bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Occasional Shear Loading on Fatigue Crack Growth in 7075 Aluminum Alloy
Authors: Makizaki Masahiko , Matsunaga Hisao , Yanase Keiji , Endo Masahiro
Published: March 2013

Effect of occasional mode II loading on subsequent mode I fatigue crack growth behavior was investigated by using a thin-walled tube made of 7075-T6511 aluminum alloy. Careful observation of crack growth behavior revealed that the occasional mode II loading has two contradictory effects for crack growth behavior. The first is a retardation effect that is associated with the plastic deformation near crack tip. However, this effect is negligibly small for the crack growth life as a whole. The second is an acceleration effect caused by mode II fatigue crack growth itself. It was found that under relatively high ΔK level, the mode II crack growth was about an order magnitude faster than mode I crack growth. Therefore, to properly evaluate the effect of occasional shear loading in the 7075 alloy, the mode II crack growth should be taken into account.
Reductive Removal of Phosphorus in Silicon Using CaO-CaF2 Slag
Authors: Kawamura Hiroaki , Yanaba Yutaka , Yoshikawa Takeshi , Morita Kazuki
Published: March 2013

In order to verify an alternative metallurgical process of phosphorus removal for solar grade silicon (SOG-Si), slag treatment of metallurgical grade silicon (MG-Si) was conducted followed by acid leaching in the present study. MG-Si containing certain amount of phosphorus and calcium was equilibrated at 1723 and 1773 K with several compositions of the CaO-CaF2 slags and phosphorus in molten silicon was confirmed to be removed into slag phase also by reducing reaction as a form of phosphide ion, P3-, in addition to the phosphate ion, PO43-. These contents were separately determined by a wet chemical analysis method developed by ourselves. Although the distribution ratio of phosphorus could not exceed the highest reported values of 3, subsequent leaching brought about considerably high fraction of P removal. The removal fraction of 95.6% was attained when 5 g of silicon was treated with 10 g of the slag at 1773 K followed by the acid leaching, which would be much higher than that expected by the ordinary oxidizing slag treatment. Although the possibility of reducing dephosphorization by slag treatment was clarified, more effective condition should be pursued by changing slag composition, calcium content of silicon, temperature, etc.
Critical Current Characteristics and Flux Pinning in Fe-Based Pnictide Superconductor
Authors: Ni Bao Rong , Otabe Edmund S. , Kiuchi Masaru , Ma Yan Wei
Published: March 2013

The superconducting Ba1-xKxFe2As2(x = 0.4) single crystals were prepared by the so-called FeAs self-flux method. The critical temperature by ac susceptibility measurement was estimated to be about 36 K. The magnetic field and temperature dependences of critical current densities were investigated by an ac inductive measurement (Campbell’s method). Unlike the phenomenon of co-existence of the global and local critical current densities observed in many polycrystalline Fe-based superconducting pnictides, it was found that only a uniform critical current density (Jc) flows through the whole sample. The value of Jcat 20 K and 1 T was about 5×108A/m2, which is much smaller than the local critical current density observed in polycrystalline samples. This result implies that a dissimilarity of flux pinning mechanism exists between these two kinds of materials. The force-displacement characteristic of fluxoids in sample was investigated. The Labusch parameter was found to increase monotonously with increasing magnetic field, while the interaction distance was proportional to the fluxoid spacing. These results are consistent with the prediction based on a simple flux pinning mechanism.
Critical Current Density and Flux Pinning Properties in Superconducting MgB2 with and without SiC Doping
Authors: Sun Wen Xu , Ni Bao Rong , Matsumoto Akiyoshi , Kumakura Hiroaki
Published: March 2013

It is well known that SiC doping in superconducting MgB2 improves the upper critical magnetic field (Bc2) and the critical current density (Jc) under high magnetic field. However, the relationship between SiC doping and the flux pinning mechanism has not been clarified. In this study, several MgB2 samples with and without SiC doping were prepared by the conventional in situ powder-in-tube method. The critical current densities and the force-displacement characteristics of fluxoids in samples were investigated by an ac inductive measurement (Campbell’s method). The Labusch parameter (αL) and the interaction distance (di) were estimated from the obtained force-displacement profile. It was found that SiC doping enhances the values of αL, but does not change the characteristics of the magnetic field dependence of αL apparently. Namely, αL vs. B3/2 characteristics in the pure samples and SiC doped samples are almost the same. Such a result of αL properties implies that the pinning mechanism in the SiC doped samples could be consistent with the conventional pinning theory. On the other hand, di, which is considered to be proportional to the size of pinning potential, decreases rapidly with increasing magnetic field, especially in the pure samples. For high magnetic field region, the variations of di were deduced to be caused by flux creep. The depth of pinning potential, U0, was estimated by using the values of αL and di. The values of U0 give evidence of that SiC doping can prevent the flux bundles moving to another pinning center under high magnetic field.
The Research of Bubble Adsorption to Purify Silicon in the Al-Si System
Authors: Yu Wen Zhou , Ma Wen Hui , Wei Kui Xian , Ren Yong Sheng , Dai Yong Nian , Morita Kazuki
Published: March 2013

