scholarly journals Experimental determination of electromagnetic brake parameters of the positioning system

2019 ◽  
Vol 254 ◽  
pp. 03011
Author(s):  
Piotr Perz ◽  
Dominik Wilczyński ◽  
Ireneusz Malujda
Keyword(s):  
Testing Machine ◽  
Effective Control ◽  
Pneumatic Cylinder ◽  
Positioning System ◽  
Electromagnetic Brake ◽  
Hybrid Positioning ◽  
Piston Speed ◽  
Cylinder Piston ◽  
Braking Phase

The paper presents the results of an electromagnetic brake test of a hybrid positioning system consisting of a pneumatic cylinder and an electromagnetic brake. Brake tests were carried out on the MTS Insight testing machine, which determined the attraction forces of the electromagnet depending on the size of the air gap and the current flowing through the winding of the electromagnet. The time constants of the positioning unit and the electromagnet were measured, which allowed to develop an effective control system reaching shorter times and higher positioning accuracy as well as a higher average piston speed. The presented system ensures free programming of displacements of the actuator and maintaining the set position. Obtaining higher average speeds of the pneumatic cylinder piston is possible due to the use of effective control parameters such as shortening the braking phase and the time of reaching the desired position.

Mechanical Behaviour of CoCrMo Alloy with Si Content

2015 ◽  
Vol 754-755 ◽  
pp. 1017-1022 ◽  
Author(s):  
Petrică Vizureanu ◽  
Mirabela Georgiana Minciună ◽  
Dragoş Cristian Achiţei ◽  
Andrei Victor Sandu ◽  
Kamarudin Hussin
Keyword(s):  
Tensile Strength ◽  
Chemical Composition ◽  
Testing Machine ◽  
Base Material ◽  
Optical Emission ◽  
Experimental Tests ◽  
Optical Emission Spectrometry ◽  
Emission Spectrometry ◽  
Standard Samples

.The paper present aspects about the obtaining of non-precious dental alloys (type CoCrMo and CoCrMoSi7), the determination of chemical composition by optical emission spectrometry and the experimental tests for determining the tensile strength, made on standard plate samples. The base material used in experiments was a commercial alloy, from CoCrMo system, which belongs to the class of dental non-precious alloys, intended to medical applications. The obtaining of studied alloy was made on arc re-melting installation, under vacuum, type MRF ABJ 900. The process followed to realize a rapid melting, with a maximum admissible current intensity. The samples for tests were obtained by casting in an electric arc furnace, under vacuum, in optimal conditions for melting and solidification and processing by electro-erosion, to eliminate all the disturbing factors which come by processing conditions for the samples. The determination of chemical composition for cobalt based alloys, by optical emission spectrometry, was made on SpectromaxX equipment with spark. The electrical discharge is made with the elimination of an energy quantity, fact which determine plasma forming and light issue. Tensile tests for standard samples, made from cobalt based alloy, was made on Instron 3382 testing machine, and assisted by computer. The obtained results are: elongation, elasticity modulus, tensile strength and offer complete information about the analyzed mechanical properties. For the certitude of obtained experimental results, the tests were made on samples with specific dimensions according ISO 6892-1:2009(E) standard, both for the tensile strength, and also machine operation.

scholarly journals Assessing the Dynamics and Control of Droplet- and Aerosol-Transmitted Influenza Using an Indoor Positioning System

2017 ◽  
Author(s):  
Timo Smieszek ◽  
Gianrocco Lazzari ◽  
Marcel Salathé
Keyword(s):  
Wireless Sensors ◽  
Public Spaces ◽  
Mitigation Strategies ◽  
Effective Control ◽  
Positioning System ◽  
Close Physical Proximity ◽  
Close Proximity ◽  
Dynamics And Control ◽  
And Control ◽  
Indoor Positioning System

ABSTRACTThere is increasing evidence that aerosol transmission is a major contributor to the spread of influenza. Despite this, virtually all studies assessing the dynamics and control of influenza assume that it is transmitted solely through direct contact and large droplets, requiring close physical proximity. Here, we use wireless sensors to measure simultaneously both the location and close proximity contacts in the population of a US high school. This dataset, highly resolved in space and time, allows us to model both droplet and aerosol transmission either in isolation or in combination. In particular, it allows us to computationally assess the effectiveness of overlooked mitigation strategies such as improved ventilation that are available in the case of aerosol transmission. While the effects of the type of transmission on disease outbreak dynamics appear to be weak, we find that good ventilation could be as effective in mitigating outbreaks as vaccinating the majority of the population. In simulations using empirical transmission levels observed in households, we find that bringing ventilation to recommended levels has the same mitigating effect as a vaccination coverage of 50% to 60%. Our results therefore suggest that improvements of ventilation in public spaces could be an important and easy-to-implement strategy supplementing vaccination efforts for effective control of influenza spread.

