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Optimering av datainsamling med UAS : En studie i alternativa flyghöjder kontra mätosäkerheter utförd i AvestaHägglund, Sandra, Lindh, Rose-Marie January 2019 (has links)
Studiens syfte var att genom UAS-fotogrammetri se om det var möjligt att uppnå en mätosäkerhet på 2–3 cm samt se om det är möjligt att använda sprayfärgade kryss som markstöd istället för masonitplattor med målade timglas och ändå uppnå samma mätosäkerhet. Detta gjordes från två olika flyghöjder, 80 m och 110 m för att få en till dimension på studien. Markstöden mättes in med GNSS och i studien användes UAS DJI Phantom 4 v2.0 vid flygfotograferingen. I plan kontrollerades kartan genom detaljmätning med hjälp av multistation etablerad med 180-sekunders metoden. Kontroll av kartan i höjd gjordes genom inmätning av kontrollprofiler med GNSS och multistation. Totalt bearbetades data från 4 inmätningar, data från 80 m där markstöd bestått av masonitplattor respektive sprayfärgade kryss och det samma från 110 m. Databearbetningen utfördes i Agisoft PhotoScan där bilderna bearbetades till en ortofotomosaik, DEM och DSM. Ortofotomosaiken och DEM importerades sedan till ArcMap för skapande av baskarta och för kontroll av koordinaterna i plan. Markmodellen importerades till SBG Geo för vidare bearbetning och kontroll av avvikelse mellan kontrollprofilerna och DEM. Resultatet av 42 st detaljmätningar gjordes genom beräkning av RMS-värdet mellan inmätta koordinater och motsvarande punkt i kartan. Vid flygfotografering från 80 m visade timglas ett RMS-värde på 0,038 m och kryss ett RMS-värde på 0,039 m. Motsvarande från 110 m visar att timglas gav ett RMS-värde på 0,062 m och kryss på 0,048 m. Alla inmätningar utom timglas från 110 m klarar toleransen mot HMK – Geodatakvalitet som är 5 cm och när enbart marknära objekt mättes gav det ett RMS-värde i plan på 0,026 m för timglas från 80 m och 0,023 m för kryss. 2–3 cm mätosäkerhet uppnåddes därmed. Från 110 m blev värdet 0,054 m med timglas och 0,035 m med kryss. Kontroll av höjdosäkerhet gjordes enligt SIS-TS 21144:2016, där 12 kontrollprofiler mättes in och jämfördes mot DEM. Resultatet från 80 m med timglas som markstöd visade en total medelavvikelse på 0,006 m med 0,019 m i standardosäkerhet. Från samma flyghöjd, men med inmätningar av kryss visade ett resultat om -0,001 m med standardosäkerhet 0,030 m. Från den högre flyghöjden med timglas genererades en total medelavvikelse på 0,010 m med standardosäkerhet 0,033 m. Motsvarande genererade kryss en total medelavvikelse på 0,026 m med standardosäkerhet 0,040. Alla 4 markmodellerna klarar den efterfrågade mätosäkerheten om 2–3 cm. / The aim of this study was to collect data through UAS photogrammetry and investigate if it was possible to achieve an uncertainty of 2-3 cm. The second aim was to investigate if it was possible to use spray-colored crosses as control points (GCP) instead of hourglass-painted fibreboards to achieve the same uncertainty. This was done from two different flight heights, 80 m and 110 m to add another dimension to the investigation. The GCPs were measured with GNSS and in the study a UAS DJI Phantom 4 v2.0 was used for aerial photography. The plane coordinates was checked by measuring details using multistation established with the 180-second method. Height control was done by measuring profiles with GNSS and multistation. All together data from 4 measurements were processed; from 80 m where GCPs consisted of hourglass and crosses, respectively, and the same from 110 m. The processing was performed in Agisoft PhotoScan where the images were aligned to an orthophoto mosaic. A DEM and DSM were also created. The orthophoto mosaic and DEM were used in ArcMap for digitizing a base map and for checking the plane coordinates. The DEM was imported to SBG Geo for further processing and control of deviation between profiles and DEM. The result of the 42 measured details was made by calculating the RMSE value between the measured plane coordinates and the corresponding points in the map. In aerial photography from 80 m, hourglass showed an RMSE value of 0.038 m and crosses an RMSE value of 0.039 m. Corresponding from 110 m, hourglass gave an RMSE value of 0.062 m and a cross of 0.048 m. All measurements except hourglass from 110 m can withstand the tolerance to HMK – Geodatakvalitet (2017) which is 5 cm. If only ground-level objects were to be measured the RMSE value of 0.026 m for hourglass from 80 m and 0.023 m for crosses reached the wanted measurement uncertainties of 2–3 cm. From 110 m the value was 0.054 m with hourglass and 0.035 m with cross. The control of the height uncertainty was made in accordance with SIS-TS 21144:2016, where 12 profiles were measured and compared with the DEM. The result from 80 m with hourglass showed a total mean deviation (MD) of 0.006 m with 0.019 m in standard deviation (SD). From the same flight height, but with crosses, a result of -0.001 m with SD showed 0.030 m. From the higher height with hourglass, a total MD of 0.010 m with SD 0.033 m was generated. The corresponding crosses got a MD of 0,026 m and a SD of 0,040 m. All 4 DEM can handle the required measurement uncertainty of 2-3 cm.
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Custom Base Maps for Utility Network Applications / Anpassade Baskartor för Allmänyttiga NätverksapplikationerEduards, Rasmus January 2019 (has links)
Web maps are today used more than ever. These are often displayed in geographical information system solutions. Web maps are often constructed in the terms of different layers where the bottom-most layer is called base map or background map. A specific kind of base maps are those that are the canvas for utility networks. These base maps can look vastly different from each other. Sometimes the base map can be overlooked. Currently there are different theories and opinions on how these base maps shall be designed and what information they shall contain. This thesis investigates a suitable base map design for utility network management and also creates some prototypes as a proof of concept. The thesis focus mostly on three factors, colour, information visualisation and symbology. This is investigated by using a user-centred design approach and comparing it to existing findings in literature and among map theories. The user-centred design process involves a case study performed with participants that work with utility networks in web map solutions. The research method is an iterative process where the participants are answering three quantitative surveys. The surveys includes prototypes which is refined for each step after analysing the participants answers. The thesis concludes that low saturated colours is good practise to enhance the network, this is both evident in literature as well as in the case study. Amount of lightness in the base map seem to be more of a opinionated matter and can highly differentiate depending on users device. Using hue is recommended to make borders between map elements more distinct. The base map shall only obtain the most relevant information and more specific information is recommended to be added through additional layers. Further studies need to be done in order to investigate the networks design and there is also a need to investigate how a map solution with several layers shall be design and how the relationships between those layers shall be constructed for utility network management
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