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In today’s world we see that Embedded Systems forms a major part in the life of a human being. Almost every device today has an electronic chip embedded in it. When it comes to automotive, these electronic devices are multiplying. This has resulted in innovative methods of developing Embedded Systems. Among them, Model Based Development has become very popular and a standard way of developing embedded systems. Now, we can see that most embedded systems, especially the automotive systems, are being developed using Model development tools like Simulink. In the design and development of Driver Assistance System, Model Based Design (MBD) plays an important role from system design and simulation to code generation. Modeling tool Matlab/Simulink is now among the most popular tools. Due to the proprietary nature of Simulink and challenges in requirement elicitation phase the industry is looking towards an open source alternative, such as Scicos. Since, most of the OEMs are still using Simulink, there is a need for interoperability between Simulink and Scicos. The present work proposes metamodels for Simulink and Scicos, and Model transformation using these Metamodels for the inter-operability. In order to develop the model transformation the metamodels for Simulink and Scicos were developed using EMF Ecore. These metamodels conform to OMGs MOF Standards. These metamodels were used in developing the transformation definition using the language QVTo. First a simple model was developed, and transformation rules were applied and verified using it. Then a Simulink subsystem of a cross wind assistance system was subjected to forward transformation. The outputs of the model before transformation and that after transformation were compared. They were found to give the same output as desired. Thus, verifying the transformation definition. An attempt was made to achieve reverse transformation. A subsystem in Scicos was considered for reverse transformation. After subjecting it to transformation, an intermediate model conforming to Simulink metamodel was obtained. This shows that the interoperability between Scicos and Simulink can be achieved.

The YellowCar at the professorship of computer engineering of TU Chemnitz is a demonstration vehicle. The car is equipped with multiple networked Electronic Control Unit (ECU)s. There are regular software and hardware updates. Before introduction of any new update, it is essential to test the behavior of the car. This can be done through simulation. Since the majority of the ECU in YellowCar are AUTOSAR based, several AUTOSAR simulation tools can be used to do so. However non-AUTOSAR ECU applications can still not be simulated in these tools. Moreover simulating with such tools need the whole application to be implemented and also very expensive. Simulink is one of the most powerful tools for the purpose of Model-in-the-Loop (MIL) testing which is a popular strategy in the embedded world. The scope of this Master thesis is analyzing the YellowCar and its architecture to develop a dynamic Simulink architectural model that can be modified and extended to facilitate future updates. The outcome of this thesis is an implementation of a model for the YellowCar which allows both AUTOSAR and non-AUTOSAR ECUs to be simulated as one system. Also the model supports extension by easy addition of new modules like ECU or sensor through a graphical user interface.

Für den Austausch und zur Kopplung von Simulationsmodellen ist die Nutzung herstellerübergreifender Standards wie des Functional Mock-up-Interfaces (FMI) unerlässlich. In diesem Artikel wird eine Methode zum automatisierten Export von Simulationsmodellen aus Simulink in Module nach dem Standard FMI for Co-Simulation vorgestellt. Der automatisierte Export nutzt den Quelltextgenerator von Simulink und passt diesen über Templates für den Target Language Compiler so an, dass der erzeugte Quelltext das Functional Mock-up Interface implementiert. Der Artikel beschreibt die Methode zum Auslesen der Signaldefinitionen inkl. Bezeichner und Typen aus dem Simulink-Modell und die Methode zur Generierung des FMI-Quelltextes.

