Dynamic Simulation of Travelling Wave Ultrasonic Motors for Aerospace Application

2005 ◽  
Author(s):  
Simone Pirrotta ◽  
Rosario Sinatra ◽  
Alberto Meschini ◽  
Stefano Poli
Keyword(s):  
Dynamic Simulation ◽  
Development Program ◽  
Mathematic Model ◽  
Travelling Wave ◽  
Ultrasonic Motor ◽  
Space Agency ◽  
Motor Design ◽  
Italian Space Agency ◽  
Physical Features ◽  
User Friendly

In this paper a dynamic simulation of a new model for a Travelling Wave Ultrasonic Motor for antennas’ reflectors positioning, developed by Alenia Spazio S.p.A. (Roma, Italy) within an Italian Space Agency (ASI) development Program, is described. The dynamic equations for the stator and the rotors of the ultrasonic motor are assumed into a differential system, whose equations are coupled by terrms which represent interface generalized forces. Neglecting transient conditions, the complete mathematic model of the system is solved and an iterative process is developed, in order to obtain the motor’s running curves for different operation parameters, geometric dimensions and physical features of the system. The algorithm is implemented in Matlab® environment and a Graphical User Interface is constructed for user-friendly managing. This model represents a simple and powerful aid to determine final motor design that can satisfy specifications or to predict motor’s behaviour under different working conditions, as orbital ones.

Testing PRISMA hyperspectral satellite imagery in predicting soil carbon content based on synthetized LUCAS spectral data

2021 ◽  
Author(s):  
Zsófia Adrienn Kovács ◽  
János Mészáros ◽  
Mátyás Árvai ◽  
Annamária Laborczi ◽  
Gábor Szatmári ◽  
...  
Keyword(s):  
Land Use ◽  
Spectral Data ◽  
Hyperspectral Imagery ◽  
Slope Aspect ◽  
Topographic Wetness Index ◽  
Soil Carbon Content ◽  
Space Agency ◽  
Italian Space Agency ◽  
Agricultural Areas ◽  
Imagery Data

<p>The estimation of the soil organic carbon (SOC) content plays an important role for carbon sequestration in the context of climate change and soil degradation. Reflectance spectroscopy has proven to be promising technique for SOC quantification in the laboratory and increasingly from air and spaceborne platforms, where hyperspectral imagery provides great potential for mapping SOC on larger scales.</p><p>The PRISMA (PRecursore IperSpettrale della Missione Applicativa) is an earth-observation satellite with a medium spatial resolution hyperspectral radiometer onboard, developed and maintained by the Italian Space Agency.</p><p>The Pan-European Land Use/ Land Cover Area Frame Survey (LUCAS) topsoil database contains soil physical, chemical and spectral data for most European countries. Based on the LUCAS points located in Hungary, a synthetized spectral dataset was created and matched to the spectral characteristic of PRISMA sensor, later used for building up machine learning based models (random forest, artificial neural network). SOC levels for the sample area was predicted using generated models and mainly PRISMA imagery.</p><p>Our sample imagery data was generated from five consecutive, cloud-free PRISMA images covering 4500 km<sup>2</sup> in the central part of the Great Plain in Hungary, which is one of the most important agricultural areas of the country, used mainly for crops on arable lands. The images were recorded in 2020 February when most croplands are not covered by vegetation therefore our tests were implemented on bare soils.</p><p>We tested the prediction accuracy of hyperspectral imagery data supplemented by various environmental datasets as additional predictor variables in four scenarios: (i) using solely hyperspectral imagery data (ii) spectral imagery data, elevation and its derived parameters (e.g. slope, aspect, topographic wetness index etc.) (iii) spectral imagery data and land-use information and (iv) all aforementioned data in fusion.</p><p>For validation two types of datasets were used: (i) measured data at the observation sites of the Hungarian Soil Information and Monitoring System and (ii) the recently compiled national SOC maps., which provides a suitable and formerly tested spatial representation of the carbon stock of the Hungarian soils.</p><p> </p><p><strong>Acknowledgment:</strong> Our research was supported by the Cooperative Doctoral Programme for Doctoral Scholarships (1015642) and by the OTKA thematic research projects K-131820 and K-124290 of the Hungarian National Research, Development and Innovation Office and by the Scholarship of Human Resource Supporter (NTP-NFTÖ-20-B-0022). Our project carried out using PRISMA Products, © of the Italian Space Agency (ASI), delivered under an ASI License to use.</p>

