Assembling of the compliant parts used in aviation industry is a challenging process. Assembly fixtures are quite important tools in this effort and widely used in industry. In fixturing of easily deformable sheet metal parts, besides restraining the rigid body motion of the parts, the possible deformations that may occur during the assembly process and the spring-back effect on the final product need to be taken in to consideration. In order to guarantee a successful assembling, in other words, to obtain the final product within specified tolerances, a systematic approach to the fixture design problem is required. The designer should predict the correlation between the input variations and the final assembly variation, especially, for the complex assemblies. This study proposes a design and analysis approach in fixturing of sheet metal assemblies for helicopter components. The design of an assembly fixture for a particular tail cone has been completed convenient to the existing locating principles. Finite Element Analysis (FEA) has been realized in simulating the assembling process in order to predict the possible variation of the interested feature on a complex assembly due to deformations.

<p>Robotsystem har använts flitigt under de senaste årtiondena för att skapa automationslösningar i ett flertal områden. De flesta nuvarande automationslösningarna är begränsade av att uppgifterna de kan lösa måste vara repetitiva och förutsägbara. En av anledningarna till detta är att dagens robotsystem saknar förmåga att förstå och resonera om omvärlden. På grund av detta har forskare inom robotik och artificiell intelligens försökt att skapa intelligentare maskiner. Trots att stora framsteg har gjorts då det gäller att skapa robotar som kan fungera och interagera i en mänsklig miljö så finns det för nuvarande inget system som kommer i närheten av den mänskliga förmågan att resonera om omvärlden.</p><p>För att förenkla problemet har vissa forskare föreslagit en alternativ lösning till helt självständiga robotar som verkar i mänskliga miljöer. Alternativet är att kombinera människors och maskiners förmågor. Exempelvis så kan en person verka på en avlägsen plats, som kanske inte är tillgänglig för personen i fråga på grund av olika orsaker, genom att använda fjärrstyrning. Vid fjärrstyrning skickar operatören kommandon till en robot som verkar som en förlängning av operatörens egen kropp.</p><p>Segmentering och identifiering av rörelser skapade av en operatör kan användas för att tillhandahålla korrekt assistans vid fjärrstyrning eller samarbete mellan människa och maskin. Assistansen sker ofta inom ramen för virtuella fixturer där eftergivenheten hos fixturen kan justeras under exekveringen för att tillhandahålla ökad prestanda i form av ökad precision och minskad tid för att utföra uppgiften.</p><p>Den här avhandlingen fokuserar på två aspekter av samarbete mellan människa och maskin. Klassificering av en operatörs rörelser till ett på förhand specificerat tillstånd under en manipuleringsuppgift och assistans under manipuleringsuppgiften baserat på virtuella fixturer. Den specifika tillämpningen som behandlas är manipuleringsuppgifter där en mänsklig operatör styr en robotmanipulator i ett fjärrstyrt eller samarbetande system.</p><p>En metod för att följa förloppet av en uppgift medan den utförs genom att använda virtuella fixturer presenteras. Istället för att följa en på förhand specificerad plan så har operatören möjlighet att undvika oväntade hinder och avvika från modellen. För att möjliggöra detta estimeras kontinuerligt sannolikheten att operatören följer en viss trajektorie (deluppgift). Estimatet används sedan för att justera eftergivenheten hos den virtuella fixturen så att ett beslut om hur rörelsen ska fixeras kan tas medan uppgiften utförs.</p><p>En flerlagers dold Markovmodell (eng. layered hidden Markov model) används för att modellera mänskliga färdigheter. En gestemklassificerare som klassificerar en operatörs rörelser till olika grundläggande handlingsprimitiver, eller gestemer, evalueras. Gestemklassificerarna används sedan i en flerlagers dold Markovmodell för att modellera en simulerad fjärrstyrd manipuleringsuppgift. Klassificeringsprestandan utvärderas med avseende på brus, antalet gestemer, typen på den dolda Markovmodellen och antalet tillgängliga träningssekvenser. Den flerlagers dolda Markovmodellen tillämpas sedan på data från en trajektorieföljningsuppgift i 2D och 3D med en robotmanipulator för att ge både kvalitativa och kvantitativa resultat. Resultaten tyder på att den flerlagers dolda Markovmodellen är väl lämpad för att modellera trajektorieföljningsuppgifter och att den flerlagers dolda Markovmodellen är robust med avseende på felklassificeringar i de underliggande gestemklassificerarna.</p> / <p>Robot systems have been used extensively during the last decades to provide automation solutions in a number of areas. The majority of the currently deployed automation systems are limited in that the tasks they can solve are required to be repetitive and predicable. One reason for this is the inability of today’s robot systems to understand and reason about the world. Therefore the robotics and artificial intelligence research communities have made significant research efforts to produce more intelligent machines. Although significant progress has been made towards achieving robots that can interact in a human environment there is currently no system that comes close to achieving the reasoning capabilities of humans.</p><p>In order to reduce the complexity of the problem some researchers have proposed an alternative to creating fully autonomous robots capable of operating in human environments. The proposed alternative is to allow <i>fusion </i>of human and machine capabilities. For example, using teleoperation a human can operate at a remote site, which may not be accessible for the operator for a number of reasons, by issuing commands to a remote agent that will act as an extension of the operator’s body.</p><p>Segmentation and recognition of operator generated motions can be used to provide appropriate assistance during task execution in teleoperative and human-machine collaborative settings. The assistance is usually provided in a virtual fixture framework where the level of compliance can be altered online in order to improve the performance in terms of execution time and overall precision. Acquiring, representing and modeling human skills are key research areas in teleoperation, programming-by-demonstration and human-machine collaborative settings. One of the common approaches is to divide the task that the operator is executing into several sub-tasks in order to provide manageable modeling.</p><p>This thesis is focused on two aspects of human-machine collaborative systems.<i> Classfication </i>of an operator’s motion into a predefined state of a manipulation task and assistance during a manipulation task based on <i>virtual fixtures</i>. The particular applications considered consists of manipulation tasks where a human operator controls a robotic manipulator in a cooperative or teleoperative mode.</p><p>A method for online task tracking using <i>adaptive virtual fixtures</i> is presented. Rather than executing a predefined plan, the operator has the ability to avoid unforeseen obstacles and deviate from the model. To allow this, the probability of following a certain trajectory sub-task) is estimated and used to automatically adjusts the compliance of a virtual fixture, thus providing an online decision of how to fixture the movement.</p><p>A layered hidden Markov model is used to model human skills. A gestem classifier that classifies the operator’s motions into basic action-primitives, or gestemes, is evaluated. The gestem classifiers are then used in a layered hidden Markov model to model a simulated teleoperated task. The classification performance is evaluated with respect to noise, number of gestemes, type of the hidden Markov model and the available number of training sequences. The layered hidden Markov model is applied to data recorded during the execution of a trajectory-tracking task in 2D and 3D with a robotic manipulator in order to give qualitative as well as quantitative results for the proposed approach. The results indicate that the layered hidden Markov model is suitable for modeling teleoperative trajectory-tracking tasks and that the layered hidden Markov model is robust with respect to misclassifications in the underlying gestem classifiers.</p>

