Спутник ФКИ. RAX-2. [Редактировать]

RAX-2 (Radio Auroral Explorer 2)– наноспутник, созданный студентами Мичиганского университета для исследования ионосферы. RAX-2 измеряет поток энергии в ионосферу. инамики (SDL). Каждый из них несет два ленгмюровских зонда для измерения плотности ионосферной плазмы и зонды для измерения постоянного и переменного электрических полей.

Дополнительная классификация

#Наименования
1Тип оператора(владельца) - государственный
2Страна оператор(владелец) - США
3Страна производитель - США

Информация об удачном запуске

#ХарактеристикаЗначение
1Космодром База Ванденберг
2Дата пуска2011-10-28 at 09:48:00 UTC
3Полезная нагрузка 1xNPOESS Preparatory Project
4Полезная нагрузка 1xDICE 1
5Полезная нагрузка 1xDICE 2
6Полезная нагрузка 1xRAX-2
7Полезная нагрузка 1xAubieSat -1
8Полезная нагрузка 1xE1P
9Полезная нагрузка 1xMCubed-2
10Ракета-носитель 1xДельта 2 7920

Найдено 844 документов по запросу «RAX-2». [Перейти к поиску]


Дата загрузки: 2017-04-09
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0.27/5
... sara.spangelo@jpl.nasa.gov 4. RAX MODELING............................................... 4 5. RAX ENERGY STATE & DATA COLLECTION... of the Radio Aurora Explorer (RAX) CubeSat mission. The purpose of the RAX mission is to study the... Earth and orbiting spacecraft. The RAX CubeSat model describes the configuration... models were executed for a representative RAX mission to study energy state... of ever-increasing complexity. The RAX CubeSat model will be made... an accurate model of the RAX satellite. A brief introduction to SysML... models developed for RAX are described in Section 4. RAX operational trade study... Radio Aurora Explorer (RAX) for the CubeSat project [4]. RAX is a three unit.... 3.1] SysML Diagrams Package Diagram As RAX flies along its orbit, it... stations. During each pass over, RAX performs a science experiment by receiving... signal transmitted by the radar. RAX passes through the experimental zone... Radar (ISR) located in Alaska. RAX uses a number of world-wide...-based downlink stations. The primary RAX downlink station and operations center.... 7.1.1 and A4] The modeling of RAX described in paper is this... message exchanges. [6, Para. A8] The RAX CubeSat model does not use... must support. [6. Para. A10] The RAX CubeSat model does not employ..., Sequence, and Use Case diagrams. RAX CubeSat Model Trade studies MBSE... system. Phase I [7] RAX CubeSat Model CubeSat Framework Preliminary RAX Model Availability to... Community Phase II [8] (in progress) RAX Behavior Modeling Power, Comm, and... a systems modeling development environment. The RAX CubeSat model does not contain... reference model to model RAX [7]. 4. RAX MODELING The RAX SysML model defined the... phase focused on expanding the RAX CubeSat model to include modeling behaviors [8]. This phase of the RAX CubeSat modeling supported analysis of.... Thus, the following requirements for RAX were defined: This phase of... are satisfied throughout the entire RAX mission. • • • Phase III Minimum and... the engineering analyses for computing RAX performance metrics. The following parametric... paper, focused on capturing additional RAX design and operational characteristics. A new RAX CubeSat model was developed from ... modeling how to compute various RAX states for a representative mission. This includes when RAX is in a state to collect... model the following RAX states (See Figure 9): • • • • The following RAX activities were... in a binary fashion (for example RAX is either collecting or not... an operational perspective (for example RAX can be collecting experimental data... 5 – Vehicle block definition diagram. Figure 6 - RAX system requirements are verified by... to update states of the RAX CubeSat. Figure 9 - State machine diagram... and simulations models that estimate RAX performance • Update States • Send Signals... – Use of SysML diagrams in RAX CubeSat mission simulation. 9 MagicDraw CST... tools used to execute the RAX CubeSat model. Simulation and Analytical... so that the performance of RAX can be evaluated. That’s how... compute the power collected by RAX’s solar panels using MATLAB codes..., MATLAB, and scripts in Java. 5. RAX ENERGY STATE & DATA COLLECTION ANALYSIS The integrated RAX CubeSat model was used to... energy state 10 of a nominal RAX CubeSat. The dotted line indicates... plots show that the integrated RAX model correctly models the behavior... of energy state of nominal RAX CubeSat design. 1 Values Studied Ground... of download state of nominal RAX CubeSat design. One interesting feature... planning to make available the RAX CubeSat model and associated manual... of Michigan and SRI International RAX Teams led by Professor James... his guidance in modeling the RAX satellite. We would also like... modeling approach was demonstrated for a RAX CubeSat mission by creating an..., “Initial Flight Results of the RAX-2 Satellite,” in Proceedings of the... (MBSE) Applied to Radio Explorer (RAX) CubeSat Mission Operational Scenarios,” Proceedings..., supporting the Radio Aurora Explorer (RAX) CubeSat Missions, and developing optimization...