Research on Dynamic Simulation of AUV Launching a Towed Navigation Buoyage

2013 ◽  
Vol 433-435 ◽  
pp. 1170-1174
Author(s):  
Guang Pan ◽  
Zhi Dong Yang ◽  
Xiao Xu Du
Keyword(s):  
Angular Momentum ◽  
Boundary Conditions ◽  
Dynamic Simulation ◽  
Numerical Scheme ◽  
Mathematic Model ◽  
Dynamic Equations ◽  
Lumped Mass ◽  
Lumped Mass Method ◽  
Towed Cable ◽  
Undersea Vehicle

A mathematic model was established to simulate the process of AUV (autonomous undersea vehicle) launching a towed buoyage. Based on the lumped mass method and moment theorem and angular momentum theorem, dynamic equations of the cable and the buoyage were developed, respectively. Then the boundary conditions and the numerical scheme to deal with the cable with non-fixed length were presented. Moreover, the process of AUV launching a towed cable was simulated. By using the model, the results show the trajectory of buoyage and shape of towed cable can be well predicted.

Study of Dynamic Simulation on Driving System and Modeling Motor for Electric Drive Application of Armored Vehicles

2014 ◽  
Vol 543-547 ◽  
pp. 286-290
Author(s):  
Zi Li Liao ◽  
Gui Bing Yang ◽  
Jia Qi Li ◽  
Ming Zhao
Keyword(s):  
Control System ◽  
Dynamic Simulation ◽  
Electric Drive ◽  
Mathematic Model ◽  
Permanent Magnet Motor ◽  
Driving System ◽  
Electric Drive System ◽  
Interior Permanent Magnet ◽  
Armored Vehicle ◽  
Interior Permanent Magnet Motor

Establish an IPM(Interior Permanent Magnet) motor mathematic model based on saturated inductance parameters. This model aimed at the traction motor of electric drive system of a certain armored vehicle. Driving control system was established on SIMULINK platform, and the consequence was analyzed.

scholarly journals Knowledge Transfer for Economic Development: Online Farmer Traning in Vojvodina

2021 ◽  
pp. 50-60
Author(s):  
Juhász Bálint ◽  
◽  
László Lengyel ◽  
Keyword(s):  
Economic Development ◽  
Knowledge Transfer ◽  
Program Implementation ◽  
Development Program ◽  
Target Area ◽  
Technical Equipment ◽  
Level Of Knowledge ◽  
The Right ◽  
Farmer Training ◽  
User Friendly

During the five-year period of the Vojvodina Economic Development Program implementation, €350 million has been invested in the target area. The aim of the present research is to review the process and achievements of farmer training and to introduce a model of successful knowledge transfer. The success of online farmer training was analyzed using statistical methods. A general model introducing a concrete practice example was developed using structural analysis and modeling. As a result of the research, we point out that improving the level of knowledge of farmers through training is a key issue in the operation of successful integration systems, in the production of crops of the right quality and quantity. Due to the fact that the design was made to be user-friendly, and requires a low-level technical equipment and IT skills, the knowledge base is equally accessible to farmers regardless of age, education and place of residence. The program expands the level of knowledge and digital competencies of the farmers, and provides useful information for further developments. The flowchart presented in the article is a suitable tool to increase the efficiency of the training today and can serve as a reference for other institutions engaged in similar activities.

Viscous Flows Formed The Branched Ridges Of Antoniadi Crater, Mars

2021 ◽  
Author(s):  
Nicolas Mangold ◽  
Livio Tornabene ◽  
Susan Conway ◽  
Anthony Guimpier ◽  
Axel Noblet ◽  
...  
Keyword(s):  
High Resolution ◽  
Imaging System ◽  
Flow Direction ◽  
Viscous Flows ◽  
Engineering Teams ◽  
The North ◽  
Space Agency ◽  
Imaging Science ◽  
Italian Space Agency ◽  
University Of Bern

