This thesis document outlines the development of a multibody dynamics simulation of an actively stabilized multiple-input, multiple-output, coupled, balancing cube and the process of verifying the results by implementing the control algorithm in hardware. A non-linear simulation of the system was created in Simscape and used to develop a Linear Quadratic Gaussian control algorithm. To implement this algorithm in actual hardware, the system was first designed, manufactured, and assembled. The structure of the cube and the reaction wheels were milled from aluminum. DC brushless motors were installed into the mechanical system. In terms of electronics, a processor, orientation sensor, motor drivers, analog to digital converters, and a pulse width modulation board were assembled into the cube. Upon completion, the software to control the cube was developed using Simulink and run on a Raspberry Pi computer within the mechanism.

Legged robots have the potential to be a valuable technology that provides agile and adaptive locomotion over complex terrain. To realize legged locomotion's full abilities a control design must consider the nonlinear piecewise dynamics of the systems. This paper aims to develop a controller for the planar bounding of a quadrupedal robot. The bounding of the quadruped robot is characterized by a simplified hybrid model that consists of two subsystems for stance and flight phases and the switching laws between the two states. An additional model, the Multibody model, with fewer simplifications, is used concurrently to best approximate real-world behavior. The bounding gait (periodic orbit) of the robot is predicted by an optimization method based on the numerical integration of the differential equations of subsystems. To stabilize the gait, a switching controller is applied which can be split into two separate phases: stance-phase and swing-phase control. The stance phase implements reaction force control utilizing a body state feedback controller and a gait stabilizer, while the swing phase deploys position control in conjunction with a trajectory planning algorithm to ensure proper footfall. Numerical simulations are carried out for the system with/without control. The control strategy is further validated by simulations of the Simscape multibody model. The overall simulated controller results are promising and demonstrate stable bounding for four system cycles.

La maîtrise de la gestion thermique du moteur à combustion interne permet de répondre à des problématiques telles que la réduction de la consommation de carburant et des émissions de polluants. Cette gestion peut être réalisée par des systèmes mécatroniques, plus précisément grâce à une vanne électromécanique multivoie, appelée ACT valve (Active Cooling thermo-management valve), permettant de mettre en œuvre une stratégie de gestion thermique lors du contrôle des températures dans différentes branches du circuit de refroidissement du moteur thermique.L’objectif du travail est d’améliorer la robustesse du processus de conception de cette vanne en tenant compte des contraintes fonctionnelles multi-physiques telles que la déformation, l’usure, mais aussi de contraintes de fabrication et de tolérancement géométrique liées au processus d’injection des pièces thermoplastiques. Ces incertitudes doivent être prises en compte dès la phase de la conception pour assurer l'efficacité et la fiabilité de ces vannes jusqu'à la fin de leurs vies.Ces travaux de thèses proposent tout d’abord une nouvelle méthode de conception de ces vannes qui se base sur des modèles numériques multi-physiques permettant à tous les métiers d’avoir une base de données commune. Validés expérimentalement, Ces modèles ont permis de mettre en évidence la sensibilité de certains paramètres géométriques sur le couple développé par l’actionneur de la vanne et de s’assurer de la fiabilité du système par la prédiction de l’usure sur un des éléments clés de l’ACT valve.Bien que l’analyse de sensibilité nous ait permis de comprendre l’influence de certains paramètres sur le système, nous avons proposé une nouvelle technique d’identification des configurations optimales du design de cette vanne en utilisant une méthode d’optimisation méta-heuristique multi-objectifs. Les suggestions de conception offertes par cette méthode permettent de réduire le couple résistant sur l’actionneur de la vanne ainsi que l’encombrement global du système. / The thermal management of the internal combustion engine can solve issues related to fuel consumption reduction and pollutant emissions. This management can be applied using mechatronic systems, more precisely thanks to a multi-way electromechanical valve, called ACT valve (Active Cooling thermo-management valve), that presents a thermal management strategy when controlling temperatures in different branches of the engine cooling circuit.The aim of this work is to improve the robustness of the design process of this valve taking into account the multi-physical functional constraints such as deformation, wear, but also geometrical tolerances constraints related to the thermoplastic parts manufacturing process. These uncertainties must be taken into account in the first steps of the design phase to ensure the effectiveness and reliability of this valve over its lifetime.This work first proposes a new method of designing these valves, which is based on multi-physical modeling, allowing the product designers to have a common database. Experimentally validated, these models made it possible to highlight the sensitivity of certain geometrical parameters on the torque developed by the actuator of the valve and to make sure of the reliability of the system with wear prediction on one of the key elements of ACT valve.Although the sensitivity analysis allowed us to understand the influence of certain parameters on the system, we proposed a new technique for identifying optimal configuration configurations of this valve using a metaheuristic, multi-objective optimization method. The design suggestions offered by this method can reduce the resistive torque on the valve DC-actuator as well as the overall packaging.