Computer-aided fixture planning (CAFP) is an essential part of Computer-aided design and manufacturing (CAD/CAM) integration. Proper fixture planning can dramatically reduce the manufacturing cost, the lead-time, and labor skill requirements in product manufacturing. However, fixture planning is a highly experience-based activity. Due to the extreme diversity and complexity of manufacturing workpieces and processes, there are not many fixture planning tools available for industry applications. Moreover, existing CAFP methods rarely consider integrating fixture environmental factors into fixture planning. Automatic fixture planning using VR can provide a viable way for industries. This thesis develops automated approaches to fixture planning in a virtual environment (VE). It intends to address two important issues: automatic algorithms for fixture planning, and the VE to support high fidelity evaluation of fixture planning. The system consists of three parts including fixture assembly planning, feasibility analysis of assembly tools, and motion planning for fixture loading and unloading. The virtual fixture planning system provides the fixture designer a tool for fixture planning and evaluation. Geometrical algorithms are developed to facilitate the automatic reasoning. A Web-based VE for fixture planning is implemented. The three-dimensional (3D) model visualization enables the fixture simulation and validation effectively to investigate existing problems. Approaches to construct desktop-based large VEs are also investigated. Cell segmentation methods and dynamic loading strategies are investigated to improve the rendering performance. Case studies of virtual building navigation and product assembly simulations are conducted. The developed algorithms can successfully generate the assembly plan, validate the assembly tools, and generate moving paths for fixture design and applications. The VE is intuitive and sufficient to support fixture planning, as well as other virtual design and manufacturing tasks.