scholarly journals Experimental Verification of Pneumatic Cylinder External Pneumatic Cushioning

2019 ◽  
Vol 213 ◽  
pp. 02015
Author(s):  
Lukáš Dvořák ◽  
Lukáš Fuksa ◽  
Marian Ledvoň ◽  
Petr Brzezina
Keyword(s):  
Experimental Verification ◽  
Pneumatic Cylinder ◽  
Measurement Results ◽  
Introductory Part ◽  
Cylinder Piston

This paper deals with the possibilities of the pneumatic cylinder piston end-position cushioning. The introductory part describes the cushioning methods - elastic, hydraulic and internal pneumatic. The second part describes the external pneumatic cushioning, its experimental verification and the measurement results for a specific case.

scholarly journals Energy Efficiency of Pneumatic Cylinder Control with Different Levels of Compressed Air Pressure and Clamping Cartridge

Energies ◽  
2020 ◽  
Vol 13 (14) ◽  
pp. 3711
Author(s):  
Vladislav Blagojevic ◽  
Dragan Seslija ◽  
Slobodan Dudic ◽  
Sasa Randjelovic
Keyword(s):  
Energy Consumption ◽  
Air Pressure ◽  
Compressed Air ◽  
Pneumatic Cylinder ◽  
Final Position ◽  
Return Stroke ◽  
Cylinder Piston ◽  
Reduce Energy Consumption ◽  
The Cost ◽  
Different Levels

Since pneumatic systems are widely used in various branches of industry, the need to find ways to reduce energy consumption in these systems has become very pressing. The reduction in energy consumption in these systems is reflected in the reduction of compressed air consumption. The paper presents a cylinder control system with a piston rod on one side, in which the reduction in energy consumption is ensured by using different levels of supply pressure in the working and the return stroke, and by holding the cylinder piston rod in its final positions with a clamping cartridge. Clamping and holding the piston rod in its final position further affects the reduction in energy consumption. Experimental data show that the application of the proposed control leads to a decrease in compressed air consumption of 25.54% to 32.97%, depending on the compressed air pressure used in the return stroke. The cost-effectiveness of the proposed cylinder control with different levels of compressed air pressure and holding the final position by clamping cartridge is presented.

Dynamic Study of Insole Materials Simulating Real Loads

1994 ◽  
Vol 15 (6) ◽  
pp. 311-323 ◽  
Author(s):  
Ana-Cruz Garcia ◽  
Juan-Vicente Durá ◽  
José Ramiro ◽  
Juan-Victor Hoyos ◽  
Pedro Vera
Keyword(s):  
Dynamic Testing ◽  
Testing Machine ◽  
Biomechanical Analysis ◽  
Careful Selection ◽  
Treatment And Prevention ◽  
Dependent Behavior ◽  
Energy Absorbing ◽  
Selection Of ◽  
Shoe Inserts

A new methodology of biomechanical analysis of materials for shoe inserts is presented. This methodology is based on the determination of the loads applied to the materials in real situations and its simulation by means of a dynamic testing machine. Both the rigidity and the energy-absorbing characteristics of the materials are investigated as a function of frequency. This methodology is applied to the study of several commercially available viscoelastic materials intended for shoe inserts in the treatment and prevention of degenerative joint diseases. The influence of thickness is investigated as well as the frequency-dependent behavior of the materials studied. Significant differences between materials and different behavior as a function of thickness and frequency were found. Poron materials were found to have the lowest rigidity, good for adequate pressure distribution, while Noene showed the highest energy absorption. A careful selection of the thickness of Sorbothane was found to be necessary for avoiding flattening of the material.

scholarly journals Mathematical Modelling of Crack Fractography after Implant Failure of Titanium 4.5 LCP Used for Flexible Bridging Osteosynthesis in a Miniature Pig

