National Repository of Grey Literature 74 records found  beginprevious62 - 71next  jump to record: Search took 0.01 seconds. 
Proposal of Microactuator Based on SMART Material
Hradil, Aleš ; Houška, Pavel (referee) ; Hadaš, Zdeněk (advisor)
The master’s thesis deals with the proposal of microactuator based on SMART material. The thesis opens with the comparison of SMART materials which are suitable for actuator construction from the point of view of a reaction on stimulation in form of deformation. Subsequent part of the thesis is the report theory of piezoelectric effect, it also describes direct and indirect effects and it concerns about the description of piezoelectric materials. The thesis focuses on several principles of piezoactuators and motors. The last part of the thesis includes modeling and simulation of piezoelectric material in program ANSYS 13.0 and dimensioning geometric of actuator with evaluation of impact of parameters on final motion.
Piezomotor control
Robotka, Jan ; Richter, Miloslav (referee) ; Macho, Tomáš (advisor)
This thesis aims to propose and implement a control system for a new type of piezomotor with the action elements of MPA for the purpose of measuring characteristics of this piezomotor needed for its use in practice. At the beginning the text processes theoretical data needed for design the control system. The author describes the principle of piezoelectric effect and deals with issues of piezomotors, which are based on this principle. Primarily theoretical knowledge relating to the piezomotor is processed. He also describes the characteristic of microcontroller C8051F015 based on processor core 8051, which is main element of whole control system. His peripherals, which are used in control system, are described more. One of the main parts of the text is design of analog board, which create sawmill course of voltage on piezocrystals of piezomotor. Images are used for description its individual parts. The circuit is controlled by digital and analog outputs of the microcontroller. Another part of the work is focused on communication between microcontroller and PC, which transmits instructions from user using the serial line. Further options of proposed application are shown and important used software components are described. Equally important is program for the microcontroller, which processes incoming messages from PC and manages its digital and analog outputs. In the next chapter is shown design of piezomotor and implementation of prototype the control system. Conclusion of work is devoted to measurement of piezomotor characteristics that shows resolution dependence on frequency, voltage amplitude and vertical pressure. The outgrowth of project, which is elaborated in this work, is the functional control system for the piezomotor with possibility of control through user application on PC. Obtained characteristics of piezomotor will be used for implementation into practice.
Using of Piezo-material for Energy Harvesting from Vibration
Hanus, Jiří ; Dušek, Daniel (referee) ; Hadaš, Zdeněk (advisor)
Master’s Thesis deals with obtaining electricity from the vibrations of the surrounding environment through piezoelectric vibration generator. To simulation piezoceramics and design mechanical parts of the generator was used simulation program ANSYS 10.0. First, parameters of the designed piezoelectric generator were numerically calculated, and then these values were compared with the real sample. Further work is in the description of material properties of piezo materials.
PiezoLegs motor in medical aplication
Plass, Petr ; Koláčný, Josef (referee) ; Ondrák, Tomáš (advisor)
The Bachelor’s thesis is focused to explain of basic conceptions of piezoelectric motors including principles of piezoelectric effect. It is analysed velocities of movement of PiezoWave motor during loading and he is valued supply voltage of used demo driver. Then it is considered of drive with stepper motor and DC motor, it is compared them with piezoelectric motor and chosen the best alternate for the drive of a pump of the artificial heart. Then it is introduced with working in a program i-Speed 2 to analyzing of shots catch by the high speed video camera and it is given a basic manual to connecting, setting and programming of the drive connected to the EPOS P driving unit.
The behaviour of ferroelectrics in the temperature range
Czanadi, Jindřich ; Polsterová, Helena (referee) ; Rozsívalová, Zdenka (advisor)
The submitted thesis describes characteristics and use of the ferroelectric material which has their utilization in electronics and electro technical industry. The thesis describes behaviour ferroelectrics in temperature range. A suitable workplace was designed and its functionality was verified in selected ferroelectrics samples dependence of temperature of components of complex permittivity.
