Dissertations / Theses on the topic 'LASERSKANNING'
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Rönnbäck, Sara, and Anna Johansson. "Bilburen laserskanning." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-25654.
Full textRydberg, Erik, and Andreas Johannesson. "Laserskanning av Södra Climate Arena." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-56461.
Full textKadric, Zuhret, and Örjan Forsmark. "Terrester laserskanning för inmätning av spåranläggningar." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-8306.
Full textThe railways are nowadays congested with traffic and are sensitive to disturbance. Rail infrastructure works are something that must be carefully planned and executed when it involves as little disruption as possible for rail traffic. In addition safety of all activities related to railway environment should be considered. All work within the track area must therefore meet certain requirements. This may also influence detail measurements within the track areas where the track must be closed. An alternative is to use a terrestrial laser scanner that can be placed outside the track area, which could be a more flexible way to measure the centre line of the track. The aim of this study is to show how measurements with terrestrial laser scanning (TLS) can be performed in track environment, compare them to traditional measurements with total station and determine whether the Swedish Transport Administrations tolerance requirements can be achieved with TLS measurements.The section of the railway that was surveyed was about 100 m long. Track surveying was carried out with total station with an interval of 1-2 m. In total, 85 points on the track centre line were measured, which could then be compared with laser scanning measurements. The measurements with laser scanner were made from five different set ups at the distance of about 10 m at orthogonally to the nearest rail. The results of comparison of the line data from the two measurements shows a mean radial difference in a horizontal plane of 3 mm. and difference in height shows a mean of 5 mm. To demonstrate how to identify different objects in point clouds, a range of images are presented, which in an easily comprehensible format showing how much information is available in the form of points. For a vehicle, to be able to travel on rail track, must meet the requirements for so called loading-gauges. In the point clouds, a load profile was created with a few simple commands. Then it can be moved along the track center line and set in relation to all surrounding objects. In our work, TLS has proved to have great potential for determination of the track center line and detail measurements within the track area. During the relatively short time, large amounts of data in the form of point clouds were generated from which individual items could be easily distinguished. Surveying work on a busy railway is surrounded by restrictions, but TLS measurements, which can be carried out outside the security zone, require only the presence of an instrument operator. The major safety requirements that should be adhered to in surveys of track areas are satisfied completely, since no surveying staff should work in the security zone during TLS measurements. Conclusions that can be drawn from our study are that accuracy in measuring the track center line with TLS is comparable to the measurement with the total station. The quality of the measurements meets the requirements for the measurement with total station of Swedish Transport Administrations. Thanks to the rapid collection of large amounts of data TLS can contribute much in the surveys of railway areas where the concentration of objects is large. Data can be saved and any missed checks can be performed trough extraction of necessary data from the point clouds without the need for new measurements. This may also facilitate future work with the planning and design when information about a track environment is needed.
Ågren, Ulrika. "Laserskanning som metod för byggnadsarkeologisk visualisering." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-15935.
Full textColfach, Peder. "3D Laserskanning : Verktyg för antikvarisk dokumentation." Thesis, Uppsala universitet, Kulturvård, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-326304.
Full textThis study aims to figure out if there is any heritage aspect when documenting heritage buildings with 3D laser scanning in Sweden. The paper is based on three case studies of two privately owned and one public building where the purpose for 3D scanning has had different goals. In simple words this paper aims to describe what laser scanning is and how you work with the laser scanning in the field. Through comparing results from prior studies on the matter, this study also aims to describe the advantages that come from using 3D laser scanning on heritage buildings. This study finally wants to bring up the subject and discuss the terms and uses of fulfilling a building heritage documentation that suites our time.
Pramlid, Björn. "Tillämpning av kinematisk terrester laserskanning i järnvägsmiljö." Thesis, University of Gävle, Ämnesavdelningen för samhällsbyggnad, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-4868.
Full textLarsson, Oskar, and Jacob Hallberg. "Vägmodellering baserad på laserskanning för virtuella fordonssimuleringar." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-88965.
Full textProduct development is necessary to compete in today´s vehicle industry. During the design process the largest possibility to affect the end product to the better exists. One way to achieve product development is to apply new technology. Through application of terrestrial laser scanning digitalized road models can be achieved and be used in simulations. In these simulations, vehicles can virtually do a trial run and thereby shorten the dimensionprocess. Laser scanning of hilly terrain is complex and therefore groundwork of hilly roadways in simulations is missing. This study refers to present different types of laser scanning methods and expand the groundwork for virtual simulations in the dimensionprocess of dumpers. The vision is to create virtual roadways which can be used in simulation models. Three main techniques of laser scanning are presented in the theory chapter. Further on terrestrial laser scanning has been used on Volvos test track in Målajord and with this scanning data as groundwork a road model, which can be used in vehicle simulations, has been created in Matlab. The road model is well representing the real roadway, which indicates that terrestrial laser scanning is a well working method for this purpose.
Nilsson, Erik, and Erik Vestin. "Prediktion av skogliga variabler med flygburen laserskanning." Thesis, Umeå universitet, Statistik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-122692.
Full textLundström, Fredrik. "Utvärdering av miljön i området Torparängen med laserskanning." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-61967.
Full textSkalin, Malcolm. "Undersökning av georefererings- och skanningsmetoder för handburen laserskanning." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-21536.
Full textThe purpose of this thesis work is to investigate methods for georeferencing and scanningwith the handheld laser scanner ZEB1 and state recommendations if the scanner can beused within a certain demand in uncertainty and which methods are most suitable forthese kinds of tasks. The scanner ZEB1 was borrowed from Sweco AB in Gävle toperform the study. Three different methods of scanning was used, simple scanning werethe area were scanned once, double scanning were the area were scanned twice and “Stopand Go” were the scanner was used around the signals over a period of time. All the scanswere georeferenced with two different techniques, spheres and natural points. Asecondary purpose is to evaluate how easy the point clouds can be processed and todetermine which method is most suited for the task. The scans were done February 2014in house 45 by the University of Gävle. The coordinates for the sphere and natural points where measured with a total stationLeica Viva TS15 whose coordinates had been determined in the local reference system.The scans were performed and georeferenced with the spheres and natural points in thesoftware Cyclone 7.4. The results for georeferencing had an RMS value of threecentimeters for all the point clouds. The method “Stop and Go” delivered a moremanageable point cloud which illustrated the best point density around signals. Doublescanning produced the worst because the amount of noise in the cloud was moreextensive. A combination of georeferencing with sphere and natural points were done butgave no better results. ZEB1 should not be used for precision scanning because most ofthe results get a 3 - 5 cm value for georeferencing and coordinate difference between theknown natural points and the scanned ones were around 3 - 7 cm.
Jansson, Tom. "Utvärdering av terrester laserskanning i framställandet av en 3D-modell : Baserat på underlag från ritning och terrester laserskanning av en fackverksbro." Thesis, Högskolan Dalarna, Byggteknik, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:du-27852.
Full textIn recent years, the implementation of building information modeling (BIM) in the Swedish civil engineering industry has increased. This is due to directives from the government stating that the Swedish Transport Administration (Trafikverket), in greater occurrence, will benefit from the digital possibilities with the BIM concept. Trafikverket is the government agency responsible for the long-term planning and management of public roads, construction in the infrastructure such as tunnels and bridges, and has great influence in the Swedish civil engineering industry. They claim that the key to enhance the use and development of BIM is to raise their demands towards the rest of the industry. Transitioning from a drawing-based to an object-based approach will affect the entire industry. The idea is to be able to handle all the information in 3D-data and the BIM concept throughout the entire life cycle of the construction. To reach that ambition, the already-built constructions need to be represented as 3D-models in terms of being a part of the BIM concept. Terrestrial laser scanning is a method of measurement that is being used worldwide for 3D-documentation of complex objects and environments. The result of a scan is comprehensive with low uncertainty of measurement; therefore the method is well suited to assist in the creation of 3D-models. The primary aim of the study is to examine the differences between 3D-models, depending on the measurement method that was used to create them. An analysis of the current situation in these fields-of-study was made by a literature study to place this thesis in its proper context. Although the two 3D-models were the same exact object, they were created using two different methods of measurement. The models were compared to identify the differences between them. The study unveils that the choice of measurement method influences the results of the 3D-model, where the terrestrial laser scanning method could help to improve the quality of the final product. On the other hand, there were areas where the two methods of measurement could complement each other for even better results.
Neiß, (Neiss) Michael. "Birka är ingen ö : om båtgravar, barockspännen och laserskanning." Uppsala universitet, Institutionen för arkeologi och antik historia, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-180571.