Computer-aided fixture planning (CAFP) is an essential part of Computer-aided design and manufacturing (CAD/CAM) integration. Proper fixture planning can dramatically reduce the manufacturing cost, the lead-time, and labor skill requirements in product manufacturing. However, fixture planning is a highly experience-based activity. Due to the extreme diversity and complexity of manufacturing workpieces and processes, there are not many fixture planning tools available for industry applications. Moreover, existing CAFP methods rarely consider integrating fixture environmental factors into fixture planning. Automatic fixture planning using VR can provide a viable way for industries. This thesis develops automated approaches to fixture planning in a virtual environment (VE). It intends to address two important issues: automatic algorithms for fixture planning, and the VE to support high fidelity evaluation of fixture planning. The system consists of three parts including fixture assembly planning, feasibility analysis of assembly tools, and motion planning for fixture loading and unloading. The virtual fixture planning system provides the fixture designer a tool for fixture planning and evaluation. Geometrical algorithms are developed to facilitate the automatic reasoning. A Web-based VE for fixture planning is implemented. The three-dimensional (3D) model visualization enables the fixture simulation and validation effectively to investigate existing problems. Approaches to construct desktop-based large VEs are also investigated. Cell segmentation methods and dynamic loading strategies are investigated to improve the rendering performance. Case studies of virtual building navigation and product assembly simulations are conducted. The developed algorithms can successfully generate the assembly plan, validate the assembly tools, and generate moving paths for fixture design and applications. The VE is intuitive and sufficient to support fixture planning, as well as other virtual design and manufacturing tasks.

El presente trabajo se centra en la confección del fixture de Primera A y del fixture de Primera B del fútbol profesional chileno para su temporada 2009. También se analiza el caso del fixture del Torneo de Apertura 2009 de Argentina. Por su parte, esta tesis tiene por finalidad el ser un aporte en el área de sports scheduling, solucionando los problemas antes mencionados en tiempos prudentes. El modelo de programación entera que se desarrolla para Primera A posee 3272 restricciones y 6426 variables binarias. Un problema de estas características es muy difícil de resolver. En tanto que el de Primera B es un poco más pequeño. Si se intenta dar solución a estos problemas en un computador con 4 GB de memoria RAM y procesador Intel Core 2 Duo 2.20 GHz utilizando GAMS y como solver CPLEX 10.2 no hay solución tras más de 100 horas. La misma situación acontece para el problema del fixture de Argentina. Es por ello que se hace necesario implementar una serie de técnicas y procedimientos que permitan acelerar la obtención de resultados. Los procedimientos implementados en esta tesis permiten obtener soluciones en menos de 5 minutos para Primera A. En tanto que para el problema de Primera B por las particularidades del sistema de torneo existen 3 posibles enfoques de solución. Con uno de los enfoques es imposible obtener soluciones que satisfagan todas las restricciones, con los otros enfoques aquello si es posible, tardándose una de las alternativas desde poco más de 30 minutos a alrededor de 18 horas en arrojar soluciones y la otra obteniéndolas en el orden de los 15 minutos. Por último, el caso argentino se utiliza para validar las técnicas expuestas en este trabajo. Y los resultados que se obtienen para este problema son bastante positivos, lo que permite reafirmar la validez de lo que se expone en esta tesis.

Master thesis is focused on the rationalization of production of the forming segment, which is manufactured by company OMNI-X CZ. Familiarization with the product „forming segment“, with issue of production with possibility improvment. The work is also focused on the preparation of the clamping fixture, which should improve the production conditions. The main point of the work include the calculation of cutting forces, clamping forces of the fixture, verification of safety process with economic evaluation. The aim of this master thesis is to indicate the possible direction of the rationalization of the manufacturing of the shaping segments for OMNI-X CZ.

This master’s thesis defines and closely specifies actual trends in clamping systems for shank tools, especially used for milling and drilling operations. The project describes possibilities of application of clamping systems for shank tools for particular types of machining and briefly defines their principles. Experimental part is focused on material analyse of hydraulic and thermal clamping system. Comparing of clamping systems in term of their technical properties and their initial costs is included in technical and economical conclusion.