Дата загрузки: 2017-04-09
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0.12/5
... mission, the Radio Aurora Explorer (RAX) mission, developed by the Michigan... MBSE WS. Radio Aurora Explorer (RAX) is the first National Science...) funded CubeSat science mission. The RAX missions were built by students.... We have launched two RAX spacecraft, RAX-1 and RAX-2, with the same mission objective. RAX-2 is the reference CubeSat.... The primary objective of the RAX mission is to study the... radar measurements. To overcome this, RAX utilizes a bi-static radar configuration... Scatter Radar (ISR) sites. The RAX-2 spacecraft is in a 410 by... temporal information during a 3 science experiment. RAX passes through the experimental zone... statements never can. The primary RAX ground station and operations center..., as shown in Table 1. Figure 1. RAX Mission Data Environment By formally... Modeling Framework to model the RAX mission requires the definition of a RAX Mission Element and an Earth ... are illustrated in Figure 4. The RAX Mission Element consists of a CubeSat.... Earth Orbit Environment includes the RAX Orbital Environment i.e. atmospheric density and... well as the scientific phenomenon RAX studies, FAI in the ionosphere.... 6 Figure 3. CubeSat Mission Environment Figure 4. RAX Mission Element and Earth Orbit... satellite position and attitude profile. RAX utilizes a passive magnetic stabilization system... here. 10. SPACE ENVIRONMENT FRAMEWORK RAX is a science observation mission. The... the CubeSat operates. For the RAX specific mission, gravitational and magnetic..... Figure 5. Space Environment Framework The RAX Ground System consists of a global... ground station network supporting the RAX missions consist of antennas, radios... software. Nominally, every 20 seconds, RAX beacons telemetry data, on an... send the data to the RAX team. RAX also downlinks science and... identifying the Mission Elements. For RAX-2, the Launch Service consisted of... California on October 28, 2011. RAX-2 was launched as a secondary payload... are summarized in Table 5. RAX Scenario A key RAX Mission Scenario, Collection of... Scenario. For Illustration Only. Not RAX Specific Function Inputs/Outputs Value... Determination and Control Subsystem. Not RAX Specific 16 The next steps... with Representative Physical Components. Not RAX Specific. 18 James W. Cutler received..., CA, 2008 [8] RAX Ground Station Network site http://rax.engin.umich.edu... for the Radio Aurora Explorer (RAX) Satellite Mission, the first NSF... thank the University of Michigan RAX team for their contributions. This...



Дата загрузки: 2017-04-08
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0.16/5
... to the Radio Aurora Explorer (RAX), a three-unit CubeSat developed by... phase focused on expanding the RAX CubeSat model to include modeling... and operational characteristics into the RAX model. TABLE OF CONTENTS 1. INTRODUCTION... to the Radio Aurora Explorer (RAX) [6]. RAX is a three-unit CubeSat developed... University of Michigan [10]. The RAX mission is to study the... over a ground-based radar station, RAX receives and processes the scattered... a ground station. The modeling of RAX was to prove the applicability... an accurate model of the RAX satellite. SysML has modeling elements... a methodology or tool. The Phase 1 RAX SysML model defined the logical... phase focused on expanding the RAX CubeSat model to include behaviors [7]. This phase of the RAX CubeSat modeling supported the analysis... were satisfied throughout the entire RAX mission. 2 Phase 3 teams can use... addressed the shortcomings of the RAX model in Phase 2. A new model... activity diagrams developed for the RAX mission simulation. The state diagrams... mapped to models that estimate RAX performance such as experimental data... and simulation models that estimate RAX performance Defines actions in the... 3. SysML diagrams used in the RAX mission simulation. INCOSE System Engineering... (MBSE) Applied to Radio Explorer (RAX) CubeSat Mission Operational Scenarios,” Proceedings..., “Initial Flight Results of the RAX-2 Satellite,” in Proceedings of the...



