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Present day manufacturing assembly relies extensively on a variety of fasteners for the assembly of sub-systems, components and trim. Speed Fastening (SF) is one commonly used non-structural assembly fastening method. The primary limitation of SF is the lack of continuously fed rivets. One path to productivity improvement for SF is the development of a continuously feed tool that would eliminate the non-value added time currently scheduled for reloading in the work cycle. In preparation for the design of a new tool, a proactive ergonomic investigation was carried out to examine differences in muscular effort, upper-body posture, as well as subjective ratings of perceived exertion and discomfort across three different work rates for a simulated SF task conducted in a laboratory setting. The purpose of this investigation was to characterize the ergonomic consequences that an increase in work rate would have on SF operators. Twelve healthy female subjects participated in simulated SF work over four test-sessions. The first test session familiarized subjects with the SF tasks as well as the data collection protocol. Subsequent test days, which were scheduled 24 hours apart, were block randomized to one of three work rates (7, 14 and 21 fasteners/min.) with subjects required to complete 120 minutes of a simulated SF task at both waist and shoulder height using a 50% work to rest duty cycle. The results of this study show significant increases in the amount of muscular activity required to complete the simulated SF, particularly for the 21 fasteners per minute work rate, with increases in peak sEMG amplitudes ranging from 3-12% MVIC. Specifically these increases were most marked in the forearm extensor muscles. In addition, significantly deviated postures were found in upper-limb joint ROM data, particularly when SF work was completed at shoulder height. Overall, based on the increased exposure to risk factors known to be precursors for workplace injury (i.e. repetition and awkward posture), it is inferred that an increase in work rate will put SF operators at an elevated risk of musculoskeletal injury. It is expected that this risk would be even more pronounced for work completed at shoulder height. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2009-09-02 00:01:36.701

This work is an exploration of design possibilities within draping based on a knot. This to show alternative possibilities and expressions through the knot in construction of clothing. The knot serves as a draping tool, has a function in each garment and is also decorative. The result is performed in 7 outfits based on experiments draped on a mannequin or my own body. The experiments are developed mainly through the branching strategy (Jones 1992)achieved with draping sessions in different materials, sizes and placements of the knot. Having the knot as starting point allows alternative expressions in construction of well known garments. It is also suggesting a method of closing a piece of clothing using the garment itself which could be developed further in 2D pattern construction.

Die Auswahl einer zweckmäßigen Verbindungstechnik hat großen Einfluss auf die Kosten für die Herstellung und Wartung von Gütern. Das mechanische Verbinden von Bauteilen mit Schließringbolzen gehört zum umformtechnischen Fügen. Damit werden kostengünstig unlösbare und mechanisch hoch beanspruchbare, punktförmige Verbindungen erzeugt. Die vorliegende Arbeit hatte das Ziel, in umfassender Form den Nachweis zu erbringen, dass mit Schließringbolzensystemen ohne Sollbruchstelle wartungsfreie Verbindungen hergestellt werden können. Diese Wartungsfreiheit bezieht sich auf den Erhalt der mechanischen Eigenschaften der Verbindung und des Korrosionsschutzes bis zur beabsichtigten Grenznutzungsdauer. Aus einer Analyse des Standes der Technik wurde der Forschungsbedarf hinsichtlich der Wartungsfreiheit von Schließringbolzenverbindungen aus mechanischer und korrosiver Sicht abgeleitet. In einem mehrstufigen Prüfprogramm, unterteilt nach Anwendungen im Nutzfahrzeugbau und Stahlbau, wurde nach maschinenbaulichen und stahlbaulichen Konzepten die mechanische Leistungsfähigkeit der Verbindungen untersucht. Die Forschungsergebnisse aus diesem Programm und der Test neu entwickelter Beschichtungssysteme für die Bolzen und die Schließringe bestätigten die Eingangsthese über die Wartungsfreiheit. Metallografische Analysen und FEM Rechnungen ergänzen die Arbeit. Sie ist in sechs Abschnitte unterteilt und enthält 135 Abbildungen, 25 Tabellen, 3 Anlagen. Es wurden 118 Literaturquellen berücksichtigt. Mit der Arbeit steht dem Ingenieur ein umfangreiches Auskunftsmaterial zum Vergleich von Schließringbolzenverbindungen mit anderen Fügeverfahren, besonders jedoch zur Verschraubung zur Verfügung. Die durchgeführten Untersuchungen und Aussagen sollten in zukünftiger Forschung zu einem ganzheitlichen Konzept für die rechnerische Auslegung und Dimensionierung von Schließringbolzenverbindungen nach dem Vorbild der VDI 2230 und der EN 1993 weitergeführt werden.

