This thesis proposes a method to simulate the dynamics of an autonomous underwater vehicle towing another autonomous underwater vehicle of equivalent size using a marine cable in the vertical and horizontal plane. There is a coupling effect between the two vehicles because the towed vehicle is of equivalent size. This means that the towed vehicle cannot be modeled as just a payload but rather, must incorporate the forces and moments experienced and acting on it. In this work, only AUVs with symmetrical hulls are considered, where the towing AUV is moving at a constant velocity with a set thrust while the towed AUV has no thrust. The rope system is another important component that needs to be modeled correctly because the rope material and type significantly impact the motion of the vehicles. The rope system in this study is modeled using a numerical approach called the lumped mass spring damper method which is easy to understand and computationally inexpensive. The rope model accounts for buoyancy differences in different ropes and permits cable flexibility. This thesis enables us to study the motion of multiple combinations of different ropes and axi-symmetric types of underwater vehicles with any fixed or movable fin configuration. / M.S. / This thesis studies the motion of an autonomous underwater vehicle towing another autonomous underwater vehicle which is a large as it is. The towed vehicle cannot be assumed to be just a mass attached to the towing vehicle. There is an interaction between the two vehicle. The towed vehicle places a force on the towed vehicle and the towed vehicle likewise places a force on the towing vehicle. This interaction needs to be modeled correctly to fully capture the impact of both vehicles and their appendages. Additionally, the rope system poses a huge impact on the two vehicle depending on what type of rope is selected. Multiple factors affect the performance of a rope such as the shape and the elasticity. Some ropes may also be denser due to their material type and are less buoyant than others. These factors are considered in the modeling of the overall system and allows us to study different combinations of ropes and symmetric hulled autonomous underwater vehicles.

The goal of this project was to evaluate the viability of a mass-spring-damper based model for modeling of biological tissue. A method for automatically generating such a model from data taken from 3D medical imaging equipment including both the generation of point masses and an algorithm for generating the spring-damper links between these points is presented. Furthermore, an implementation of a simulation of this model running in real-time by utilizing the parallel computational power of modern GPU hardware through OpenCL is described. This implementation uses the fourth order Runge-Kutta method to improve stability over similar implementations. The difficulty of maintaining stability while still providing rigidness to the simulated tissue is thoroughly discussed. Several observations on the influence of the structure of the model on the consistency of the simulated tissue are also presented. This implementation also includes two manipulation tools, a move tool and a cut tool for interaction with the simulation. From the results, it is clear that the mass-springdamper model is a viable model that is possible to simulate in real-time on modern but commoditized hardware. With further development, this can be of great benefit to areas such as medical visualization and surgical simulation. / Målet med detta projekt var att utvärdera huruvida en modell baserad på massa-fjäderdämpare är meningsfull för att modellera biologisk vävnad. En metod för att automatiskt generera en sådan modell utifrån data tagen från medicinsk 3D-skanningsutrustning presenteras. Denna metod inkluderar både generering av punktmassor samt en algoritm för generering av länkar mellan dessa. Vidare beskrivs en implementation av en simulering av denna modell som körs i realtid genom att utnyttja den parallella beräkningskraften hos modern GPU-hårdvara via OpenCL. Denna implementation använder sig av fjärde ordningens Runge-Kutta-metod för förbättrad stabilitet jämfört med liknande implementationer. Svårigheten att bibehålla stabiliteten samtidigt som den simulerade vävnaden ges tillräcklig styvhet diskuteras genomgående. Flera observationer om modellstrukturens inverkan på den simulerade vävnadens konsistens presenteras också. Denna implementation inkluderar två manipuleringsverktyg, ett flytta-verktyg och ett skärverktyg för att interagera med simuleringen. Resultaten visar tydligt att en modell baserad på massa-fjäder-dämpare är en rimlig modell som är möjlig att simulera i realtid på modern men lättillgänglig hårdvara. Med vidareutveckling kan detta bli betydelsefullt för områden så som medicinsk bildvetenskap och kirurgisk simulering.

Haptic feedback is a growing phenomenon that incorporates the sense of touch through tactile sensations such as vibrations, electrical signals, air pressure, and sound waves or through force feedback, which employs torques and/or forces to replicate the pressure and weight of a simulated object. Utilizing haptic technology establishes a communication bridge between the user and the technical component, enhancing the user's understanding of the technical component's surroundings. This thesis focuses on designing a force feedback haptic device with an impedance control strategy, enabling the imposition of dynamic behavior during simulated robot interactions. Impedance control is a commonly employed approach in haptic devices, utilizing a mass-spring-damper model to vary stiffness, damping, and inertia levels, thereby simulating realistic forces and torques in master-slave interactions.  Initially, a haptic device resembling the shape of a Delta robot was designed using Solidworks, with size and weight distribution serving as the primary design considerations. Subsequently, the device was further represented using a generic robot description format, incorporating the design's joints and links. This representation was then paired with kinematic connections delineating the robot's motion and dynamic matrices to simulate the robot's movement. Alongside the integration of an impedance control strategy, simulations were conducted to emulate robot interactions. These simulations tested the system under various conditions, including scenarios with and without introduced torque disturbances. Including torque disturbances was intended to enhance the simulation's realism and assess the impact of impedance control parameter choices on the system's behavior. In summary, the research concludes how a closed-chain robot, the Delta robot, can be modeled as a haptic device with an impedance control strategy, offering valuable guidance for future research. / Haptisk återkoppling är ett växande fenomen som integreras i allt fler användningsområden. Genom att återskapa känslan av att röra vid eller interagera med föremål, antingen genom att simulera taktila sensationer som vibrationer, elektriska signaler, lufttryck och ljudvågor eller genom att återge kraftåterkoppling till användaren, kan användarens förståelse för tekniska komponenter och deras omgivning öka. Kraftåterkoppling möjliggör imitation av tryck och vikt hos simulaterade objekt, vilket förbättrar realismen i användarupplevelsen. Detta examensarbete har inriktat sig på att designa en haptisk pryl med kraftåterkoppling och en styrmekanism baserad på impedanskontroll. Genom att implementera impedanskontroll kan dynamiska beteenden inkorporeras i systemet genom varierande styrka, dämpning och tröghet. Dessa impedansparametrar möjliggör realistiska simuleringar av kraft och vridmoment i samband med virtuella robotinteraktioner. Först utformades en haptisk pryl som efterliknar formen av en Delta-robot med hjälp av CAD-programmet Solidworks. Här var storlek och viktfördelning primära överväganden i designprocessen. Därefter representerades enheten genom en generisk robotbeskrivning som inkluderade dess leder och länkar. Denna representation kopplades sedan ihop med kinematiska samband som reglerade enhetens rörelse. Tillsammans med integreringen av impedanskontrollstrategin genomfördes simuleringar som efterliknade robotinteraktioner. Dessa simuleringar omfattade olika scenarier, inklusive de med vridmomentsstörningar och de utan. Syftet med att inkludera vridmomentsstörningar var att öka realismen i simuleringen och utvärdera påverkan av valda parametrar för impedanskontrollen på systemets beteende. Sammanfattningsvis har detta arbete resulterat i utformningen av en haptisk pryl med kraftåterkoppling, som efterliknar en Delta-robot. Prylen har modellerats som en trädstruktur, med kinematiska samband som sammanfogar dess ändnoder. Det här arbetet har bidragit till kunskapen om hur realistiska haptiska interaktioner kan skapas och öppnat möjligheter för framtida forskning och utveckling inom detta område.