Дата загрузки: 2017-03-10
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0.14/5
... the first Radio Aurora Explorer (RAX) satellite. Launched on 20 November 2011, RAX-1 was a joint venture between the... Earth and orbiting spacecraft. The RAX mission utilized a bistatic radar configuration; the RAX spacecraft is the radar receiver... better than estimated on orbit. RAX-1 bus performance was also successful... the mission. Despite this failure, RAX-1 demonstrated that novel science is... continued development effort on the RAX mission in preparation for a late 2011 launch of a second spacecraft, RAX-2. INTRODUCTION the scattered signals with... them. The Radio Aurora Explorer (RAX) is the first of several...) to study space weather. The RAX mission is a joint effort between... currently two satellites in the RAX mission. The goal of this RAX mission is to enhance our ... initial flight results from the RAX-1 launch that occurred in late... give an overview of the RAX science mission, and briefly describe... conclude with a description of the RAX-2 launch scheduled for late 2011. RAX’s primary mission objective is to ... spacecraft. To study FAI, the RAX satellites utilize a large incoherent scatter... space. During that time, the RAX spacecraft, in low Earth orbit... their causal geophysical drivers, the RAX mission will advance the state of space weather forecasting. The RAX mission is a UHF radar experiment... amateur radio frequency bands. LAUNCH RAX was one of several payloads... bistatic radar configuration of the RAX mission. Radar pulses are reflected... by the RAX satellite. For these radar experiments, the RAX mission coordinates...-based observation [2]. See Figure 1. The RAX-1 satellite is pictured in Figure 2. Figure 2: The RAX-1 satellite fully integrated and prior... storage in the P-Pod. The RAX mission will investigate ionospheric irreguCutler... 3: The waterfall spectral plot of RAX beacons as received by a HAM.... Due to orbit perturbations, the RAX-1 then drifted into a period of... performed extremely well during the RAX-1 experiments. Noise floor characteristics were... made first contact with RAX-1 by receiving automated RAX telemetry beacons. Hank... antenna to record audio from RAX-1 beacons [3]. Richard Flagg, AH6NM, also from Hawaii, recorded RAX-1 beacons with a software-defined radio.... A student-based operations team tracked RAX-1 during its four to six... indicated strong local noise near RAX-1 UHF frequencies during the day... receiver at 500 MHz onboard RAX. It matched ground testing. The... expected. The direct (PFISR-to-RAX) radar pulses (emanating from radar.... The range delay decreases as RAX approaches the radar. The strong... of the RAX-1 receiver. Cutler Figure 5: Position information for a RAX radar experiment... Communication We provide a summary of RAX-1 bus systems, which performed nominally... was difficulty in communicating with RAX during day passes in Ann...-2400 was not operated on RAX during flight. Given the power... Attitude determination is critical for RAX mission success. To correctly characterize... and implementation characteristics of the RAX radar-receiving antenna. This need... worked as expected during nominal RAX-1 operations. Figure 7 is a plot of... actual signal reception by the RAX-1 receiver during operation over Alaska. Figure 6: A data plot generated onboard RAX during processing of a typical experiment... lock (C/N>35) relative to the RAX GPS receiver during a GPS check... an extended Kalman filter. The RAX-1 magnetometer suite consisted of two... the six faces of the RAX spacecraft compliment magnetometer measurements. These.... The blue line indicates whether RAX is in the sun or... deployment from the rocket, the RAX-1 initial rotation rates were 14... shown in Figure 10. The RAX-1 rotation dampening took longer than... Control System Attitude control on RAX-1 was a passive magnetic stabilization system... Conference on Small Satellites A second RAX satellite, shown in Figure 13... is scheduled for August 2011. RAX-2 will perform the same mission... voltage bias that destroyed them. RAX-1 maintained a positive power budget for... operations were modified to place RAX-1 into an ultra low power... power production and RAX-1 ceased operation. CONCLUSIONS The RAX mission has successfully..., and on board processing. The RAX-1 mission ended prematurely after more...-S26, June 2011. Figure 13: A RAX-2 test panel is pictured during... testing response and recovery. ACKNOWLEDGEMENTS RAX was funded by the National.... STP did a great job launching RAX, thank you! Global HAMs were instrumental in collecting RAX beacons. Thank you. Orbital Sciences... and her team in building RAX PCBs. The magnetometer calibration work..., doi:10.1029/2009JA014132. 3. WB9DWL, “RAX Hawaii -First Signal”, http:// www...



