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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.
81

Modeling, Identification and Control of a Wall Climbing Robot Based on Vortex Actuation / Modellering, identifiering och styrning av en väggklättringsrobot baserat på Vortex aktuator

Papadimitriou, Andreas January 2018 (has links)
No description available.
82

A Wavelet-Based Surface Electromyogram Feature Extraction for Hand Gesture Recognition

Forsberg, Axel January 2018 (has links)
The research field of robotic prosthetic hands have expanded immensely in the last couple of decades and prostheses are in more commercial use than ever. Classification of hand gestures using sensory data from electromyographic signals in the forearm are primary for any advanced prosthetic hand. Improving classification accuracy could lead to more user friendly and more naturally controlled prostheses. In this thesis, features were extracted from wavelet transform coefficients of four channel electromyographic data and used for classifying ten different hand gestures. Extensive search for suitable combinations of wavelet transform, feature extraction, feature reduction, and classifier was performed and an in-depth comparison between classification results of selected groups of combinations was conducted. Classification results of combinations were carefully evaluated with extensive statistical analysis. It was shown in this study that logarithmic features outperforms non-logarithmic features in terms of classification accuracy. Then a subset of all combinations containing only suitable combinations based on the statistical analysis is presented and the novelty of these results can direct future work for hand gesture recognition in a promising direction.
83

Automatic System Tests on Airborne Radar Systems

Lindblom, Sebastian, Johansson, David January 2018 (has links)
The aim of this master thesis was to create automated system tests on airborne radar systems. Automated tests can reduce time spent on repetitive and monotone work and instead create time for exploratory testing and customer criteria testing. Nightly builds and well designed tests can improve robustness and create a more stable system for the user. The project started with a pre-study, which consisted of researching the system in question, researching the possibilities of automated tests on said system and different tools that could be used in the project. Furthermore the pre-study contained interviews, visits and workshops within SAAB, with topics including automated tests, automation software and the SAAB GlobalEye system. The solution included two separated tests, one regression test and one startup test. The regression test verifies that selected standard functions works with the new soft/hardware updates and the Startup test verifies that the starting sequences for selected subsystems are executed correctly. Both of these tests were installed in the test laboratory. The tests were separated in to two parts; one control part and one analysis part. By recording the data being sent on the different interfaces while performing the tests, it's made possible to analyze the recorded data. This method enables many tests to be performed on the same set of data. The control part was solved with a third party software, called Squish, from a German company named Froglogic. The analysis part was written in MATLAB, where the test results were presented as well. The chain of events was set up and executed by Jenkins (an open source automation software), which also served as a scheduler, to enable nightly builds.
84

Modification of a transient EPR and photoluminescence detection setup

Grund, Olof January 2017 (has links)
Climate change has given rise to higher demand of renewable energy. Conventional non-organic solar cells are still seen the most on the market but the last 10-20 years there has been an exponential increase in research about organic solar cells. The research demands measurements done on increasing fast time scales as insights about the topic and technology develops. Here is presented configurations done at the Isaak spectrometer at Freie Universit\"{a}t Berlin. The spectrometer is used for studying charge transport in organic solar cells as well as hybrid solar cells made from organic and inorganic semiconductors. One important feature for the time response is the Q factor property of the resonator in which the sample is placed. The Q factor describes the rate of energy loss relative to the stored energy of the resonator. The Q factor dependency over different temperature was studied in order to gain vital knowledge about the time response of the setup. Further new equipment was been installed at the setup and programmed in FSC2. This in order to increase the sensitivity of the optical setup, secure the personnel from possible dangerous excitation laser and in order to do more automated measurements. As the optical path was modified by installing a new optical fiber a new calibration had to be done. Finally, in order to try the functionality of the new equipment an automated energy dependency measurement was done on the polymer MEH-PPV and the polymer:fullerene blend MEH-PPV:PCBM. The automatic process of measuring was successful.
85

Using an evolutionary algorithm to search for control algorithm parameters with a quadrocopter as hardware in the loop