In today’s world we see that Embedded Systems forms a major part in the life of a human being. Almost every device today has an electronic chip embedded in it. When it comes to automotive, these electronic devices are multiplying. This has resulted in innovative methods of developing Embedded Systems. Among them, Model Based Development has become very popular and a standard way of developing embedded systems. Now, we can see that most embedded systems, especially the automotive systems, are being developed using Model development tools like Simulink. In the design and development of Driver Assistance System, Model Based Design (MBD) plays an important role from system design and simulation to code generation. Modeling tool Matlab/Simulink is now among the most popular tools. Due to the proprietary nature of Simulink and challenges in requirement elicitation phase the industry is looking towards an open source alternative, such as Scicos. Since, most of the OEMs are still using Simulink, there is a need for interoperability between Simulink and Scicos. The present work proposes metamodels for Simulink and Scicos, and Model transformation using these Metamodels for the inter-operability. In order to develop the model transformation the metamodels for Simulink and Scicos were developed using EMF Ecore. These metamodels conform to OMGs MOF Standards. These metamodels were used in developing the transformation definition using the language QVTo. First a simple model was developed, and transformation rules were applied and verified using it. Then a Simulink subsystem of a cross wind assistance system was subjected to forward transformation. The outputs of the model before transformation and that after transformation were compared. They were found to give the same output as desired. Thus, verifying the transformation definition. An attempt was made to achieve reverse transformation. A subsystem in Scicos was considered for reverse transformation. After subjecting it to transformation, an intermediate model conforming to Simulink metamodel was obtained. This shows that the interoperability between Scicos and Simulink can be achieved.

To meet the increasing demand on control precision in industrial forklifts, physical modelling of the lifting system has been combined with parameter estimations from data. A number of different controllers have been evaluated in terms of their ability to achieve a load independent lifting speed. The model and controller performance as well as stability properties were evaluated in simulations, and the most promising controller was implemented on the real system. Especially the electric motor turned out to be difficult to model, and therefore experimental data was used to approximate some parts of it. This, along with some friction parameters that had to be estimated caused a slight loss in model generality. An observer (Extended Kalman filter) was used to estimate the unknown states, including the velocity of the forks. The simulated performance of the MPC controller was slightly better than the PID controller, except for a bigger overshoot when starting from a turned off motor. The PID controller also handles model errors better, because of its integral action. Due to the simplicity in relation to performance, only the PID controller was implemented on the forklift. The model turned out to perform well, but not well enough to estimate the lifting height accurately. The PID controller worked as intended and it could therefore be concluded that a more advanced control algorithm, such as an MPC controller, is not necessary for this system.

<p>Scania är en välkänd tillverkare av tunga lastfordon och bussar. De profilerar sig som det presigefyllda valet med hög teknologinivå. För att kunna leda utvecklingen av nya funktioner och motorer måste många tester av alla system i dessa fordon göras. Till detta används provceller speciellt ordnade för specifika lastbilskomponenter och många av dessa komponenter behöver en yttre kylning under drift varför flera av provcellerna har reglerade kylsystem. Vid uppgradering av kylsystem eller nybyggnation av provceller med kylsystem finns en önskan att kunna simulera och göra tester av kylsystemet innan det faktiska kylsystemet finns på plats, för att säkerställa prestandan innan någon investering görs. Detta examensarbete går ut på att genom att skapa vissa basmodeller för komponenter i kylsystem, möjliggöra simulering av godtyckliga kylsystem för utvärdering av olika reglerstrategier, designer och deras prestanda. Vid framtagning av modellerna användes mestadels fysikalisk modellering men även rent praktiska modeller för att fylla en funktion existerar. Det resulterande modellbiblioteket klarar av att visa dynamiska effekter mycket bra men dess statiska träffsäkerhet är inte lika exakt. Dynamiken är dock det viktiga och svårt att få fram på andra sätt, varför modellbiblioteket kan vara användbart vid bedömningar om reglerstrategier och prestanda.</p> / <p>Scania is a wellknown manufacturer of heavy transport vehicles such as trucks and buses. Their profile is to be the prestigeous choice with a high level of technology. To maintain the leading position in development of new functionality and engines, substantial testing is nessecary. This is accomplished by using testbeds specialized for different components and purposes. Many of these components need external cooling during operation which is why a cooling system is present in a large number of testbeds. When new testbeds are to be constructed or an old cooling system is to be redesigned, there is a desire to be able to simulate and run tests of the cooling system before the actual cooling system is in place, to make sure performance is at a high enough level, before any investment is made. The task in this master thesis is to construct, in a matlab and simulink environment, a set of base models for cooling system components. With this set, arbitrary cooling systems can be constructed and simulated to evaluate different designes, control strategies and performance. Physical modelling was the most common method when constucting the base models though some models have a pure practical function. The resulting model library is able to, when put together to a complete cooling system, show dynamic behaviour correctly but static accuracy is a bit off. When judging a new control strategy, dynamic behaviour is the most important aspect, and also the most difficult to get elsewhere, which is why the model library can still be very useful.</p>

