scholarly journals ABOUT DETERMINING THE POSITION OF THE GEOGRAPHIC MERIDIAN THREE-STAGE PENDULUM GYROCOMPASS DURING ACCELERATION OF ITS ROTOR

2014 ◽  
pp. 49-54
Author(s):  
Володимир Миколайович Федоров
Keyword(s):  
Indirect Method ◽  
Operation Mode ◽  
Vertical Axis ◽  
Processing Unit ◽  
Position Sensor ◽  
Single Measurement ◽  
Angle Sensor ◽  
Azimuthal Position ◽  
Torsion Suspension ◽  
Northerly Direction

The article considers three-stage pendulum gyrocompass ground with torsion suspension unmanaged sensor, equipped with high-precision digital angle sensor azimuthal position sensor and information processing unit. During processing of information isused an indirect method to get facts about initial deviations of dynamical systems.In the process of improving the instrument have revealed that a further increasing of accuracy due to the necessity to consider the following factors. During the measurement around the vertical axis of the sensor operates permanent uncontrolled moment due to operational reasons are different from measurement to measurement. Specified point shifts the center of oscillation of the azimuthal sensor, which is in accordance with the procedure identified azimuth northerly direction on a constant value. For self-compensation of this error have been proposed several methods based on measurements with different but fixed parameters of the device. However, these measures have extended more than twice the measurement process.In this article there is proposing to define the position of the geographic meridian based on the analysis of the azimuthal motion sensor gyro during acceleration of its rotor. The proposal can bring dual gain in reducing measurement time: at first, the rotor becomes "staff " rather than ballast gyro operation mode, as it was before; secondly, there is no need for special measures to combat harmful vertical moments, as the shift of the equilibrium caused by the action of the latter, is variable in time, which allows to determine the magnitude of harmful moment during a single measurement.

Effect of Blade Inclination Angle on a Darrieus Wind Turbine

2010 ◽  
Author(s):  
Marco Raciti Castelli ◽  
Ernesto Benini
Keyword(s):  
Wind Turbine ◽  
Inclination Angle ◽  
Vertical Axis ◽  
Energy Performance ◽  
Vertical Axis Wind Turbine ◽  
Azimuthal Position ◽  
Induced Drag ◽  
Axial Forces ◽  
Phase Shift Angle ◽  
Modeling Software

This paper presents a model for the evaluation of energy performance and aerodynamic forces acting on a small helical Darrieus vertical axis wind turbine depending on blade inclination angle. It consists of an analytical code coupled to a solid modeling software, capable of generating the desired blade geometry depending on the desired design geometric parameters, which is linked to a finite volume CFD code for the calculation of rotor performance. After describing and validating the model with experimental data, the results of numerical simulations are proposed on the bases of five machine architectures, which are characterized by an inclination of the blades with respect to the horizontal plane in order to generate a phase shift angle between lower and upper blade sections of 0°, 30°, 60°, 90° and 120° for a rotor having an aspect ratio of 1.5. The effects of blade inclination on tangential and axial forces are first discussed and then the overall rotor torque is considered as a function of azimuthal position of the blades. Finally, the downstream tip recirculation zone due to the finite blade extension is analyzed for each blade inclination angle, achieving a numerical quantification of the influence of induced drag on rotor performance, as a function of both blade element longitudinal and azimuthal positions of the blade itself.

Wind Tunnel Hotwire Measurements, Flow Visualization and Thrust Measurement of a VAWT in Skew

2006 ◽  
Vol 128 (4) ◽  
pp. 487-497 ◽  
Author(s):  
Carlos J. Simão Ferreira ◽  
Gerard J. W. van Bussel ◽  
Gijs A. M. van Kuik
Keyword(s):  
Flow Visualization ◽  
Operation Mode ◽  
Sampling Rate ◽  
Vertical Axis ◽  
Incoming Flow ◽  
Vertical Axis Wind Turbine ◽  
Tip Vortices ◽  
High Sampling Rate ◽  
Thrust Measurement ◽  
Induced Flow

The results of experimental research on the wake and induced flow around a vertical axis wind turbine (VAWT) in skew are presented. The previous research on VAWTs in skew is limited because this operation mode has only recently been found to be significant in the operation of VAWTs in the built environment. These results contain hotwire measurements of the incoming flow and wake of a VAWT in nonskewed and skewed flow. The high sampling rate of the hotwire data allows the effects of blade passing to be identified. Flow visualization of the tip vortices is also presented. Thrust measurements of the rotor were performed to understand the effect of skew on thrust variation and to compare with analytical predictions.

scholarly journals AJUSTMENT OF THE POSITION SENSOR OF THE ROTOR OF THE SYNCHRONOUS RELUCTANCE MOTOR WITH ANISOTROPIC MAGNETIC CONDUCTIVITY OF THE ROTOR

