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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.
71

Evaluation of Monocular SLAM Algorithms for Indoor Quadcopter

Röjder, Tomas January 2024 (has links)
No description available.
72

Adaptive search patterns for utility mapping with GPR

Sjöberg, Erik January 2024 (has links)
Ground-penetrating radar (GPR) is often used to locate utilities like pipes and cables in the subsurface. In many GPR surveys, a full grid pattern is performed even if the goal is to locate just a few utilities. This approach results in extended operational time. The aim of this project was to develop an adaptive search pattern for utility mapping that uses as short a path as possible, and that could be applied to an autonomous single-channel GPR system in the future. The search pattern was developed and simulated with Python. Animation and static plots were generated to demonstrate and evaluate its performance. A few pipe configurations were created for testing and performance evaluation. The result of the project is a search pattern that can traverse and map a network of utilities. It is able to find and map most pipes in test configurations but there are corner cases that need more attention. It can be used as a guide for a human operator, which means that a computer tells the operator how to move the system. The efficiency of the search pattern was evaluated. On a fairly sparse network of pipes, it can reduce the time consumption by at least 50% compared to the corresponding grid search.
73

Robotized rotor plate installation for a BLDC motor

Wallin, Elias, Cerin, Axel January 2024 (has links)
Industrial robot technology plays a vital role in modern production processes. The tools that this technology provides, excels at performing repetitive tasks and does so with precision, speed and strength far beyond human capability. This can both cut cost and ensure a higher quality standard. This thesis report presents a solution for automatic installation of rotor plates for a BLDC PM-motor. The motor design is under development at Uppsala University and is continually worked on during some of the University's courses within electricity.  In addition to potential industry applications, findings in this study are of interest in the development of laborations for robotics courses at Uppsala University. The production process developed within this study was carried out with an ABB robot arm, which is a flexible machine commonly used for industrial applications. A specialized tool was manufactured and mounted on the robot, in order to properly grab and install the rotor plates. Different types of mechanisms were evaluated when designing this tool. It was decided that a mechanical gripping tool would be most suitable for the task as it would be able to lift multiple plates simultaneously, thus saving large amounts of time. To make this tool an already existing gripper was used and then specialized fingers were constructed and installed on the gripper. The gripper was then paired with a collaborative robot.  A test rig was made to closely resemble the actual assembly situation. There, the tool proved to be able to lift the rotor plates without much of an issue. However due to the very narrow margin between the holes in the plates and the guiding rods they were supposed to be mounted onto, installing the plates proved to be very challenging. Many methods were tested in order to make the installation possible, but none were successful until the margin between the rods and the holes were increased. After this, the robot was able to grab, lift and install the plates in a smooth continuous motion.   An overall concept for the assembly process was created, this involved the plates traveling on a conveyor belt, then picked up by a robot, installed onto the rotor which was mounted in a rotary table. Photoelectric sensors were utilized in order to determine the position of the plates on the conveyor. Later this assembly solution was simulated using ABB Robotstudio. It was estimated that, with this assembly solution, it would take roughly 170 seconds to install all the plates for one rotor. This result was seen as promising and it is plausible that further development of this concept could lead to an efficient assembly process.
74

A NEW HANDS-FREE FACETO FACE VIDEOCOMMUNICATION METHOD : Profile based frontal face videoreconstruction