Full textÖvriga forskningsfinansiärer:
Berit Wallenbergs stiftelse ("Transformationer inom vikingatidens djurornamentik"), Helge Ax:son Jonsons stiftelse ("3D-laserskanning som verktyg vid vikingatidsstudier")
En förlorad värld? - Turinge re-visited
3D-laserskanning som verktyg vid vikingatidsstudier
Transformationer inom vikingatidens djurornamentik
Nordström, Daniel. "Positionering av markörer för luftrörelser : handhållen längdmätare kontra laserskanning." Thesis, University of Gävle, Department of Technology and Built Environment, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-770.
Full textLuftens tillstånd (t.ex. temperatur och fuktighet) och rörelser i större lokaler kan mätas med hjälp av ett klimatmätsystem. För att luftens temperatur och fuktighet samt hastighet och riktning ska kunna simuleras i 3D måste sensorerna i klimatmätsystemet positioneras. I denna studie har två metoder som kan användas för positionering av objekt jämförts och utvärderats. En ena är enkel i sitt utförande och använder sig av en handhållen längdmätare. Objekts position beräknas genom triangulering av tre mätta längder till punkter med kända koordinater. Den andra metoden använder en terrester laserskanner och resultatet från den metoden kommer att anses som korrekt och utgöra studiens referens.
Syftet med studien är att undersöka om det med den enkla metoden går att uppnå centimeternoggrannhet vid positionering av objekt samt vilken markörstorlek som är lämplig att använda. Studien ska även innefatta utvecklingen av den mjukvara för att hantera mätdata och utföra positionsberäkningarna för en enkla metoden.
Fem kända punkterna mättes in med en Leica TPS1200 totalstation. 16 klotformade markörer med diameter från 20 till 50 mm monterades i 4 markörgrupper på stativ placerades ut i lokalen. Markörerna skannades med en Leica HDS3000 laserskanner och markörernas punktmoln modellerades för att erhålla deras positioner. Samtliga markörer mättes därefter in från de kända punkterna med en längdmätare Leica Disto Plus. Avstånden från de kända punkterna till respektive markör sparades i programvaran DistoPos som när längdmätningarna var gjorda även beräknade markörernas positioner.
De båda metodernas resultat jämfördes, genom att beräkna den enkla metodens radiella noggrannhet, med resultatet från laserskanningen som referens. Den bästa noggrannheten uppnåddes när den enkla metodens positioner beräknades med avseende på avståndet till de kända punktera. När de tre kortaste avstånden användes för positionsberäkningen halverades onoggrannheten. Detta beror främst på att geometrin hos de i beräkningen ingående kända punkterna förändrats till det bättre. Detta understryker vikten av god geometri hos de kända punkterna som ligger till grund för positionsberäkningarna. Resultatet visar att det kommer att bli svårt att uppnå centimeternoggrannhet med metodens förutsättningar.
Markörernas diameter bör väljas till mellan 30 och 40 mm. Positionsberäkningarna för den enkla metoden skulle kunna förbättras ytterligare genom att inkludera någon typ av utjämning samt rutiner för att hitta och korrigera för grova fel.
The state of air (temperature and humidity) and movements in larger premises can be measured by a climate measuring system. In order to simulate air humidity, temperature, speed and direction in 3D the sensors in the climate measuring system needs to be positioned. In this study, two methods that can be used for positioning of objects are compared and evaluated. The first one is simple and uses a hand-held distance meter. The objects position are calculated by triangulation of three measured distances to points with known coordinates. The second method uses a terrestrial laser scanner and the result of this method will be considered as correct and constitute the study reference.
The purpose of the study is to examine whether it with the simple method is possible to achieve centimetre accuracy when positioning objects and determine what marker size that is appropriate to use. The study should also include the development of a software to manage measured data and perform the position calculations for the simple method.
Five known points were surveyed with a Leica TPS1200 total station. 16 spherical markers with the diameters from 20 to 50 mm were assembled in 4 marker groups and placed on stands. These markers were scanned with a Leica HDS3000 laser scanner and markers point cloud was model to obtain positions. All markers were then surveyed from the known points with a distance meter Leica Disto Plus. The distances from the known points to each marker were stored in the software DistoPos where the makers positions also were calculated.
The two methods result were compared by calculating the simple method radial accuracy with the results of the laser scanning as a reference. The best accuracy was reached when the simple method positions were calculated in terms of the distance to the known points. When the three shortest distances were used for positioning the unaccuracy was divide into halves. This is mainly because of the geometry of the known points included in calculations was changed to the better. This underlines the importance of good geometry of the known points included in the calculations. The accuracy of individual markers ranged between 3 and 36 mm. The result shows that it will be difficult to achieve centimetre accuracy with the methods prerequisites.
The position calculations for the simple method would be further enhanced by the inclusion of some kind of adjustment, and procedures to identify and correct gross errors.
Wiberg, Frida, and Agnes Rindberg. "Laserskanning och 3Dmodellering för rekonstruktion av ett medeltida kyrkorum." Thesis, Linnéuniversitetet, Institutionen för byggteknik (BY), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-89788.
Full textThis study is describing a 3D reconstruction of a medieval church located 25 kilometers south of Växjö. The church is very special as the appearance of the building is still very original. The church also has an unusual roof construction that this project wants to point out. However, the roof structure once visible from the church room, is today hidden by a ceiling which was erected later in an indefinite time. The purpose and goal with the 3D reconstruction is to recreate the original church hall and compare it with the contemporary interior design based on three aspects; experiences of light, - the room in general and the experiences of movement patterns in the church. The result of the project showed that the church hall earlier on was much darker inside due to the lack of windows, but the church hall was on the other hand very spacious in the middle ages because the interior was not furnished during this time. Today the church has received more and larger windows and the hall is furnished with pews and a pulpit, which have led the movement pattern to an aisle from west to east in the middle of the church hall. In future projects, about churches and older constructions, this study can be used as guideline and support for further studies. It is also a study that is open for additional development, as for example the 3D reconstruction can be translated into VRtechnology, so that people can experience the medieval church as it was in the 13th century, almost like they were there.
Al-yousifi, Yani, and Mustafa Deniz. "EN JÄMFÖRELSESTUDIE MELLAN MANUELL UPPMÄTNING OCH LASERSKANNING VID OMBYGGNATION." Thesis, Tekniska Högskolan, JTH, Byggnadsteknik och belysningsvetenskap, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-51082.
Full textSyfte: I en undersökning från Boverket i Sverige har man inom byggnadsbranschen kartlagt viktiga orsaker för brister, fel och skador vid bland annat ombyggnationer. Tidsbrist visade sig vara den största orsaken som även medför stora åtgärdskostnader för avhjälpande av fel/skador. Digitala verktyg medför möjligheter för effektivisering av tidsåtgång samt kostnader. Laserskanning är ett sådant verktyg med likadana möjligheter. Kunskapen om laserskanning är emellertid inte omfattande inom byggnadsbranschen och/eller så antar man att det kostar mycket. Målet med arbetet var att jämföra laserskanning gentemot manuell (traditionell) uppmätning för att veta vilken metod som är mer fördelaktig med avseende på olika faktorer ur ett lönsamhetsperspektiv. Metod: För att uppnå arbetets mål användes en undersökningsstrategi som var både kvalitativ samt kvantitativ. Med litteraturstudie och intervjuer samlades kunskap om fördelar/nackdelar för de båda uppmätningsmetoderna (laserskanning och manuell uppmätning) samt faktorer som påverkar lönsamheten vid användning utav dessa. Beräkningar genomfördes för att jämföra kostnader för metoderna beträffande projektets komplexitet. Resultat: Det genererade resultatet visar att laserskanning har fler fördelar än manuell uppmätning. Laserskanning tar mindre tid att utföra vid större projekt och medför en större noggrannhet på relationshandlingar än manuell uppmätning bland annat. Ur ett kostnadsmässigt lönsamhetsperspektiv är det viktigt att för varje specifikt projekt göra egna beräkningar för att se vilken uppmätningsmetod som blir billigast. Det projektet som användes i detta arbete hade varit mer lönsam med laserskanning som uppmätningsmetod, medan det för andra projekt eventuellt kan vara mer lönsamt med manuell uppmätning. Konsekvenser: Studien indikerar på att laserskanning är mer lönsam vad det gäller tid. Laserskanning bör väljas som uppmätningsmetod om man vill spara tid vid större projekt samt få bättre noggrannhet vilket medför mindre fel i projekteringen. Undersökningen ger även beställare och entreprenörer en bättre syn på vilka fördelar man får genom att använda sig av laserskanning. Begränsningar: Undersökningen var begränsad till att endast behandla markbunden laserskanning vid uppmätning av befintliga byggnader inför ombyggnationer, därför kan inte resultatet generaliseras till andra typer utav laserskanning. Nyckelord: Laserskanning, Manuell uppmätning, BIM, Lönsamhet, Ombyggnation, Komplexitet, LOD.
