|
|
Use of neural networks for estimation of dynamic variables
Dufek, Martin ; Repka, Martin (referee) ; Zháňal, Lubor (advisor)
The aim of the thesis is to verify the applicability of neural networks to predict vehicle dynamic variables. Some vehicle dynamic variables are difficult to measure or need to be calculated, and measuring such quantities can be very expensive. However, If neural networks could predict values with acceptable error, this would be a more affordable and economical method. Verification was performed by creating two recurrent neural networks to estimate the quantities of directional deviation angle and longitudinal forces on all wheels of the car. The paper describes the steps of network creation from processing the input data to evaluating the network predictions. The results show that neural networks can be used to determine dynamic quantities and replace expensive measurements for some purposes. Finally, important insights gained during the creation of neural networks are formulated that can help with the creation of new networks for the estimation of automotive dynamic quantities, and further possible improvements of the created neural networks are outlined.
|
|
|
Use of photogrammetry in machine parts reconstruction
Raclavský, David ; Straka, Tomáš (referee) ; Repka, Martin (advisor)
This thesis provides a general overview of the various 3D scanner designs and focuses on 3D scanners using the principle of photogrammetry and presents their current representatives on the market. In the practical part, the procedure of constructing a machine component using reverse engineering methods is described, where the scanning process and the creation of a CAD model are presented, followed by a comparison of the result with the original 3D scan.
|
|
|
Creating virtual vehicle traffic scenarios in the CarMaker
Jagnešák, Peter ; Repka, Martin (referee) ; Fojtášek, Jan (advisor)
This master’s thesis focuses on the use of the CarMaker simulation software to create realistic scenarios for virtual vehicle testing, which are important for the development and validation of advanced assistance systems and autonomous vehicles. Additionally, the thesis deals with the integration of the virtual environment with real testing data, which enhances the accuracy and efficiency of simulation tests. The goal is to provide insight into the possibilities and challenges of acquiring data from real sources and their subsequent use in virtual testing using the CarMaker software.
|
|
|
Logging of vehicle's position by a differential GPS with base station
Vala, Matěj ; Repka, Martin (referee) ; Straka, Tomáš (advisor)
The present work deals with the study of GPS, differential GPS and GPS with base station. The research focuses on the functioning, present status and future development of these systems. Further the thesis presents the actual measurement of the vehicle route using different GPS system. Base station, experimental vehicle, ADMA-G-PRO+, RT3000 and conventional GPS devices were used for the route measurement. The measurements were performed with and without correction. The analysis of the measured data was carried out in Matlab software in TeleMatrix, focusing on different parameters for each GPS system. The first analysis evaluates the route measurements using three GPS systems (RT3000, ADMA-G-PRO+ and a conventional GPS device). The results obtained show the effect of signal quality, horizontal speed, number of satellites, vehicle orientation, heading standard deviation and accuracy status during normal driving and during specific runs for the different GPS systems. The second analysis evaluates the RT3000 with and without correction for different manoeuvres. The evaluated results show that the RT3000 with correction provides higher accuracy than the RT3000 without correction. The RT3000 with correction shows a lower standard deviation of heading in the range of 0.210° - 2.228°, confirming its higher accuracy compared to the RT3000 without correction, where the standard deviation of heading ranges from 0.384° - 4.418°.
|
|
|
Utilization of Digital Twins in Automotive
Horuta, Šimon ; Fojtášek, Jan (referee) ; Repka, Martin (advisor)
This bachelor thesis deals with the utilization of digital twins in automotive industry. In the introduction, the concept of a digital twin is defined and then Industry 4.0 technologies used by digital twins are described. Furthermore, several examples of their application in the automotive industry are given. In the practical part, a simulation of a braking maneuver in virtual environment is performed and the functionality of this model is verified by real driving tests. As a result of the practical part, the graphs from the simulation and the real driving are compared.
|
|
|
Analysis of crank and cam shaft position sensor variability
Riečica, Samuel ; Repka, Martin (referee) ; Šebela, Kamil (advisor)
This bachelor thesis deals with the working characteristics of crankshaft and camshaft position sensors used in the power unit to ensure correct injection and ignition of the fuel mixture. Their variability was determined by experimental comparison of sensor characteristics. Search of the types and designs of sensors used was carried out in the first phase. Measuring device, which represented a simplified shaft model for sensing characteristics, was designed and constructed in the next step. The experiment was conducted on a statistical sample of 100 pieces of sensors using the Hall effect. The characteristics of the sensors were recorded and evaluated using an oscilloscope with appropriate digital software. Statistical processing of the measured data was performed at the end of the thesis. The results show that the variability of the crankshaft and camshaft position sensors can have an impact on engine performance characteristics and exhaust emissions produced.
|
|
|
Rear Axle Optimization of SIGMA Sports Car
Repka, Martin ; Hejtmánek, Petr (referee) ; Blaťák, Ondřej (advisor)
This master’s thesis deals with analysis and following optimisation of a Sigma TN sports car suspension. Knowledge of vehicle dynamics and strength of materials was used during the optimisation. Kinematic and force analysis was carried out in software ADAMS Car. A FEM analysis was processed in Ansys Workbench environment. Three design concepts were worked out, in which Topology optimisation also found use.
|
|
|
The concept of electric motors used in vehicles
Polnický, Vít ; Repka, Martin (referee) ; Böhm, Michael (advisor)
This bachelor’s thesis deals with the description of electric drives concepts in current vehicles. In the first part, the basic principle of the electric motor is explained, and different types of electric motors are described in detail. In the next part of the thesis, the electrified vehicles are divided into three groups according to the power share of electric motor for vehicle propulsion. The groups are further subdivided according to the powertrain arrangement in the vehicle, indicating the advantages and disadvantages of each concept. In the third part, specific vehicles from each group are presented and compared in terms of performance, range and price. Finally, the concepts are evaluated and a possible development is outlined.
|
|
|
The Investment Models in an Environment of Financial Markets
Repka, Martin ; MSc, Martin Volko (referee) ; Budík, Jan (advisor)
This thesis focuses on automated trading systems for financial markets trading. It describes theoretical background of financial markets, different technical analysis approaches and theoretical knowledge about automated trading systems. The output of the present paper is a diversified portfolio comprising four different investment models aimed to trading futures contracts of cocoa and gold. The portfolio tested on market data from the first quarter 2013 achieved 46.74% increase on the initial equity. The systems have been designed in Adaptrade Builder software using genetic algorithms and subsequently tested in the MetaTrader trading platform. They have been finally optimized using sensitivity analysis.
|
|
|
Recuperation systems in automotive technology
Běhoun, Lukáš ; Repka, Martin (referee) ; Zháňal, Lubor (advisor)
The aim of this bachelor thesis is to examine the methods of energy recuperation in the automotive technology. The first section explores the historical development of the recuperation systems spanning from the end of the 19th century to the present day. The second section is following with the division of the recuperation systems in accordance with the method of their energy storage and their transmission. This is consecutively supported by three examples of use for each of the systems. The third section offers a comparison of the individual cumulative units. Furthermore, it offers a comparison of all the types of systems used in bus transportation. The fourth section analyses the fuel consumption by a bus without a recuperation system and by an identical bus with the Bosch Rexroth recuperation system. This is supported by calculations. Subsequently, the above systems are scrutinized from an economical point of view. The last part deals with the possible development of recuperation systems in the future.
|
guest ::
RSS feed.