The removal of impurities in the process of refining metallurgical grade Si by metallurgical method has been one of the most important research. In this paper, a bubble adsorption effect was proposed to refine the primary silicon in the Al-Si melt. The experimental results show that the impurities content in the primary silicon is related to the volume of bubble in the alloys, the more bubbles exist in the alloys, the less impurities are detected in the primary silicon, and the least impurities content is 84.23ppmw except for Al compared to 777.47ppmw in metallurgical grade Si.
Influence of Carbon Reinforcements on the Mechanical Properties of Ti Composites via Powder Metallurgy and Hot Extrusion
Authors: Li Shu Feng , Sun Bin , Kondoh Katsuyoshi , Mimoto Takanori , Imai Hisashi
Published: March 2013

Ti metal matrix composites (Ti–MMCs) reinforced by vapor grown carbon nanofiber (VGCF) and graphite particle (Gr) were prepared via powder metallurgy and hot extrusion. Ti with 0~0.4wt% VGCF/Gr mixture powders were consolidated by using spark plasma sintering (SPS) at 800 °C. Hot extrusion was then performed at 1000 °C with an extrusion ratio of 37:1. Microstructures and mechanical properties of the as-extruded Ti composites were investigated. Tensile strength of Ti–VGCF/Gr composites was steadily augmented when additions of VGCF/Gr were increased from 0.1 to 0.4 wt%. YS and UTS were increased 40.2% and 11.4% for Ti–0.4wt%VGCF as compared to pure Ti, while those values were 30.5% and 2.1% for Ti–0.4wt%Gr. The strengthening mechanism including grain refinement, carbon solid solution strengthening and dispersion hardening of TiC/carbon was discussed in detail.
Three-Dimensional Characterization of BaZrO3 Precipitates in Y1-xGdxBa2Cu3O7-y Prepared by TFA-MOD Using STEM-Tomography
Authors: Nishiyama Takeshi , Yamada Kazuhiro , Teranishi Ryo , Kaneko Kenji , Kato Takeharu , Izumi Teruo , Shiohara Yuh
Published: March 2013

Y1-xGdxBa2Cu3O7-yfilm with BaZrO3was fabricated on CeO2buffered LaMnO3/ion beam assisted deposition MgO/Gd2Zr2O7/Hastelloy C276TMsubstrates by the trifluoroacetates metal organic deposition process, whose microstructural and elemental analyses were performed by transmission electron microscopy. Y1-xGdxBa2Cu3O7-yfilm with the thickness about 700 nm was found composed of c-axis oriented grains and large numbers of randomly oriented precipitates, such as (Y,Gd)2Cu2O5, CuO and BaZrO3. (Y,Gd)2Cu2O5and CuO precipitates were heterogeneously dispersed in the Y1-xGdxBa2Cu3O7-ymatrix with their sizes ranging between 100 and 200 nm, and BaZrO3precipitates were uniformly dispersed with their sizes ranging between 10 and 20 nm. Electron tomography with elemental information was performed further to reveal the three-dimensional information of BaZrO3 precipitates.
Fabrication of Cu Nanowires and its Effect on Proliferation of Mesenchymal Stem Cells
Authors: Song Yuan Hui , Ju Yang , Zhang Lan , Morita Yasuyuki , Song Guan Bin
Published: March 2013

Many studies have focused on the fabrication of Cu nanowires, because of their potential applications in diverse fields such as nanoelectronics and gene delivery. In this study, we successfully fabricated Cu nanowires by electrochemical deposition method. Cu nanowires was synthesized by electroplating from a 0.4M CuSO4 bath, and the current was 0.005A. The length of nanowires can be controlled via deposition time and current. After depositing for 60 minutes, the length of the nanowires is approximately 10 µm. Serum coated and non-coated nanowires with the concentration of 102, 103, 104 and 105 were added to 96-well cell culture plate in which mesenchymal stem cells were pre-seeded. After incubating for 3 days, cytotoxicity of nanowires was measured with MTT assay method. Results indicated that cytotoxicity increased as the increase of nanowires concentration. Serum coated nanowires had higher cell viability as compared with the non-coated group.
Nanoporous Copper Dealloyed from a Nanocrystallized Ticu Alloy
Authors: Dan Zhen Hua , Qin Feng Xiang , Sugawara Yu , Muto Izumi , Hara Nobuyoshi
Published: March 2013

Nanoporous copper (NPC) was fabricated through dealloying nanocrystallized TiSubscript text50Cu50 ribbon alloy under a free immersion condition in HF solutioSubscript textns at 25 °C. Multimodal nanoporous structure was formed due to the presence of Ti3Cu4 phase, which was co-precipitated with Ti2Cu during the heat treatment at T = 400 °C (Italic textTSubscript textg Italic textT Subscript textx). The presence of multiphases in tItalic texthe starting material caused the different behavior in the evolution of nanoporosity. In 0.03 mol/L HF solution, the bimodal nanoporous copper with a pore size of 54 nm and 184 nm was obtained in different regions where the composition differed. The ligament scale lengths in two regions were confirmed to be 54 nm and 203 nm, respectively. In 0.13 mol/L HF solution, the difference in the pore size and phase separation became weak, accompanying with the evolution of larger pores and smaller ligaments. The residue after dealloying was confirmed to be fcc Cu, indicated by the presence of Cu (111), (200), (220) and (311) in XRD patterns and TEM selective area diffraction pattern. The microstructure of the starting materials for dealloying, such as intermetallic phases, played a key role in the formation of the final multimodal nanoporous structure.
Combined Experimental and Numerical Approach for Linking Microstructure and Mechanical Properties on Different Length Scales for near γ–TiAl Alloys
Authors: Kabir Mohammad Rizviul , Bartsch Marion , Chernova Liudmila , Schneider Janine , Kelm Klemens
Published: March 2013