Li, Songyu January 2018 (has links)
No description available.
75

Automationsunderlag för stackningsmoment av kärnläggning

Berntsson, Mathias, Vernersson Krook, Gustaf, Thunberg, Karl-Johan January 2020 (has links)
Efterfrågan av energi ökar på grund av den ökande globaliseringen i världen. För att transmittera och distribuera elektrisk effekt används transformatorer. ABB Power Grids AB är världsledande inom produktion av transmissionskomponenter däribland högspänningstransformatorer. Transformatorer är tidskrävande och komplext att tillverka vilket har lett till att all produktion hos ABB Power Grids idag sker manuellt. En av transformatorns mer framstående komponenter är kärnan som bidrar med en effektivare reglering till mindre förluster. Kärnan konstrueras av tusentals tunna elektroplåtar som staplas omlott på varandra och vävs ihop till en sammanhängande struktur, detta enligt ett kärnläggningsmönster. Plåtarna i sig är otympliga att hantera då de är långa, tunna och vassa. Manuell stackning av elektroplåtar har visat sig ge upphov till en del skador då lyften är många och slitsamma, därtill har plåtarna legat till grund för otäcka skärskador. I och med detta har ett intresse för automation väckts i hopp om att reducera arbetsskador. Vid första anblick kan kärnläggningen anses vara perfekt för automation då arbetsmomentet är enkelt och repetitiva. Incitamentet för automation ökar ytterligare i hänseende till arbetsmiljön. Komplikationerna uppstår när arbetet bryts ner. Under ytan är det en utstuderad process där krav på produkt är höga med strikta toleranser. Därtill har arbetet beskrivits som något man behöver en viss känsla för då arbetet anpassas genom hela processen. Detta försvårar automation betydligt då dagens tillverkningsprocess är svår att fullt ut härma med robotar eller portaler. Därför behövs avgränsningar behöver göras för att hitta avvägning mellan slitsamt arbete och finess. Området för automation begränsas därför till stackningsprocessen. Genom att fokusera på stackningen flyttas de slitsamma och farliga lyften från manuell arbetskraft till automation samtidigt som kontroll, justering och slutmontage behålls manuellt. På så sätt kan produktionen av transformatorkärnor göras lämpad för automation då det allra mest tidskrävande momenten inte behöver utföras av människan. Detta är innebär emellertid inte att automation görs utan svårigheter. Kärnornas storlekar samt den precision som krävs vid läggning sätter höga krav på den automationslösning som ska implementeras. För att en automationslösning ska klara av att stacka alla de typer av kärnor som idag tillverkas på ABB Power Grids kommer stora strukturer behöva upprättas för att utföra arbeten med extrem precision. Detta sätter höga noggrannhetskrav på de automationsmodeller som upprättas. Vidare, produktionsområdet där automation idag avses är väl utstakat och anpassat efter manuellt arbete. Detta innebär att automationsmodeller som idag finns på marknaden behöver omarbetas för att passa in i dagens produktion hos ABB Power Grids. Slutligen måste frågan ställas om modifierade lösningar kan göras noggranna nog eller om större ingrepp på produktionsområden behövs göras. I förstudien presenteras olika automationsmodeller som har utvecklats för att integreras hos ABB Power Grids, dessa är Portalmodeller, Länkarmsmodeller och Inmatningsmodeller. Utformningsförslagen har sedan analyserats och jämförts för att ge ABB PG ett utgångsläge för vidareutveckling av automatisering av stackningsmomentet. Resultatet blev fem automationsmodeller, två använder sig av länkarmsrobotar och tre är portaler. Vidare så har två automatiserade inmatningsmodeller upprättats för att ytterligare reducera den manuella hanteringen av elektroplåtar. ABB Power Grids rekommenderas att inledningsvis gå vidare med Robotmodell 1.
76

Automatisk kollisionsundvikande bärhjälp för livsmedel : med fokus på analys av metoder för objektspårning i bild

Pihl, Jacob, Tataragic, Edin January 2017 (has links)
No description available.
77

Terrain Mapping Near the Vehicle, SLAM and Global Map Building for Lunar Rover

Rajendraprakash, Anuraj January 2013 (has links)
There has been increasing interest to go back to the moon in the recent past because of various scientific and socio-economic reasons. In order to go back to the moon there is a need to study the lunar environment. Although having a permanent mission outpost on the moon is the final goal it is better to send mobile rovers to the surface of the moon first to study lunar environment before starting the human missions to moon again. With the increasing autonomous mobility of the lunar rovers some aspects become increasingly important namely localization, navigation and mapping. Although the two-dimensional localization and mapping algorithms are becoming more and more mature for indoor mobile robotics, they cannot be used, as is, for autonomous lunar rovers. The terrain on the Moon is not even and would have various kinds of obstacles for the rovers to manoeuvre and traverse. Moreover, environmental features like walls and corners are not available in the environment in which the rovers would have to navigate. In such environments it becomes important for the rover to have the ability to map its surrounding in three dimensions. Although LIDAR based systems have not been widely used on actual lunar missions for mapping yet, they have the advantage of being more accurate and long-range. The focus of this thesis would be to develop and equip a lunar rover prototype with the three-dimensional terrain mapping ability using LIDAR sensor which would help the rover to traverse its environment without collisions. A three-dimensional point cloud was used to map the environment using the Iterative Closest Point(ICP) algorithm. / <p>Validerat; 20131031 (global_studentproject_submitter)</p>
78

