The purpose of this master thesis is to investigate the possibility to refine the control system of turbochargers in petrol engines by introducing turbo speed measurement. This thesis also investigates possible control enhancement from an electric wastegate actuator compared with a traditional pneumatic actuator. During the thesis work the control problem is divided into 3 sub systems: boost pressure controller, turbo speed controller, and electric actuator controller. The design procedure of the controllers follows model-based method in which a simulation model for engine and a simulation model for electric actuator are used. The designed controller is then implemented and evaluated in an engine test cell. The result of the thesis work shows that the electric wastegate actuator is preferred as it delivers consistent actuation speed and accurate positioning which favours model-based design that requires exact wastegate position. Although the purposed controller structure that uses turbo speed measurement cannot yet achieve faster generation of boost pressure by the end of the thesis work, the use of turbo speed sensor as controller feedback still shows potential to enhance the boost controller and ease the controller design, as the turbo speed measurement can reflect the boost pressure faster and is less sensitive to the disturbances in the air flow.

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This thesis is focused influence of external electromagnetic fields to function of speed sensors. In this work is created summary of individual principles speed sensors and possible sources electromagnetic fields.

Intelligent systems with even the bare minimum of sophistication require extensive computational power and complex processing units. At the same time, small insects like flies are adept at visual navigation, target pursuit, motionless hovering flight, and obstacle avoidance. Thus, biology provides engineers with an unconventional approach to solve complicated engineering design problems. Computational models of the neuronal architecture of the insect brain can provide algorithms for the development of software and hardware to accomplish sophisticated visual navigation tasks. In this research, we investigate biologically-inspired collision avoidance models primarily based on visual motion. We first present a comparative analysis of two leading collision avoidance models hypothesized in the insect brain. The models are simulated and mathematically analyzed for collision and non-collision scenarios. Based on this analysis it is proposed that along with the motion information, an estimate of distance from the obstacle is also required to reliably avoid collisions. We present models with tracking capability as solutions to this problem and show that tracking indirectly computes a measure of distance. We present a camera-based implementation of the collision avoidance models with tracking. The camera-based system was tested for collision and non-collision scenarios to verify our simulation claims that tracking improves collision avoidance. Next, we present a direct approach to estimate the distance from an obstacle by utilizing non-directional speed. We describe two simplified non-directional speed estimation models: the non-directional multiplication (ND-M) sensor, and the non-directional summation (ND-S) sensor. We also analyze the mathematical basis of their speed sensitivity. An analog VLSI chip was designed and fabricated to implement these models in silicon. The chip was fabricated in a 0.18 um process and its characterization results are reported here. As future work, the tracking algorithm and the collision avoidance models may be implemented as a sensor chip and used for autonomous navigation by intelligent systems.

The purpose of this study was to investigate the possibility to measure speed of a vehicle usingimage correlation. It was identified that a new solution of measuring the speed of a vehicle, astoday’s solution does not give the True Speed Over Ground, would open up possibilities of highprecision driving applications. It was also the intention to evaluate the performance of theproposed algorithm on a multicore platform. The study was commissioned by HalmstadUniversity.The investigation of image correlation as a method to measure speed of a vehicle was conductedby applying the proposed algorithm on a sequence of images. The result was compared toreference points in the image sequence to confirm the accuracy. The performance of the multicoreplatform was measured by counting the clock cycles it took to perform one measurement cycle ofthe algorithm.It was found out that using image correlation to measure speed has a positional accuracy of closeto a half percent. The results also revealed that one measurement cycle of the algorithm could beperformed in close to half a millisecond and the achieved parallel utilization of the multicoreplatform was close to eighty-seven percent.It was concluded that the algorithm performed well within the limit of acceptance. A conclusionabout the performance was that low execution time of a measurement cycle makes it possible toexecute the algorithm at a frequency of eighteen hundred Hertz. With a frequency that high, incombination with the camera settings proposed in the thesis, the algorithm would be able tomeasure speeds close to one thousand one hundred kilometers per hour.The authors recommend that future work should be focused on investigating the cameraparameters to be able to optimize both the memory and computational requirements of theapplication. It is also recommended to look closer at the algorithm and the possibilities ofdetecting transversal and angular changes as it would open up for other application areas,requiring more than just the speed.

For many decades there has been a need in many industries to measure speed and position of ferrous gears. This is commonly done by converting passing gear teeth from trigger wheels to electrical impulses to calculate speed and angular position. By using Hall effect sensors or Giant Magnetoresistance sensors (GMR), a zero speed detection of gear teeth is possible while at the same time be cheap to produce and durable for harsh environments. A specially designed trigger-wheel (cogwheel created for measurements) with gear teeth in a specific pattern, exact position can be detected by using a dual sensor, even when no earlier information is available. The new design of trigger-wheel also makes this new method more accurate and universal compared to previous solutions. This thesis demonstrates and argues for the advantages of using a dual sensor for speed and angular position detection on gear wheels. Were one sensor do quantitative measurements for pattern detection in the teeth arrangements and the other sensor do qualitative measurements for position detection.

