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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Testování automatického měřícího systému / Testing of automatic measurement system

Hromková, Zuzana January 2015 (has links)
The thesis deals with testing of the automatic measurement system, namely of the system for monitoring civil engineering structures Trimble 4D Control. A summary of the basic principles of deformation monitor is given at the beginning of the study and is followed by an overview of the system´s structure. The activities carried out under the pilot project (beginning with the installation of the system and finishing by the evaluation of the measured data) are described. The project demonstrated by the functionality, reliability and usability of the systam for monitoring of the structures.
12

Vytvoření účelové mapy nádvoří hradu metodou laserového skenování / Creation of a purpose map of the castle courtyard by the laser scanning method

Kučeravý, Peter January 2021 (has links)
This diploma thesis is dealing with creation of thematical map of castle courtyard of the Veveří castle using the method of laser scanning. The thesis describes the construction of a survey net which is important for measuring control points and then scanning of the area using the scanner FARO Focus 3D. The thesis contains a description of the method of laser scanning and point cloud processing in Trimble RealWorks software. Furthermore, this thesis deals with the accuracy of the point cloud and compares the laser scanning method with the typical tachymetric method according to time duration.
13

Sebelokalizace mobilního robotu ve vnějším prostředí / Outdoor Mobile Robot Self-localisation

Sárközy, Gabriel January 2012 (has links)
The aim of this work was to create a self-localization unit. The basis of the unit is an electronic platform Netduino Plus, which is connected with a measurement unit MTi-G and a camera based sensor, which is able to detect the position of points on the schools testing polygon. Configuration of the measurement unit MTi-G was done by a modified previously developed program. The program of the platform uses lover level communication with the sensor without using predefined classes from the manufacturer. This should improve the speed of processing the data from the sensor. To check the accuracy of the position provided by the self-localization unit another program was created. This program receives messages form a more accurate localization system that is mounted to the robot. The localization system is based on Trimble DB982 receiving modules.
14

Jämförelse mellan två generationer av GNSS-mottagare tillverkade av Trimble : Mätnoggrannhet i plan och höjd vid användande av nätverks-RTK / Comparison of two generations Trimble GNSS receivers

Gunnarsson, Anton, Ström, Martin January 2020 (has links)
The use of GNSS has made huge progress over the last few decades and in many cases replaced the use of total stations. A current problem for the GNSS-technique is dense vegetation, which prevents the receivers from making reliable calculations for the satellite signals. In this study a new receiver from Trimble that is said to be able to measure in these particular environments is compared to its predecessor. By assignment from ÅF Karlstad we have therefore conducted a comparison of the new receiver (R12) and its predecessor (R10), to see if R12 to a greater extent than R10 can replace the use of a total station.   The comparison was carried out by repeatedly measuring six different points, totally or partly obstructed by vegetation. To achieve uniform points these where measured with a Realtime Updated Free Station (RUFRIS) and the altitude was balanced from nearby fixed points.   The results where then analyzed by calculating average distance from the known points as well as the maximum dispersion within each respective moment of measurement. The results show that Trimble R12 can conduct reliable measurements in environments where the R10 is not useable. At one of the points the R12 achieved fixed solution where the R10 failed to do so, which is clearly reflected in the results. The results further show a more even and gathered result compared to the R10.   The conclusion of the project is that the R12 constantly performs a better result than the R10 and also enables measurements in environments previously not measurable with GNSS.
15