2017 ◽  
pp. 80-86
Author(s):  
Veniamin Frantsevich Samoseyko ◽  
Sergey Vladimirovich Sharashkin
Keyword(s):  
Position Angle ◽  
Position Sensor ◽  
Propulsion Systems ◽  
Angle Sensor ◽  
Rotor Position ◽  
Advantages And Disadvantages ◽  
Reluctance Machine ◽  
Synchronous Reluctance Motor ◽  
Reluctance Motor ◽  
Magnetic Conductivity

The article is devoted to the development of the algorithm for adaptation the rotor position sensor of a synchronous reluctance electric machine with anisotropic magnetic conductivity of the rotor. The main advantages and disadvantages of synchronous electric machines are considered in the construction of ship propulsion systems. The advantages of reluctance motor with anisotropic magnetic conductivity of the rotor are given in the construction of propulsion systems. The essence of the method of adaptation of the rotor position sensor is given. The differential equation of adaptation of the rotor position angle sensor is obtained, its stability is investigated. A model of a reluctance machine with anisotropic magnetic conductivity of a rotor is given, which makes it possible to determine its parameters.

scholarly journals Uji Kinerja Surface Scanner 3D Menggunakan Sensor VL53L0X dan Mikrokontroler ATMEGA8535

2019 ◽  
Vol 11 (1) ◽  
pp. 1-8
Author(s):  
Putut Son Maria ◽  
Elva Susianti
Keyword(s):  
Vertical Axis ◽  
Digital Data ◽  
Processing Unit ◽  
Rotary Table ◽  
Sensor Surface ◽  
Displacement Method ◽  
3D Scanner ◽  
3 Dimensional ◽  
Motor Controller ◽  
Point To Point

Digital data recording of the geometry of 3-dimensional objects require a 3D scanner tool which are mostly using an imagery sensor. However there is hardly used information of scanned result, named color. Imagery sensor requires high spesification processing unit as capable as a personal computer for data acquisition processing. This research aims to build a 3D surface scanner using a time of flight laser ranging sensor and to develop its simple function to become more valuable device. Using point to point displacement method, the sensor measures the distance between the outermost point of the object and the sensor surface perpendicularly, once when one measurement is done then the object to be rotated along with the rotary table. The prototype was built using the VL53L0X sensor and ATMEGA8535 microcontroller as a motor controller for rotary table and vertical axis. Scanned data is sent from the microcontroller to the computer to be visualized in real time. The results show that the VL53L0X sensor is suitable for scanning convex objects but it is not capable to handle objects with multiple cavities.

Phase-chronometric diagnostic system for main drive of rolling mill

2021 ◽  
Vol 77 (6) ◽  
pp. 704-710
Author(s):  
V. I. Pronyakin ◽  
L. Kh. Minyazeva
Keyword(s):  
Mathematical Model ◽  
Rolling Mill ◽  
Pulse Generator ◽  
Operation Mode ◽  
Diagnostic System ◽  
Information Collection ◽  
Time Intervals ◽  
Diagnostic Features ◽  
Angle Sensor ◽  
Working Cycle

At present at the diagnostic of metallurgical equipment state, expert methods of evaluation are prevailed which have subject character. To solve the problem of information-metrological support of rolling mill stand effectively, a phase-chronometric method was proposed, elaborated in N.E. Bauman Moscow State Technical University. It was shown that increase of quality of measuring diagnostical information is provided by transfer from amplitude to chronometric scale and means of its realization at relative errors about 5×10‒4 % at the industrial frequency. At the phase-chronometric method, precision measuring of time intervals, correspondent to the phases intervals of the working cycle is used, depending on characteristic features of motion of a mechanism elements. In contrast to vibro-diagnostic method, by using the phase-chronometric method, the change of operation mode of rolling equipment can be defined hundred times quicker. Cyclicity of a mechanism motion and minimal scattering of measurement results at accomplishing working cycle enable to reveal stable in time diagnostic features and individual quantitative parameters values, which characterize technical state of a rolling mill. The proposed phase-chronometric system consists of an angle sensor of position (incremental encoder), system of information collection and defining of time intervals and personal computer with application software. The system of information collection and defining of time intervals is realized based on a plate, functionally uniting high-stability pulse generator, scale convertor, counter, measuring pulse generator and chrono-comparator. The embedded systems to realize the phase-chonometric metod are simple and reliable in operation. To realize the phase-chronometric method, a mathematical model was elaborated, comprising a system of differential equations, describing interaction of the package of interrelated multi-mass torsion systems. It was showed that verified mathematical model enabled quickly to reveal defects in a rolling mill operation.