Ohrzén, Susanna, and My Westlund. "Möjligheten att använda terrester laserskanning och fotobaserad skanning vid utredning av trafikolyckor." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-20196.
Full textMurmester, Patrik, and Tobias Thor. "Utvärdering av programvaror för automatisk 3D-modellering från terrestra laserdata i industrimiljöer." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-11968.
Full textIt is important that plants and other industrial environments are mapped correctly, in order to maintain knowledge of the positions of machines and other equipment. Three-dimensional models provide simple and clear information about a plant's structure. Traditional methods, such as measuring tape or a total station are both relatively slow and it can be difficult to achieve the required precision. Terrestrial laser scanning (TLS) is an increasingly common method for creating 3D models of industrial environments and the technology has developed rapidly in recent years. The modeling process begins with segmentation, a classification of all points in a point cloud. After that, 3D models are created, which generates a simplified view of reality, which can be obtained by using various methods. Modeling is today a very time-consuming task due to the large amount of manual interpretation is required, In order to increase efficiency, the process needs to be more automated. The purpose of this study is to evaluate software´s for 3D modeling of data based on TLS, with special emphasis on automatic features. Two software´s have been evaluated: Edge Wise Plant 3.0 and AVEVA Laser Modeller, with respect to e.g. quality of the model, which objects can be modeled, time consumption and application handiness. Also Cyclone 7.3 is included in the study, as a representative of software mostly focused on manual modeling. For the evaluation, point clouds from a steel mill are used, mostly consisting of pipes and elbow connections, but also other items commonly used for industrial environments. In addition to this, point clouds over a number of cylindrical objects with known diameter were created. These scans were done with different point densities. The results show that the software´s is quite different, but they all work well for modeling the industrial environments. They have different strengths and weaknesses, and therefore the best software suited for modeling of industrial environments is dependent of the needs. Fully automatic modeling of piping systems has great potential, and the time consumption significantly reduces. There is still a lot of technology development needed in order to achieve the required quality of the model. Modeling with more manual processing is more time consuming, but in return the model may be more accurate, and the user has more control of achieving satisfactory results.
Persson, Mattias. "Terrester laserskanning eller totalstation : – en jämförelse vid inmätning i stadsmiljö." Thesis, Karlstad University, Faculty of Social and Life Sciences, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-1819.
Full textDen nya mätningstekniken på marknaden kallas terrester laserskanning. Tekniken bygger på att ett instrument, monterat på ett stativ, sänder ut en laserstråle vilken avlänkas i vertikalled av en spegel samtidigt som det roterar. Laserstrålen reflekteras mot de objekt som befinner sig inom laserskannerns synfält och resulterar i ett punktmoln. Punktmolnet innehåller ofta flera miljoner punkter vilka alla erhåller xyz-koordinater. Tekniken har visat sig lämplig vid dokumentation av byggnader och vid modellering samt kartläggning av industrier och tunnelbyggen.
Denna studie har genomförts på Sweco VBB i Karlstad i syfte att ta reda på hur lämplig terrester laserskanning är vid vardaglig inmätning och kartering av objekt i stadsmiljö. Metoden har jämförts med traditionell inmätning med totalstation utifrån ett antal frågeställningar. I studien laserskannades två korsningar i Vasastaden, Stockholm. Instrumentet som användes var en IMAGER 5006 av märket Zoller+Fröhlich. De totalt sex stycken skanningarna resulterade i punktmoln vilka georefererades genom att måltavlor mättes in med totalstation. Efterbearbetningen bestod av registrering, redigering och reducering av punktmolnen. Genom manuell tolkning av punktmolnen och med hjälp av verktyget Virtual Surveyor i Leica Geosystems programvara Cyclone, kunde olika objekt mätas in och kartläggning av de båda korsningarna ske.
En generell jämförelse mellan terrester laserskanning och totalstation visar att laserskanning är en snabb metod som ger stora mängder data med hög detaljrikedom, medger en större säkerhet i fält och ger enorma möjligheter för visualisering, modellering och skapande av terrängmodeller. Laserskanning är dock en dyr metod som ger en något sämre noggrannhet och som ännu inte klarar att mäta sträckor över hundra meter. Metoden kräver också totalstation (eller GPS) för georeferering. Studien har också visat att tidsvinsten som uppkommer i fält förloras genom tidsödande efterbearbetning och manuell tolkning av punktmolnet. Trots detta använder idag ett flertal företag denna metod vid inmätning. Slutsatserna pekar främst på att laserskanning som inmätningsmetod lämpar sig bäst över små områden där antalet objekt är högt och där säkerheten i fält är viktig. Dock ses metoden mer som ett komplement till totalstationen genom de möjligheter som erbjuds via visualisering och modellering och därmed inte en ersättare för den senare.
A new technique for surveying is the terrestrial laser scanning. The technique is based on an instrument, mounted on a tripod, emitting a laser pulse which is vertically deflected by a mirror while rotating. The laser pulse is reflected by the objects within the field of view of the laser scanner. The laser scan results in a point cloud most often containing several millions of points which all have XYZ-coordinates. The technique has proven its benefits when documenting buildings, modelling and surveying of industries and tunnels.
This study has been carried out at Sweco VBB in Karlstad in purpose of finding out how suitable terrestrial laser scanning is for everyday surveying in urban environment. The method has been compared with traditional surveying with total station from a number of questions. In the study two crossings in Vasastaden, Stockholm, were scanned. The instrument used was an IMAGER 5006 from Zoller+Fröhlich. The 6 scannings resulted in point clouds which were georeferenced by using targets and a total station. The post processing consisted of registering, editing and reducing the point clouds. Through manual interpretation of the point clouds and by using the tool Virtual Surveyor in the program Cyclone by Leica Geosystems it was possible to survey different objects at the crossings.
A general comparison between terrestrial laser scanning and total station shows that laser scanning is a rapid method producing large amounts of data with a high level of details, allows higher security in field and gives enormous possibilities for visualisation, modelling and creating of terrain models. However, laser scanning is an expensive method which gives a slightly lower accuracy and yet cannot be used for longer distances. The method also demands total station (or GPS) for georeferencing. The study has also shown that the saving of time in field is lost by time consuming post processing and manual interpretation of the point cloud. Nonetheless this method is used by several companies for everyday surveying. The conclusions advert mostly that laser scanning is best suitable for small areas where the number of objects is high and where security in field is important. Nevertheless, the method should be seen more as a compliment to the total station because of the possibilities offered by visualisation and modelling and therefore not as a replacement for the latter.
Hjelmér, Minna. "Skattning av antal träd baserat på data från flygburen laserskanning." Thesis, Umeå University, Mathematics and Mathematical Statistics, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-31711.
Full textFör att skatta skogsegenskaper utifrån data baserade på flygburen laserskanning används framförallt två olika metoder. Den första (areametoden) bygger uteslutande på höjden där laserpulserna reflekterats och en uppskattning av vilka pulser som reflekterats på marken och vilka som reflekterats i vegetationen. Den andra metoden (segmentmetoden) använder en segmentering av punkterna där laserpulserna reflekterats till enskilda träd. Detta är dock svårt att praktiskt genomföra, därför innehåller varje segment mellan 0 och cirka 10 träd. För att kunna utveckla och utvärdera resultaten insamlas även exakt information från ett antal provytor genom fältstudier. I denna rapport föreslås en icke-parametrisk modell för att skatta antalet träd i ett segment med segmentens area och art som förklarande variabler. Modellen skattas med hjälp av alla segment som finns inom en provyta, även de som inte helt ligger inom provytan. Modellen valideras på tre olika sätt och det visar sig att antalet träd i princip skattas väntevärdesriktigt. Dessutom förbättras inte resultatet nämnvärt med trädart som förklarande variabel.
To estimate forest characteristics based on airborne laser scanning data, two methods are used. The first one is on a raster cell level and uses solely the height of where the laser pulse is reflected and whether it is reflected on the ground or not. The second one is on an individual tree level and uses segmentation of the reflection points into individual trees. However, since it is difficult to segment into individual trees, every segment contains between 0 and about 10 trees. To be able to develop and validate the results, exact information about the trees in different field plots is gathered. In this report a nonparametric model is suggested to predict the number of trees in a segment, with area and species of the segments as predictors. In the estimation of the model, all segments within the field plots are used, even those only partly within. The model is validated in three different ways and estimates the number of trees with very small bias. Also the predictor, species of the segments, does not improve the results much.