Nyxén, Primus, Borgersen, Gustav January 2015 (has links)
This thesis describes the process of finding control loop parameters for a quadrocopter using machine learning techniques and a hardware in the loop evaluation method. A quadrocopter is an Unattended Aerial Vehicle (UAV) with four rotors that can be controlled individually to steer the vehicle. The purpose of the control loop is to keep the roll, pitch and yaw-angles of the quadrocopter to a predefined value by regulating the thrust of each rotor. A quadrocopter is designed and manufactured and a control algorithm is implemented on the built in controller board. An Evolutionary Algorithm (EA) is implemented on a Personal Computer (PC) and an automated search for control parameters using hardware in the loop with the quadrocopter as evaluation model is performed. The results show that a quadrocopter can be used together with hardware in the loop to improve the control algorithm parameters.
86

Simulation & integration av robot med stiftmaskin : En förstudie om   robotisering av stiftmaskin / Simulation & integration of a robot with apin machine : An prestudy of robotization of a pin machine

Cederqvist, Fredrik January 2017 (has links)
Denna förstudie behandlar robotisering av en process som monterar två stiftade tåtar i en plastkontakt, detta bildar ett kablage. Idag monteras tåten till plastkontakten manuellt. Förstudien undersökte om robotisering är tekniskt möjlig och ekonomiskt försvarbar. Robotiseringen sker genom att en robot fattar tag i en stiftad tåt i stiftmaskinen med ett gripdon, sedan förs den stiftade tåten in i en plastkontakt med hjälp av roboten. Stiftmaskinen är en Schleuniger 67 cc. Simuleringar av två koncept genomfördes med en mock-up av maskinen och ligger som underlag för de uppskattade cykeltiderna för den robotiserade processen. Två laborationer genomfördes för att undersöka svårigheterna vid robotiseringen av processen och om det är tekniskt möjligt. Första laborationen bestod av att utforma ett gripdon som kunde hantera produkterna utan att skada dem. Andra laborationen gav underlag för ett uppskattat kvalitetsbyte för processen.  Första laborationen bestod av hur det konstruerade gripdonet skulle kunde fatta tag i den stiftade tåten utan att skada tåten eller ändra dess position eller orientering. Genomförandet av laborationen var i enlighet med ``try and fail`` metoden. Laborationen gav riktlinjer avseende på konstruktionen av gripdonet och vilket arbetstryck som är lämpligt för operationen. För högt arbetstryck resulterade i att gripdonet skadade tåten, för lågt arbetstryck resulterade i att friktionskraften mellan tåten och gripdonet blev för låg för att stiftet skulle föras in i kontakten. Andra laborationen bestod av att utröna ett approximativt värde av den robotiserade processens kvalitetsutbyte. I denna laboration utfördes 65 stycken försök till att bilda ett kablage med roboten och antalet godkända noterades. Resultatet från laborationen med de berörda produkterna som används idag vid montering av ett kablage gav kvalitetsutbytet 51%. Företaget som skall eventuellt investera har krav på att kvalitetsutbytet är 95% för att robotisering av processen skall genomföras. En omfattande analys av resultatet från denna laboration ger indikationer på att kravet kan uppnås med vidare produktutveckling av berörda produkter och gripdon.   En ekonomisk analys i form av en pay-off kalkyl ligger som underlag för att bedöma om robotiseringen är ekonomiskt försvarbar, och gav ett approximativt värde för hur mycket förädling av produkten som den robotiserade processen skall ta över från den manuella monteringen. Den förädling som görs av den robotiserade processen kallas i denna förstudie för automatiseringsgrad. Analys av pay-off kalkylen, produkterna samt resultat från laborationerna, anser författaren att robotisering av processen är teknisk möjligt och ekonomiskt försvarbart med de approximativa värdena för automatiseringsgrad på 22 % av den manuella monteringen och med 95% kvalitetsutbyte. / This pilot study investigated the robotization of a process that connects two pined conductors to a plastic contact and thereby forming a cabling. The pilot study examined if the process is technically possible and economically feasible to robotize. Today the pined conductors are attached to the cabling manually. Introduction of robotization is done so that a robot seizes one pined conductor at a time in the pin machine (Schleuniger 67) with a gripper and inserts same into the plastic contact. To determine if the process is technical possible to robotize two experiments were conducted with a gripper that was designed for this purpose. The purpose of the first was to investigate how the gripper could engage the pined conductor without damaging same or change its position or orientation. The experiment was carried out as a “try and fail” type. The experiment resulted in guidelines regarding the design of the gripper and which working pressure was recommendable for the process. A too high pressure could damage the pined conductor and a too low would cause the friction force between the conductor and the gripper to be too low to insert the pined conductor into the plastic contact. The goal of second experiment was to find an approximate value for the quality yield of the process (that is the number of approved cablings in %). In this experiment 65 attempts to form a cabling was performed and the number of approved cablings was checked and documented. The result from the experiment – using the present conductors and plastic components – was a quality approval rate of 51%. The company requires that the quality yield is higher than 95% in order to robotize the process. A thorough analysis of the result of the experiment and discussion with company representatives indicates that the required quality yield can be reached with some further development of the involved components and the gripper making the designs more “automation friendly”. A financial analysis was made using a pay-back calculation in order to determine when and if robotization is financially justified and resulted in an approximate value regarding how much of the value –added in the operation that is to be automated. This value-added that will be performed by the robot is defined as the degree of automation. The conclusion is that robotization (automation) is technically feasible with a degree of automation of 22% and a quality yield of 95%. This is based upon: the pay-back analysis, the present design of the used components and the result from the experiments.
87