Effect of Blade Inclination Angle on a Darrieus Wind Turbine

2011 ◽  
Vol 134 (3) ◽  
Author(s):  
Marco Raciti Castelli ◽  
Ernesto Benini
Keyword(s):  
Wind Turbine ◽  
Inclination Angle ◽  
Vertical Axis ◽  
Energy Performance ◽  
Vertical Axis Wind Turbine ◽  
Azimuthal Position ◽  
Induced Drag ◽  
Axial Forces ◽  
Phase Shift Angle ◽  
Modeling Software

This paper presents a model for the evaluation of energy performance and aerodynamic forces acting on a small helical Darrieus vertical axis wind turbine depending on blade inclination angle. It consists of an analytical code coupled to a solid modeling software capable of generating the desired blade geometry depending on the desired design geometric parameters, which is linked to a finite volume CFD code for the calculation of rotor performance. After describing and validating the model with experimental data, the results of numerical simulations are proposed on the bases of five machine architectures, which are characterized by an inclination of the blades with respect to the horizontal plane in order to generate a phase shift angle between lower and upper blade sections of 0 deg, 30 deg, 60 deg, 90 deg, and 120 deg for a rotor having an aspect ratio of 1.5. The effects of blade inclination on tangential and axial forces are first discussed and then the overall rotor torque is considered as a function of azimuthal position of the blades. Finally, the downstream tip recirculation zone due to the finite blade extension is analyzed for each blade inclination angle, achieving a numerical quantification of the influence of induced drag on rotor performance, as a function of both blade element longitudinal and azimuthal positions of the blade itself.

scholarly journals SiPM-based azimuthal position sensor in ANITA-IV Hi-Cal Antarctic balloon experiment

2017 ◽  
Vol 798 ◽  
pp. 012217
Author(s):  
A Novikov ◽  
D Besson ◽  
I Chernysheva ◽  
V Dmitrenko ◽  
V Grachev ◽  
...  
Keyword(s):  
Position Sensor ◽  
Azimuthal Position ◽  
Balloon Experiment

scholarly journals An Autonomous Doppler Sodar Wind Profiling System

2005 ◽  
Vol 22 (9) ◽  
pp. 1309-1325 ◽  
Author(s):  
Philip S. Anderson ◽  
Russell S. Ladkin ◽  
Ian A. Renfrew
Keyword(s):  
Vertical Axis ◽  
Radio Link ◽  
Research Station ◽  
Processing Unit ◽  
Atmospheric Conditions ◽  
Solar Panels ◽  
Wind Speeds ◽  
Wind Generators ◽  
Doppler Sodar ◽  
Antarctic Continent

Abstract An autonomous Doppler sodar wind profiling system has been designed, built, tested, and then deployed for 2 years at a remote site in Coats Land, Antarctica. The system is designed around a commercially available phased-array sodar (a Scintec flat-array sodar, FAS64) and powered from five modular power system units. Each power unit comprises two batteries, two photovoltaic solar panels, and two vertical axis wind generators, plus charging control and isolation circuitry. The sodar’s main processing unit is located at the antenna, but is controlled from a manned research station 50 km distant, in real time, by a line-of-sight UHF radio link. Data from an integral automatic weather station (AWS) are also transmitted over the radio link, allowing meteorologically informed decisions on whether or not to operate the Doppler sodar. Over the 2-yr experiment dozens of sounding episodes, lasting from a few hours to a few days, were obtained. Successful soundings were obtained in temperatures down to −33°C, and wind speeds up to 12 m s−1. In general, the wind data quality was good, but the range was disappointing, probably as a result of the strongly stable atmospheric conditions that were experienced. The wind profiling system that is described has been used to obtain the first remote wintertime observations of katabatic winds over the Antarctic continent.

Spatial Representations as an Emergent Feature of Perceptual Processing

2010 ◽  
Vol 24 (3) ◽  
pp. 161-172 ◽  
Author(s):  
Edmund Wascher ◽  
C. Beste
Keyword(s):  
Common Ground ◽  
Event Related Potentials ◽  
Vertical Axis ◽  
Relevant Information ◽  
Sources Of Information ◽  
Integrated Network ◽  
Perceptual Maps ◽  
Emergent Feature ◽  
Related Potentials ◽  
Selection Of

Spatial selection of relevant information has been proposed to reflect an emergent feature of stimulus processing within an integrated network of perceptual areas. Stimulus-based and intention-based sources of information might converge in a common stage when spatial maps are generated. This approach appears to be inconsistent with the assumption of distinct mechanisms for stimulus-driven and top-down controlled attention. In two experiments, the common ground of stimulus-driven and intention-based attention was tested by means of event-related potentials (ERPs) in the human EEG. In both experiments, the processing of a single transient was compared to the selection of a physically comparable stimulus among distractors. While single transients evoked a spatially sensitive N1, the extraction of relevant information out of a more complex display was reflected in an N2pc. The high similarity of the spatial portion of these two components (Experiment 1), and the replication of this finding for the vertical axis (Experiment 2) indicate that these two ERP components might both reflect the spatial representation of relevant information as derived from the organization of perceptual maps, just at different points in time.

Single measurement of hemoglobin predicts outcome of HCC patients

2014 ◽  
Vol 52 (01) ◽  
Author(s):  
F Finkelmeier ◽  
D Bettinger ◽  
V Köberle ◽  
M Schultheiß ◽  
B Kronenberger ◽  
...  
Keyword(s):  
Single Measurement
Sign in / Sign up

Export Citation Format

Share Document