The thesis deals with various aspects of the structure - manufacturing solutions fixture in terms of small manufacturing firm. In the thesis are discussed problems which the author of the thesis with small-scale production meets. A substantial part of the thesis is also made by comparation of the production of small series production and large series. Emphasis is placed on efficiency and economy of the entire production process.

This thesis is concerned with the design of Škoda 130 RS rear Semi-Trailing Arm Suspension and fixtures on the body. The main requirement of this thesis is to reduce weight of suspension. It is carried out the kinematic analysis and optimization of the kinematic. The construction part of this thesis provides a design of suspension based on the analysis of forces acting on the car wheel. Last part of the thesis includes of new rear suspension stress analysis.

This thesis project was done at Öhlins Racing AB, one of the world leading manufacturers of suspension equipment for motorcycles and race cars. A big part of that development is to collect and analyse data from tests done on fitted motorcycles and cars. How that is usually done is that a motorcycle is fitted with sensors and sent with a test driver around a track. Some adjustments are done on the suspension and then it's sent out again. This can be a very time-consuming process and the rider habits, weather changes and other uncontrollable effects can have a disrupting effect on the results making the tests practically unrepeatable. To be able to place a motorcycle in a controlled environment is therefore desirable to complement the track tests. Öhlins want to be able to use the shake-rig they already have at their facility in Jönköping for motorcycles as well as cars. It was the goal of this thesis project to take the first steps towards that happening. This report describes the process of designing such a support fixture. The goal of the thesis was to find a way to put a complete motorcycle (with rider) on a two post test-rig. This will require a contraption that prevents the motorcycle from falling off it. A comparative study was made with a simulation model to figure out which one of the concepts drawn up would perform the best. The winning concept was a telescopic swing-arm designed to extend from a mounting point on the motorcycle backwards to a foundation standing on the floor behind the bike. Considerable attention was paid to design a good connection to the motorcycle to which various types and makes of bikes could be mounted. The result was a support fixture made of almost exclusively aluminium with telescopic swing arms and a robust connection module to connect to a motorcycle’s peg-mount. The connection module can account for misalignment issues between the peg-mounts and with the use of washers and spacers it is fully adaptable to almost all sorts of bikes. / Detta examensarbete har utförts på Öhlins Racing AB, en av de världsledande tillverkarna av stötdämpare och hjulupphängningar för motorcyklar och racebilar. En stor del av utvecklingen är uppsamling och analys av testdata. Det utförs genom att man bestyckar en motorcykel med sensorer och skickar ut på en testbana. Sen ändrar man inställningar och upprepar testen. Det kan vara en tidskrävande process samtidigt som förarens vana, väder och andra okontrollerade element har avsevärd effekt på resultaten. Detta gör att tester som dessa är svårt att upprepa i praktiken och därför är det önskvärt att placera motorcykeln i en kontrollerad miljö för att komplementera bantesten. Öhlins vill ha möjlighet att använda skakriggen de har i deras anläggning i Jönköping för motorcyklar såväl som för bilar. Det var utmaningen i det här exjobbet att ta de första stegen åt det målet. Rapporten beskriver konstruktionsprocessen för en sådan fixtur. Målet med detta examensarbete var således att hitta ett lämpligt sätt att fixera en motorcykel och dess förare på en skakrigg. Det kräver en apparat som håller motorcykeln upprätt och inte tillåter att den ramlar av. En komparativ studie utfördes för att utvärdera vilket av framtagna koncept som skulle ge bäst resultat. Det valdes att fortsätta med ett koncept där en teleskopisk arm skulle sträckas bakåt från en kontaktpunkt på motorcykeln till ett fundament monterat på golvet bakom motorcykeln. En stor del av arbetet gick ut på att konstruera ett bra inkopplingssystem till motorcykeln mot vilket många olika varianter av motorcyklar kunde kopplas mot. Resultatet blev en fixtur bestående nästan enbart av aluminium, med teleskopiska armar och ett robust inkopplingssystem, kopplade mot motorcykelns fotpinnfästen. Modulen kan övervinna inriktningsproblem mellan fästen och med avståndsbrickor kan den vara kopplad till nästan alla sorters motorcyklar.