Дата загрузки: 2017-05-20
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0.13/5
... inibәlәt ısamlıdaray nıraluğruq ıcırax ülüçlö әv anığılrabite şi kәsküy ,anığılradlush... niretuypmok idrәF ŞADDAY SASƏ ŞADDAY İJİRAX kitsalE tinqam iksid remyaT niksiD... ıraluğruq şadday ksid şımlıraxıç aranәk nadnukolb metsiS .riliridşәlrib... adqıdlıxıs әdkilkәt ]neercStnirP[ uB .rılıraxıç apaç ayisamrofni ıkadnarke adqıdl... uB .rüdnükmüm .rüşürüs alos lovmis .rıraxıç anarke )rdak natut әlimamat ınarke...[ .rimşiyәd irey ıkadnarke nurosruK .rıraxıç ununumzәm ninәfihәs ıkarnos anarke... mtiroqlA .ridşimlirev nәdnifәrәt mzәraX-lӘ asuM nbi .rıdşımnaray nadnıda... әdafitsi ISAMLO ILISA NADRALUĞRUQ İCİRAX NIMARQORP SOD-SM ,ik ridt...әmlib .rınalbaseh kitamotva rәlmәc nütüb zamxıs-raxıs әfәd nadralayisknuf ıkadığaşa nәsasә nüçü qamrapa ralamalbaseh... inyE rәlәqalә adnısara rallyaf әv rılıraxıç nadrallyaf rәgid ,alqamnalxas ;runulo nim... )A ılame nınayisamrofni )B ısamnalpot nınayisamrofni )C ısamlıraxıç anarke nınayisamrofni )D ısamlınalxas imiad... әnirey inәfizәv ısnah retnirP .7 rıraxıç anarke ınayisamrofni kifarq әv ntәm )A rıyalxas... nirenakS .45 kәmte lixad әretupmok bıraxıç initәrus nınayisamrofnİ ))A kәmrev apa...әlşi nәdnifәrәt mik әfәd kli üzös ”mtiroqlA“ .1 imzәraX-lӘ asuM nbi dәmmәhuM ))A laksaP...