At room temperature the macroscopic tensile behavior of TiAl alloys is extremely microstructure sensitive. In general the microstructures of TiAl alloys are heterogeneous at micro and meso scale. The materials micromechanisms that occur at different length scale have to be linked for a proper understanding of the macroscopic response. In order to explore those micromechanisms, methodologies combining advanced experimental and computational analysis have been proposed. Linking microstructure and properties using a two-scale numerical model we are able to explain the stress-strain and hardening behavior of this alloy.
Macro-Model for Development of Al-SiC Metal Matrix Composite with Vacuum Moulding: Designed Experiments
Authors: Singh Jaswinder , Singh Rupinder
Published: March 2013

Metal matrix composites (MMC) have many potential engineering applications. Not much work hitherto has been reported for development of Al based MMC with vacuum moulding (VM) process. In this work; Aluminum (Al) based MMC has been developed with VM. An approach to macro-model the micro hardness and dimensional accuracy for development of Al-SiC, MMC has been proposed and applied during VM process. Relationship between micro hardness, dimensional accuracy and other input parameters of VM process has been deduced by using Taguchi technique. The comparison with experimental results will also serve as a future validation of the model.
ZnO Nanoparticles to Nanowires and Nanobundles
Authors: Hossain Mohammad Kamal
Published: March 2013

Nanosized Zinc oxide (ZnO) possesses unique electrical, optoelectronics and photochemical characteristics and thus it is a potential candidate for different applications in next generation of optoelectronic device. In this work, a novel sol-gel route for the synthesis of ZnO nanoparticles and its transformation into wires and bundles has been reported. The process is adopted from a simple and hand-on route that also shows the power of green chemistry in nanomaterials synthesis. ZnO nanoparticles (~30 nm in diameter) were synthesized from bottom-up approach followed by a further process to obtain nanometric wires and bundles under controlled conditions. The nanowires and bundles are speculated to initiate from anisotropic agglomeration of nanometric particles and agglomeration of these nanometric wires into bundles respectively. Control of these agglomeration processes is a key challenge for application of nanowires and bundles into useful devices.
Study on Bactericidal Effect of Biosynthesized Silver Nanoparticles in Combination with Gentamicin and Ampicillin on Pseudomonas aeruginosa
Authors: Rajawat Shweta , Qureshi M.S.
Published: March 2013

Silver nanoparticles are the most promising nanomaterial with antibacterial properties. Recent study of resistance to most potential antibiotics promotes research in the bactericidal activity of the silver nanoparticles. In this work, the effect of biosynthesized silver nanoparticles, in combination with gentamicin and ampicillin, on Pseudomonas Aeruginosa bacteria has been studied. Pseudomonas Aeruginosa is a common bacterium that can cause infections which are generalized as inflammation and sepsis. The results show that the bactericidal properties of the nanoparticles depends on the size of the as-synthesized silver nanoparticles as nanoparticles of diameter ~120 nm only have a direct interaction with the bacteria. It is observed that the antibacterial activities of antibiotics increase in the presence of AgNPs against test strains. Silver nanoparticles were synthesized elctrolytically using silver wire of 99% purity as anode and carbon rod wrapped with LDPE as cathode. 0.01 N Silver nitrate was used as an electrolyte. The process is termed as biosynthesis, because tea extract was used used as the capping agent which is also a very mild reducing agent. The polyphenols theaflavins and thearubigins, present in tea perform the role of stabilizing or capping agents due to their bulky and steric nature. A brown colored colloidal solution of silver nanoparticles is obtained. The as-synthesized silver nanoparticles were characterized using XRD, TEM and UV-Vis spectroscopy.
Light Extraction from GaN-Microcavity
Authors: Ahmed Naser Mahmoud , Hassan Z.
Published: March 2013

t will be demonstrated that light extraction of GaNcan be more efficient with the use of flat and dome epoxy. Theoretically the angle, wavelength, and thickness depend on the photoluminescence emission of the luminescent film of transparent substrate. This was studiedusing theFresnel type transmittance calculations for s- (TE) and p- (TM) polarized emission. Experimentally we have demonstrated a GaN/sapphire microcavity exhibited in the 1.3-1.6 fold enhancement in light extraction efficiency by using flat and dome epoxy as external medium compared with air external medium. In addition, simulation results shows that using (HfO2(), Epoxy (),MgF2 (), Air ()) improve the light extraction by increasingthe critical angle and diffracting the internal light with a large solid angle into the light escape cone.
Control-Oriented Modelling of Spatial Motion of Autonomous Underwater Vehicle
Authors: Garus Jerzy
Published: March 2013