Concept and simulation of robotized assembly application

Tullock, Hanna January 2018 (has links)
Assa OEM is a manufacturer of locks and fittings for windows, doors and cabinets. To be more competitive, automating the production is an advantage. Assa assembles six different types of left and right reversible hinges. One product stands for 80 % of the assembly time on the line. For this product Assa wants to implement a robotized assembly solution in one of the three assembly stations. The remaining 20% still needs to be assembled manually. The aim of this study is to investigate three assembly stations, select one assembly station to automate, give three concepts at half-time of the project for the selected assembly station and simulate one final automated concept. The assembly line produces approximately 2000 reversible hinges each day. For the stations in the assembly line the cycle time is around 16 seconds. In the three assembly stations the assembly tasks are similar, it is the number of rivets or parts that differ. In assembly station three there is one additional task that is not included in the first two assembly stations. In this task the arm is lifted and turned 180 degrees, and then placed over three rivets. This is more complex for a robot to perform and will require more equipment. There are similarities between assembly station one and two and therefore concepts for both stations will be given. Three layout concepts are presented for the first assembly station and for the second assembly station one concept is presented. Also, two concepts of combining assembly station one and two are presented. On April 17th, 2018, a meeting at Assa was held to discuss the different concepts and layouts. The discussion led to the conclusion that a further investigation on implementing a robot will be carried out for the concept in assembly station two. The main result is that the cycle time of 16 seconds is difficult to accomplish. The path must be well planned to achieve this with a collaborative robot. To attain the cycle time the end-effector must be designed so that no tool change will be necessary. The rivet is small and therefore a gripper would have difficulty gripping the rivets. Therefore, other methods such as ferromagnetic or vacuum are recommended. The feeder system of the rivet is suggested to have a vibrating bowl feeder due to the orientation of the rivets. The frames’ feeder system needs to be designed for the purpose in assembly station two. The frame that is to be assembled on to the fixture exposes a risk for an operator if working beside the robot. To minimize the risk area from the frame, relocation of the frame feeder and planning the path differently is suggested. The layout will require safety equipment and the suitable safety equipment depends on the flexibility Assa requires.
88