<p>The main goal of this thesis is to create a continuous phase modulated radio system with a recursive least square equalizer. The two tested channel models are typical urban and rural area. The result of the performance of this radio system is displayed in Matlab plots as the bit error rate. Three error rates are displayed; with error correction, without error correction and the rate of received incorrect message bursts. Conclusions are also drawn of the performance of the radio system in kbit/sec of bandwidth when the different channel models are used. The performance is also divided into how the equalizer handles inter symbol interference or a fading channel without inter symbol interference.</p> / <p>I detta examensarbete har ett fasmodulerat radiosystem simulerats, fokusering ligger på kanalutjämnare som är av typen recursive least square (RLS). RLS utjämnaren har testats med två olika gsm kanalmodeler, dels typical urban som simulerar radioförbindelser i stadsmiljö den andra modellen är rural area där sändare och mottagare kan se varandra. Tre olika resultat presenteras; med felrättande koder, utan felrättande koder och mängden icke korrekta datapaket. Slutsatser dras om radiosystemets bandbredd när de olika kanalmodellerna används vid olika brusmängd. Även utjämnarens förmåga att hantera inter-symbol interference och fading utvärderas också.</p>

As the global economy strives towards clean energy in the face of climate change, the automotive industry is researching into improving the efficiency of automobiles. Hybrid vehicle systems were proposed and have demonstrated the capability of reducing fuel consumption while maintaining vehicle performance. Various hybrid vehicles in the form of parallel and series hybrid have been produced by difference vehicle manufacturers. The purpose of this thesis is to create a hybrid vehicle model in MATLAB and ADAMS to demonstrate its fuel economy improvement over a conventional vehicle system. The hybrid vehicle model utilizes the Honda IMA (Integrated Motor Assist) architecture, where the electric motor acts as a supplement to the engine torque. The motor unit also acts as a generator during regenerative braking to recover the otherwise lost kinetic energy. The powertrain components’ power output calculation and the control logic were modeled in MATLAB/Simulink, while the mechanical inertial components were modeled in ADAMS. The model utilizes a driver input simulation, where the driver control module compares the actual and desired speeds, and applies a throttle or a braking percent to the powertrain components, which in turns applies the driving or the braking torque to the wheels. Communication between MATLAB and ADAMS was established by ADAMS/Controls. In order to evaluate the accuracy of the MATLAB/ADAMS hybrid vehicle model, simulation results were compared to the published data of ADVISOR. The West Virginia University 5 Peaks drive cycle was used to compare the two software models. The results obtained from MATLAB/ADAMS and ADVISOR for the engine and motor/generator correlated well. Minor discrepancies existed, but were deemed insignificant. This validates the MATLAB/ADAMS hybrid vehicle model against the published results of ADVISOR. Fuel economy of hybrid and conventional vehicle models were compared using the EPA New York City Cycle (NYCC) and the Highway Fuel Economy Cycle (HWFET). The hybrid vehicle demonstrated 8.9% and 14.3% fuel economy improvement over the conventional vehicle model for the NYCC and HWFET drive cycles, respectively. In addition, the motor consumed 83.6kJ of electrical energy during the assist mode while regenerative braking recovered 105.5kJ of electrical energy during city driving. For the highway drive cycle, the motor consumed 213.6kJ of electrical energy during the assist mode while the regenerative braking recovered 172.0kJ of energy. The MATLAB/ADAMS vehicle model offers a simulation platform that is modular, flexible, and can be conveniently modified to create different types of vehicle models. In addition, the simulation results clearly demonstrated the fuel economy advantage of the hybrid vehicle over the conventional vehicle model. It is recommended that a more sophisticated power management algorithm be implemented in the model to optimize the efficiencies of the engine and the motor/generator. Furthermore, it is suggested that the ADAMS vehicle model be validated against an actual vehicle, in order to fully utilize the multi-body vehicle dynamics capability which ADAMS has to offer.