Computer vision for automatic opening of fuming slag-furnace

Burman, Hannes January 2021 (has links)
This thesis covers the implementation of visual algorithms for a robot that is to operate at a smelter furnace. The goal is for the robot to replace a human in the opening, closing and flow regulation process as danger can arise when 1300°C slag flows out of the furnace. A thermal lance is used for opening the furnace which means the robot also has to understand if the lance is burning or not. A heat camera with temperature intervals 0-660°C and 300-2000°C was used to record the furnace during these critical moments which has been used to test different vision and tracking algorithms, such as mean shift and continuously adaptive mean shift. The heat images were filtered to extract only the relevant slag flow part, which then were used to track if slag was flowing, and see how large the slag flow was. Opening of the furnace was possible to identify for both temperature intervals. For the closing of the furnace both intervals were also successful, but the lower interval used a different algorithm for this case to be successful. A relative slag flow has been identified which looks promising for further real life studies. The ignition of the lance result is inconclusive as the data recorded was not fit for analysing this case, though a few conclusions could be made indicating a thermal camera may be unfit to track the thermal lance state.
79

Kriterier för automation vid inlagring : Ett beslutsunderlag i valet av artikelplacering / Criteria for automation during the put away process.

Svensson, Simon, Wadsten, Adam January 2019 (has links)
The role of warehouse in the value stream, plays a significant part in how well a company can satisfy the requirements of a customer. To be able to support the demand of the customers, production companies are forced to produce a bigger variety of models in the product range, which results in an increasing assortment. With an effective stock keeping, there is a potential to reduce waste and increase profitability. In the choice of warehouse-design, warehouse-operations have the opportunity of choosing between a number of different designs containing manual and automated put away.It has become common that companies are choosing a combination of automated and manual processes. With this combination of processes, the companies are faced with choices about stock locations. With the help of well developed criterias about stock locations, there is a potential to achieve a more effective put away. The purpose of the study has been formulated as ”Investigate when automation in warehouse management makes the put away process in a central warehouse more efficient”.   Through a case study on a warehouse, located in Nässjö, this report will answer the research questions regarding which of the manual and automated put away processes to use. The research questions are: Which criteria affect the decision of automated or manual put away? Based on the criteria that are raised in research question 1, when is it more efficient to store carton in AS/RS in comparison with manual picking with truck in pallet racking? The research questions wish to lift criteria as a basis for decision making and when it is more effective to use automated put away. The warehouse that this study is based on is using both automated and manual materials handling. The specific automation system that has been the basis for this study’s result is AutoStore. This report has a qualitative approach, the methods that has been used for collecting data are interviews, observations and document studies.   Dimension, process time and utilization were the three criteria that are presented in the result. Based on the pallets limit of space in the automated system, the dimension of the article is the first criteria. In addition to the article’s measurements, the articles shape and material of the package had an impact if the article would fit in the load carrier. The two put away processes include different operations that differ in how long they take to execute, which has an impact on the company's efficiency. One reason for the time consuming difference, turned out to be how the quantity affects the time for put away in AutoStore comparing with the constant time for manual put away. A time consuming operation in the process with AutoStore was the one with repacking for the systems pallet. The operation also turned out to affect the utilization rate, due to its measurement of a pallets fill rate.  The quantity of put away in combination with the dimensions of the article, affects the total utilization rate.   With the result, the aim of the study is to contribute to companies that contains a combination of warehouse-design with a basis for the decision making about stock locations.
80

Application and Control of Robotic Manipulator through PLC

Fredmer, Andreas January 2017 (has links)
This thesis analyses the background of the kinematics and control of an articulated robotic arm in order to control it’s motor controllers with a custom controller using PLC programming. The goal was to create a MATLAB simulation of a manipulator and then establish a working configuration. This would then later be used by the division of Signals and Systems at LTU to educate students in PLC programming for autonomous setups with the robotic manipulator. The thesis was successful following the schedule established at the beginning and most of the objectives were accomplished. The results were a functioning control framework of Siemens PLC that could control the manipulators motor controllers to preform pickand place tasks in conjunction with a conveyor belt.

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