Implementation and analysis of control circuits in MATLAB/Simulink

Bakalářská práce je zaměřená na porovnávání vlastností nejpoužívanějších typů regulátorů. Toto porovnání je realizováno v programu MATLAB/Simulink na modelu stejnosměrného motoru. Nejprve je v bakalářské práci uveden teoretický popis všech struktur regulátorů, které jsou testovány. Jedná se konkrétně o regulátory PID, PSD, PI-D, PS-D, S-PD, I-PD, PID s filtrací derivační složky a PSD taktéž s touto filtrací. Následně je zde uvedena funkce stejnosměrného motoru a jeho matematický popis. V posledním oddílu teoretické části jsou popsány jednotlivé metody nastavování regulátorů. Na závěr bakalářské práce jsou porovnány jednotlivé struktury regulátorů. Jsou zde uvedené dosažené výsledky. A porovnání jejich chování při regulaci polohy stejnosměrného motoru.The thesis is focused on comparing the characteristics of the most common types of controllers. This comparison is done in MATLAB / Simulink to model the DC motor. First, in the thesis, theoretical description of all structures controllers that are tested. This is specifically the PID controllers, PSD, PI-D, PS-D, S-PD, I-PD, PID filtering of derivative and PSD also with this filtration. Then there is the function given the DC motor and its mathematical description. In the last section of the theoretical part describes the different methods of setting regulators. In conclusion, this thesis compares the structure of individual regulators. There are the results. A comparison of their behavior with position control of DC motor.

Virtual piano using image processing

S vzestupem nových technologií, digitalizace je jedna z cest, jak ušetřit peníze, čas a zároveň zefektivňovat práci. Jedna z možností digitalizace je také převedení hudebních nástrojů do jejich virtuální podoby. V této práci jsem nejprve shrnul současnou podobu aktuálních technik vytvoření virtuálního piana a také virtuálních klávesnic obecně. Popsal jsem techniky rozpoznávání ruky, prstů, gest a také různé přístupy snímacích zařízení. Dále jsem v práci porovnal dva různé přístupy rozpoznávání gest rukou a prstů pro vytvoření virtuálního piana. První přístup je otestován pomocí technik zpracování obrazu z RGB kamery. Druhý přístup je pomocí Leap Motion Controller, což je optický modul pro sledování pohybu rukou. Dále jsem popsal výhody a nedostatky těchto přístupů a experimentálně změřil úspěšnost. Pro rozpoznání pozic prstů a predikci stisku kláves na piánu využívám hluboké konvoluční neuronové síť (CNN), Stereo IR 170 Camera Module od firmy Leap Motion a další knihovny jazyka Python s předtrénovanými modely. Na závěr předkládám software virtuálního piána pomocí jedné ze zmíněných technik. Software umožňuje uložit notový zápis hrané hudby do formátu MIDI.With the rise of new technologies, digitalization is one of the ways how to save money, time and make work more efficient. One of the possible goals of digitalization is conversion of musical instruments into their virtual form. In this work I summarized the state-of-the-art and also provided an analysis of the different approaches about creating virtual piano and virtual keyboards in general. Few techniques how hand and and finger gesture recognition is done nowadays are also described in this work as well as different approaches of several controllers. Further, I compared two different approaches to hand and finger detection in order to create the virtual piano. One way is making virtual piano using only RGB camera. Second way is using Leap Motion Controller, which is an optical hand tracking module that captures movement of your hands. Further, I described advantages and disadvantages of these approaches and experimentally tested the accuracy. In the thesis, in order to recognize finger location and predict tapping on the piano keys I am using deep convolutional neural networks (CNN), Stereo IR 170 Camera Module by Leap Motion and other Python libraries with pretrained models. In the end, I provided a virtual piano software using one of these techniques which is able save output of the piano to a MIDI file

Biologically triggered liberation of sub-micron particles from alginate microcapsules

A new method for triggering the burst liberation of encapsulated sub-micron particles from carrier particles using embedded microorganisms has been developed. Triggering mechanisms such as chemical, light, thermal, or magnetic are known, but man-made particles are not yet able to replicate the concept of “hibernation” found in biological systems in the form of spores or seeds that survive in an inactive state and start to grow only once favourable environmental conditions are encountered. An engineered particle system that mimics this property by embedding viable yeast cells into synthetically made alginate microcapsules is reported in this work. Cell growth and division is used as a trigger mechanism for stimuli-responsive release of the encapsulated content. The hybrid living/artificial capsules were formed by an inkjet printing process and the mechanism of biologically triggered release was shown using fluorescently labelled liposomes

Remotely Controlled Diffusion from Magnetic Liposome Microgels

The reversible, temperature-dependent change in the permeability of a phospholipid bilayer has been used for controlling the diffusion rate of encapsulated molecular payload from liposomes. Liposomes were preloaded with a fluorescent dye and immobilized in calcium alginate hydrogel microparticles that also contained iron oxide nanoparticles. The composite microparticles were produced by a drop-on-demand inkjet method. The ability of iron oxide nanoparticles to locally dissipate heat upon exposure to a radio-frequency (RF) alternating magnetic field was used to control the local temperature and therefore diffusion from the liposomes in a contactless way using an RF coil. Several different release patterns were realized, including repeated on-demand release. The internal structure of the composite alginate–liposome–magnetite microparticles was investigated, and the influence of microparticle concentration on the heating rate was determined. In order to achieve a temperature rise required for the liposome membrane melting, the concentration of alginate beads should be at least 25% of their maximum packing density for the nanoparticle concentration and specific absorption rate used

Shape and spin distributions of asteroid populations from brightness variation estimates and large databases

Context. Many databases on asteroid brightnesses (e.g. ALCDEF, WISE) are potential sources for extensive asteroid shape and spin modelling. Individual lightcurve inversion models require several apparitions and hundreds of data points per target. However, we can analyse the coarse shape and spin distributions over populations of at least thousands of targets even if there are only a few points and one apparition per asteroid. This is done by examining the distribution of the brightness variations observed within the chosen population. Aims. Brightness variation has been proposed as a population-scale rather than individual-target observable in two studies so far. We aim to examine this approach rigorously to establish its theoretical validity, degree of ill-posedness, and practical applicability. Methods. We model the observed brightness variation of a target population by considering its cumulative distribution function (CDF) caused by the joint distribution function of two fundamental shape and spin indicators. These are the shape elongation and the spin latitude of a simple ellipsoidal model. The main advantage of the model is that we can derive analytical basis functions that yield the observed CDF as a function of the shape and spin distribution. The inverse problem can be treated linearly. Even though the inaccuracy of the model is considerable, databases of thousands of targets should yield some information on the distribution. Results. We establish the theoretical soundness and the typical accuracy limits of the approach both analytically and numerically. Using simulations, we derive a practical estimate of the model distribution in the (shape, spin)-plane. We show that databases such as Wide-field Infrared Survey Explorer (WISE) yield coarse but robust estimates of this distribution, and as an example compare various asteroid families with each other.Comment: 16 pages, 21 figures, manuscript accepted in Astronomy & Astrophysics, to be published in section 10. Planets and planetary system