Vibroactive Pad Improvement Using Stack Type Piezoactuator

Previously created vibroactive pad encounters with a problem, i.e. vibrations are not fully descended, since amplitudes of vibroactive pad are lower. In microstructure replication process it causes insufficient flow of fluid, since it is directly dependent on the amplitude of excitation. As a solution for this problem stack type piezoactuator together with vibroactive pad of new construction are proposed. It is known, that stack type piezoactuators are able to reach higher amplitudes, than single piezoceramics can do, thus it is considered as a solution, in order to overcome previously mentioned problem. In this paper new construction of vibroactive pad is presented and numerically analyzed using Comsol Multiphysics 3.5a. software in order to determine its natural frequencies

Numerical investigation of dynamical properties of vibroactive pad during hot imprint process

The operating frequencies of the vibroactive pad used in order to improve the quality of replicas of complex microstructures during the mechanical hot imprint process, are numerically analyzed in this paper. It is known that piezoceramics (and in the same time all construction) change its dynamical properties under the action of mechanical load. It is necessary to investigate dynamical properties of vibroactive pad, in order to improve the quality of replicas when planning more detailed research and development in this field in the future. Experimentally there is no possibility to determine the frequency for the construction to be excited, in order to reach modes of forms, thus modeling of the process was performed. The created mathematical model of vibroactive pad was implemented by FEM using COMSOL Multiphysics software. The vibroactive pad’s numerical analysis was performed with and without the action of mechanical load, as well experimental verification of model was performed (for the validation of the model without load with experimental data)

Numerical Investigation of Dynamical Properties of Vibroactive Pad

The operating frequencies of the vibroactive pad used in order to improve the quality of replicas of complex microstructures during the mechanical hot imprint process, are numerically analyzed in this paper. It is known that piezoceramics changes its dynamical properties under the action of mechanical load. It is necessary to investigate dynamical properties of vibroactive pad, in order to improve the quality of replicas when planning more detailed research and development in this field in the future. Experimentally there is no possibility to determine the natural frequency for the construction to be excited, in order to reach the same modes of forms, thus modeling of the process was performed. The created mathematical model of vibroactive pad was implemented by FEM using COMSOL Multiphysics software

Investigation of dynamic of smart valve using holographic PRISM system

The purpose of this work is to find dynamic characteristics of a new smart valve with piezoactuator used in different mechatronic systems, in medicine, alimentary industry, etc. Novelty of this valve is that one of the parts of its control device, i.e. membrane, is comprised of two raster steel disks (each disc has the same number of notches) and the flow is controlled by means of optical interference effect generated between them. With the help of holographic PRISM system we investigated which piezocylinder, segmented or nonsegmented, is better to use in the system of smart valve. Also we represented the original patented scheme of the smart valv

Application of incremental polymeric scales for high precision piezoelectric angular positioning system

A high precision piezoelectric rotational stage with low-cost incremental polymeric scales is proposed and investigated in this work. For avoiding datum plane surface errors caused by application of additional bearings to support the rotational part, the latter one contacts with a stationary piezoelectric disc, which oscillates in travelling wave mode, at three specific points via contacting ring. The resolution of rotation is determined only by geometrical errors of external surface of the piezoelectric disc and can be easily achieved to be in the range of 1 µm. Low-cost polymeric scales are applied to measure angular displacement by means of moiré fringes. Peculiarities of scales fabrication are defined taking into consideration the final accuracy of the device

Development and experimental analysis of piezoelectric optical scanner with implemented periodical microstructure

Piezoelectric optical scanner is developed for multi-coordinate control of optical laser beam by excitation of microstructures. The manufactured microstructure is the periodical structure which was implemented in piezoelectric optical scanner design. Such type of opto-micro-mechanical systems can be used for accurate angular or linear deflection of optical elements in various optomechanical and optoelectronic systems. The operating principle of these devices is based on piezoelectric effect and on conversion of high-frequency multi-dimensional mechanical oscillations of piezoelectric vibration transducers into directional multi-coordinate motion of the optical elements in the measurement chain. The main distinctive feature of such optical piezoelectric scanners is the combination of high micrometer range resolution with a wide range of angular deflections of the scanning elements. The manufacturing process and visualization of the microstructure were presented. The device consists of piezoelectric cylinder and a scanning element with three degrees of freedom. The control model of this device was derived using simulation results of optical scanner by COMSOL Multiphysics software. ESPI digital holographic PRISMA system was used to validate the result of simulation of piezoelectric optical scanner and to test the functionality of piezoelectric optical scanner with implemented microstructure

Simulation of hot imprint process of periodic microstructure using elasto-plastic material model

Hot imprint process for thermoplastic polymers is one of the technologies for manufacturing of micro-fluidic and micro-optical components. It combines both microscale resolution and high throughput. In a hot imprint process a rigid stamp is pressed onto a polymer substrate so that micro-patterns can be replicated. Polycarbonate is one of the most important engineering materials in this process. However, nonlinear relationship between temperature and elasto-plastic behavior of this material has not been very well understood until now. This paper explores the development and application of finite element model for studying of polycarbonate substrate behavior under thermal load in order to evaluate temperature and displacement fields as well as stresses formed during hot imprint process. The model of this process includes heat transfer, structural mechanics as well as contact analysis and supports nonlinear structuralthermal analysis with contact, large deformations, and the use of temperature-dependent elastoplastic material formulation. The thermal loads are applied by means of convective boundary conditions. Simulations were performed with COMSOL Multiphysics software using heat transfer transient and structural plane strain parametric analysis types

Development and experimental analysis of piezoelectric optical scanner with implemented periodical microstructure

Piezoelectric optical scanner is developed for multi-coordinate control of optical laser beam by excitation of microstructures. The manufactured microstructure is the periodical structure which was implemented in piezoelectric optical scanner design. Such type of opto-micro-mechanical systems can be used for accurate angular or linear deflection of optical elements in various optomechanical and optoelectronic systems. The operating principle of these devices is based on piezoelectric effect and on conversion of high-frequency multi-dimensional mechanical oscillations of piezoelectric vibration transducers into directional multi-coordinate motion of the optical elements in the measurement chain. The main distinctive feature of such optical piezoelectric scanners is the combination of high micrometer range resolution with a wide range of angular deflections of the scanning elements. The manufacturing process and visualization of the microstructure were presented. The device consists of piezoelectric cylinder and a scanning element with three degrees of freedom. The control model of this device was derived using simulation results of optical scanner by COMSOL Multiphysics software. ESPI digital holographic PRISMA system was used to validate the result of simulation of piezoelectric optical scanner and to test the functionality of piezoelectric optical scanner with implemented microstructure