Accuracy and Precision Analysis of Total Station Measurements

Hägglund Eriksson, Malin January 2014 (has links)
The main objective of this bachelor thesis was to gain awareness of accuracy and precision in total station measurements. Experiments were designed, executed and analyzed.   The approach to the subject was to examine measurements made with various prism set-ups. Prisms are supposed to be directed to the total station with the front face in the line of sight. In the experiment the prisms were directed in various angles in order to measure in non-perfect measuring arrangement and the behavior of the precision and accuracy were noted.   The mean values and standard uncertainties were calculated from the material as well as RMS Error in the cases where reference values could be used as true values. The reference values for comparison were available due to the possibility to use a test field – a network of concrete pillars with well-defined coordinates.   To see whether the precision (the standard uncertainty) changed between a measurement sample made with correctly positioned prisms and a measurement sample towards the angled prisms, a statistical test method was used. (The test method is recommended in the international standard ISO 17123-1; Optics and optical instruments, Field procedures for testing geodetic and surveying instruments, Part 1: Theory).   The results from the experiments showed that there were larger standard uncertainties in the slope distance measurements towards extreme angled prisms than to correctly directed prisms. Surprisingly it was also larger standard uncertainty in vertical angle measurements toward correctly directed prisms than slightly angled prisms. The mean values of the horizontal angle measurement drifted sideways in the measurements made towards one extreme angle to the opposite extreme so that a total shift of around one centimeter was detected at short distances as well as up to 100 m distance.    When aiming in between the separate prisms of 360-degree targets the standard uncertainty were larger in horizontal angle measurements at a few occasions where it seemed like the autolock function had chosen two different prisms to lock on to, at separate occasions. The standard uncertainties were also larger in all vertical angle measurements when aiming in between the prisms.   The results showed clearly that even when the standard uncertainties of the measurements were of equal size, the mean values – when measuring in the different test positions – could vary substantially. / Huvudsyftet med detta kandidatarbete var att öka medvetenheten angående noggrannhet och precision i mätningar utförda av en totalstation. Ett antal experiment planerades, genomfördes och analyserades.   De områden som undersöktes i projektet var hur mätningarna påverkades av olika sätt att vinkla prismor mot totalstationen. Det rekommenderas att rikta ett prismas framsida mot totalstationens siktlinje. I experimentet vinklades prismorna i olika lägen för att mätningar skulle utföras i icke-perfekta förhållanden.   Medelvärden och standardosäkerheter beräknades ur mätdatan samt RMSE i de fall där det fanns referensvärden att jämföra med. Dessa referensvärden var tillgängliga tack vare möjligheten att få utnyttja ett testfält med betongpelare med kända koordinater.   För att utröna om precisionen (standardosäkerheten) ändrades mellan mätningar på korrekt inriktade prismor och de mätningar som gjordes mot vinklade prismor, utfördes ett statistiskt test. (Testmetoden rekommenderas i den internationella standarden ISO 17123-1, Optics and optical instruments - Field procedures for testing geodetic and surveying instruments - Part 1: Theory).   Resultaten av undersökningarna visade att där var större standardosäkerheter i mätningar av den lutande längden när prismorna var extremt vinklade än när de var korrekt orienterade. Standardosäkerheten var något överraskande också större med korrekt riktade prismor i vertikalvinkel-mätningarna med autolockfunktionen än om prismorna var något utåtvinklade. Medelvärdena på horisontalvinklarna drev sidleds i mätningar gjorda i en extrem vinkelposition till den motsatta extremen så att en total förflyttning på runt en centimeter konstaterades på korta avstånd likväl som på avstånd upp till 100 m.   Vid inriktning av siktet mot områdena mellan de separata prismorna i 360-gradsmålen så ökade standardosäkerheten i horisontalvinkel vid ett par positioner då det verkade som att autolockfunktionen valde båda prismorna på var sida, vid olika tillfällen. Standardosäkerheten var också större vid samtliga vertikalvinkelmätningar mot områdena mellan prismorna.   Resultaten visade tydligt att även om standardosäkerheterna i mätningarna var i samma storleks-ordning så kunde medelvärdena av mätstorheten mellan de olika testpositionerna variera substantiellt.
16

Utvärdering av mätosäkerhet för positionsbestämning med Trimble R12i och dess inbyggda lutningskompensator