Modelling of three-dimensional motion of an underwater vehicle along a time-varying reference trajectory with predefined speed profiles is presented in the paper. A nonlinear mathematical model with unknown nonlinearities describes the vehicle’s dynamics. Command signals are generated by an adaptive autopilot consisting of three independent controllers with a parameter adaptation law implemented. A control performance is guaranteed by suitably choosing design parameters. Selected results of computer simulations are inserted to demonstrate quality and effectiveness of the approach.
An Algorithm for Generation of Coordinated Robot Trajectories in Cartesian Space
Authors: Słota Adam
Published: March 2013

In the paper a trajectory generation algorithm for two robots’ coordinated motion is presented. Two instances of the algorithm, each for one robot, run in the same time and calculate trajectories’ position and orientation coordinates. Initial and end robots’ end-effectors poses are defined and values of linear and angular speeds are programmed. To minimize relative position and orientation errors an idea of corrective motion is introduced. Trajectory coordinates are calculated as the sum of programmed and corrective motion. The algorithm was implemented in a simulation environment and results of simulation are presented. Static accuracy analysis for general case and stability verification for fixed values of robots’ parameters are described. Finally, an outline of proposed procedure of building a virtual environment for reachability verification and collision checking is presented.
The Analysis of Possibility of Using Electromagnetic Drive for Autonomous Biomimetic Underwater Vehicle
Authors: Grzeczka Grzegorz
Published: March 2013

Striving for a perfect imitation of fish motion is one of assumptions of building autonomous biomimetic underwater vehicle. Usage of typical servomechanisms gives good results, but it is important to eliminate their two main disadvantages: large power consumption and constant torque in whole range of motion. In the paper, an analysis of possibilities of using set consisting of a permanent magnet and an induction coil for electromagnetic drive of the vehicle was included. Values of driving torque and character of its change in comparison with muscle system of fish were estimated.
Microstructural Characterization of Thermal Barrier Coatings Deposited by APS and LPPS Thin Film Methods
Authors: Góral Marek , Pytel Maciej , Sosnowy Pawel , Kotowski Slawomir , Drajewicz Marcin
Published: March 2013

In the paper first results of TBCs deposition by LPPS-Thin Film method were presented. The LPPS-Thin Film is a new type of processes for deposition of thermal barrier coatings. In this method deposition of thin ceramic layer in very low pressure is possible as well as coatings with columnar structure (in plasma spraying-physical vapour deposition process). The MeCrAlY bond coats were deposited by APS method. The overaluminising by CVD method of conventional MeCrAlY was also conducted. The analysis of microstructure of both type bond coats as well as outer ceramic layer were presented using light and scanning electron microscopy methods. Results of EDS microanalysis showed the increasing of aluminum content in outer zone of overaluminized MeCrAlY coating. In ceramic layer the columnar structure were observed which was connected with powder evaporation during plasma spraying. The new type of MeCrAlY-NiAl bondcoat could increase the oxidation of TBCs deposited by LPPS Thin Film method.
An Application of Computer Tomography for Structure Characterization of Metallic-Ceramic Composite Foam
Authors: Grabian Janusz , Gawdzińska Katarzyna , Wojnar Leszek , Przetakiewicz Wojciech
Published: March 2013

Authors of the paper present structures of composite metallic-ceramic foams (Al11SiC) of characteristic internal composition, produced at Maritime University of Szczecin. Diversification of pore size and structure of composite walls is present. The foams are manufactured by injection of a gas into a liquid composite using a special device, which allows to realize the foam manufacturing process in a continuous manner. This device also allows to control the parameters of the foaming process, which results in possibility of influencing, among other things, the size and the size distribution of formed gas bubbles. After manufacturing foams with both homogeneous and diversified gas pores, basic mechanical properties of these foams were examined, revealing a connection with their structure. Possibilities of applied research methods, utilizing a microscope and a tomograph, were also presented. Methods using computer image analysis were selected for the structure description.
The Effect of B and Microalloying Elements (V, Ti, Nb) Additions on the Austenite Grain Growth of Low Alloy Steel
Authors: Adrian Henryk , Pelczar Marta , Adrian Anna , Augustyn-Pieniążek Joanna
Published: March 2013

The effect of B and microalloying additions of V, V+Ti, V+Nb on austenite grain growth of low alloy steel containing 0.3% C, 1 % Cr and 0.2 % Mo was investigated. As a measure of austenite grain size the mean chord length of austenite grains was assumed. The boron content in investigated steel was in the range of 0 to 0.008 %. The investigations were carried out in austenitising temperature range of 850 to 1100oC. Using the thermodynamic model the contents of undissolved compounds of carbonitride V(C,N) and boron nitride BN were calculated and the effect of undissolved compounds content on austenite grain size was investigated. Obtained results showed, that vanadium content below 0.1 % was ineffective as austenite grain growth inhibitor of boron containing steel and austenite grain size of steel was higher compare to non-alloyed steel. The most effective for decreasing of austenite grains size of boron containing steel was addition of 0.18 % V + 0.03 % Nb
Effect of Processing Conditions on Microstructure of SiC-TiB2 Composite
Authors: Górny Gabriela , Stobierski Ludosław , Rutkowski Paweł , Rączka Marian
Published: March 2013

