhulogi mayelana nokuphakama okungaqondile kwembula inkinga yomehluko we-altimetry nokuphakama kusetshenziswa i-GPS, isimiso singadluliselwa kumawashi e-GPS kanye nezinhlelo zokusebenza ze-smartphone.

Abakhiqizi basebenzisa izindlela ezimbalwa ukuze "basule" ukungalungi okwethulwe kulesi sihloko, ukuhlunga (isilinganiso esihambayo) idatha yokuphakama, besebenzisa inzwa ye-barometric noma imodeli yendawo yedijithali.

Ukuphakama kwe-GPS “kunomsindo”, okungukuthi kuyaguquguquka eduze kwenani elimaphakathi, ukuphakama kwe-barometric kuncike ku-vagaries yokucindezela kwe-barometric kanye nezinga lokushisa, ngakho isimo sezulu kanye namafayela e-DEM angakwazi ukunemba.

I-Hybridization ye-barometer ene-GPS noma i-DEM isuselwe kumgomo olandelayo:

• Ngokuhamba kwesikhathi eside, ukuguqulwa kokuphakama kwe-barometric kuncike ezimweni zezulu (ingcindezi kanye nezinga lokushisa),
• Ngokuhamba kwesikhathi eside, amaphutha okuphakama kwe-GPS ayahlungwa,
• Isikhathi eside, amaphutha e-DEM afana nomsindo, ngakho ayahlungwa.

I-Hybridization imayelana nokubala i-avareji ye-GPS noma i-DEM altitude kanye nokukhipha ushintsho lwe-altitude kuyo.

Isibonelo, phakathi nemizuzu engu-30 yokugcina, ukuphakama komsindo ohlungiwe (i-GPS noma i-MNT) kukhuphuke ngamamitha angu-100; nokho, phakathi nenkathi efanayo, ukuphakama okuboniswe yi-barometer kukhuphuke ngamamitha angu-150.

Ngokunengqondo, ushintsho lobude kufanele lufane. Ulwazi lwezakhiwo zalezi zinzwa lwenza kube nokwenzeka "ukulungisa" i-barometer -50 m.

Ngokuvamile kumodi ye-Baro + GPS noma ye-3D, ukuphakama kwe-barometer kuyalungiswa, njengoba umhambi noma umqwali engenza ngesandla, ngokubhekisela kumephu ye-IGN.

Ngokucacile, i-GPS yakamuva noma i-smartphone yakamuva (ikhwalithi enhle) ikuthola (FIX) ngokunemba okungu-3,5 m endizeni evundlile izikhathi ezingu-90 kwezingu-100 lapho izimo zokwamukela zilungile.

Lokhu “kusebenza” okuvundlile kuhambisana nosayizi wemeshi ongu-5 mx 5 m noma 25 mx 25 m futhi ukusetshenziswa kwalawa ma-DTM kuvumela ukunemba okuhle kokuma.

I-DEM ibonisa ukuphakama komhlabathi, isibonelo uma uwela i-Tarn Valley ku-Millau viaduct, ithrekhi erekhodwe ku-DEM kufanele ikuyise phansi esigodini, ngisho noma indlela isala ku-viaduct platform. ...

Esinye isibonelo, uma uhamba ngebhayisikili lezintaba noma uhamba endaweni ewumqansa, ukunemba kwe-GPS okuvundlile kuyawohloka ngenxa yokufihla ubuso noma imiphumela ye-multipath; khona-ke ukuphakama okunikezwe ku-FIX kuzohambisana nokuphakama kwe-slab eseduze noma ekude kakhulu, ngakho-ke kuya phezulu noma phansi kwesigodi.

Endabeni yefayela elakhiwe ngamagridi wendawo enkulu, ukuphakama kuzothambekela esilinganisweni phakathi kokuphansi kwesigodi nangaphezulu!

Kulezi zibonelo ezimbili ezeqisayo kodwa ezijwayelekile, umehluko okhulayo wobude uzochezuka kancane kancane enanini langempela.

Iziphakamiso zokusetshenziswa

Ukuze ugweme imiphumela emibi:

• Linganisa ibharomitha ye-GPS ekuphakameni kwendawo yakho yokuqala ngaphambi nje kokuhamba (kunconywe yibo bonke abakhiqizi be-GPS),
• vumela i-GPS yakho yenze IZILUNGISO ezimbalwa ngaphambi kokuqala ukulandelela ukuze ukunemba kokuma kufane,
• khetha ukuxutshwa: ukubala kokuphakama = Barometer + GPS noma Barometer + 3D.

Uma ukuphakama kwethrekhi yakho kuvumelaniswe ku-DEM, uzoba nezibalo ezinembe kakhulu zokuphakama nemithambeka njengasesithombeni esingezansi, lapho umehluko uyimitha elingu-1 kuphela.

• I-GPS Trail 2 (isithombe esehlisiwe esingu-72dpi, isikrini se-GPS esingu-200dpi)
• Isendlalelo se-raster nemephu yevekhtha ye-OSM
• Isikali 1: 10
• I-CDEM 5mx5m BD Alti IGN shading igcizelela ubude ngokunyuka okungu-1m.

Isithombe esingezansi siqhathanisa iphrofayili yamathrekhi afanayo angu-30km (odumo olufanayo), ukuphakama kwelinye kwavunyelaniswa ne-IGN DEM kanti enye ne-Sonny DEM, umzila oqhutshwa nge-baro + hybrid mode 3d.

• Ukuphakama kumephu ye-IGN: 275 m.
• I-Altitude ibalwa nge-GPS kumodi ye-Hybrid Baro + 3D: 295 m (+ 7%)
• I-Altitude ibalwa nge-GPS kumodi ye-Hybrid Baro + GPS: 297 m (+ 8%).
• Ukukhuphuka okuvunyelanisiwe ku-IGN MNT: 271 m (-1,4%)
• Umqansa ovumelanisiwe ku-Sonny MNT: 255 m (-7%)

"Iqiniso" cishe lingaphandle kwe-275m IGN ngenxa yelungiselelo lejika.

Isibonelo sokulinganisa okuzenzakalelayo (isinxephezelo) se-altimeter ye-barometric ye-GPS phakathi nomzila oboniswe ngenhla (Ifayela lokungena langempela elivela ku-GPS):

• Akukho ukunqwabelana okuqondile kokubala umehluko wobude: 5 m, (I-Parametrization iyafana namajika emephu ye-IGN),
• Ukuphakama ngesikhathi sokulinganisa / ukusetha kabusha:
  • I-GPS 113.7 m,
  • I-altimeter ye-Barometric 115.0 m,
  • Ubude be-MNT 110.2 m (Carte IGN 110 m),
• Ukuphindaphinda (Isikhathi Sokukhokha): imizuzu engama-30
• Ukulungiswa kwe-Barometric emaminithini angu-30 alandelayo: - 0.001297