Dalheimer, Jan. "Transformation av geodetiska höjdnät med flygburen laserskanning : En inledande genomförbarhetsstudie." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27775.
Full textWhen the requirements on accuracy and precision are high for geodetic measurements you need geodetic reference systems realized with geodetic control networks of high quality. Today, establishment and transformation to higher order reference systems for height usually uses terrestrial methods like levelling. While highly accurate these result in time consuming work. There have been a couple attempts at using other methods for this task, for example GNSS, but another possibility might be usage of point clouds from airborne laser scanning. As a starting point for further studies this study attempts to use point clouds to transform a geodetic height network in Sandviken municipality, Sweden. The network consists of around 500 benchmarks and has been transformed to the national reference system for height, RH2000, by the Swedish national geodetic survey (Lantmäteriet) in 2010. The point cloud used is also produced by Lantmäteriet and is said to have a mean error of 0,05 m. This is relatively high since the requirements usually are in the millimeter range when determining transformation parameters, but if the transformation only consist of a single height shift calculated as a mean from several height shifts derived from the point cloud any random errors in the point cloud should be reduced. By measuring the height difference between benchmarks and points on the ground, that through different methods are given heights according to the point cloud, heights of the benchmarks have been determined according according to the point cloud. These can be compared to heights in RH2000 according to the transformation performed by Lantmäteriet to see their deviation from the assumed true value. Further comparisons against the older local heights of the benchmarks give a height shift that can be used as a simple transformation. By calculating a mean and uncertainty an estimation of the suitability of the method can be achieved. The all height shifts deviated a few millimeters from the result Lantmäteriet got, with uncertainties around 3 mm for the overall best method. Even if the uncertainty of the shift and therefore the transformation ended up somewhat high compared to what Lantmäteriet achieved it is still believed that point clouds may be or become a viable alternative. Especially in more remote regions without good connections to the higher order network. There are many parameters that have not yet been explored though, as well as some potential systematic errors that should be further investigated.
Hermansson, Niklas, and Andreas Berg. "Infallsvinkelns påverkan på mätresultatet vid terrester laserskanning : undersökning av ScanStation 2." Thesis, University of Gävle, Ämnesavdelningen för samhällsbyggnad, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-4748.
Full textNoggrannheten hos mätningar gjorda med en terrester laserskanner påverkas av många faktorer. En viktig faktor som bör undersökas är laserstrålens infallsvinkel. Vårt syfte med den här undersökningen var att kontrollera laserskanner Leica ScanStation 2 vad gäller infallsvinkelns påverkan på punktmolnets noggrannhet. Undersökningen bestod av skanningar från 10-100 m avstånd mot en specialbyggd kub på 1x1x1 m, med infallsvinklar 0-85°, både inomhus och utomhus. Efterarbetet gjordes i programvaran Leica Cyclone där vi registrerade och modellerade våra punktmoln till olika plan. Resultaten visade en tendens att med ökad infallsvinkel till den inskannade kubens yta ändras resultatet av plananpassningen, vilket betyder att ett fel i avstånd uppstått. De slutsatser vi tagit var att det på 10-20 m avstånd uppvisades så små variationer i planinpassningen att infallsvinkels påverkan på precisionen av inpassade plan ligger inom förväntad noggrannhet och kan förbises. Vi såg en liknande trend för längre avstånd, 30-100 m, men felet var större än det förväntade samt att det visade på en viss instabilitet och infallsvinkeln måste tas i beaktning. Extrema infallsvinklar på 80-85° bör undvikas eftersom mätningarna där blir allt för ostabila.
Eriksson, Martin, and Karl Grönlund. "Jämförelse av programvaror för konstruktion i råa punktmoln." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-183527.
Full textEricson, Johanna. "Nyttan av en höjdmodell för Örebro kommun." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-8602.
Full textIn the municipality of Örebro the elevation model provided by the National Land Survey is used. This elevation model offers an accuracy of around 2 m. In the city of Örebro, height information is also available in the form of contours with an equidistance of 1 m. Along with progress, uses for a new, improved elevation model are seen. In order to produce such an elevation model it is necessary to collect large amounts of data. The method best suited for data collection of this extent is airborne laser scanning. Laser scanning is a relatively new method that is based on the fact that distances to objects can be calculated with the aid of emitted laser beams. The method allows information about the position of tens of thousands of points to be collected per second. This makes airborne laser scanning a very time efficient method. The National Land Survey is planning on collecting data over the whole of Sweden using airborne laser scanning. This will be done in order to produce a new, improved elevation model. In the municipality of Örebro the alternative of conducting an own scan of the municipality is being examined. The purpose of this report is to examine the benefits for the municipality of producing an elevation model that offers better accuracy than the one available today. The report is based on literature studies and interviews. Members of staff at the municipality of Örebro have been interviewed in order to find out what different uses they can see for a new elevation model. Interviews with staff at Stockholms Stad and Borås Stad have been carried out in order to find out some of the benefits they have had with their respective elevation models and also learn of their experiences. From the result the following conclusions are drawn: An elevation model over the municipality of Örebro will be useful for flood prediction models and urban planning; In order for the elevation model to be of as much use as possible, and also be useful for future projects, an accuracy of 10 cm is recommended; The option of waiting for the National Land Survey’s new elevation model should be investigated further, also taking economic aspects into account.
Lundmark, Johan, and Häggström Lukas Grönlund. "Utvärdering av digitala terrängmodeller framtagna med flygburen laserskanning och UAS-fotogrammetri." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-27295.
Full textDe senaste åren har tekniken för Unmanned Aircraft System (UAS) utvecklats snabbt och idag finns flera system på marknaden. Ett resultat av den snabba utvecklingen är att de olika systemen skiljer sig åt, dels i pris men även i kapacitet. Syftet med studien var att undersöka hur olika UAS-system skiljer sig åt i mätosäkerhet vid framställning av digitala terrängmodeller, men även hur olika UAS-system står sig mot det regelverk som finns för framställning av digitala terrängmodeller vid detaljprojektering enligt SIS-TS 21144:2016 Tabell 6 klass 1-3. Ytterligare ett syfte med studien var att undersöka hur olika programvaror skiljer sig åt vid framställning av punktmoln från bilddata. I studien kontrollerades och jämfördes tre digitala terrängmodeller genererade över samma område med två olika UAS-system samt laserskanning från ett flygplan. Terrängmodellerna jämfördes mot kontrollprofiler framställda med RUFRIS-metoden. De olika UAS-systemen var en dyrare variant, Smartplanes S1C (fastavingar), och en billigare variant, Dji Phantom 4 PRO (roterande vingar). De tillämpade flyghöjderna för flygningarna var 174 m för Smartplanes och 80 m för Dji Phantom. Resultatet från studien visar att laserskanning från flygplanet uppnådde lägst mätosäkerhet och klarade samtliga krav för varje separat marktyp för detaljprojektering enligt SIS-TS 201144:2016 Tabell 6 klass 1-3. Marktyper som undersöktes var: asfalt, naturmark, gräs och grus. Vidare klarade terrängmodellen producerad med Dji Phantom endast kravet för asfaltsytor, där medelavvikelsen fastställdes till 0,001 m. Terrängmodellen producerad med Smartplanes klarade endast kraven för marktyperna asfalt och grus där medelavvikelsen fastställdes till -0,007 m respektive 0,017 m. Som en del i studien jämfördes programvarorna PhotoScan och UASMaster för framställning av punktmoln för bilder insamlade med Smartplanes S1C. Resultatet visar att PhotoScan uppnådde lägst mätosäkerhet för asfalt, gräs och grus medan UASMaster uppnådde lägst mätosäkerhet för naturmark. Studien visar att flygburen laserskanning borde vara en fortsatt föredragen metod för insamling av topografisk data då metoden resulterade i lägst mätosäkerheter i denna studie. Vidare visar studien att det är möjligt att framställa digitala terrängmodeller med UAS för detaljprojektering enligt SISTS 21144:2016 för asfalt- och grusytor. Dessutom konstateras att olika bearbetningsprogram skiljer sig vid framställning av punktmoln.
Edholm, Felicia, and Sofie Classon. "Utvärdering av terrester laserskanning som metod vid exteriör dokumentation av Hälsingegårdar." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-24984.