Rage, Zakaria, Zerezgi, Natnael January 2022 (has links)
Geodetiska mätinstrument utvecklas konstant. Denna utveckling möjliggör attmätning med Global Navigation Satellite System (GNSS)-instrument nu kangenomföras utan att behöva horisontera stången som instrumentet ärmonterad på, detta eftersom själva mottagaren har en inbyggdlutningskompensator som konstant beräknar positionen för stångspetsen. Enav mottagarna som har en sådan inbyggd lutningskompensator är TrimbleR12i som lanserades 2020. Förutom att instrumentet kan mäta utan att varahorisonterat har mottagaren också andra funktioner som bidrar till förbättradpositionsbestämning, som en ny signalbearbetningsfunktion som gör att denpresterar bättre i svåra mätmiljöer, till exempel vid höga byggnader, underträd och så vidare. I den här undersökningen ligger fokus på hurlägesosäkerheten varierar mellan lutningsgraderna 0º, 10º, 20º, 30º, 40º och50º samt på hur tekniken presterar i svårare mätmiljöer med begränsad sikt.För att testa om tekniken klarar inmätning av dolda punkter i en svår miljö,genomfördes inmätning av fyra hushörn för en ca 17 m hög byggnad, somsenare jämfördes med inmätning av två hushörn för en lägre byggnad, cirka 10m hög. Något som också undersöktes var hur lägesosäkerheten påverkas avolika observationstider. De erhållna GNSS-resultaten jämfördes senare medreferenskoordinater. Dessa mättes in med totalstation från en station sometablerats med en GNSS-baserad stationsetablerings metod, nämligenrealtidsuppdaterad fri stationsetablering (RUFRIS) med 15 bakåtobjekt.Resultatet av mätningarna i olika lutningsgrad bekräftar det som var förväntat,nämligen att standardosäkerheten i både plan och höjd ökar i samband medökad lutningsgrad. De högsta standardosäkerheterna erhålls vid 40º och 50ºlutning. Resultatet bekräftar också att instrumentet klarar att prestera braäven i svår mätmiljö. Standardosäkerheten i plan på punkt C som ligger i ensvår mätmiljö hamnade mellan 1,8 cm till 7,6 cm vid 0º till 30º lutning och5 till 10 cm vid lutningarna 40º och 50º. De vertikala standardosäkerheterna ärmycket låga. I punkt A som befinner sig i en vanlig mätmiljö liggerstandardosäkerheten i höjd mellan 4 till 9 mm vid 0º till 30º lutning och 0,7cm till 1,7 cm vid lutningarna 40º och 50º. I den svåra mätmiljön ligger devertikala standardosäkerheterna mellan 2,1 cm till 6,9 cm vid 0º till 30ºlutning och 3,6 till 8,9 cm vid 40º och 50º lutning. De vertikala osäkerheternaökar också i samband med ökad lutningsgrad även om ökningen inte är likastor som för de horisontella osäkerheterna. Slutsatsen av undersökningen äratt instrumenten fungerar bra i svår mätmiljö med begränsad sikt medstandardosäkerhet på 1,8 till 7,6 cm i plan vid 0º till 30º lutning och 5,1 till 10cm vid 40º och 50º lutning. Det går också att genomföra mätningen med upptill 50º lutning, åtminstone i vanlig mätmiljö med standardosäkerhet mellan1,7 cm och 5,6 cm. I svår mätmiljö hamnar osäkerheterna på dm-nivå vidlutning ≥40º. / Geodetic measuring instruments are constantly developing. This developmenthas now made it possible to measure with Global Navigation Satellite System(GNSS) instruments without leveling the survey rod the instrument ismounted on. This is because the receiver itself has a built-in tilt compensatorthat constantly calculates the tip position of the survey rod. One of thereceivers with such a built-in tilt compensator is Trimble R12i, which waslaunched in 2020. In addition to the instrument being able to measure withoutbeing leveled, the receiver also has other functions that contribute toimproved position determination, such as a new signal processing functionthat performs better in challenging measurement environments, for exampleclose to tall buildings, under trees and so on. This study focuses on how theposition uncertainty varies between the tilt angles 0º, 10º, 20º, 30º, 40º and50º and how the receiver performs in challenging environments with limitedvisibility of the satellites due to different objects such as tall buildings andtrees. To test whether the technology can measure hidden points in achallenging environment, four house corners were measured for a tallerbuilding. This was later compared with two house corners measured beside alower building. It was also investigated how the position uncertainty isaffected by different observation times. The result obtained with the GNSSreceiver was later compared with reference coordinates that were measuredwith a total station that was established with real-time updated free stationestablishment (RUFRIS) relative to 15 network-RTK positions.The result of the measurements in different tilt angles confirms what wasexpected, namely that the standard uncertainty in both horizontal and verticalincreases with the tilt angle. The highest standard uncertainty was obtainedwith 40º and 50º tilt angles. The result also confirms that the instrumentperforms well even in a challenging measuring environment. The horizontalstandard uncertainty at point C (challenging measuring environment) isbetween 1.8 to 7.6 cm for 0º to 30º tilt angles and 5 to 10 cm at tilt angles 40ºand 50º. The vertical standard uncertainty for point A (normal measuringenvironment) is between 4 to 9 mm at tilt angles of 0º to 30º and 0.7 to 1.7cm at tilt angles of 40º and 50º. In difficult measurement environments, thevertical standard uncertainties are between 2.1 to 6.9 cm at 0º to 30º tilt and3.6 to 8.9 cm at 40º and 50º tilt angle. The conclusion of the study is that theinstrument works well in challenging measurement environments withstandard uncertainties between 1.8 to 7.6 cm in the horizontal at 0º to 30º tiltangles and 5.1 to 10 cm at 40º and 50º tilt angles. It is also possible to carryout measurements with a tilt angle up to 50º, at least in a normal environmentwith standard uncertainties between 1.7 cm and 5.6 cm. In challengingmeasurement environments, the uncertainties can be at dm-level at tilt angles≥ 40º.
17