This research focuses on the development of intelligent fastening tool tracking systems for the automotive industry to identify the fastened bolts. In order to accomplish such a task, the position of the tool tip must be identified because the tool tip position coincides with the head of the fastened bolt while the tool fastens the bolt. The proposed systems utilize an inertial measurement unit (IMU) and another sensor to track the position and orientation of the tool tip. To minimize the position and orientation calculation error, an IMU needs to be calibrated as accurately as possible. This research presents a novel triaxial accelerometer calibration technique that offers a high accuracy. The simulation and experimental results of the accelerometer calibration are presented. To identify the fastening action, an expert system is developed based on the sensor measurements. When a fastening action is identified, the system identifies the fastened bolt by using an expert system based on the position and orientation of the tool tip and the position and orientation of the bolt. Since each fastening procedure needs different accuracies and requirements, three different systems are proposed. The first system utilizes a triaxial magnetometer and an IMU to identify the fastened bolt. This system calculates the position and orientation by using an IMU. An expert system is used to identify the initial position, stationary state, and the fastened bolt. When the tool fastens a bolt, the proposed expert system detects the fastening action by triaxial accelerometer and triaxial magnetometer measurements. When the fastening action is detected, the system corrects the velocity and position error using zero velocity update (ZUPT). By using the corrected tool tip position and orientation, the system can identify the fastened bolts. Then, with the fastened bolt position, the position of the IMU is corrected. When the tool is stationary, the system corrects linear velocity error and reduces the position error. The experimental results demonstrate that the proposed system can identify fastened bolts if the angles of the bolts are different or the bolts are not closely placed. This low cost system does not require a line of sight, but has limited position accuracy. The second system utilizes an intelligent system that incorporates Kalman filters (KFs) and a fuzzy expert system to track the tip of a fastening tool and to identify the fastened bolt. This system employs one IMU and one encoder-based position sensor to determine the orientation and the centre of mass location of the tool. When the KF is used, the orientation error increases over time due to the integration step. Therefore, a fuzzy expert system is developed to correct the tilt angle error and orientation error. When the tool fastens a bolt, the system identifies the fastened bolt by applying the fuzzy expert system. When the fastened bolt is identified, the 3D orientation error of the tool is corrected by using the location and the orientation of the fastened bolt and the position sensor outputs. This orientation correction method results in improved reliability in determining the tool tip location. The fastening tool tracking system was experimentally tested in a lab environment, and the results indicate that such a system can successfully identify the fastened bolts. This system not only has a low computational cost but also provides good position and orientation accuracy. The system can be used for most applications because it provides a high accuracy. The third system presents a novel position/orientation tracking methodology by hybridizing one position sensor and one factory calibrated IMU with the combination of a particle filter (PF) and a KF. In addition, an expert system is used to correct the angular velocity measurement errors. The experimental results indicate that the orientation errors of this method are significantly reduced compared to the orientation errors obtained from an EKF approach. The improved orientation estimation using the proposed method leads to a better position estimation accuracy. The experimental results of this system show that the orientation of the proposed method converges to the correct orientation even when the initial orientation is completely unknown. This new method was applied to the fastening tool tracking system. This system provides good orientation accuracy even when the gyroscopes (gyros hereafter) include a small error. In addition, since the orientation error of this system does not grow over time, the tool tip position drift is limited. This system can be applied to the applications where the bolts are closely placed. The position error comparison results of the second system and the third system are presented in this thesis. The comparison results indicate that the position accuracy of the third system is better than that of the second system because the orientation error does not increase over time. The advantages and limitations of all three systems are compared in this thesis. In addition, possible future work on fastening tool tracking system is described as well as applications that can be expanded by using the KF/PF combination method.