Full textByggnader i trä kan vid ändrade fuktförhållanden påverkas negativt genom bland annat sättningar och deformationer. Hälsingegårdar är ett antal äldre bondgårdar, där sju av dessa är listade på UNESCO:s världsarvslista. Hälsingegårdarnas träbyggnader speglar 1700- och 1800-talens byggnadstekniker i Hälsingland och är därför av värde, både ekonomiskt och kulturellt. För att bevara byggnaderna i deras ursprungliga skick samt för att föra vidare kunskapen kring dåtidens byggnadstekniker krävs en noggrann dokumentation. Noggrann dokumentation är möjlig med hjälp av tredimensionella modeller skapade med exempelvis terrester laserskanning (TLS). Syftet med den här studien har varit att ta fram rekommendationer för utförandet av dokumentation av gamla träbyggnader, till exempel Hälsingegårdar, med hjälp av TLS samt att skapa underlag för framtida deformationsundersökningar på Hälsingegården Slåttagården. TLS utfördes under april månad 2017 på Slåttagården. Med GNSS-mottagare mättes fem punkter in för att etablera ett referensnätverk. Ett antal kontrollpunkter mättes in på byggnaden av huvudintresse med hjälp av en totalstation. Med totalstationen mättes också stödpunkter kring byggnaden in, dessa markerades med sfäriska signaler. Efter sex uppställningar TLS registrerades punktmolnen på två olika sätt; punktmolnsregistrering och registrering baserad på konnektionspunkter. Därefter georefererades punktmolnen till externa referenssystemet. Lägesosäkerheten kontrollerades därefter i programvaran Cyclone genom en jämförelse mellan kontrollpunkter och modellerade plan från det georefererade punktmolnet. Registrerings- och lägesosäkerheter för de båda registreringsmetoderna skiljer sig marginellt åt, vilket talar för att användning av signaler i laserskanningsprojekt liknande denna studie inte är nödvändig. TLS begränsas av att det är en markbunden teknik och behöver därför kompletteras med annan dokumentationsteknik, till exempel obemannade flygfarkostsystem (UAS). I studien skapades ett underlag för framtida deformationsundersökningar på Hälsingegården Slåttagården. Insamlade data har låg lägesosäkerhet (cirka 0,01 m) och bedöms därför ha goda förutsättningar för fortsatta deformationsundersökningar.
Viklander, Mikael. "Undersökning av algoritmer och programvaror för markklassning av punktmoln från flygburen laserskanning." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-10881.
Full textThe Swedish National Land Survey has since 2009 worked on the project “New National Elevation model”, that is a terrain model that will cover the whole area of Sweden, this time using airborne laser scanning for data collection instead of photogrammetry. In order to create terrain models from the laser data, the data need to be processed to separate the ground from other types of objects that the laser scanners laser pulse register. This is one of the main problems for achieving a good quality of the final product (terrain models). Because the country's area is so large, the classification is done by a software, where an algorithm tries to filter out the ground points. Manual process can only be done in the form of quality control after the software has done the classification, because it would otherwise take too long time. Today, the Swedish National Land Survey uses a software called TerraScan, but they are interested in what the market has to offer besides TerraScan and what these other softwares can bring in quality and usability. Therefore, four softwares were chosen to evaluate their ground filtering ability of laser data. Information on how each software works and its ability to change settings is presented. The laser data used is selected to see how the software can handle different environments, and the known difficulties of “bare ground filtration” from the previous literature on the subject have been used to find these difficult parts. A qualitative and quantitative study is then made of the classified areas to find similarities and differences. The results give a clear picture of how the software performs. No software is flawless, where some have more problems than others but if you look at different factors and the overall package they offer, there are clear advantages for each of the software depending on the purpose of use. In the end there is really only one of the softwares that remain that is good enough for the Swedish National Land Survey, for the project that is currently being carried out, and it is the software already in use, namely TerraScan.
Andersson, Jonas, and Patrik Hedlund. "Undersökning om handhållna laserskannrar vid detaljmätning : En jämförelse mellan multistationen Leica Nova MS50 och den handhållna laserskannern FARO Freestyle X." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-22200.
Full textTerrestrial laser scanners (TLS) have been common in geodetic measurements for over 10 years. The technology is developing rapidly and specialized instruments are launched constantly. One type of these specialized TLS instruments are hand-held laser scanners. They are designed primarily to generate point clouds of spaces and small objects where the traditional tripod mounted laser scanner has difficulties to scan. When the hand-held laser scanners are relatively new, the research on the instruments is limited, and the lack of standardized control methods. With that in mind it is important to study the instruments. In this thesis the hand-held laser scanner FARO Freestyle X was investigated on how well the handheld laser scanning technology really is and what limitations the instruments have. This was done by comparing point clouds from FARO Freestyle X with reference point cloud generated by Leica's multi-station MS50. To study the instrument a number of parameters was investigated such as scanning distance, ease of use, time and performance. These parameters were considered to be sufficient basis for conclusions about the instrument's advantages/disadvantages and limitations. The result of the point cloud comparison from the short distance showed deviations around 10 mm and then increase to few centimeters at longer distances. Volume limitation control showed no differences compared to the scanning from short distance. This means that moving the instrument does not affect the results significantly. The instrument's Achilles' heel is the noise that occurs when scanning from longer distances, about 30 mm deviations. Even the type of object affects the noise. The noise on the wall showed the greatest deviation while the noise on the table indicated the lowest results. The repeatability showed good results visually and had similar deviations. The instrument has a good ability to recreate objects when the resolution test demonstrates good performance. Main advantage of the instrument is its effective documentation of smaller objects, but also some larger areas where the uncertainty of centimeter-level is required. The ease of use can be described as good and the colored point clouds takes visualization to a new level. The results of the study show that the hand-held laser scanners can, potentially, challenge the traditional laser scanner.
Bäckström, Morgan. "Insamling av höjddata med UAV : En jämförelse mellan laserskanning, GNSS och UAV." Thesis, Karlstads universitet, Institutionen för miljö- och livsvetenskaper (from 2013), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-68520.
Full textThe objective of the study was to compare elevation data, from UAV photo, with NRTK, trigonometric leveling and airborne laser scanning. The concrete issues to investigate were: • What quality is achieved by data acquisition using UAV, compared to laser scanning and terrestrial measurement with NRTK? • How much does different flight altitudes affect the result? The aerial photos were taken at 60 and 120 meters above ground, using seven flight support points and four ground control points. Those were measured with NRTK and terrestrial measurement. Collected images have been processed, with Agisoft Photoscan 1.4.2, into models in which coordinates are retrieved for comparison. The coordinates were compared and showed a deviation of 24 to 76 millimeters which is an acceptable result for a HMK standard level 2.
Björklund, Emil. "Uppdatering av den svenska nationella höjdmodellen : Förutsättningar för att använda mobil laserskanning." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-25884.
Full textIn this study the prerequisites for using data collected using mobile laser scanning are investigated for updating the Swedish national elevation model. In 2016, the Swedish Transport Administration started a project where information from the road network is collected with mobile laser scanning. The National Land Survey of Sweden has gained access to data from this project and wants to investigate the possibilities of using data from mobile laser scanning to update the national elevation model. The prerequisites for using data from mobile laser scanning to update the national elevation model is investigated by examining the deviation against measured control points, comparing height deviation between data from the national elevation model and mobile scanned laser data, as well as studying the distribution and completeness of data from the mobile laser scan is compared to the changed areas it is supposed to replace. The result shows a low deviation in height to the control points of 1.2 centimeter in mean deviation. The grid comparison also shows a low deviation in height, mean deviation -2.4 cm. The classification of the point cloud from mobile laser scanning shows problems in dense vegetation where there are no returns from the ground, which, along with restrictions on the spread of mobile laser scanning, impose restrictions on areas that can be updated. It is primarily the lack of ground points in the point cloud and that the point cloud does not fully cover the changed areas that limit the ability to use data from mobile laser scanning to update the National Elevation Model.
Ojamäe, Andreas. "Bildbaserad skanning och laserskanning av kulturhistoriska byggnader : En fallstudie på gasklockorna i Gävle." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-26986.
Full textLarsson, Alexander, and Olle Oscarsson. "Trädhöjdsbestämning med UAV-fotogrammetri och UAV-laserskanning : En jämförande studie för detektering av riskträd." Thesis, Högskolan i Gävle, Samhällsbyggnad, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-32699.
