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HCCI Engine Modeling and Control using Conservation Principles

The aim of the thesis is to model engine physics and dynamics and to design controllers based on the physical model. By implementing equations and solving them it's possible to describe the major phenomena in a four stroke engine running in HCCI mode. To describe the cycle-tocycle connection in the model a wall temperature model was introduced. This wall model is used to simulate the engine dy

TrueTime in Scicos

TrueTime is a MATLAB/Simulink-based simulator for real-time control systems that has been developed at the Department of Automatic Control, LTH. The aim of this thesis is to port the TrueTime kernel block to the open-source Scilab/Scicos simulation environment. The original kernel block is a variable-step, discrete S-function written in C++. In this work, the Scicos engine should replace the Simul

Implementation of an Autotunable Decoupling TITO Controller

In the process industry general TITO systems, i.e. systems with two inputs and two outputs, are usually assumed to be two separate systems. If the system is strongly coupled, the performance is generally poor, but usually nothing is done about this since there are no automatic means to improve it. The aim of this master's thesis is to develop a module with a completely automated design procedu

Safe programming Languages for ABB Automation System 800xA

More than 90 % of all computers are embedded in different types of systems, for example mobile phones and industrial robots. Some of these systems are real-time systems; they have to produce their output within certain time constraints. They can also be safety critical; if something goes wrong, there is a risk that a great deal of damage is caused. Industrial Extended Automation System 800xA, deve

Improved Methods for GPS Navigation

This Master's Thesis presents the development of methods for improved GPS navigation on Wayfinder Navigator, a mobile phone based navigation system developed by Wayfinder Systems. Focus has been put on off track detection, i.e. to detect a user diverging from the route given by the navigation system, and how the GPS position is presented to the user by the application. Improving off track dete

Obstacle Avoidance for Mobile Robots

As a part of the RUNES project a robot has been developed and it has as a part of this theses been improved with an obstacle avoidance component. Work has also been done to make room for additional components on the Tmote sky (one of the micro controllers mounted on the robot) such as a power control component developed at KTH. Attempts has also been made to try to enhance the performance of the r

Lab-data Based Process Control—Comparing SPC and Automatic Control

In many process industries samples are taken and analyzed in laboratories to monitor and ensure proper production conditions. If the analysis result is not within specification limits measures are taken to correct errors. It has proved to be hard to take the appropriate measures. The problem description fits into the confines of control theory and the aim is to make a fairly simple solution to a v

Distributed System Control with FlexRay Nodes in Commercial Vehicles

Most vehicles today use some kind of hydraulic brake system in order to stop the vehicle. There are other techniques that will not only decrease the stop length, but also create a more stable vehicle; an example of such system is the Electromechanical braking system. The problem with such a system is that the requirements of data transmission and reliability are different from the system that is u

Utvärdering av latens och jitter för LQG och PID

Digital control theory normally assumes equidistant sampling intervals and a negligible or constant control delay from sampling to actuation, so called input/output latency. However this can seldom be achieved in practice. In the computer tasks interfere with each other through preemption and blocking when waiting for common resources. The execution time for each task may be data-dependant and the

ModeGraph—A Mode-Automata Based Modelica Library for Embedded Control

The ModeGraph library offers improved flexibility of hybrid modelling and incorporates powerful properties of the Mode-Automata semantics. Concepts from Finite State Machines (FSM), Sequential Function Charts (SFC)/Grafcet and Statecharts are efficiently utilised to provide a flexible modelling environment that a broad audience can feel familiar with. Being able to guarantee mutual exclusivity of

Batch-produktion av biologiska ämnen: Teminologi, metoder och verktyg för förbättrad batch-strategi vid Novozymes Biopharma AB

In every kind of industry there is a wish to use the resources available in the best way possible. If this can be achieved, both time and money can be saved and profit will be maximized. The problem is to know in which way this can be done. When is a resource used in an optimal way? This question was in focus when Novozymes Biopharma AB was about to expand their batch production. In order to contr

New Web based HMI portal för Tetra Pak equipment

The topic of this master thesis is the development of a new Web based HMI portal for Tetra Aptiva Aseptic. The aim is an open source code project where the basic idea is examined and partly implemented during this master thesis. Through a new technique, developed by Tetra Pak, clients can subscribe on topics of interest, which can be viewed on any trusted and connected computer within the Tetra Pa

Process Estimation with Relay Feedback Method

Manual tuning of PID controllers can be very time-consuming and that is why automatic tuning was developed. The conventional automatic tuners use a relay instead of controller in a closed loop system to obtain stabile oscillations. The information from a relay experiment is later used to calculate PID control parameters with different tuning rules and there also exist systems that, apart from the

Error Detection in the Active Front Steering System

Parameters to the CUSUM algorithm are calculated with the aid of the statistical properties of the input data and change detection theory. It works on Gaussian sequences but not on the data from the measurements. Also an approach called Local CUSUM, which lets detectors act over different intervals of the input data is presented and turned out to give good results. These approaches are compared to

Control of Heating Chamber on Packaging Machine A1 TFA

On the packaging machine Tetra Pak A1 a heating box is used to sterilize the packaging material. This is done by passing the material through a bath of hydrogen peroxide and then vaporizing the liquid in the heating box. The heating is done by three resistive elements that pass their energy by convection and radiation to the packaging material. Problems occur due to temperature variations on the w

Engine Cooling & Model Verification

The automotive cooling system and thermal control strategy are important in order to reduce the pollution emission, extend the life of the components and reduce the fuel consumption. The scope of this thesis is to achieve a minimum model that works properly and a small library with the necessary components that the model could be made with. This will be the base for a future Engine Cooling library

Modeling and Grey-box Identification of a Robot Manipulator

Modeling and parameter identification of the main three of an idustrial robot of the type ABB IRB 2000 is considered. This Master thesis has been done at the Department of Automatic Control, Lund Institute of Technology working with a real robot located in the Robotics Laboratory. The model has been bult using the simulation software called Dymola (Dynamic Modeling laboratory), and the parameter i

Modelling NOx-Formation in Combustion Processes

As the regulations of pollutant emission is getting more and more strict, models of pollutant formation, as a part of system level models for control design, are needed. In this thesis NOx (nitrogen oxides) formation is modeled. A method is developed to mix equilibrium and non-equilibrium reaction equations to model NOx formation in combustion processes. This algorithm reduces high-index DAE syste

Linear Time Periodic Analysis of Dc-Dc converter

Aim of this thesis is to analyze Dc-Dc converters by using the techniques of Linear Periodic Time varying (LTP) systems to estimate the amount of subharmonics injected in the load. Dc-Dc converters are used to transform a Dc input to a Dc output of different voltage. In this thesis we study in particular the so called "switch mode" converters. In this kind of devices the conversion is ob

Tire-Road Friction Estimation Using Slip-based Observers

In order to improve the security of the vehicles, the car industry focuses more and more on Active Safety. The objective is to introduce embedded electronic control systems to detect dangerous conditions, warn the driver and, in emergency situations, even take actions to avoid crash or at least reduce the violence of the impact. The tire-road friction coefficient which defines the maximum traction