This research focuses on the development of intelligent fastening tool tracking systems for the automotive industry to identify the fastened bolts. In order to accomplish such a task, the position of the tool tip must be identified because the tool tip position coincides with the head of the fastened bolt while the tool fastens the bolt. The proposed systems utilize an inertial measurement unit (IMU) and another sensor to track the position and orientation of the tool tip. To minimize the position and orientation calculation error, an IMU needs to be calibrated as accurately as possible. This research presents a novel triaxial accelerometer calibration technique that offers a high accuracy. The simulation and experimental results of the accelerometer calibration are presented. To identify the fastening action, an expert system is developed based on the sensor measurements. When a fastening action is identified, the system identifies the fastened bolt by using an expert system based on the position and orientation of the tool tip and the position and orientation of the bolt. Since each fastening procedure needs different accuracies and requirements, three different systems are proposed. The first system utilizes a triaxial magnetometer and an IMU to identify the fastened bolt. This system calculates the position and orientation by using an IMU. An expert system is used to identify the initial position, stationary state, and the fastened bolt. When the tool fastens a bolt, the proposed expert system detects the fastening action by triaxial accelerometer and triaxial magnetometer measurements. When the fastening action is detected, the system corrects the velocity and position error using zero velocity update (ZUPT). By using the corrected tool tip position and orientation, the system can identify the fastened bolts. Then, with the fastened bolt position, the position of the IMU is corrected. When the tool is stationary, the system corrects linear velocity error and reduces the position error. The experimental results demonstrate that the proposed system can identify fastened bolts if the angles of the bolts are different or the bolts are not closely placed. This low cost system does not require a line of sight, but has limited position accuracy. The second system utilizes an intelligent system that incorporates Kalman filters (KFs) and a fuzzy expert system to track the tip of a fastening tool and to identify the fastened bolt. This system employs one IMU and one encoder-based position sensor to determine the orientation and the centre of mass location of the tool. When the KF is used, the orientation error increases over time due to the integration step. Therefore, a fuzzy expert system is developed to correct the tilt angle error and orientation error. When the tool fastens a bolt, the system identifies the fastened bolt by applying the fuzzy expert system. When the fastened bolt is identified, the 3D orientation error of the tool is corrected by using the location and the orientation of the fastened bolt and the position sensor outputs. This orientation correction method results in improved reliability in determining the tool tip location. The fastening tool tracking system was experimentally tested in a lab environment, and the results indicate that such a system can successfully identify the fastened bolts. This system not only has a low computational cost but also provides good position and orientation accuracy. The system can be used for most applications because it provides a high accuracy. The third system presents a novel position/orientation tracking methodology by hybridizing one position sensor and one factory calibrated IMU with the combination of a particle filter (PF) and a KF. In addition, an expert system is used to correct the angular velocity measurement errors. The experimental results indicate that the orientation errors of this method are significantly reduced compared to the orientation errors obtained from an EKF approach. The improved orientation estimation using the proposed method leads to a better position estimation accuracy. The experimental results of this system show that the orientation of the proposed method converges to the correct orientation even when the initial orientation is completely unknown. This new method was applied to the fastening tool tracking system. This system provides good orientation accuracy even when the gyroscopes (gyros hereafter) include a small error. In addition, since the orientation error of this system does not grow over time, the tool tip position drift is limited. This system can be applied to the applications where the bolts are closely placed. The position error comparison results of the second system and the third system are presented in this thesis. The comparison results indicate that the position accuracy of the third system is better than that of the second system because the orientation error does not increase over time. The advantages and limitations of all three systems are compared in this thesis. In addition, possible future work on fastening tool tracking system is described as well as applications that can be expanded by using the KF/PF combination method.