The objective of the study as described in this paper is to analyse the effect of processing conditions as: volumetric content of TiB2 powders and the time of milling them on the parameters of microstructure of particulate composite with a SiC matrix and 10 or 20 vol.% of the TiB2 as dispersed phase. From the initial research conducted by the authors, as well as from the data contained in the reference literature, it is known that the SiC-TiB2 composite is a potential material to be applied in the manufacture of cutting tool inserts. To manufacture composites, SiC powders (Starck, UF-15) and TiB2 powders (Momentive, HCT-30) were used; they were milled for 15 or 30 h in a vibrating-rotating mill with silicon carbide balls as grinding media. The SiC-TiB2 composite was manufactured using a hot pressing method under the following conditions: temperature: 2120 oC; pressure: 25 MPa; and sintering time: 30 min. Under the stereological analysis of SiC-TiB2 some selected microstructural parameters were measured, i.e.: volume fraction of TiB2, average size of TiB2 particles, mean diameter of particles (D), shape factor of TiB2 particles, α, as well as NA and NV parameters that determine the quantity of TiB2 particles contained in the composite. Computer-aided analysis of microstructure of the SiC-TiB2 composites and analysis of results of measurements of mechanical properties of these composites prove their the microstructure and properties depend on the volumetric content of TiB2 dispersed phase, and this dependence is significant.
The Effect of Austenitizing Temperature on Prior Austenite Grain Size in Martensitic Cast Steel
Authors: Golański Grzegorz , Kolan Cezary , Kupczyk Jerzy
Published: March 2013

The GX12CrMoVNbN9-1 (GP91) cast steel belongs to a new group of high-temperature creep resistant cast steels being introduced to the power industry. The cast steel is characterized by higher mechanical properties in comparison with the low alloy Cr – Mo or Cr – Mo – V cast steels used so far. The mechanical properties of martensitic cast steels depend on the parameters of heat treatment, such as the temperature of austenitizing. The paper is to present the results of research on the influence of austenitizing temperature ranging from 980 to 1100oC and hold time of 12 hours on the growth of austenite grain. The tests were carried out on test samples taken from a test coupon. Description of the influence of austenitizing temperature on the austenite grain size was made using the mean diameter of grain. Performed tests have shown that the distributions of mean diameters are of normal character, on the significance levels α = 0.05 and α = 0.04. For the investigated temperature range, the ν coefficient of non-homogeneity of the mean diameter of prior austenite grain was determined. The achieved results have proved that in the temperature range of 1010 to 1070°C the mean diameters stay within the same grade of grain size and the considerable grain growth is visible at the temperature of 1100°C.
Path Planning with the Use of Artificial Ant Colony Algorithm
Authors: Vĕchet Stanislav , Ripel Tomas
Published: March 2013

Finding a way through an unexplored environment belongs to actual problems in many artificial agent systems. Common algorithms as state-space searching or rapidly exploring random trees are used when the map of given environment is known. In this paper we present simulation experiments with multi agent system represented as artificial ant colony.
Structures of the Omnidirectional Robots with Swedish Wheels
Authors: Tătar Mihai Olimpiu , Cirebea Claudiu , Mândru Dan
Published: March 2013

In the first part of the paper, specific aspects concerning the omnidirecional Mecanum wheels are presented, while the second part is dedicated to the presentation of two prototypes of omnidirectional robots, equipped with omnidirectional Swedish wheels.
Vision Analysis of a Biomimetic Water Vehicle Propeller
Authors: Sioma Andrzej , Lepiarz Wojciech
Published: March 2013

Water and underwater vehicles are driven by propellers. Various models use propellers with 2 to 7 blades with either fixed or controllable pitch. Another known solution are water-jet propellers. Water is sucked from the front of the vehicle and ejected through a nozzle at the rear. A propeller is usually the water pumping component. This paper presents the design of a novel type of water-jet propeller, inspired by the way animals move in the aquatic environment. It discusses the mechanisms of propeller operation and its structural solutions. It also presents theoretical simulation studies and actual studies on a real object, which enabled assessment of the propellers parameters.
Algorithms of Measurement System for a Micro UAV
Authors: Kopecki Grzegorz , Tomczyk Andrzej , Rzucidło Paweł
Published: March 2013

The article presents a measurement system for a micro UAV designed at the Department of Avionics and Control Systems of Rzeszów University of Technology. Since the project is based on earlier projects, e.g.[[[[1[[[1, the introduction begins with their short presentation [they are mentioned in the introduction firs. Then, the current project is discussed. The major objective of the project is to create a miniature autopilot cooperating with navigation units, data transmission units and measurement units. The system is based on Polish technological solutions. The autopilot is designed as a single unit, however the system is open and it allows you to use different elements. The system development is also possible. In-flight testing will be realized with the use of two unmanned flying platforms equipped with an electrical engine and a piston engine. The total mass of the platforms is 5 kg and 25 kg respectively. The article presents the structure of the control and navigation system and then, the structure of the measurement system. The measurement units consist of a GPS receiver, an attitude and heading reference system (AHRS) and an air data computer (ADC). Similar configuration is used in other micro UAV solutions, such as Micropilot or Kestrel. Then, algorithms of the measurement system are described. Navigation is based on GPS data with a DGPS (Differential GPS) advanced module. If the measurement information is complete, GPS data are used to correct measurements from other units. The system estimates wind disturbances and calculates accelerometers errors. In the case of missing GPS signals implementation of low-cost sensors may lead to significant measurement errors, and hence navigation only by means of the INS is impossible. In such a case, navigation is realized with the use of an inertial navigation system (INS), the magnetic heading measurement and ADC. AHRS unit algorithms use quaternion algebra for attitude calculation. For correction, complementary filtering is implemented [, [. The correction signal for the attitude (pitch and roll angles) is calculated with the use of acceleration measurements. Measurements of accelerations and yaw rates are used for the correction switching mechanism, since in dynamic states signals calculated from accelerations cannot be used for correction. Heading is corrected by means of magnetic heading measurement. ADC algorithms are based on typical aerodynamic dependences.
Autonomous Flight in the Canyons of Streets on the Basis of Information Derived from the Vision System
Authors: Kownacki Cezary , Bogdan Mariusz
Published: March 2013

