Nonlinear coupling problems between the multiple bodies or between the mooring/riser and the offshore platform are incorporated in the CHARM3D-MultiBody, a fully coupled time domain analysis program for multiple bodies with moorings and risers. The nonlinear spring connection module and the three dimensional beam module are added to appropriately solve the structural connection problem. The nonlinear spring connection module includes the hydro-pneumatic tensioner module with the friction & stick/slip implementation, the tendon/mooring disconnection (breakage/unlatch) module with the tendon down-stroke check, and the contact spring with the initial gap with the friction force implemented. The nonlinear coupling may happen in many places for the offshore floating structures, such as hydro-pneumatic tensioner, tendon of TLP down stroke at the bottom joint, stick-slip phenomena at the tie down of the derrick and most of the fender-to-steel or steel-to-steel contact problem with initial gap during the installation. The mooring/tendon broken and unlatch can be a nonlinear connection problem once the transient mode is taken into account. Nonlinearity of the stiffness and friction characteristics of the tensioner combined with stick-slip behavior of riser keel joint is investigated. The relationship between tensions and strokes for hydro-pneumatic tensioner is based on the ideal gas equation where the isotropic gas constant can be varied to achieve an optimum stroke design based on tensioner stiffness. A transient effect of tendon down-stroke and disconnection on global performance of ETLP for harsh environmental condition is also investigated by incorporating the nonlinear boundary condition of the FE tendon model in CHARM3D. The program is made to be capable of modeling the tendon disconnection both at the top and the bottom connection as well as the down stroke behavior for the pinned bottom joint. The performance of the tie-down clamp of derrick is also investigated by using six degrees of freedom spring model and the three(3) dimensional FE beam model. The coupling of the TLP motion with the reaction force at the tie-down clamp is considered by using exact nonlinear dynamic equations of the motion with the reaction forces modeled with the spring or FE beam model. The method reduces too much conservatism when we design the tie-down system by the conventional method, in which all the environmental forces are combined without the phase lag effect between them. The FE beam model is also applied to the connectors between the semisubmersible and the truss for the pre-service and in-place conditions to be verified with the model test results, which shows good agreements.

The objective of this work is to develop a band saw tensioner from the drafting of the specifications to the testing of the prototype while finding the optimal solutions technologically and financially. This development covers the mechanical design and dimensioning of the entire machine. In this repport every step of the project are covered, the benchmark, the specifications, the design and dimensioning, and finally the financial study.

The master thesis is focused on an evaluation of a preload lost in a tappered joint. The analyzed bolts are preloaded by a hydraulic tensioner. When the tensioner is removed, the joint is established and the preload in bolt is decreased. The analysisis carried out on axisymmetry model of joint in ANSYS Workbench 15, a finite element method is implemented in that software. The evaluation of the preload lost is made for a used range of ratio of clamped length to a nominal diameter of bolt. Geometry and material assumptions are defined. Before preloading of bolts to a desired value the process of stabilization preloading must be done otherwise outlines of the analysis are not applicable. On the base of the outlines of the analysis, the method for analytical computing of the desired pretension is done. The method involves the preload lost, which occurs due to establishment of the joint. The strength assesment of the hydraulic tensioner for bolts M72x4 is done. A 3D model of the tensioner with one plane of symmetry was used. Strength criteria for maximum allowed linear-elastic stress are in accordance with ČSN EN 13 445-3.

The thesis presents the design and analysis of a Twin Tensioner for a Belt-driven Integrated Starter-generator (B-ISG) system. The B-ISG is an emerging hybrid transmission closely resembling conventional serpentine belt drives. Models of the B-ISG system's geometric properties and dynamic and static states are derived and simulated. The objective is to reduce the magnitudes of static tension in the belt for the ISG-driving phase. A literature review of hybrid systems, serpentine belt drive modeling and automotive tensioners is included. A parametric study evaluates tensioner parameters with respect to their impact on static tensions. Design variables are selected from these for an optimization study. The optimization uses a genetic algorithm (GA) and a hybrid GA. Results of the optimization indicate the optimal system contains spans with static tensions that are significantly lower in magnitude than that of the original design. Implications of the research on future work are discussed in closing.

The thesis presents the design and analysis of a Twin Tensioner for a Belt-driven Integrated Starter-generator (B-ISG) system. The B-ISG is an emerging hybrid transmission closely resembling conventional serpentine belt drives. Models of the B-ISG system's geometric properties and dynamic and static states are derived and simulated. The objective is to reduce the magnitudes of static tension in the belt for the ISG-driving phase. A literature review of hybrid systems, serpentine belt drive modeling and automotive tensioners is included. A parametric study evaluates tensioner parameters with respect to their impact on static tensions. Design variables are selected from these for an optimization study. The optimization uses a genetic algorithm (GA) and a hybrid GA. Results of the optimization indicate the optimal system contains spans with static tensions that are significantly lower in magnitude than that of the original design. Implications of the research on future work are discussed in closing.