Le but principal de cette thèse est de présenter deux contributions dans le domaine desassemblages frettés en prenant en considération les défauts de forme et d’état de surface. Lapremière contribution concerne l’étude de l’influence du défaut de forme sur les caractéristiquesdes assemblages frettés en utilisant une approche basée sur la modélisation par éléments finis.Nous avons constaté que ce défaut a une influence notable sur la résistance de l’assemblage. Destravaux déjà réalisés dans le laboratoire de mécanique de l’université de Bourgogne ont étéconfirmés. Dans la deuxième contribution, nous avons proposé d’intégrer les défauts d’état desurface (rugosité) en créant un élément fini homogénéisé d’interface. Cette technique nous afacilité le maillage de l’interface formés par de macro-éléments traduisant le comportement desaspérités. Ce comportement particulier, dépend de plusieurs paramètres mécaniques etgéométriques qui ont été pris en compte pour définir et identifier numériquement une loid’élasticité isotrope transverse. Cette nouvelle loi a permis de simuler correctement lesassemblages frettés en prenant en compte le défaut d’état de surface. Les résultats obtenus ont étéconfrontés aux expérimentations. En fin, une méthodologie de conception des spécifications dufrettage en considérant le processus d’élaboration des surfaces a été proposée. / The main purpose of this thesis is to present two contributions in the field of shrink fitassembly taking into account the defects of form and roughness surfaces. The first contributionconcerns the study of the influence of the defect forme on the characteristics of shrinked assemblyusing an approach based on finite element modeling. We found that this defect has a significantinfluence on the resistance of the assembly. The work already done in the laboratory of mechanicsat the University of Bourgogne have been confirmed. In the second contribution, we proposed tointegrate the surface defects (roughness) by creating a homogenized finite element interface. Thistechnique has facilitated the mesh of the interface formed by the macro-elements reflecting thebehavior of the asperities. This particular behavior, depends on several mechanical andgeometrical parameters that have been taken into account in defining and identifying a digitallytransverse isotropic elastic law. The new law was used to simulate properly shrinked assembliestaking into account the defect of roughness surface. The results were compared withexperiments. In the end, a design methodology specification by considering the shrinking processof surfaces has been proposed

Friluftskulturen är något som många nordbor håller nära hjärtat. Att ta sig ut i naturen ochutforska lokal så väl som internationell miljö är en form av hållbart resande. Med ett tält breddasdessa möjligheter och längre turer med övernattning får bättre förutsättningar.I ett tält finns många komponenter och delar, varvid två tältdukar, en på insidan och enskyddande duk mot utsidan och omgivningen. Detta projekt tar vid precis mellan innertält ochyttertält och berör kopplingen mellan dessa. Projektet syftar till att utveckla ett nytt fästsystemmellan inner- och yttertält för friluftsföretaget Norrönas nylanserade kupoltält. Utvecklingenav fästsystemet ska bidra till en smidig och lätt hantering. Norrøna är ett norskt företag somutvecklar, producerar och säljer kläder och utrustning för friluftslivet och jobbar just nu med ennyutveckling och lansering av ett kupoltält. Tältet i sig ska möta företagets krav på kvalitet,funktion och design.Projektet har genomförts som ett examensarbete för utbildningsprogrammet Sportteknologi -högskoleingenjör produktutveckling inom huvudområdet maskinteknik vid Mittuniversitetet iÖstersund. Denna rapport omfattar det arbete som gjorts genom produktutvecklingsprocessen,dess ingående faser, metoder och resultat. Processen delades in i fem faser: förstudie,produktspecificering, konceptgenerering, utvärdering och val av koncept, detaljkonstruktionoch prototyp.Resultatet av projektet blev ett välutvecklat koncept som löser huvudproblemet att kopplasamman inner- och yttertält och uppfyller de kriterium som specificerats för produkten.Konceptet är ett system med ett elastiskt band med snitt i dess längsriktning. Bandet sitterfastsytt i innertältets sömmar och har en krok fäst i änden. Kroken förs genom en ögla av textilfastsytt i en förlängning av yttertältets bågkanal och fästes i ett av snitten för att låsa systemet.Lösningen valdes med omtanke och diskussion med Norrøna och presenteras i form av digitalasolidmodeller så väl som prototyp.Projektet och dess resultat överlämnas med goda förutsättningar till att produceras ochappliceras på Norrøna nylanserade kupoltält och bidrar till utvecklingen av friluftskulturen. / The outdoor culture is something that many Scandinavians hold close to their hearts. Gettingout into nature and exploring local as well as international environment is a form of sustainabletravel. With a tent, these opportunities are broadened and longer trips with overnight stays aregiven better conditions.In a tent there are several components, two main tent cloths, one on the inside and one as abarrier against the outside and