Full textUAVs (Unmanned Aerial Vehicles) or drones are commonly used for collecting spatial data and aerial images by companies, state agencies and civilians. The UAV techniques makes collection of geodata easier for large areas and can be used for mapping, 3D modelling and other analyses, e.g. for volume determination. The aim of this study was to compare 3D point clouds generated from airborne laser scanning and digital photogrammetry for detecting heights of trees. It was also investigated which method produced the most reliable results and if these were applicable for detecting risk trees. The definition of risk trees in this study are trees that run the potential risk of damaging important infrastructure such as electric power transmission lines. Nowadays the collection of data is mainly conducted using helicopters for identifying the risk trees, but with UAV technologies costs can be significantly reduced. The collection of data was performed over a sparse coniferous forest area in Gävle, Sweden. Laser data was collected using a YellowScan LiDAR (Light Detection and Ranging) sensor mounted on a drone. For the photogrammetric data, a DJI Phantom 4 RTK (Real Time Kinematic) drone was used with its standard camera. Both techniques were directly georeferenced using Single station RTK and SWEPOS Network RTK respectively. To check the quality of the collected data, six control profiles were established using a total station. These measurements were then compared to the generated point clouds. Our results show that the mean deviation and standard deviation in height between LiDAR point clouds and the control profiles are -0,038 m and 0,049 m, respectively. The mean deviation and standard deviation for photogrammetric point clouds and control profiles are +0,060 m and 0.090 m, respectively. These values were then compared to the requirements in SIS-TS 21144:2016. To determine absolute tree heights, ten random trees were measured using a total station. The coordinates of the highest and lowest points of each tree were then subtracted to serve as absolute height values. The comparison of the two UAV methods showed mean height deviations of -0,325 m for LiDAR and -0,928 m for the photogrammetry. This study concludes that LiDAR is the most suitable technology of the two methods tested for detecting tree heights and creating canopy height models. This is based on the obtained height values, the quality of the digital terrain model and the good distribution of points in plane and height for the point cloud.
Grötte, Louise, and Olov Häggmark. "Unmanned Aircraft System (UAS) för modellering och 3D-dokumentation av byggnader." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-23340.
Full textFjärdsjö, Johnny, and Zada Nasir Muhabatt. "Kvalitetssäkrad arbetsprocess vid 3D-modellering av byggnader : Baserat på underlag från ritning och 3D-laserskanning." Thesis, KTH, Byggteknik och design, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-148822.
Full textThe use of hand drawn construction model was the only way of development, rebuilding, sales and real estate management before the 80’s. However, the challenge was to preserve the drawings and maintain its real condition. To make things work faster and easier the development of advanced drawing software (CAD) was introduced which replaced the traditional hand drawn designs. Today, CAD is used broadly for all new constructions with a great success rate. However, with the new advanced technology many engineers and construction companies are heavily using 3D models over 2D drawings. The major advantage of designing in 3D is a virtual model created of the entire building to get a better control of input construction items and the errors can be detected at earlier stages than at the construction sites. By modifying buildings in a virtual model in three dimensions yet at the first stage and gradually fill it with more relevant information throughout the life cycle of buildings to get a complete information model. One of the requirements from the property owners in the redevelopment and management is to provide accurate information and updated drawings. It should be simple for the contractor to read drawings. This report describes a streamlined work processes, methods, tools and applications for the production of 3D models. This work is intended to lead to a methodology and to be used as well as for passing on experience. This report will also be a base to describe the approach to model from older drawings into 3D models. The method description will simplify the understanding of model for both the property owners and for companies who creates 3D models. It will also increase the quality of the work to create CAD models from the different data used for modeling.
Stråhle, Martin. "Noggrannhetsanalys hos mätmetoderna; RTK-mätningmed SWEPOS tjänst, GNSS-mätning med egenbasstation, laserskanning samt mätning medtotalstation." Thesis, Uppsala universitet, Byggteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-232855.
Full textForssén, Bengt. "Grundyteskattningars noggrannhet i barr- och lövskog inom projektet ”Skogliga skattningar med laserdata”." Thesis, Linnéuniversitetet, Institutionen för skog och träteknik (SOT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-38820.
Full textLjunggren, Carl, and Emil Lundgren. "Automatiska metoder för igenkänning, klassificering och extrahering av objekt från punktmoln insamlade med mobil laserskanning : En litteraturstudie." Thesis, Högskolan i Gävle, Samhällsbyggnad, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-29817.
Full textLarsson, Nils, and Caroline Jödahl. "TREDIMENSIONELL RELATIONSHANDLING FÖR BEFINTLIG BYGGNAD." Thesis, University of Gävle, Department of Technology and Built Environment, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-233.
Full textEn om- eller tillbyggnad av en byggnad kräver ofta att befintliga ritningar värderas med avseende på aktualitet och geometri. Ritningarna kan förekomma i form av 2D-ritningar eller som ett digitalt underlag. När ritningarna undersöks kan resultatet bli att dessa kräver en komplettering för att få ett relevant projekteringsunderlag eller en så kallad relationshandling. Befintliga ritningar kan ibland helt saknas och det krävs att nya relationshandlingar upprättas. I de fall där en osäkerhet finns om byggnadens geometri, genomförs en inmätning för att få en måttriktig relationshandling. Inmätningen kräver att mätdata efterbearbetas i CAD för att skapa en digital modell av byggnaden. Modellen utgör en relationshandling som kan användas av konsulter i projekteringsarbetet för den planerade ändringen av byggnaden. I allt fler projekteringsarbeten efterfrågas relationshandlingar där höjdinformation tillsammans med plankoordinater genererar så kallade 3D-relationshandlingar.
Syftet med detta examensarbete på C-nivå (10 poäng) har varit att i någon omfattning genomföra samtliga delmoment i upprättandet av en 3D-relationshandling. Inmätningen genomfördes med tre olika instrument: handhållen avståndsmätare, totalstation och laserskanner.Resultatet av bearbetning i CAD visar att modellering av mätdata från totalstationen och laserskannern ger ritningar som stämmer bättre överens med de faktiska förhållandena än de ritningar som generas från mätning med den handhållna avståndsmätaren.
Before the processes of rebuilding an existing building commence an evaluation of the existing drawings have to be done. Existing drawings can be either 2D-paper drawings or in a digital format. When evaluating the existing drawings one might find that these needs to be updated to serve as reference of basic data for the projection of the new building. A new 3D model has to be made. In some cases, there exist no drawings at all for an existing building that are to be reconstructed. The existing drawings can be found to have a deficiency with respect to geometry that calls for a survey of the building i.e. an as-built survey. The result of the as-built survey will need to be calculated and exported to CAD software for modelling. A digital model of the existing building is created in the CAD environment to. More of today’s work with basic data and the creation of digital models require height information in conjunction with the x, y coordinates in the purpose of creating a true 3D computer-based model.
The intentions of this thesis (C-level) have been to carry through all the parts needed in establishing a 3D computer-based model. The surveying was done in three different ways: with the use of a hand held laser distance meter, with a total station and finally, a scan was done using a laser scanner. A comparison and analysis using the three different methods where done. The result shows that the used methods can be useful by themselves or in conjunction with each other.
Gustafsson, Carolina, and Slavisa Mekic. "Flexibel mätcell inom flygplansmontering." Thesis, Linköping University, Department of Mechanical Engineering, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-3681.
Full textSaab Aerostructures i Linköping utvecklar och tillverkar flygplansstrukturer. Innan dessa levereras till kund ska de verifieras genom en slutkontroll och vid tiden för denna studie utförs slutkontrollen bland annat i kontrolljiggar. Dessa kontrolljiggar är produkt-specifika och mycket kostsamma att tillverka och underhålla.
Denna studie behandlar möjligheterna med att införa en mätcell, med tillhörande mät-system, istället för att använda kontrolljiggar för att utföra slutkontrollen. Vid detta införande skulle flera vinster kunna göras. En uppskattning har gjorts av vad det skulle kosta att använda sig av kontrolljiggar i två kommande projekt på företaget och detta har sedan satts i relation till kostnaderna med att investera i ett mätsystem. Vid en sådan investering kan flera intäkter väntas, men dessvärre har dessa övriga intäkter inte kunnat värderats i denna studie. Bland dessa intäkter kan nämnas att fler produkter skulle bli godkända direkt och produktionen underlättas, genom att produktens hela tolerans kan utnyttjas. Med de undersökta mätsystemen kan flexibilitet och mobilitet erhållas till skillnad mot användning av de produktspecifika och fasta kontrolljiggarna. Kontroll- och analysarbetet skulle minska och många förtjänster fås då all mätdata behandlas i datormiljö.
Vid en eventuell investering i ett nytt mätsystem, rekommenderas en lasertracker med T-Scan från Leica Geosystems. Detta gäller om investeringen kan visas vara lönsam med övriga intäkter inräknade. En beräkning har gjorts som visar att om de övriga intäkterna årligen uppgår till 300 000 SEK, är investeringen återbetald efter tre år.
Saab Aerostructures in Linköping develops and manufactures aero structures. Before these are delivered to the customer they have to be verified through a final control and at the time for this study the final control is performed in a control jig. These control jigs are specific for each product and they are very expensive to manufacture and to maintain.