Microposition control device
Kokeš, Ondřej ; Bajer, Arnošt (referee) ; Kadlec, Jaroslav (advisor)
Presented thesis analyses a function of the particular type of the nanopositioner with aim to suggest and construct an electronic device suitable for control of the nanopositioner slider. In presented material there is a description of the control signals and possibility of their generating in the respect of slider movement accuracy. The main goal of the thesis is to describe electronic units ranging from power supply, control processor unit part to end part that directly joint nanopositioner. There is also programme equipment for microcontroller and computer, communication description, movement measuring and calibration and draft for the close-up of the control loop for additional increase of the movement accuracy.
Surface acoustic wave filter
Tichý, Jakub ; Dědková, Jarmila (referee) ; Raida, Zbyněk (advisor)
The theoretical part of this thesis deals with principles and characteristics of the surface acoustic wave filter. It explained the principle of magnetostriction and piezoelectric effect, which uses a filter. In the practical part in the program Comsol Multiphysics are made three simple models of SAW filter. Some modes are founded and are compared to previously known results. In the next phase of project is further studied using the parametric analysis. In the last phase of project is applied global optimization PSO at admittance characteristic from simple 2D structure. The results are compared with the commercially produced devices.
Piezoceramics Measurements
Fialka, Jiří ; Fidler, Petr (referee) ; Beneš, Petr (advisor)
The master’s thesis deals with the piezoelectric coefficients, the resonance frequency and especially the piezoelectric constants verification. With the assistance of several devices, for instance LCR-meter HIOKI 3532, impedance analyzer Agilent 4294A and LCR-meter Agilent E4980A, the resonance and the anti-resonance frequencies as well as impedance and capacitance of samples are measured. The paper opens with the theory of the piezoelectric phenomenon and the difference between direct and indirect piezoelectric phenomenon, it also describes the basic behaviour of a piezoelectric ceramic element during mechanical straining or applied voltage. Further, the paper concerns the description of various piezoelectric constants and their calculations. Subsequent part of the paper is devoted to the temperature dependence of the main piezoelectric parameters of PZT ceramics. The materials coefficients are delineated as a function of temperature of the piezoelectric charge coefficients dij, relative permittivity r, electromechanical coupling factor kij and frequency constants Ni. One of the chapters also determines the piezoelectric charge constant d33 of PZT ceramics by laser interferometer and compares it with the value measured by resonance methods. The surface displacement was measured by a single-beam interferometer Polytec OFV-5000. The results of measurements of piezoelectric charge coefficients d33 acquired by the first and the second method are identical. The last section of the paper is focused on different methods of experimental studies on the characteristics of heat transfer by diffusing heat through conduction between the silver-plated surface of cylinder made of PZT ceramics. The effect on the resonance and the anti-resonance frequencies is monitored. There after, the real heat, determined by thermo camera and the physical model of heat transfer created in program COMSOL Multiphysics, is analysed.
Microdive with linear piezomotor
Grmela, Petr ; Vrba, Jaromír (referee) ; Koláčný, Josef (advisor)
The goal of this bachelor thesis is desctription of function and structure of piezoeletric motor „piezowawes“, creation his laboratory formation and folowing measuring his static characteristic (feed spead / drawing force). Except experimental conclusions is this thesis aim on theoretical analysis and physical explanation of piezoeletric phenomenon. This analys contains materials and important definition which are delaing with this phenomenon. This thesis also contains basic distribution of each kind of piezomotor and discuss aboat their practical use.
Control unit for automotive parking sensors
Otáhal, Jiří ; Klimeš, David (referee) ; Vejlupek, Josef (advisor)
This thesis focuses on programing a control unit for automotive ultrasonic sensors in Matlab Simulink environment. It designs the schematic of the control unit based on the previous version using Eagle, and realizes this design.

National Repository of Grey Literature : 74 records found   beginprevious62 - 71next  jump to record:
Interested in being notified about new results for this query?
Subscribe to the RSS feed.