A soft quadruped robot is being developed at the Department of Machine Design and Department of Production Engineering at KTH. The legs of the robot consist of four continuum actuators that can achieve complex movements. In order to efficiently develop gaits for the robot, reinforcement learning will be used. The learning process will use data from simulation instead of directly from the real robot to save time and resources. However, it is significantly more computationally expensive to simulate soft robotics than rigid, because the physical laws of flexible materials are inherently complex. Because of this, soft robot simulations tend to be slower which limits their usability for reinforcement learning. This thesis explores simulation modelling options in Matlab Simscape for the soft quadruped robot, that can be used in reinforcement learning. Four simulation models of the soft actuator were implemented in order to be tested and compared. Two actuation methods and two build options were chosen based on the literature study and related works, and were then permuted for the different combinations. The tested combinations are: lumped-parameter method actuated by internal force, flexible beam actuated by internal force, lumped-parameter method actuated by cable/pulley network and flexible beam actuated by cable/pulley network. The four actuators were built and tested separately. Computational time and simulation-to-reality gap were used for evaluating the modeling methods. The results show that the best option when modelling the soft actuator for reinforcement learning in Matlab Simscape is to use the lumped-parameter method in combination with a cable and pulley network. High accuracy level can still be achieved despite not keeping the true number of attachment points between the cable and actuator. The number of pulleys in the model is linearly correlated to the time cost required to simulate the model. / En mjuk fyrbent robot är under utveckling vid institutionen för maskinkonstruktion och institutionen för industriell produktion på KTH. Robotens ben består av fyra kontinuerligt deformerbara ställdon som kan åstadkomma komplexa rörelser. För att effektivt utveckla gångstilar till roboten kommer förstärkt inlärning att användas. Inlärningsprocessen kommer att använda data från simulering istället för från den fysiska roboten för att spara tid och resurser. Det är dock betydligt dyrare beräkningsmässigt att simulera mjuk robotik än styv, eftersom flexibla material är mer komplexa. På grund av detta tenderar simuleringar av mjuka robotar att vara långsammare, vilket begränsar deras användbarhet för förstärkt inlärning. Detta examensarbete utforskar därför alternativ för modellering och simulering av den mjuka fyrbenta roboten i Matlab Simscape, med målet att den ska kunna användas med förstärkt inlärning. Fyra olika simuleringsmodeller av det mjuka ställdonet implementerades för att testas och jämföras. Två aktiveringsmetoder och två konstruktionsalternativ valdes baserat på litteraturstudien och relaterade arbeten, och permuterades sedan till möjliga versioner. De testade versionerna är således: klumpparametermetod som aktiveras av intern kraft, flexibel balk som aktiveras av intern kraft, klumpparametermetod som aktiveras av kabelnätverk och flexibel balk som aktiveras av kabelnätverk. De fyra ställdonen byggdes och testades separat. Beräkningstid och grad av verklighetstrogenhet, användes för att jämföra resultaten av dessa tester. Resultaten visar att det bästa alternativet vid modellering av det mjuka ställdonet för förstärkt inlärning i Matlab Simscape är att använda klumpparametermetoden i kombination med ett kabelnätverk. Hög noggrannhetsnivå kan uppnås trots att man inte bibehåller det verkliga antalet fästpunkter mellan kabeln och ställdonet. Antalet fästpunkter för kabeln i modellen är linjärt korrelerat till den tidskostnad som krävs för att simulera modellen.

This thesis gives different views on the modeling and simulation of physical systems, especially together with embedded systems, forming mechatronic systems. The main considered application domain is automotive. One motivation behind the work is to find suitable representations of physical systems to be used in an architectural description language for automotive embedded systems, EAST-ADL2, which is implemented as a UML2 profile, and uses concepts from both UML and SysML. As a part of the thesis, several languages and tools are investigated, including bond graphs, MATLAB/Simulink, Ptolemy II, Modelica, MATLAB/Simscape and SysML. For SysML, the modeling of continuous-time systems and how it relates to MATLAB/Simulink and Modelica is evaluated. A case study of an electric power assisted steering is modeled to show the differences, the similarities and the usage of the above mentioned languages and tools. To be able to classify the tools and languages, five realization levels were developed: Physical modeling models Constraint models Continuous causal models Discretized models Discretized models with solver and platform implementation By using these realization levels, models, tools and modeling languages can be classified, and transformations between them can be set up and analyzed. As a result, a method to describe the simulation behavior of a MATLAB/Simulink model has been developed using SysML activity diagrams as an approach to achieve integrated system models. Another result is an evaluation of the parametric diagrams of SysML for continuous-time modeling, which shows that they do not enable “physical modeling”, i.e. modeling the topology of the system and getting the underlying equations out of this topology. By including physical ports and physical connectors to SysML internal block diagrams, this could be solved. The comparison also shows many similarities between the languages. The results led to a more detailed investigation on conjugate variables, such as force and velocity, and electric current and voltage, and how these are treated in various languages. The thesis also includes two industrial case studies: one of a twin-screw compressor, and one of a simulation environment for automotive fuel-cell systems. Conclusions are drawn from these models, referring to the realization levels. / QC 20100810