<p>Disertacija istražuje primenu fleksibilne elektronike za<br />kapacitivne senzore ugla i ugaone brzine tipa apsolutnog i<br />inkrementalnog enkodera cilindrične strukture. Razmatraju se dve<br />strukture, apsolutnog i inkrementalnog enkodera. Izvršena je analiza<br />uticaja mehaničkih nesavršenosti na funkciju kapacitivnosti.<br />Razvijena su dva prototipa kapacitivnih senzora za statičko i<br />dinamičko ispitivanje karakteristika senzora. Razvijena je<br />elektronika za obradu senzora inkrementalnog tipa sa<br />autokalibracijom senzora.</p> / <p>In this thesis a research on application of flexible electronics for capacitive<br />angular position and speed sensors, referred to as absolute and incremental<br />encoders, is done. It considers two structures of absolute and incremental<br />encoder type. An analysis of mechanical inaccuracies influence on a<br />capacitance function is conducted. Two prototypes are developed and used<br />for static and dynamic measurements of capacitive sensor&#39;s characteristics.<br />An electronics front-end for a capacitive two channel incremental encoder with<br />auto-calibration is developed.</p>

When developing three-phase drives for Electric Vehicles (EVs), it is essential to verify the controller design. This will help in understanding how fast and accurately the torque of the motor can be controlled. In order to do this, it is always better to test the controller using the software version of the motor or vehicle drivetrain than using actual hardware as it could lead to component damage when replicating extreme physical behavior. In this thesis, plant modelling of Permanent Magnet Synchronous Machine (PMSM) and vehicle drivetrain in MATLAB/Simulink for Model Based Design (MBD) is presented. MBD is an effective method for controller design that, if adopted can lead to cost savings of 25%-30% and time savings of 35%-40% (according to a global study by Altran Technologies, the chair of software and systems engineering and the chair of Information Management of the University of Technology in Munich) [1]. The PMSM plant models take effects like magnetic saturation, cross- coupling, spatial harmonics and temperature into account. Two PMSM models in d-q frame based on flux and inductance principles were implemented. Flux, torque maps from Finite Element Analysis (FEA) and apparent inductance from datasheets were used as inputs to the flux- and inductance-based models, respectively. The FEA of PMSM was done using COMSOL Multiphysics. The PMSM model results were compared with corresponding FEA simulated results for verification. A comparison of these PMSM models with conventional low fidelity models has also been done to highlight the impact of inclusion of temperature and spatial harmonics. These motor models can be combined with an inverter plant model and a controller can be developed for the complete model. Low frequency oscillations of drivetrain in EVs lead to vibrations which can cause discomfort and torsional stresses. In order to control these oscillations, an active oscillation damping controller can be implemented. For implementation of this control, a three-mass mechanical plant model of drivetrain with an ABS (Anti-lock Braking System) wheel speed sensor has been developed in this thesis. Analysis of the model transfer function to obtain the pole zero maps was performed. This was used to observe and verify presence of low frequency oscillations in the drivetrain. In order to include the effects of ABS wheel speed sensor and CAN communication, a model was developed for the sensor. / Testning av regulatorernas inställningar med hänsyn till snabbhet och noggrannhet i momentreglering är avgörande i trefasiga drivsystem för elektriska fordon. Oftast är det bättre att simulera i stället för att utföra experimentella tester där komponenter kan skadas på grund av fysisk stress. Detta kallas för Model Based Design (MBD). MBD är an effektiv metod för utformningen av styrningen som kan leda till kostnadsbesparingar på 25%-30% och tidsbesparingar på 35%-40% enligt en studie från Altran Technologies i samarbete med Tekniska universitet i München, TUM. Detta examensarbete behandlar en modell för en synkronmaskin med permanentmagneter (PMSM) samt en modell för drivlinan utvecklad i Matlab/Simulink för MBD. PMSMs modellen inkluderar magnetisk mättnad och tvärkoppling, MMF övervågor och temperatur. Två PMSM modeller har utvecklats. Den första baseras på magnetiskt flöde som erhålls från finita element beräkningar i COMSOL Multiphysics medan den andra bygger på induktanser givna från datablad. En jämförelse av dessa PMSM-modeller med konventionella low fidelity-modeller har också gjorts för att illustrera påverkan temperaturberoende och MMF övervågor. Modellerna kan kombineras med en växelriktarmodell för att utveckla en hel styrenhet. Lågfrekventa oscillationer i drivlinan leder till vibrationer som kan orsaka vridspänningar och försämra komforten i elfordonet. En aktiv dämpningsregulator kan implementeras för att kontrollera spänningarna men en mekanisk drivlinemodell med tre massor och en ABS (anti-lock braking system) hastighetssensor behövs. Den mekaniska modellen har implementerats och analyserats även beaktande en modell för en CAN kommunikationskanal. Oscillationer med låg frekvens kunde observeras i modellen.