Die Arbeit befasst sich mit der Simulation von Zweiwellen-Zahnriemengetrieben und deren Vorspannmethoden, insbesondere mit der relativ neuen Methode Spannring (ROLL-RING®). Das Ziel der vorliegenden Arbeit ist es, ein analytisches Simulationsmodell zu entwickeln, mit dem grundlegende Erkenntnisse über das statische und dynamische Verhalten solcher ringgespannten Zahnriemengetriebe gewonnen werden können. Für einen exemplarischen Vergleich der Vorspannmethoden, werden außerdem analytische Simulationsmodelle für Zahnriemengetriebe ohne Spannelement und mit federgespannter Rolle erstellt. Als weiteren Bestandteil der vorliegenden Arbeit wird eine Dimensionierungsvorschrift für ringgespannte Zahnriemengetriebe abgeleitet, bei der sowohl statische als auch dynamische Vorgänge im Getriebe berücksichtigt werden können. Anschließend wird der Einfluss der relevanten Parameter auf das Verhalten des ringgespannten Getriebes untersucht. Alle erstellten Simulationsmodelle werden sowohl experimentell an Versuchsständen als auch mittels FEM-Vergleichsrechnung validiert. Die dafür benötigten Getriebeparameter wurden ebenfalls experimentell ermittelt. Abschließend folgt der exemplarische Vergleich der Vorspannmethoden anhand von drei Simulationsbeispielen und einem experimentellen Vergleich des Wirkungsgrads. / This dissertation deals with the simulation of two-shaft timing belt drive and its pre-tension methods. Special attention is given to the relatively new method tensioning ring (ROLL-RING®). The target of the present work is to develop an analytical simulation model, with this fundamental understanding of the static and dynamic behavior of such ring-tensioned timing belt drives can be gained. For an exemplary comparison of pre-tension methods, analytical simulation models for synchronous belt drive without pre-tension element and with tensioner pulley with spring will be created. As another part of the present work a dimensioning specification for ring-tensioned toothed belt drives was deduced. This specification can be considered in both static and dynamic processes in the transmission. Then, the influence of relevant parameters on the behavior of the ring-tensioned timing belt drives is researched. All created simulation models will vali-date both experimental and FEM using comparative calculation. The parameters re-quired for the transmission were also experimentally determined. Finally, the exemplary comparison of pre-tensioned methods basis of three examples of simulation and an ex-perimental comparison of energy conversion efficiency follow.

When working under water at great depths, or in tough environments, remotely controlled underwater vehicles, so called ROV:s, are a good tool too use. With the help of these robots it is possible to work for longer periods of time and at larger depths then with ordinary divers. Ocean Robotics is a company from Linköping, Sweden, that has over 40 years of experience with ROV:s. They produce several different models for different kind of jobs. The purpose of this project was to develop a concept of a device that keeps the tension constant on the tether that connects the ROV with the operator. The tension needs to be constant when the tether is being rolled in on and out from the winch. The work was executed on behalf of Ocean Robotics and a prerequisite was that it should be possible to integrate the device with the winch system they have today. The work have followed Ulrich and Eppingers method for product development and together with requirements from the contractor several concepts was generated. The concepts were validated in a decision matrix and the concepts with the highest score was modeled in the CAD-program CREO Parametrics. The concepts got further developed and was compared against each other once again. Which generated the final concept. Furthermore a couple of friction tests were executed to find appropriate materials for the construction. The final concept will be mounted on the winch and connected to Ocean Robotics self reversing screw. To measure the tension on the tether a load cell is used and the tether is fed by a rubberized wheel that is driven by an electric motor. To adjust the force around the tether a trapezoidal thread is driven by another electric motor, which adjust the pinch wheels height. The tether goes as a tangent between the two wheels that has a profile that insures that the force goes around the tether.

Die Arbeit befasst sich mit der Simulation von Zweiwellen-Zahnriemengetrieben und deren Vorspannmethoden, insbesondere mit der relativ neuen Methode Spannring (ROLL-RING®). Das Ziel der vorliegenden Arbeit ist es, ein analytisches Simulationsmodell zu entwickeln, mit dem grundlegende Erkenntnisse über das statische und dynamische Verhalten solcher ringgespannten Zahnriemengetriebe gewonnen werden können. Für einen exemplarischen Vergleich der Vorspannmethoden, werden außerdem analytische Simulationsmodelle für Zahnriemengetriebe ohne Spannelement und mit federgespannter Rolle erstellt. Als weiteren Bestandteil der vorliegenden Arbeit wird eine Dimensionierungsvorschrift für ringgespannte Zahnriemengetriebe abgeleitet, bei der sowohl statische als auch dynamische Vorgänge im Getriebe berücksichtigt werden können. Anschließend wird der Einfluss der relevanten Parameter auf das Verhalten des ringgespannten Getriebes untersucht. Alle erstellten Simulationsmodelle werden sowohl experimentell an Versuchsständen als auch mittels FEM-Vergleichsrechnung validiert. Die dafür benötigten Getriebeparameter wurden ebenfalls experimentell ermittelt. Abschließend folgt der exemplarische Vergleich der Vorspannmethoden anhand von drei Simulationsbeispielen und einem experimentellen Vergleich des Wirkungsgrads. / This dissertation deals with the simulation of two-shaft timing belt drive and its pre-tension methods. Special attention is given to the relatively new method tensioning ring (ROLL-RING®). The target of the present work is to develop an analytical simulation model, with this fundamental understanding of the static and dynamic behavior of such ring-tensioned timing belt drives can be gained. For an exemplary comparison of pre-tension methods, analytical simulation models for synchronous belt drive without pre-tension element and with tensioner pulley with spring will be created. As another part of the present work a dimensioning specification for ring-tensioned toothed belt drives was deduced. This specification can be considered in both static and dynamic processes in the transmission. Then, the influence of relevant parameters on the behavior of the ring-tensioned timing belt drives is researched. All created simulation models will vali-date both experimental and FEM using comparative calculation. The parameters re-quired for the transmission were also experimentally determined. Finally, the exemplary comparison of pre-tensioned methods basis of three examples of simulation and an ex-perimental comparison of energy conversion efficiency follow.

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