This study handles the opportunities with introducing a measuring cell and belonging measuring system, instead of using control jigs to perform the final control. By this introduction several profits could be done. An estimate has been done of what the costs would be of using control jigs in two of the coming projects at the company and then this have been put in relation to the costs of investing in a measuring system. By such an investment several revenues could be expected, but unfortunately it has not been possible to value these in this study. Among these revenues it could be mentioned that more products would directly pass the verification and the production would be facilitated, by being able to use the entire tolerance of the product. With the investigated measuring systems flexibility and mobility can be gotten unlike using the product specific and fixed control jigs. The work with controlling the products and analysing the measuring data would be reduced and there are many good sides to the fact that all handling of measuring data are computer-aided.
If an investment in a new measuring system is to be made, a Laser Tracker with T-Scan from Leica Geosystems is recommended. That is if the investment can be shown to be profitable with the other revenues taken into account. A calculation has been made which shows that if the other revenues annually total 300 000 SEK, the investment is repaid after three years.
Axelsson, Henrik. "BIM : Förvaltning, inventering och användningsområden." Thesis, Mittuniversitetet, Avdelningen för ekoteknik och hållbart byggande, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-25158.
Full textBuilding Information Modeling, BIM is a complex idea which has varying meaning depending on where in the building process it is used. There is no simple definition of how the working with BIM is applied and consists of many areas of activity. This report is based upon the study of available literature and interview questions, which both have set the ground for the result and conclusions presented. These have aimed to investigate how digital information processing can be applied in the facility management for a building and furthermore, how inventory of an already built building can be improved by today’s technology. By studying what´s already have been written on the subject and contacting people who works in the building consulting business or building facility management, a combination of available techniques is presented. The bottom-line is that BIM (Building Information Modeling) is a modern working method which can be used by all disciplines for applying information to a project, and which also can be used progressively into production, facility management, rebuilding and renovation, and finally deconstruction. Inventorying of an old building which lacks data can be recreated by the use of laser scanner technique and gives a reliable collection of data, which afterwards is processed in a CAD program. Studies have been made in order to find a way for localizing inbuilt material without making any permanent damage to the building construction.
Sundqvist, Filiph, and Peter Tannebo. "Mätosäkerhet vid deformationsmätning med bärbar laserskanner." Thesis, Högskolan i Gävle, Samhällsbyggnad, GIS, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-25116.
Full textMobila bärbara laserskanningssystem, även kallade personliga laserskanningssystem (PLS), har potentialen att kombinera styrkorna hos fordonsburen mobil laserskanning (MLS) med användbarhet inomhus och i svårtillgänglig terräng. Mobiliteten innebär även möjligheter att mäta där terrester laserskanning (TLS) är svårt eller resursineffektivt att använda vilket kan göra PLS både lämpligt och fördelaktigt för viss deformationsmätning. Ännu är det dock inte klarlagt hur låg mätosäkerhet som kan nås och därmed hur små deformationer som kan uppmätas, varför den här studien avser att kontrollera det med ett ryggsäcksmonterat PLS. Via en litteraturstudie ges först en översikt av deformationsmätning och därvid möjliga sätt att kontrollera mätosäkerheter. Olika sätt att georeferera punktmoln beskrivs inklusive den nya tekniken Simultaneous Localization and Mapping (SLAM). Till sist gås tidigare studier av mätosäkerheter med MLS, PLS och SLAM igenom med fokus på metoder och resultat. Ett ryggsäcksmonterat PLS (Leica Pegasus: Backpack) används för att mäta simulerade deformationer både utomhus, inomhus och med tillägg av stödpunkter. Rotationer samt horisontella och vertikala deformationer testas (i intervall om 5° mellan 5° och 20° respektive 0,050 m mellan 0,050 m och 0,200 m) tillsammans med ett stillastående objekt. Genom att optimera skanningsslingan med hjälp av SLAM och analysera geometriska plan inpassade i punktmolnen, kan slutsatser dras om såväl hur små deformationer som kan uppmätas som om variabiliteten i mätningarna. Resultaten tyder på att rotationer på 5° kan mätas utomhus, men inomhus gör de kraftigt varierande mätosäkerheterna att rotationer på 20° och mindre inte kan mätas.Horisontellt och vertikalt kan deformationer på 0,050 m mätas utomhus, men inomhus kan endast vertikala deformationer med stödpunkter mätas (dock ner till 0,050 m). En slutlig analys av stillastående objekt visar på en sammanlagd standardosäkerhet i 3D på 0,001 m i utomhusmätningarna, 1,49 m i inomhusmätningarna utan stödpunkter och 0,490 m i inomhusmätningarna med stödpunkter. Resultaten visar på att flera faktorer måste tas i beaktning vid inmätning men också att potentiella användningsområden finns utomhus inom analys av katastrofområden, geomorfologiska förändringar av landformer, skogsbruk och detektion av urbana förändringar. Inomhus kan resultaten förbättras av mer avancerade SLAM-algoritmer tillsammans med stödpunkter, men mätosäkerheterna tyder ändå på att det framförallt är grov förändringsdetektering som är möjlig.
Andersson, Elias. "Dokumentation av en trafikolycka med handhållen laserskanning och UAS-fotogrammetri : En utvärdering av punktmolnens lägesosäkerhet och visuella kvalitet." Thesis, Högskolan i Gävle, Samhällsbyggnad, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-36472.
Full textIn the event of a traffic accident, it is often important to restore the site to its normal condition as fast as possible. Occasionally, the accident scene must be documented so that the cause of the accident can be investigated at a later stage. Traditionally, this work has been performed by taking pictures of the site and measuring different distances. Lately, terrestrial laser scanning has also become a reliable alternative. With that said, it is possible that photogrammetry and other types of laser scanning also could be utilized to achieve similar results. The aim of this study is to investigate how handheld laser scanning and UAS photogrammetry can be used to document a traffic accident. This is achieved by examining the positional uncertainty and visual quality of the point clouds. Moreover, the advantages and disadvantages of each method are explored, for instance in terms of time consumption and costs, in order to finally come to a conclusion of which method is best suited for documenting a traffic accident. A traffic accident with two involved cars was staged and initially laser scanned with the handheld laser scanner Leica BLK2GO. Thereafter, pictures were collected with the unmanned aerial vehicle Leica Aibot followed by the creation of a reference point cloud with the terrestrial laser scanner Leica C10. By comparing the coordinates of control points in the reference point cloud with the coordinates of the corresponding control points in the two other point clouds, their positional uncertainty could be determined. The results of the study show that both the point cloud produced by the handheld laser scanner and UAS photogrammetry have a positional uncertainty (standard uncertainty) of 0.019 m. Both methods are applicable for documenting a traffic accident but compared to terrestrial laser scanning, the point clouds are deficient in different ways. BLK2GO produces a relatively dark point cloud and dark objects are reproduced worse than lighter objects. In the point cloud produced by Leica Aibot, there were noticeable cavities in the bodies of the cars. Handheld laser scanning is a time-efficient method while UAS photogrammetry can be performed at a lower cost. In conclusion, it is not possible to arrive at an unambiguous conclusion with regards to which method that is best suited for documenting a traffic accident. The choice depends on the prevailing circumstances at the accident scene.
Eriksson, Anton. "3D-laserskanning och ytors egenskaper : En studie om semi-transparanta ytor, glans och de vanligaste felen vid skanning." Thesis, Umeå universitet, Institutionen för tillämpad fysik och elektronik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-136353.
Full textBergström, Eric. "Användning av LiDAR och ArcGIS inom skogsbruk i Sverige." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-12605.
Full textLight Detection And Ranging (LiDAR) has in the past decade developed a lot and is used as a data collection method for inventory of forest. The Swedish National Land Survey is between 2009 and 2015 carrying out a nationwide airborne laser scanning throughout Sweden, and this laser scanning process will lead to a new national elevation model called NNH. Data generated from this height model can be used by the forest industry to make forest inventories. The software developer ESRI Inc. has developed a support for handling LiDAR data in their new version of ArcGIS, ArcGIS 10.1. The purpose of this study is to investigate how the forest industry in Sweden are using LiDAR data, identifying gaps and needs, how ArcGIS is used and how ArcGIS can be developed to match the forest industry. This study was founded by comparing the new version of ArcGIS with the previous version and by interviewing six relevant people who are active in the industry. People from several stakeholders were interviewed: foresters, researchers and technical consultants.The results of the comparison between ArcGIS 10.0 and ArcGIS 10.1 show the potential of LiDAR data and how easy it is to deal with LiDAR data in the new version of ArcGIS. The results of the interviews show that the data available from the NNH are fully sufficient for forest inventory at stand level. It is however not sufficient for analysis of individual trees. Some of those interviewed experienced ArcGIS as an advanced and time-consuming program to learn while others emphasize that it will be interesting with support for managing LiDAR data. The interviewed consultants mostly use software that they have developed by themselves for managing LiDAR data, while other interviewees use ArcGIS as the main program. ESRI Sweden was not sure of the quality of the NNH and how much the forest industry uses NNH, before this study. But it turned out that the NNH data are widely used already, and that quality is adequate. ArcGIS is sometimes perceived as an advanced program and it has often to do with time constraints. If time is available the problem often can be fixed. LiDAR, and NNH is good and useful now, but the question is what will happen when it's time for the forest companies to make their next inventory?