A Flexible, Low-cost Approach to Slippage Detection using Pyroelectricity

Larsson, Anders Robin January 2020 (has links)
Myoelectric prosthesis on the market today are mostly very expensive and rarely allow the amputee any feedback, leaving the users separated from their own robotic arm. Integrating sensory systems into an arm which needs to be replaced several times during a lifetime may also not be cost efficient. With a sensory system tted in a removable and re-sizeable glove, the sensory system will not require a replacement unless broken. Using a exible, durable, low-cost material, sensitive to both change in pressure and temperature, this may be achieved. Using the pyroelectric properties of thin-film Polyvinylidene Fluoride, a sensor able to detect the incipient of slippage and its initial direction is achieved.
89

Kalibreringsstation : Kalibrering av pallgafflar

Johansson, Mattias, Bengtsson, Ander January 2020 (has links)
The work is about designing a calibration station as an integral component of a company's existing product. The product is a robotic cell that automates the production of pallets. The purpose of the calibration station is to rectify an angular error that occurs on the pallet forks, which is mounted on the robot's tool, whose task is to lift and stack the pallets the robot cell manufactures. The company has theories as to why the angular error occurs and believes that there are a number of factors that influence. The purpose of the calibration station is to be able to calibrate the pallet forks when an angular error occurs and to correct all rotations and translations within an approved tolerance. Methods used to carry out the work are to study the problem and investigate how others have solved similar problems and to gather knowledge in the area of ​​calibration. The calibration station design and sensors are evaluated and discussed to determine which sensor and design will solve the task. Algorithms are programmed to find, calculate and correct angular errors that have occurred. The result of the calibration station that has been designed shows that it works for angular errors less than ten degrees in rotation and for translation in millimeters. After a calibration has been performed on the pallet forks, the result of the calibration falls within the requirements of the tolerances specified in the work. The work concludes with an evaluation of how the calibration station can be developed to perform better. / Arbetet handlar om att konstruera en kalibreringsstation som en ingående komponent i ett företags befintliga produkt. Produkten är en robotcell som automatiserar tillverkningen av pallar. Kalibreringsstationens syfte är att åtgärda ett vinkelfel som uppstår på pallgafflarna, som sitter på robotens verktyg, vars uppgift är att lyfta och stapla de pallar robotcellen tillverkar. Företaget har teorier om varför vinkelfelet uppstår och menar att det är ett flertal faktorer som påverkar. Kalibreringsstationens mål är att kunna kalibrera pallgafflarna när ett vinkelfel uppstår och korrigera alla rotationer och translationer inom en godkänd tolerans. Metoder som används för att genomföra arbetet är att studera problemet och undersöka hur andra har löst liknande problem samt samla kunskap inom området kalibrering. Kalibreringsstationens design samt sensorer utvärderas och diskuteras, för att komma fram till vilken sensor och design som skall lösa uppgiften. Algoritmer programmeras för att hitta, beräkna och korrigera vinkelfel som har uppstått. Resultatet för kalibreringsstationen som har konstruerats visar att den fungerar för vinkelfel mindre än tiotal grader i rotation samt för translation i millimeter. Efter att en kalibrering har utförts på pallgafflarna hamnar resultatet av kalibreringen inom kraven på toleranserna som angivits i arbetet. Arbetet avslutas med en utvärdering hur kalibreringsstationen kan utvecklas för att prestera bättre.
90

Understanding and communicating intentions in human-robot interaction

Morvan, Jérémy January 2015 (has links)
This thesis is about the collaboration and interaction between a robot and a human agent. The goal is to use the robot as a coworker, by implementing the premises of an interaction system that would make the interaction as natural as possible. This involves that the robot has a vision system that allows understanding of the intentions of the human. This thesis work is intended to be part of a larger project aimed at extending the competences of the programmable industrial robot, Baxter, made by Rethink Robotics. Due to the limited vision abilities of this robot, a Kinect camera is added on the top of its head. This thesis covers human gestures recognition through the Kinect data and robot reactions to these gestures through visual feedback and actions.

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