<p>Antoniadi basin is a 330 km diameter Noachian basin localized in the East of Arabia Terra that contains a network of ridges with a tree-like organization. Branched ridges, such as these can form by a variety of processes including the inversion of fluvial deposits, thus potentially highlighting aqueous processes of interest for understanding Mars’ climate evolution. Here, we test this hypothesis by analyzing in details data from Colour and Stereo Surface Imaging System (CaSSIS), High Resolution Imaging Science Experiment (HiRISE) and High Resolution Stereo Camera (HRSC).</p><p>Branched ridges are up to 10 km long and from 10 to 200 m wide without obvious organization in width. The branched ridges texture is rubbly with the occurrence of blocks up to ~1 m in size and a complete lack of layering. A HiRISE elevation model shows the local slope is of 0.2° toward South, and thus contrary to the apparent network organization (assuming tributary flows). There is no indication of exhumation of these ridges from layers below the current plains surface. Our observations are not consistent with the interpretation of digitate landforms such as inverted channels: (i) The rubbly texture lacking any layering at meter scale is distinct from inverted channels as observed elsewhere on Mars. (ii) Heads of presumed inverted channels display a lobate shape unlike river springs. (iii) There is no increase in width from small branches toward North as expected for channels with increasing discharge rates downstream. (iv) The slope toward South is contrary to the inferred flow direction to the North. The detailed analysis of these branched ridges shows many characteristics difficult to reconcile with inverted channels formed by fluvial channels flowing northward. Subglacial drainages are known to locally flow against topography, but they are rarely dendritic.<strong> </strong>Assuming that deposition occurred along the current slope, thus from North to South, the organization of the network requires a control by distributary channels rather than tributary ones. Distributary channels are possible for fluvial flows, but generally limited to braiding regimes or deltaic deposits, of which no further evidence is observed here. The lobate digitate shapes of the degree 1 branches are actually more in line with deposits of viscous flows, thus as terminal branches. Such an interpretation is consistent with lava or mudflows that formed along the current topography. The next step in this study will be to determine more precisely the rheology of these unusual flows.</p><p><strong>Acknowledgments:</strong> French authors are supported by the CNES. The authors wish to thank the spacecraft and instrument engineering teams. CaSSIS is a project of the University of Bern and funded through the Swiss Space Office via ESA’s PRODEX. The instrument hardware development was also supported by the Italian Space Agency (ASI) (agreement no. I/018/12/0), INAF/Astronomical Observatory of Padova, and the Space Research Center (CBK) in Warsaw. Support from SGF (Budapest), the Univ. of Arizona (Lunar and Planet. Lab.) and NASA are gratefully acknowledged.</p>

Mapping the regional tectonic asset of the Discovery quadrangle of Mercury

2021 ◽  
Author(s):  
Valentina Galluzzi ◽  
Luigi Ferranti ◽  
Lorenza Giacomini ◽  
Pasquale Palumbo
Keyword(s):  
Imaging System ◽  
Space Environment ◽  
Fault System ◽  
Geophysical Research ◽  
Fault Systems ◽  
Space Agency ◽  
Regional Tectonic ◽  
Italian Space Agency ◽  
Dual Imaging ◽  
Map Series

<p>The Discovery quadrangle of Mercury (H-11) located in the area between 22.5°S–65°S and 270°E–360°E encompasses structures of paramount importance for understanding Mercury’s tectonics. The quadrangle is named after Discovery Rupes, a NE-SW trending lobate scarp, which is one of the longest and highest on Mercury (600 km in length and 2 km high). By examining the existing maps of this area (Trask and Dzurisin, 1984; Byrne et al., 2014), several other oblique trending structures are visible. More mapping detail could be achieved by using the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) Mercury Dual Imaging System (MDIS) imagery.</p> <p>We aim at mapping the structures of H-11 at high-resolution by using MESSENGER/MDIS basemaps, in order to understand its regional tectonic history by following the work done in the Victoria quadrangle (H-2) (Galluzzi et al., 2019). Differently from H-2, located in the same longitudinal range but at opposite latitudes, this area lacks in N-S trending scarps, such as the Victoria-Endeavour-Antoniadi fault system, which dominates the northern hemisphere structural framework. The existing tectonic theories predict either an isotropic pattern of faults (global contraction) or an ordered distribution and orientation of faults (tidal despinning) for Mercury. If we expect that the existing tectonic patterns were governed by only one of the two processes or both together, it is difficult to understand how such different trends formed within these two complementary areas. The structural study done for H-2 reveals that the geochemical discontinuities present in Mercury’s crust may have guided and influenced the trend and kinematics of faults in that area (Galluzzi et al., 2019). In particular, the high-magnesium region seems to be associated with fault systems that either follow its boundary or are located within it. These fault systems show distinct kinematics and trends. The south-eastern border of the HMR is located within H-11. Hence, with this study, we aim at complementing the previous one to better describe the tectonics linked to the presence of the HMR. Furthermore, this geostructural map will complement the future geomorphological map of the area and will be part of the 1:3M quadrangle geological map series which are being prepared in view of the BepiColombo mission (Galluzzi, 2019). <em>Acknowledgments: We gratefully acknowledge funding from the Italian Space Agency (ASI) under ASI-INAF agreement 2017-47-H.0.</em></p> <p>Byrne et al. (2014). Nature Geoscience, 7(4), 301-307.<br />Galluzzi, V. (2019). In: Planetary Cartography and GIS, Springer, Cham, 207-218.<br />Galluzzi et al. (2019). Journal of Geophysical Research: Planets, 124(10), 2543-2562.<br />Trask and Dzurisin (1984). USGS, IMAP 1658.</p>

Sign in / Sign up

Export Citation Format

Share Document