This article presents algorithm of autonomous microplane flight control in street canyons using image from a camera as a carrier of information about microplane surroundings. Algorithm structure and video information processing are formed in a way that enables their implementation with the use of available equipment such as microcameras, advanced autopilot and signal processor DSP. On the basis of the developed algorithm model simulation research was prepared and conducted. Obtained results confirm effectiveness of this algorithm in autonomous flight control of microplane in street canyons. However, conducted simulations did not use real video image, but only simplified model of street map perspective image.
Mechatronic Design of a Parallel Robot for Milling
Authors: Petko Maciej , Karpiel Grzegorz
Published: March 2013

The paper presents the process of development of a parallel manipulator for milling, and justifies why mechatronic approach can lead to successes. The resulting construction is a novel, versatile 3-RRPRR, fully-parallel manipulator with three translational degrees of freedom, characterizing in comparatively high payload capacity, large workspace and high attainable accelerations. The construction of the manipulator is shown, with analysis of its kinematics and dynamics. A controller is proposed, simulated and experimentally investigated. Finally, the conclusions and future works are presented.
The Analysis of the Influence of the Design Parameters on the Performance Characteristics of a Mini UAV
Authors: Majka Andrzej
Published: March 2013

In the conditions of the growing intensity of the UAV usage one of the most important problems is the improvement of their technical and performance effectiveness. It can be achieved applying the advanced methods of optimal designing. Apart from constructing an appropriate calculation model of the UAV, such an approach requires separating a group of decisive parameters, determining the limits and choosing the criterion of optimization. The precision and the range of use of the constructed calculation model must be adequate to a particular task allowing the optimal choice of characteristics of an aerial vehicle. Selection of the design parameters requires answering the question which technical parameters (geometrical, constructional etc.) of the UAV influence the performance characteristics of the aircraft positively. Analyzing the gradients of the performance characteristics change depending on the change in the design parameters, it is possible to determine the level of precision when determining the values and formulating the condition of finishing the optimization calculations. The aim of this work was to analyze the influence of selected design parameters on the performance characteristics of a mini UAV.
Mechatronic System for the Production of Highly Secured Documents
Authors: Samborski Tomasz , Zbrowski Andrzej
Published: March 2013

The article presents a mechatronic system for the production of highly secured documents that allows for the realization of R&D tasks directed at the improvement of the level of security of electronic and physical RFID tags. The structure of the system allows for the application of special, low cost, flexible production systems enabling free use of developed innovative technologies, structures, components, formulas and procedures. The system is based on two technological lines. The first of them enables the manufacture of multilayer (glued), graphically and electronically non-personalised products that vary in size and shapes in the conditions of low cost experimental production. The second line allows for the introduction of unique graphic information in form of overprints assigned to suitable data entered into the microprocessor memory. Adequate verification systems compare the compatibility of the electronic record with the alphanumeric information and the conformity of digital graphics with the graphics in form of the overprint visible in certain lighting conditions. The additional application of the two-sided lamination results in the increased mechanical and physical endurance and resistance to non-authorised changes of graphic and alphanumerical information.
Homogeneous Flow of Hydraulic Fluid Retaining Gap
Authors: Ułanowicz Leszek
Published: March 2013

This paper presents the laminar flow of homogeneous liquids in crevices of smooth hydraulic resistance. The paper presents a theoretical model for the distribution of pressure in the gap and the flow rate through the slot hydraulic. The presented theoretical models for the distribution of pressure and flow in the gap on conventional hydraulic resistance of hydraulic joints, whose shape is related to the errors of their execution. In deriving the theoretical models, by introducing a variable height of the gap in the initial episode, was founded stream velocity profile variability in the hydraulic fluid retaining gap and zero values of local losses at the entrance to the slot. An analysis of the validity of the simplifications adopted in the given formulas for the distribution of pressure and flow in the hydraulic gap and on the basis provides guidelines for estimating the energy losses that occur cracks in the hydraulic resistance.
Redundantly Actuated 3RRR Parallel Planar Manipulator - Numerical Analyses of its Dynamics Sensitivity on Modifications of its Platforms Inertia Parameters
Authors: Lipiński Krzysztof
Published: March 2013