The goal of the study was to evaluate the potential of the V2G system as a solution to peak load leveling and integrating more renewable energy in the microgrid of St. Martine Island. Simulink Simscape software was used to model a microgrid with a V2G system for the small community of the Island. The result of the study shows a V2G system with 100 electric cars could play an important role for peak shaving by supplying up to 0.8 MW of electric power back to the grid during peak hours, where each car contributes 10 kW of electric power. It also demonstrates that the V2G system effectively helps to promote solar power capacity from 1 MW to 2.5 MW, hence increase 23.59% share of solar energy in the total grid energy uses compared with the current microgrid of St. Martine Island. / The electricity that is generated from non-renewable sources causesenvironmental pollution and climate changes. Fossil fuel uses leads to thedepletion of fossil fuel resources as well as global warming. On the other hand, renewable energy sources can be used to produce electricity with very few or no CO2 emissions. So, now governments are focusing on renewable energy production. But solar, wind, and other types of renewable energy sources have intermittency. They are not continuously available due to natural factors that cannot be controlled. So, renewable energy needs to be utilized when it is available, or its intermittency can be overcome by energy storage. All Electric vehicle uses a battery pack of large capacity to power the electric motors. These batteries can be used to store the energy that is generated from renewable sources and use them when needed. Besides, the electric grid must always stay in balance. With the development of variable renewable energy production, the management of this balance has become complex. Vehicle to grid is a technology that enables energy to be pushed back to the grid from the battery of an electric car and helps to manage fluctuations on the electricity grid. It helps to balance the grid by charging the battery when renewableenergy is available and load demand is low, then sending energy back to the grid when load demand is high. However, St. Martine Island is a small Island in Bay of Bengal about 9km south of the mainland of Bangladesh. Nearly 6000 people are living there. Since the island is far away from the mainland, grid connection is almostimpossible in terms of cost and geographic location. St. Martine Island has a very high solar power potential, but very low average wind speed. Currently, the electricity demand is fulfilled by stand-alone diesel generators, PV panels, and wind turbines. The current microgrid gets a high load demand during peak hours which is between 6 pm to 11 pm. During this time grid become fully dependent on diesel generators which leads to fossil fuel uses andenvironmental pollution. Here, the project's key objective is to determine the prospects of V2Gtechnology on St. Martine Island to level the peak load during peak hours, given that St. Martine Island is a low windy island with a high average number of yearly peak sun hours. Another goal is to examine the degree to which the share of solar power can be increased by a V2G system in St. Martine Island. In the project, at first, we have modeled a microgrid using Simulink Simscape software. Simulink Simscape enables modeling of a system by putting direct physical connections between the block diagram. In the microgrid model, there are five main sections, which have been designed by assemblingfundamental components in the schematic. A V2G system has been modeled which consists of 100 electric cars as aprototype. Each car has a battery of 100 kWh capacity. Considering thecondition of St. Martine Island and the objective of the project, we have made some assumptions while modeling the V2G section. The results of the project showed that the V2G system significantly smoothed out the peak load during peak hours. It also demonstrated that charging electric cars during daytime by solar power and sending energy back to the grid during peak hours enables the V2G system to accommodate more renewable solar energy sources in the microgrid of St. Martine Island. Finally, the project evident that the V2G system can be integrated into the microgrid of St. Martine Island to level the peak load and to increase the share of solar energy in the total energy uses of the Island.