Edbor, Simon, and Stefan Modin. "Punktmolnshantering i anläggningsprojekt : Utvärdering av programvaror för framtagande av markmodell." Thesis, Uppsala universitet, Tillämpad mekanik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-257385.
Full textCedergren, Lucas, and Richard Paakkonen. "En jämförelse mellan TLS och UAV-fotogrammetri : Inmätning av hårdgjorda ytor." Thesis, Uppsala universitet, Byggteknik, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-257679.
Full textBeck, Jonas, and Läthén Klas Brorsson. "Visualisering av brottsplatser." Thesis, Linköping University, Department of Science and Technology, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-6274.
Full textDetta arbete har gjorts i samarbete med Rikspolisstyrelsen för att ta fram en metod för hur modern medieteknik kan användas för att skapa en ”virtuell brottsplats”. Syftet är att arbetet ska leda till ett förslag till en metod som lämpar sig för att integrera i polisens brottsplatsundersökningar och rättsliga processer, med beaktande av de speciella krav som ställs.
Arbetet innehåller två huvuddelar där den första delens utgångspunkt är vad som går att göra med utrustning och teknik som redan finns tillgänglig och den andra delen hur det skulle kunna utvecklas vidare. Till första delen har ett förslag på en metod som kan användas för att utnyttja panoramatekniken, tagits fram. Därför har det också genomförts utvärderingar och tester på befintliga programvaror för att utröna vad som passar syftet bäst. För den andra delen togs en egen lösning fram och implementerades i OpenGL/C++. Denna lösning baseras på laserskanningsdata. Resultatet av denna del är inte en färdig metod som kan börja användas direkt utan mer ett exempel på hur panoramatekniken kan användas till något mer än att bara visa hur en plats ser ut. För att knyta samman projektet med verkligheten har båda dessa delar tillämpats på flera riktiga fall.
En slutsats som kan dras av arbetet är att visualiseringar av denna typ är väldigt användbara och till fördel för utredare och åklagare. Det finns mycket kvar att undersöka men det är ingen tvekan om att den här typen av teknik är användbar för detta syfte.
Brossard, Isabelle, and Christine Weissmann. "Påverkan av högreflekterande ytor vid användning av Romer Absolute Arm med integrerad skanner." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-19862.
Full textLaser scanning is known not to give good results with highly reflective surfaces. The issue is particularly visible when scanning with a close-range laser scanner, as the instrument is often used to digitalize objects of polished metal or other highly reflective material. In this case, it causes a significant increase of uncertainties and deviations. In some cases, it is not even possible to get data to work with. It is thus important to know how high reflectivity influences the results of laser scanning. The aim of this work was to investigate how deviations vary when scanning highly reflective surfaces. By knowing more about how influential different sources of uncertainties are on the use of a particular instrument, it is easier to decide on the right instrument and the right method for a particular project. The study was conducted by scanning and probing objects of different forms and reflectivities. The handheld line scanner Romer Absolute Arm with integrated scanner was used for scanning and probing. The data analysis was operated in Polyworks, which is the recommended software for the scanner. The results from the study show that scanning highly reflective surfaces gives poorer results than scanning surfaces with low reflectivity. However, the results can be improved by learning to use the scanner appropriately, and take into account the surface characteristics and the scanner’s settings. The conclusion is that the handheld scanner is a flexible and user-friendly instrument, but needs training and experience to be used at its full potential.
Gustafsson, Annika, and André Jägerev. "Strandfastigheters gränser : En studie av gränser i vatten." Thesis, Högskolan Väst, Avd för naturvetenskap, lantmäteri- och maskinteknik, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hv:diva-6927.
Full textWater areas and beaches were during the 18- and 19 century's very low graded (waste land) because it was not possible to grow any crops on the grounds. The same properties are today highly regarded real-estate. People buy beach front properties as summer homes or as permanent living, in a low stress environment. Because of this, the establishment of the estates boundaries can create problems when new beach front properties are created. The problems are usually linked to where the land boundaries really are located and where the property-owners consider it to be. To establish where the boundaries really are located the surveyor must perform a thorough archival research on the original property. The purpose of this study was to investigate how the establishments of the estates boundaries are performed today. Questions to answer are: How are the boundaries' established legally? How accurate are the boundaries in water areas, and have the uncertainty of the 3 meter depth curve any influence on the boundaries? Can the bathymetric laserscanner, compared with the current method, be a suitable method to establish the boundaries of beach front properties? The method selected in this study was qualitative interviews. The interviews were performed with experienced people from the Swedish "Lantmäteriet" and the company Airborne Hydrography AB. The theory was divided in three parts. Part one addresses "Lantmäteriets" role and workings with creating beach front property. Part two addresses the laws involved in creating beach front property. Part three addresses bathymetric laserscanning and the technical accuracy the instrument are capable of. The result shows that the accuracy of the boundaries in water areas are difficult to assess due to lack of references that often are missing and the shoreline is hard to locate. Laserbatymetri can in certain cases have a positive effect on beach front properties boundaries border setting in water areas and help the surveyor. The conclusion is that the surveyor must undertake an extensive archival research to find the shoreline and it is more difficult the older the original properties are. By examining the current method of establishing these boundaries and mix the result with the bathymetric laserscanning method the authors found a possible solution for the uncertain boundaries of water areas. The shoreline, 300meters boundary line and where the 3 meters depth curve is located
Forsberg, Viktor, and Filip Granström. "Jämförelse av karteringsmetoder inför bergklassificering i tunnlar." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-296425.
Full textSafety is always a primary concern during construction, even during tunnel construction. To prevent rock fall or sliding of blocks the rock has to be examined and classified. The tunnel examined in this report costs about 7000 SEK/hour to construct. Therefore, a lot of money can be saved by streamlining the work process, including mapping of geological structures. In this paper three mapping methods are compared, such as traditional geological mapping, photogrammetry and laser scanning. The Q and RMR index from the three different methods are then compared with respect to the various parameters included in the classification systems. The purpose of this study is to find out whether the new mapping methods have any financial and/or safety benefits, as well as any potential benefits in terms of storage in digital format of information about the rock quality and features, or not. The purpose is also to examine if the new technologies could replace the traditional mapping method fully or partially. Laser scanning and photogrammetry cannot completely replace today’s conventional mapping. This is because some of the parameters are not possible to be observed and interpreted in the produced digital models, but must be done in situ. However, there are other benefits of the digital methods such as digital storage capabilities, detailed, easily interpretable models and that it takes less time to map large areas or long distances.
Sundlöf, Martin, and Hans Persson. "Automatisk identifiering av branter för orienteringskartor." Thesis, Högskolan i Gävle, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-10930.
Full textOrienteering is a sport where the purpose is to visit a number of predefined control points using a map. The orienteering map shows various objects such as rocks, pits, knolls and cliffs. It is expensive and time consuming to produce an orienteering map. Approximately 120.000-150.000 SEK and 20–30 h/km2 field work is invested in every map produced. Considering orienteering maps are financed by non-profit orienteering organizations every time and money saving process is welcome. In this degree project a function has been created in a software called OL Laser. The aim of the function is to automatically identify cliffs in laser data for the usage as base maps in the production of orienteering maps. First the definition for cliffs in orienteering was defined. To be classified as a cliff three requirements had to be fulfilled, namely at least 1 m in height difference, at least 1 meter wide and a gradient greater than 85°. These requirements were determined by supplementing the existing restrictions specified in the regulations for orienteering maps with own measurements in three different reference areas around Gävle. The function was programmed so that a search in a height raster was started. Step by step the raster was scanned for pixels that meet the given parameters of the height difference, the width and gradient. The values of the parameters were determined by calibrating the function in the reference areas. The calibration was made to make it possible to automatically identify cliffs. The settings of the parameters used in the function after the calibration were 42.5° gradient, 0.6 m height difference and a propagation of at least two consecutive pixels. The pixels that the function identified as a cliff is the result. The result shows that the function is able to automatically find the cliffs, even in areas which it is not calibrated against. To be able to use the cliffs on an orienteering map, the cartographer has to verify the result of the function in the field. Both time and money is saved by using the function when producing orienteering maps.