2010 ◽  
Vol 79 (4) ◽  
pp. 621-626 ◽  
Author(s):  
Alois Nečas ◽  
Lucie Urbanová ◽  
Tomáš Fürst ◽  
Pavel Ženčák ◽  
Pavel Tuček
Keyword(s):  
Mathematical Modelling ◽  
Fracture Fixation ◽  
Computer Modelling ◽  
Numerical Study ◽  
Testing Machine ◽  
Statistical Modelling ◽  
Implant Failure ◽  
Miniature Pig ◽  
Deformation Processes

Biomechanics of fracture fixation and testing of mechanical properties of bone/implant construct from the viewpoint of checking the strength and resistance ability to acting forces are of current interest. Computer modelling known as mathematical modelling is regarded as an alternative to mechanical testing of properties on a testing machine. As a result, we get a 3D model of a real object (i.e., implant for fracture fixation in our case), which can be exposed to deformation processes in the environment of the mathematical software in order to characterize forces acting on the implant and subsequently analyze the forces causing the implant failure (broken plate). The goal of this study was to employ mathematical-statistical modelling for determination of forces that caused failure (broken implant) of a five-hole titanium 4.5 mm Locking Compression Plate. This plate has been used for flexible bridging osteosynthesis of segmental femoral diaphyseal defect in a miniature pig to investigate bone healing after transplantation of mesenchymal stem cells in combination with biocompatible scaffolds. Mathematical modelling has been performed with COMSOL Multiphysics software. Numerical study that describes deformation processes taking place in implant failure demonstrates the possibilities of deformation of five-hole titanium 4.5 mm LCP in the case of exceeding the elastic limits of a material. Knowledge of the forces acting on implants used for fracture fixation acquired from mathematical modelling might be used in clinical practice in order to prevent undesirable implant failure.

A Multi-Purpose Planetary Gear Testing Machine for Studies of Gear Drive Dynamics, Efficiency, and Lubrication

1973 ◽  
Vol 95 (4) ◽  
pp. 1123-1130 ◽  
Author(s):  
R. Kasuba ◽  
E. I. Radzimovsky
Keyword(s):  
Gear Tooth ◽  
Measurement Techniques ◽  
Testing Machine ◽  
Planetary Gear ◽  
Gear Drive ◽  
Operational Characteristics ◽  
Surface Durability ◽  
Drive Dynamics ◽  
Selection Of

Feasibility of a multi-purpose testing machine for research studies in gearing has been demonstrated with construction of a unique gear testing machine with a differential planetary gear drive. This machine was used in such interdependent studies as determination of instantaneous gear tooth engagement loads, minimum film thicknesses, and gear efficiencies. With minimal structural and mechanical modifications, this gear research machine can be used for studies of surface durability, thermal distribution in gear meshing zones, and effects of variable torques and torsional oscillations on performance of gearing. Most of these studies could be conducted simultaneously. Upon selection of appropriate gear ratios, this machine was operated either with one or two stationary gears. Presence of stationary gears simplified greatly the measurement techniques and increased the reliability of tests. This machine can accommodate spur, helical or any special type of gearing. Design and operational characteristics of this machine, as well as a short summary of research projects performed on this machine, are presented in this paper.

Orbit Determination of Geostationary Earth Orbit Satellite by Transfer with Differenced Ranges between Slave-Slave Stations

2013 ◽  
Vol 67 (1) ◽  
pp. 163-175 ◽  
Author(s):  
Cao Fen ◽  
Yang XuHai ◽  
Su MuDan ◽  
Li ZhiGang ◽  
Feng ChuGang ◽  
...  
Keyword(s):  
Orbit Determination ◽  
Very Long Baseline Interferometry ◽  
Baseline Length ◽  
Positioning System ◽  
Orbit Error ◽  
Long Baseline ◽  
Data Volume ◽  
Clock Offset ◽  
Range Observation

In order to more restrict the transverse orbit error, a new method named “differenced ranges between slave stations by transfer”, similar to Very Long Baseline Interferometry (VLBI) observation, has been developed in the Chinese Area Positioning System (CAPS). This method has the number of baselines added, the baseline length increased and the data volume enlarged. In this article, the principle of “differenced ranges between slave stations by transfer” has been described in detail, with the clock offset between slave stations and system error which affects the precision of the differenced ranges observation being discussed. Using this method, the differenced observation of the SINOSAT-1 satellite with C-band between slave stations from 6 to 13 June 2005 was conducted. Then a comparison was made between the accuracy of orbit determination and orbit prediction. A conclusion can be drawn that the combination of pseudo-range receiving the own-station-disseminated signal and the differenced range observation between slave-slave stations has a higher orbit determination and prediction accuracy than using only the former.

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