the surroundings. This project takes place exactly between theinner tent and the outer tent and concerns the connection between them. The project aims todevelop a new fastening system for inner and outer tents at the outdoor company Norrøna'snewly launched dome tent for smooth and easy handling. Norrøna is a Norwegian companythat develops, produces and sells clothes and equipment for outdoor life and currently runninga new development and launch of a dome tent. The tent itself will meet the company'srequirements for quality, function and design.This project is a bachelor thesis for the mechanical engineering program at Mid SwedenUniversity in Östersund. This report begins with the work done through the productdevelopment process, its in-depth phases, methods and results. The process was divided intofive phases: feasibility study, product specification, concept generation, evaluation andselection of concepts, detail design and prototype.The result of the project became a well-developed concept that solves the main problem oflinking inner and outer tents and fulfills the criteria’s that the product had. The concept is asystem with an elastic strap with cuts in its longitudinal direction. The strap is sewn into theseams of the inner tent and has a hook attached to the end. The hook goes through a loop oftextile sewn into an extension of the outer pole canal and is inserted in one of the cuts to lockthe system. The solution was chosen with care and discussion with Norrøna and presenters inthe form of digital solid models as well as prototype.The project and its results are handed over to Norrøna with good circumstances to develop,produce and apply to Norrøna's newly launched dome tent and contributes to development ofthe outdoor culture. / <p>Betyg 2020-07-20</p>

Modern tunnel boring machines require large drilling forces, and need to be fastened in the tunnel to generate such forces. The fastening of tunnel boring machines is traditionally accomplished by means of hydraulic cylinders that fasten and position the machine prior to drilling, known as grippers. A problem encountered in this solution is that the hydraulics suffers from an undesirably low stiffness, which makes the mechanism sensitive to vibrations generated by the drilling. Replacing the hydraulics with some kind of mechanical force transfer mechanismis believed to reduce said sensitivity. The purpose of the thesis is to develop a new gripper concept, evaluate if it is possible to substitute any of the hydraulic actuators with a mechanical counterpart, and assess if a mechanical solution increases the vertical stiffness of the grippers. The CAD-models were created in PRO/Engineer Wildfire 4.0 and the FEM-analysis was conducted using ANSYS Workbench 14.0. The calculations were done using MATLAB R2012a. With an extensive pre-study conducted, a number of gripper concepts were generated and evaluated (using a Pugh´s matrix), and a suggestion of a mechanical force transfer mechanism was created using the information from the concept evaluation. The most suitable force transfer method turned out to be a jack screw mechanism, thanks to its high load carrying capacity and self-locking characteristics. The jack screw will be powered using a hydraulic motor, ashydraulic power is easily accessible on the tunnel boring machine. The analysis conducted points to a significant increase in vertical stiffness, but also to an added degree of complexity which might not be fully desirable. An analysis of the dynamic behavior of the system would also be necessary to fully understand the component interactions. / Moderna tunnelborrningsmaskiner fordrar höga borrkrafter, och behöver fixeras i tunnelgången för att generera dessa. Inspänningen av tunnelborrningsmaskiner görs traditionellt med hydrauliska cylindrar som fixerar och positionerar maskinen inför borrningen, så kallade gripprar. Ett problem med denna metod är att hydrauliken har en viss vekhet som gör konstruktionen känslig för de vibrationer som borrningen skapar, och som eventuellt tros kunna reduceras med en mekanisk lösning. Syftet med detta examensarbete är att ta fram ett nytt gripperkoncept och utreda om det är möjligt att ersätta någon del av hydrauliken med en mekanisk kraftöverföring, för att öka denvertikala styvheten hos mekanismen. CAD-modellerna av koncepten skapades i PRO/EngineerWildfire 4.0 och FEM-analysen gjordes i ANSYS Workbench 14.0. För beräkningarna användes MATLAB R2012a. Med en omfattande förstudie genomförd togs ett antal gripperkoncept fram och utvärderades (med hjälp av Pughs matris), och ett förslag på en mekanisk kraftöverföringsmekanism genererades. Den mest lämpliga kraftöverföringen visade sig vara en skruvdomkraftsanordning,tack vare dess höga lastkapacitet och självhämmande beteende. Mekanismen avses drivas av en hydraulisk motor, då det är en kraftkälla som är lättillgänglig på maskinen. Analysen pekar på att styvheten i konstruktionen kan ökas avsevärt med en mekanisk kraftöverföring, men en sådan tillför också en viss komplexitet till konstruktionen som kanske inte är önskvärd. En analys av det dynamiska beteendet hos konstruktionen är också nödvändig för att till fullo kunna förutse mekanismens beteende.