Design Methodology for Modifying an Existing Internal Combustion Engine to Generate Power from a Stored Air System

January 2011 (has links)
abstract: A low cost expander, combustor device that takes compressed air, adds thermal energy and then expands the gas to drive an electrical generator is to be designed by modifying an existing reciprocating spark ignition engine. The engine used is the 6.5 hp Briggs and Stratton series 122600 engine. Compressed air that is stored in a tank at a particular pressure will be introduced during the compression stage of the engine cycle to reduce pump work. In the modified design the intake and exhaust valve timings are modified to achieve this process. The time required to fill the combustion chamber with compressed air to the storage pressure immediately before spark and the state of the air with respect to crank angle is modeled numerically using a crank step energy and mass balance model. The results are used to complete the engine cycle analysis based on air standard assumptions and air to fuel ratio of 15 for gasoline. It is found that at the baseline storage conditions (280 psi, 70OF) the modified engine does not meet the imposed constraints of staying below the maximum pressure of the unmodified engine. A new storage pressure of 235 psi is recommended. This only provides a 7.7% increase in thermal efficiency for the same work output. The modification of this engine for this low efficiency gain is not recommended. / Dissertation/Thesis / M.S. Mechanical Engineering 2011
18

Model rodinného domu v programu Revit / The model of a family house in Revit

Soukup, Štěpán January 2020 (has links)
This diploma thesis focuses on processing and data collecting for the use of creating functional 3D informating model that we call BIM (Building Information Modelling) which is getting more and more attention throughout building industry and it is used by all of the participants in the industry from designers and architects to those who are dealing with building installations. This process is slowly getting into legislations of many countries including Czechia. The thesis is divided into two parts where one of them is describing the Building Information Modeling in general and the other part is describing the work which is behind the colleting good data which is needed when making the 3D documentation in Revit software which is wildly used for designing building constructions. Practical part of the land surveyor´s work is devided here into two parts where one of them is dedicated to collecting data by laser scanning process, GNSS and measuring by total station and levelling machine. Second part focuses on the description of the data processing in order to make 3D model. The example of the output production data is the BIM 3D model of the family house in selected level of detail and besides that we also have the visualization of both interior and exterior and 2D simplified building documentations.
19

An assessment of the GPS L5 signal based on multiple vendor receivers

Smyers, Serena Ashley 21 February 2012 (has links)
The L5 signal of the Global Positioning System (GPS) is becoming available on an increasing number of Block IIF satellites. As the third civilian signal, L5 is superior in signal design to the L1 C/A and L2C civilian signals. This new signal has been marked healthy for use on selected satellites since 2010, yet the hardware capable of tracking the L5 signal is still in the early stages of development. This work investigates the characteristics of the new signal and the quality of data produced by L5-tracking receivers. Commonly used receiver models chosen for this study are the Leica GRX1200+GNSS, the Trimble NetR8, and the Javad Delta TRE-G3TH. The metrics used in this analysis to assess the quality of data produced by these receivers are signal strength, receiver phase noise, receiver code noise, and multipath. The data used in these analyses were obtained from the International GNSS Service for the days of the year 275 to 281 in 2011. Metrics averaged over the GPS week 1656 provide a good indication of the overall performance of the receivers. / text
20

Měřická dokumentace památkového objektu v areálu hradu Veveří / Metric survey documentation of historic building in the area of Veveří castle

Velecká, Kateřina January 2021 (has links)
The diploma thesis deals with the production of metric survey documentation of part of historic building in the area of Veveří castle, namely two buildings located on the so-called "Příhrádek" in the form of a ground plan and section in the scale of 1:50 and elevations in the scale of 1:100. The thesis contains a theoretical part describing methods of surveying monuments, their outcomes and used software. And a practical part that deals with the measurement itself and the following procession leading to the production of graphical outcomes.

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