<p>The ducted fan UAV is an unmanned aerial vehicle consisting mainly of a propeller enclosed in a open ended tube. The UAV has the same basic functions as an ordinary helicopter UAV but has several advantages to the same.</p><p>This thesis aims to estimate the performance of the concept of the ducted fan UAV. The company where this thesis has been written, DST Control AB, is currently investigating the economical possibilities to continue the development of this kind of UAV. This thesis shall provide DST Control AB with a theoretical as well as experimental ground for the investigation by estimation the lift capacity, position accuracy and wind tolerance.</p><p>A ducted fan UAV prototype and a mathematical model for that UAV have been developed by DST Control AB and a student project at Linköping University. The model is constructed through pure physical modeling. Several noise sources have been added to better fit the reality. Several experiments have been conducted to validate the model with satisfying results. Experiments to determine the lift capacity of the craft have also been conducted. These experiments showed a slightly smaller lift capacity than the theoretically calculated lift capacity. The wind tolerance has not been tested in experiments because of the lack of available wind tunnels but simulations have given an estimation of this tolerance.</p><p>To estimate the position accuracy, two different control systems have been implemented. The simplest control system is a system consisting of several PID controllers. The system is divided into two separate subsystems connected in cascade. The inner subsystem takes the pitch, roll and yaw angle as inputs and gives the rudder angles as outputs. The outer subsystem takes the inertial position as input and gives roll, pitch and yaw as outputs. Together, the two subsystems can be used to control the entire craft. The inner subsystem has also been replaced with a small LQ Compensator. An LQ Compensator for the entire system is also implemented giving about as good performance as the PID controller and better performance than the PID/LQ combination.</p>

<p>To fulfill todays requirements on emissions from engines, SCANIA has developed an engine with EGR (Exhaust Gas Recirculation) and VGT (Variable Geometry Turbine). This gives two extra control signals to take into consideration. Open loop optimal control is used to investigate how these two actuators should be controlled to minimize emissions and fuel consumption. A cost function, consisting of the errors between the most important variables and their set points, has been used in the minimization. The variables are the torque, the EGR mass fraction, the oxygen/fuel ratio and the pumping losses.</p><p>From studies of the two control signals in different transients in the engine, information of how to control the VGT and EGR in the optimal way is found. The result from the optimal control has been compared with a PID simulation and has showed a better way to control the signals. The mayor reason why the optimal control is better than a PID controller is the ability to use future values from the transients.</p>

<p>Examensarbetet handlar om att ta fram en processmodell för nivåreglering och det innehåller flera utmaningar. Vätskesystemets dynamik och balans måste beaktas likväl som lämpliga reglermetoder samt modellens utseende. I den här rapporten behandlas hela händelseförloppet från initialskedet till en färdig produkt redo att visas för en publik. Läsaren får möjlighet att närmare granska de komponenter som modellen är uppbyggd av, ta del av programmeringsarbetet och de omfattande test av modellen som utförts. Flera teknikområden belyses men fokus riktas särskilt på ABB:s styrsystem AC800M/800xA, fältbussteknik och reglerstrategier. PID-regulatorn har under arbetet spelat en stor roll och reglerstrategier som innefattar bl.a. framkoppling och kaskadkoppling analyseras och diskuteras. För att bedöma skillnader i val av reglermetod används grafer från praktiska försök. Rapportens upplägg med flertalet illustrationer och den genomgripande tekniska dokumentationen hjälper läsaren att förstå modellens funktion och uppbyggnad.</p>