Below, numerical analyses, as well as dynamics of a complex mechanism, are presented. Two objectives are focused: inverse dynamic model is needed (dedicated to be use in the model predictive controller); an identification method is searched (some trajectory parameters are controlled, when specific trajectory is tracked under an open-loop model-based control), as selected parameters must be identified for the model. A redundantly actuated mechatronic system is considered (in the present case some planar, parallel manipulator). When the redundancies are present, traditional torque estimation techniques can not be used directly (a non-square matrix is present in the equations). Thus, the right Moore-Penrose pseudo-inverse is used to estimate them. To model the mechanism - multibody dynamics is used. Its dynamics equations are nonlinear in respect to the joints position (displacements are significant during the mechanism motion). An open-loop model-based control algorithm is postulated for the system (the subcomponents from the closed-loop controller will not be considered in the present paper). As the real parameters of the controlled object can differ from the ones proposed in the controller, obtained trajectories differ from the requested (open-loop controller is used only). Correlations between the inertia error and the trajectory errors are tested. Sensible trajectory parameters are searched to estimate inertia of the controlled object. At present, analyses are restricted to numerical experiments, only.
Mechatronic System for Impact Tests for Aero Structures
Authors: Zbrowski Andrzej , Majcher Andrzej
Published: March 2013

The article presents the structure of the developed pneumatic propellant system for impact tests particularly conducted in the aviation. The solution is intended for the realization of experimental tests enabling the simulation and recreation of the event of collision of the aircraft, or other means of transport, with the solid object or a bird in motion. The projectile thrower has been designed in form of a 250 mm pneumatic cannon. The size and the energy parameters of the cannon enable the objects weighing several kilograms to be thrown with the speed reflecting the actual collision of the aircraft with a big bird, both in the areas of subsonic and supersonic crash speed. In order for the complex realisation of the impact tests, the structure of the test system for impact tests with the option to record the event by means of a synchronised vision path and an impact force measurement path, has been developed.
Modelling of the Planar Aerostatic Two-Coordinate Relative Bases
Authors: Huścio Tomasz , Siemieniako Franciszek
Published: March 2013

The paper describes the construction and the principle of operation of a planar aerostatic two-coordinate relative base. The physical model and the mathematical description of a planar aerostatic two-coordinate relative base are presented. Stages of the computer simulation of the planar aerostatic two-coordinate base and the computer simulation results are presented.
Remote Advanced Supervision and Diagnostics of Robotized Welding Cell
Authors: Pilat Zbigniew , Zieliński Jacek , Słowikowski Marcin
Published: March 2013

Welding equipment and other components included in the robotized or automated welding station are now usually equipped with advanced control. It not only enables effective exchange of the information between components of the system, but also allows to implement a very efficient hardware and software diagnostic tools, which is not commonly utilized, especially in smaller installations. The use of communication controllers and devices connected to the global network shall enable the realization of such monitoring in remote mode and with the use of modern ICT solutions the effectiveness of such monitoring will be greatly increased. Device operators and technologists will gain the ability to monitor remotely the status of these devices as well as the processes even in the real time [. This article presents a practical solution of implementing remote monitoring to the welding installation with the use of WEB2.0 services.
Rubber Structural Coupon Behaviour Study under Pressure Impulse
Authors: Baranowski Pawel , Malachowski Jerzy , Mazurkiewicz Łukasz , Damaziak Krzysztof
Published: March 2013

This study focuses on the rubber material behaviour assessment under dynamic loading using numerical methods. Consequently, dynamic simulations of the rubber structural coupon subjected to dynamic velocity loading were performed using the explicit integration procedure with central difference scheme with modified time integration of the equation of motion implementation. During investigations two impulse velocities were used and compared for two different constitutive materials: Mooney-Rivlin without rate-dependency and Mat 181 Simplified Rubber which includes strain rate effects. From the obtained results it was noticed that material behaviour in both cases is different and along with different values of velocity the strain rate sensitivity changes.
Second-Order Model of the Radial Passive Magnetic Bearing with Halbach's Array
Authors: Falkowski Krzysztof
Published: March 2013

In the paper is presented model of the passive magnetic bearing. The response of bearing is approximate by second order model. There are presented the damping and stiffness coefficient of suspension. The coefficients derived from Biot-Savards law, Ohms law and Lorenzs force. There is presented loop with molecular current as a model of magnet, final formula of damping and stiffness coefficients and static characteristic of passive magnetic bearing.
Simulation Model of an Electromagnetic Multi-Coil Launcher for Micro Aerial Vehicles
Authors: Kondratiuk Mirosław , Gosiewski Zdzisław
Published: March 2013

The paper presents a model of the 10-coil launcher, which can be used as a catapult of micro aerial vehicles (MAVs). The main advantage of such a device is the possibility of controlling its acceleration. We have also shortly described main disadvantages of pneumatic and rubber launchers and compared them to our solution which involved magnetic phenomena. The history and the classification of magnetic launchers were also mentioned. The investigated magnetic system was described in details. The system voltage equations and energetic conversions which take place during the launch were presented. With the use of finite element method we calculated the lumped parameters of the system (self-and mutual inductances). Nonlinear model was implemented in the MATLAB packet. Launch operation was divided into an acceleration and a braking phase. Thus, nine coils operated as accelerators and the last one was employed as a magnetic brake. The system was controlled by means of PID regulators which were tuned manually. Current values in the modelled coils were also limited by bang-bang controllers. In the last part of the paper we presented results of simulations and discussion about possible improvements of the model in the future.
Active Synthesis of Discrete Systems as a Tool for Reduction Vibration
Authors: Dymarek Andrzej , Dzitkowski Tomasz
Published: March 2013