The construction sector is responsible for 20% of Greenhouse Gas (GHG) emissions, of whichdiesel-powered construction equipment are large contributors. Currently there are many ongoing Fuel Cell (FC) powered construction equipment projects as it is seen as an attractiveoption to power the futures zero-emission heavy-duty machines. Although an attractivealternative, hydrogen FC has drawbacks such as releasing liquid water and water vapor viathe exhaust as a byproduct which in their working environment can cause a suite of issues. Agap in the literature on the water exhausted is present and therefore this degree project seeksto investigate the amount, and ratio, of liquid water and water vapor released from threetypical construction equipment drive cycles which would allow further investigation onappropriate management. The method used for this degree project was to modify a pre-mademodel in Simulink built with Simscape blocks. The model was modified to represent a FCsystem used in a test-rig by implementing experimental and measured data for design andoperating parameters. Different pressures, temperatures, and cathode inlet RelativeHumidity (RH) were investigated to find their effect on the performance and water in theexhaust. A sensitivity analysis of different unknown parameters was also conducted tounderstand their influence on the results. For the reference case, the results showed that foran articulated hauler, the water in the exhaust was 26% liquid which translates to 8.6 kg for a1-hour drive cycle. The crawler excavator and wheel loader, both had 30-minute drive cyclesand had 1.1 kg liquid water with a liquid water ratio of 7% and 0.7 kg liquid water with aliquid water ratio of 5% in the exhaust respectively. For a full 8-hour workday with twoparallel FCs connected, the articulated hauler liquid water amount is 137.6 kg, the crawlerexcavator 35.2 kg, and the wheel loader 22.4 kg. Overall, it was found the liquid water ratiocould be changed to a large extent with different operating parameters, where thetemperature had the greatest influence. The system and stack efficiencies did not changeconsiderably with different operating parameters, meaning that the total water in the exhaustremained similar for the different respective drive cycles.

A systemic mock circulatory loop plays a pivotal role as the in vitro assessment tool for left heart medical devices. The standard design employed by many research groups dates to the early 1970's, and lacks the acuity needed for the advanced device designs currently being explored. The necessity to update the architecture of this in vitro tool has become apparent as the historical design fails to deliver the performance needed to simulate conditions and events that have been clinically identified as challenges for future device designs. In order to appropriately deliver the testing solution needed, a comprehensive evaluation of the functionality demanded must be understood. The resulting system is a fully automated systemic mock circulatory loop, inclusive of anatomical geometries at critical flow sections, and accompanying software tools to execute precise investigations of cardiac device performance. Delivering this complete testing solution will be achieved through three research aims: (1) Utilization of advanced physical modeling tools to develop a high fidelity computational model of the in vitro system. This model will enable control design of the logic that will govern the in vitro actuators, allow experimental settings to be evaluated prior to execution in the mock circulatory loop, and determination of system settings that replicate clinical patient data. (2) Deployment of a fully automated mock circulatory loop that allows for runtime control of all the settings needed to appropriately construct the conditions of interest. It is essential that the system is able to change set point on the fly; simulation of cardiovascular dynamics and event sequences require this functionality. The robustness of an automated system with incorporated closed loop control logic yields a mock circulatory loop with excellent reproducibility, which is essential for effective device evaluation. (3) Incorporating anatomical geometry at the critical device interfaces; ascending aorta and left atrium. These anatomies represent complex shapes; the flows present in these sections are complex and greatly affect device performance. Increasing the fidelity of the local flow fields at these interfaces delivers a more accurate representation of the device performance in vivo.

The topic of this diploma thesis is mathematical model of electric vehicle. The traction drive consists of Li-Ion battery, free-phase DC/AC converter and permanent magnet synchronous machine. The main goal of the thesis is development of function model and making simulations in SIMULINK/SIMSCAPE program. Work is divided into three main parts. The first part is dedicated to the theoretical description of the main drive components. The second part describes partial subsystems of the model. In the last part is build a complete model of electric vehicle and simulated different driving mode.

Tato diplomová práce se zabývá vývojem autonomního zdroje elektrické energie založeného na MEMS termoelektrickém generátoru. Uvažovaný generátor bude následně použit pro napájení autonomní senzorické jednotky pro letecké aplikace. Systémový pohled na autonomní senzorickou jednotku zahrnuje senzor se zpracováním a přenosem dat, energy harvester (termoelektrický generátor), power management, akumulační prvek a autodiagnostiku. Všechny výše uvedené komponenty jsou v práci podrobně popsány. V úvodu práce je provedena široká rešerše existujících termoelektrických generátorů pro letecké aplikace. Následně jsou popsány základní teoretické poznatky z oblasti DC/DC měničů pro energy harvesting. Zvláštní pozornost je věnována metodám MPPT (Maximum Power Point Tracking). Jako základ pro vývoj napájení autonomní senzorické jednotky bylo provedeno množství simulací za pomoci nástroje MATLAB/Simulink Simscape. Pro identifikaci prametrů modelu posloužilo měření na speciálním přípravku. Praktická implementace teoreticky popsaných problémů je provedena na k tomuto účelu navrženém technologickém demonstrátoru. Závěrem je zhodnocena reálná využitelnost navržené technologie pro finální aplikaci v leteckém průmyslu.