<p>The purpose of this Master Thesis is to improve the driving performance of mine hoists. The work is divided into two parts. The first and main part deals with simulation of the rope elongation that occurs at load changes in the mine hoist. A mathematical load model of the elongation in the ropes at a mine hoist is made for four types of mine hoists. Mass less springs and dampers are used to get the elastic behaviour of the ropes.</p><p>The mathematical model is implemented in Matlab and Simulink for all four hoist types to make load simulations possible. The implementation in the laboratory HoistLab is made by modifying an existing program with the line elongation functionality. It is only done for the tower mounted friction hoist. There are several functions that are modified to make the simulations realistic.</p><p>The task for the second part of this Master Thesis is to do a pilot study to decide if it is worth making further investigations about how the derivative part will improve the drive performances. A PI controller is designed and gives an acceptable rollback as result when the brakes are released. Then the controller model is extended with the derivative part, D-part, which improves the results essentially. It is still too uncertain how sensitive the system will be for noise when using the derivative part, but the performance potential is clear so the recommendation is to make further investigations.</p> / <p>Syftet med detta examensarbete är att förbättra driftegenskaperna för gruvspel. Arbetet är uppdelat i två olika delar. Den första och största delen handlar om simulering av den lintöjning som uppkommer vid lastförändringar i gruvspel. Matematiska modeller för detta är framtagna för fyra olika sorters typer av gruvspel. Elasticiteten i linorna är modellerad genom masslösa fjädrar och dämpare.</p><p>De matematiska sambanden är implementerade i Matlab och som modeller i Simulink för att utföra simuleringar. I HoistLab är modellen realiserad genom att utöka ett befintligt lastsimuleringsprogram med de nya funktionerna för lintöjning. Detta är utfört enbart för den toppmonterade typen av friktionsspel. Ett flertal funktioner fick ändras för att få realistiska simuleringar.</p><p>Den andra delen av examensarbetet går ut på att göra en förstudie kring den deriverande delen i PID-regulatorer och hur den påverkar gruvspelets prestanda. För denna del är en PI-regulator som ger ett acceptabelt resultat av backgången när bromsarna släpps designad. Därefter är modellen utökad med den deriverande delen, D-delen, vilket ger väsentligt bättre resultat. Det är dock osäkert hur bruskänsligt systemet blir när den deriverande delen används men eftersom förbättringspotentialen är tydlig är rekommendationen att göra vidare undersökningar kring D-delen.</p>

For a long time determining the stability issue of characteristic polynomials has played avery important role in Control System Engineering. This thesis addresses the traditionalcontrol issues such as stabilizing a system with any certain controller analyzingcharacteristic polynomial, yet a new perspective to solve them. Particularly, in this thesis,Proportional-Integral-Derivative (PID) controller is considered for a fixed structuredcontroller. This research aims to attain controller gain set satisfying given performancespecifications, not from the exact mathematical model, but from the empirical data of thesystem. Therefore, instead of a characteristic polynomial equation, a speciallyformulated characteristic rational function is investigated for the stability of the systemin order to use only the frequency data of the plant. Because the performance satisfactionis highly focused on, the characteristic rational function for the investigation of thestability is mainly dealt with the complex coefficient polynomial case rather than realone through whole chapters, and the mathematical basis for the complex case is prepared.For the performance specifications, phase margin is considered first since it is avery significant factor to examine the system’s nominal stability extent (nominal performance). Second, satisfying H norm constraints is handled to make a more robustclosed loop feedback control system. Third, we assume undefined, but bounded outsidenoise, exists when estimating the system’s frequency data. While considering theseuncertainties, a robust control system which meets a given phase margin performance, isattained finally (robust performance).In this thesis, the way is explained how the entire PID controller gain setssatisfying the given performances mentioned in the above are obtained. The approachfully makes use of the calculating software e.g. MATLAB® in this research and isdeveloped in a systematically and automatically computational aspect. The result ofsynthesizing PID controller is visualized through the graphic user interface of acomputer.

This report presents a new way of control engineering. Dc motor speed controlled by three controllers PID, pole placement and Fuzzy controller and discusses the advantages and disadvantages of each controller for different conditions under loaded and unloaded scenarios using software Matlab. The brushless series wound Dc motor is very popular in industrial application and control systems because of the high torque density, high efficiency and small size. First suitable equations are developed for DC motor. PID controller is developed and tuned in order to get faster step response. The simulation results of PID controller provide very good results and the controller is further tuned in order to decrease its overshoot error which is common in PID controllers. Further it is purposed that in industrial environment these controllers are better than others controllers as PID controllers are easy to tuned and cheap. Pole placement controller is the best example of control engineering. An addition of integrator reduced the noise disturbances in pole placement controller and this makes it a good choice for industrial applications. The fuzzy controller is introduce with a DC chopper to make the DC motor speed control smooth and almost no steady state error is observed. Another advantage is achieved in fuzzy controller that the simulations of three different controllers are compared and concluded from the results that Fuzzy controller outperforms to PID controller in terms of steady state error and smooth step response. While Pole placement controller have no comparison in terms of controls because designer can change the step response according to nature of control systems, so this controller provide wide range of control over a system. Poles location change the step response in a sense that if poles are near to origin then step response of motor is fast. Finally a GUI of these three controllers are developed which allow the user to select any controller and change its parameters according to the situation.