The paper presents the problem of vibration reduction in designed discrete mechanical systems. The method of reduction has been based on active synthesis, which makes it possible to obtain the desired mechanical effect through the proper selection of dynamic properties of the system, including the calculation of the active force as a function of the system force feedback.
Modeling of a Battery Electric Vehicle (BEV) for Efficient Model-Based Design
Authors: Buchta Robert , Liu-Henke Xiao Bo
Published: March 2013

For an efficient design process of complex mechatronic systems a continuous and verification-orientated model-based methodology with Model-in-the-Loop (MiL), Software-in-the-Loop (SiL) and Hardware-in-the-Loop (HiL) simulation is suitable. Using such an approach the real-time capable nonlinear multi-body system model of the entire vehicle with the electric power train and the identification of the physical parameters are described. A continuous appliance of the introduced model is a contribution for the frontloading and guarantees a time and cost efficient mechatronic design approach.
Speed/Position Sensorless Control of Two-Phase Induction Motor Drive System Using Virtual Injection Method
Authors: Dobrucky Branislav , Kascak Slavomir , Prazenica Michal
Published: March 2013

The paper deals with speed/position servosystem with 2-phase electrical induction motor for robotic applications. The new developed method has been used for speed/position control. The precision of position determination is less than 2.5 o el. in steady-state operation in spite of virtual sensorless method. It needs for real time control - high computing power for control algorithms and very small time sampling interval. Maximum of motor electromagnetic torque is providing by field oriented control (FOC).
Synthesis of New Mechatronic Systems by Inverse Algorithm
Authors: Viba Janis , Cifanskis Semjons , Tipans Igors
Published: March 2013

nverse method algorithm for invention of mechatronic systems in vibrotechnics is used for robotic systems motion control synthesis. The main difference between this method and simple analysis method is that before synthesis of a real system optimal control task for abstract initial subsystem is solved. After calculations the optimal control law is found that allows to synthesise series of structural schemes for real systems on a basis of initial subsystem. It is shown that optimal control action corresponds to the case of boundary values of area limits. For realizing optimal control actions in general case a system of one degree of freedom needs feedback system with two adapters: one for measure displacement and second for measure velocity. It is shown that simple case exists of the control with only one adapter when motion changes directions. It means that control action is like negative dry friction and switch points are along zero velocity line.
The Simulator for Teaching how to Drive a Car for People with Disabilities
Authors: Dymarek Andrzej , Dzitkowski Tomasz , Herbuś Krzysztof , Kost Gabriel , Ociepka Piotr
Published: March 2013

This work presents ideas for a passenger car driving simulator for teaching the disabled. The functional structure, design assumptions, and the concept and operation of the proposed simulator are presented.
The Control System for a Vibration Exciter
Authors: Konieczny Jarosław , Sibielak Marek , Rączka Waldemar
Published: March 2013

The paper presents the control system for an electro-hydraulic vibration exciter. A vibration exciter is used to carry out kinematic and forced excitations. Such excitations are needed during the static and dynamic examinations of suspension assemblies and their elements, such as damping springs. The most important elements of the exciter are: a hydraulic servo valve, a hydraulic actuator, a control system and a hydraulic supply station. An inductor works in a negative feedback loop. A set point generator and controller are parts of a real-time control system. The authors used a cRIO-9022 industrial computer from National Instruments analogue input and output modules. Apart from supporting I/O modules, the cRIO controller in a real-time system communicates with an FPGA circuit that forms a control loop. The use of an FPGA (Field Programmable Gate Array) allowed for implementing a hardware control loop through a vibration exciter, as well as other control loops used in the research (such as controlling an active executive element). The use of such a system architecture enabled the parallel operation of multiple control threads. The selected structure also allows for flexible selection of the measuring channels, which are essential for system monitoring and data acquisition.
A Simplified Model of 3-D Pipe System Conveying Flowing Liquid
Authors: Orlikowski Cezary , Hein Rafał
Published: March 2013

This paper presents a model reduction technique of a 3-D pipe system with flowing liquid. In the analysis and design of control (mechatronic) systems it is useful to work with simple, low order models. A hybrid reduced order model is proposed. The system model consists of two parts, the modal model and the finite element model.
Development and Validation of Numerical Model for Predicting Electromagnetic Expansion of Composite Rings
Authors: Janiszewski Jacek , Panowicz Robert
Published: March 2013

In the present work, the description of a numerical model for predicting the electromagnetic composite ring expansion process and validation of a developed numerical code is presented. The strength response of rings materials under high strain rate deformation was described by using the well-known JohnsonCook constitutive relationship. Numerical considerations and experimental validation were performed for a composite ring consisted of a copper drive ring and X37CrMoV51 steel ring specimen. The analyses of the obtained results allow to find out that good convergence of theoretical and experimental data was achieved.