search query: @keyword quality assurance / total: 53
reference: 9 / 53
« previous | next »
Author:Rantanen, Jesperi
Title:Ilmakolmioinnin laadunvalvonta fotogrammetristen pintamallien ja laserkeilausaineiston avulla
Quality assurance of aerial triangulation using photogrammetric surface models and laser scanning data
Publication type:Master's thesis
Publication year:2014
Pages:vii + 62      Language:   fin
Department/School:Insinööritieteiden korkeakoulu
Main subject:Fotogrammetria ja kaukokartoitus   (M3006)
Supervisor:Haggrén, Henrik
Instructor:Ilves, Risto
Electronic version URL: http://urn.fi/URN:NBN:fi:aalto-201408152398
OEVS:
Electronic archive copy is available via Aalto Thesis Database.
Instructions

Reading digital theses in the closed network of the Aalto University Harald Herlin Learning Centre

In the closed network of Learning Centre you can read digital and digitized theses not available in the open network.

The Learning Centre contact details and opening hours: https://learningcentre.aalto.fi/en/harald-herlin-learning-centre/

You can read theses on the Learning Centre customer computers, which are available on all floors.

Logging on to the customer computers

  • Aalto University staff members log on to the customer computer using the Aalto username and password.
  • Other customers log on using a shared username and password.

Opening a thesis

  • On the desktop of the customer computers, you will find an icon titled:

    Aalto Thesis Database

  • Click on the icon to search for and open the thesis you are looking for from Aaltodoc database. You can find the thesis file by clicking the link on the OEV or OEVS field.

Reading the thesis

  • You can either print the thesis or read it on the customer computer screen.
  • You cannot save the thesis file on a flash drive or email it.
  • You cannot copy text or images from the file.
  • You cannot edit the file.

Printing the thesis

  • You can print the thesis for your personal study or research use.
  • Aalto University students and staff members may print black-and-white prints on the PrintingPoint devices when using the computer with personal Aalto username and password. Color printing is possible using the printer u90203-psc3, which is located near the customer service. Color printing is subject to a charge to Aalto University students and staff members.
  • Other customers can use the printer u90203-psc3. All printing is subject to a charge to non-University members.
Location:P1 Ark Aalto  1425   | Archive
Keywords:aerial triangulation
laser scanning
quality assurance
terrain surface model
ilmakolmiointi
laserkeilaus
laadunvalvonta
maastonpintamalli
Abstract (eng):Aerial triangulation is used to solve attitude and position information of aerial image block.
Possible errors left after the triangulation were studied by comparing a photogrammetric surface model made from aerial mapping images to surface model made using laser scanning.
Literature review studied the theory of these surface models and different algorithms used to create them.
Several methods and areas are tested to compute a difference between the two surface models but there is a fundamental one metre elevation difference between the models.
On open areas like fields the difference is only 0.13 metres but is up to 4 metres in forest areas.
If all the triangulated images have 1 or 2 metre error in their positioning, the error is visible only if it is in height coordinate.
If the position of one image has an error of 1 or 2 metres it causes a deformation in the surface model.
Deformations smaller than two metres in size are not visible however because of large random errors.
Nevertheless, the method does not require large amounts of active working time to compute so it has potential in aerial triangulation quality assurance if the systematic error between the data sets can be decreased.
Abstract (fin):Ilmakolmioinnissa ratkaistaan kartoituksen ilmakuvablokin kuvien sijainti- ja asentotiedot eli orientoinnit.
Orientointeihin mahdollisesti tasoituslaskun jälkeen jäävää virhettä tutkittiin vertaamalla ilmakuvista tehtyä fotogrammetrista pintamallia ja laserkeilausaineistosta tehtyä pintamallia.
Kirjallisuusosa käsitteli näiden pintamallien teoriaa ja tutki erilaisia algoritmeja.
Useita menetelmiä pintamallien muodostamiseen ja erotuksen laskemiseen kokeiltiin mutta näiden välillä on lähtökohtaisesti yli metrin systemaattinen ero.
Avoimilla alueilla ero on keskimäärin vain 0.13 m mutta metsäisillä alueilla jopa 4 metriä.
Kun kaikkien ilmakuvien sijainnissa on 1 tai 2 m samansuuntainen virhe, ero näkyy pintamalleissa vain, jos virhe on korkeussuunnassa, jolloin se siirtyy suoraan mallien erotukseen.
Jos vain yhden kuvan sijaintia poikkeutetaan mihin tahansa suuntaan, se aiheuttaa vääristymän pintamalliin.
Alle kahden metrin vääristymät eivät kuitenkaan ole vielä näkyviä.
Menetelmä ei vaadi kohtuuttomasti aktiivista työaikaa, joten sillä on kuitenkin potentiaalia ilmakuvauksen laadunvalvonnassa, jos mallien välistä systemaattista eroa voidaan vähentää.
ED:2014-08-03
INSSI record number: 49495
+ add basket
« previous | next »
INSSI