A common configuration in buses is that the engine is placed in the rear of the bus and that the batteries are placed in thefront of the bus due to optimization of the distribution of the weight. The long wires running between the engine and the batteries together with large power consuming units, such as fans and air condition units, result in voltage drops. The voltage drops contribute to the battery charging voltage level being lower than desired. The aim with this thesis work is to implement a control system that increases the battery voltage level when the voltage drops occur. Measurements are performed on an articulated bus that is in focus throughout the whole thesis work. A model for the electrical circuit of the bus is created and used when investigating the stability of the control system. The control system isimplemented in the bus, where also verification tests are performed. The verification tests confirm that the control system raises the battery charging voltage to the desired level. The increased voltage level makes the batteries reach a higher state of charge in shorter time since the control system provides the batteries with more charge.

The ducted fan UAV is an unmanned aerial vehicle consisting mainly of a propeller enclosed in a open ended tube. The UAV has the same basic functions as an ordinary helicopter UAV but has several advantages to the same. This thesis aims to estimate the performance of the concept of the ducted fan UAV. The company where this thesis has been written, DST Control AB, is currently investigating the economical possibilities to continue the development of this kind of UAV. This thesis shall provide DST Control AB with a theoretical as well as experimental ground for the investigation by estimation the lift capacity, position accuracy and wind tolerance. A ducted fan UAV prototype and a mathematical model for that UAV have been developed by DST Control AB and a student project at Linköping University. The model is constructed through pure physical modeling. Several noise sources have been added to better fit the reality. Several experiments have been conducted to validate the model with satisfying results. Experiments to determine the lift capacity of the craft have also been conducted. These experiments showed a slightly smaller lift capacity than the theoretically calculated lift capacity. The wind tolerance has not been tested in experiments because of the lack of available wind tunnels but simulations have given an estimation of this tolerance. To estimate the position accuracy, two different control systems have been implemented. The simplest control system is a system consisting of several PID controllers. The system is divided into two separate subsystems connected in cascade. The inner subsystem takes the pitch, roll and yaw angle as inputs and gives the rudder angles as outputs. The outer subsystem takes the inertial position as input and gives roll, pitch and yaw as outputs. Together, the two subsystems can be used to control the entire craft. The inner subsystem has also been replaced with a small LQ Compensator. An LQ Compensator for the entire system is also implemented giving about as good performance as the PID controller and better performance than the PID/LQ combination.

To fulfill todays requirements on emissions from engines, SCANIA has developed an engine with EGR (Exhaust Gas Recirculation) and VGT (Variable Geometry Turbine). This gives two extra control signals to take into consideration. Open loop optimal control is used to investigate how these two actuators should be controlled to minimize emissions and fuel consumption. A cost function, consisting of the errors between the most important variables and their set points, has been used in the minimization. The variables are the torque, the EGR mass fraction, the oxygen/fuel ratio and the pumping losses. From studies of the two control signals in different transients in the engine, information of how to control the VGT and EGR in the optimal way is found. The result from the optimal control has been compared with a PID simulation and has showed a better way to control the signals. The mayor reason why the optimal control is better than a PID controller is the ability to use future values from the transients.

Examensarbetet handlar om att ta fram en processmodell för nivåreglering och det innehåller flera utmaningar. Vätskesystemets dynamik och balans måste beaktas likväl som lämpliga reglermetoder samt modellens utseende. I den här rapporten behandlas hela händelseförloppet från initialskedet till en färdig produkt redo att visas för en publik. Läsaren får möjlighet att närmare granska de komponenter som modellen är uppbyggd av, ta del av programmeringsarbetet och de omfattande test av modellen som utförts. Flera teknikområden belyses men fokus riktas särskilt på ABB:s styrsystem AC800M/800xA, fältbussteknik och reglerstrategier. PID-regulatorn har under arbetet spelat en stor roll och reglerstrategier som innefattar bl.a. framkoppling och kaskadkoppling analyseras och diskuteras. För att bedöma skillnader i val av reglermetod används grafer från praktiska försök. Rapportens upplägg med flertalet illustrationer och den genomgripande tekniska dokumentationen hjälper läsaren att förstå modellens funktion och uppbyggnad.