Дата загрузки: 2017-10-09
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0.12/5
... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . B x86 B.1 Терминология . . . . . . . . . . . . . . . . . . . . . . B.2 Регистры общего пользования . . . . . . . . . . . . B.2.1 RAX/EAX/AX/AL . . . . . . . . . . . . . . . B.2.2 RBX/EBX... в конце ф-ции main() обнуляется не RAX а EAX, т.е., 32-битная часть регистра..., 011223344h корректно запишет это значение в RAX, старшие биты сбросятся в ноль. Если... shr mov ret ENDP rax, 7653754429286296943 rcx rdx, 9 rax, rdx 0 ; 6a37991a23aead6fH Листинг...:0000000000000B46 rcl byte ptr [rsi+rax*8+29BB423Ah], 1 lea ecx, cs:0FFFFFFFFB2A6780Fh... mov rdx, 5D7E0D1F2E0F1F84h mov rax, rcx ; input imul rax, rdx mov rdx... and ecx, 0Fh ror rax, cl xor rax, rdx mov rdx, 0D2E9EE7E83C4285Bh... rol rax, cl lea r8, [rax+rdx] mov rdx, 8888888888888889h mov rax, r8... rax, rdx lea rcx, [r8+rdx*4] shl rax, 6 sub rcx, rax mov rax, r8 rol rax, cl ; EAX... rax, rbx, rcx, rdx, r8; ecx=input; rdx=0x5D7E0D1F2E0F1F84; rax=rcx; rax*=rdx; rdx=0x388D76AEE8CB1500; rax=_lrotr(rax, rax&0xF); // rotate right rax^=rdx; rdx=0xD2E9EE7E83C4285B; rax=_lrotl(rax, rax&0xF); // rotate left r8=rax+rdx; rdx=0x8888888888888889; rax=r8; rax*=rdx; rdx=rdx>>5; rax=rdx; rcx=r8+rdx*4; rax=rax<<6; rcx=rcx-rax; rax=r8 rax=_lrotl (rax, rcx&0xFF); // rotate left return rax; }; Если... rax, rbx, rcx, rdx, r8; ecx=input; rdx=0x5D7E0D1F2E0F1F84; rax=rcx; rax*=rdx; rdx=0x388D76AEE8CB1500; rax=_lrotr(rax, rax&0xF); // rotate right rax^=rdx...; rax=_lrotl(rax, rax&0xF); // rotate left r8=rax+rdx; rdx=0x8888888888888889; rax=r8; rax*=rdx... result! rax=rdx; rcx=r8+rdx*4; rax=rax<<6; rcx=rcx-rax; rax=r8 rax=_lrotl (rax, rcx&0xFF); // rotate left return rax; }; Следующий... rax, rbx, rcx, rdx, r8; ecx=input; rdx=0x5D7E0D1F2E0F1F84; rax=rcx; rax*=rdx; rdx=0x388D76AEE8CB1500; rax=_lrotr(rax, rax&0xF); // rotate right rax^=rdx; rdx=0xD2E9EE7E83C4285B; rax=_lrotl(rax, rax&0xF); // rotate left r8=rax+rdx; rdx=0x8888888888888889; rax=r8; rax*=rdx... division result! rax=rdx; rcx=(r8+rdx*4)-(rax<<6); rax=r8 rax=_lrotl (rax, rcx&0xFF); // rotate left return rax; }; Мы...=0x5D7E0D1F2E0F1F84; rax=rcx; rax*=rdx; rdx=0x388D76AEE8CB1500; rax=_lrotr(rax, rax&0xF); // rotate right rax^=rdx; rdx=0xD2E9EE7E83C4285B; rax=_lrotl(rax, rax&0xF); // rotate left r8=rax+rdx; rax=rdx=r8/60; rcx=(r8+rax*4)-(rax*64); rax=r8 rax=_lrotl (rax, rcx&0xFF); // rotate left return rax; }; Еще... rax, rbx, rcx, rdx, r8; rax=input; rax*=0x5D7E0D1F2E0F1F84; rax=_lrotr(rax, rax&0xF); // rotate right rax^=0x388D76AEE8CB1500; rax=_lrotl(rax, rax&0xF); // rotate left r8=rax+0xD2E9EE7E83C4285B; rcx=r8-(r8/60)*60; rax=r8 rax=_lrotl (rax, rcx&0xFF); // rotate left return rax; }; Простым... rax, rbx, rcx, rdx, r8; rax=input; rax*=0x5D7E0D1F2E0F1F84; rax=_lrotr(rax, rax&0xF); // rotate right rax^=0x388D76AEE8CB1500; rax=_lrotl(rax, rax&0xF); // rotate left r8=rax... rcx, aLoginFailed_us ; "login/failed_user_auto_unlock" sapgparam rax, rax short loc_1402E19DE 483 57.2. ФУНКЦИИ...



Дата загрузки: 2017-04-08
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0.09/5
... 11u1.1x 11po c 1•rnx), 0G·1,c,,.-rax 11 c111111;1'1J,\I Ol'O UM... llJl:IUOllMii 11 poc1>rnx), u r.·~c.-rax m:p110112015 II 2016 11c1wu am... IS 11 20 I Gnmou o(i'J.c1>rax i;aUUTll.IJf;HOl "O CT[)OllTCJll...



Дата загрузки: 2017-03-10
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0.07/5
... . . . . . . . . . . . . . . . . . . . . . 77 5.2.3 Science: QuakeSat . . . . . . . . . . . . . . . . . . . 78 5.2.4 Science: RAX-2 . . . . . . . . . . . . . . . . . . . . . 79 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 80 5.3.1 CP6 . . . . . . . . . . . . . . . . . . . . . . . . . . . 81... CONTENTS 5.3.2 CP5 . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 5.3.3 QuakeSat . . . . . . . . . . . . . . . . . . . . . . . . 90 5.3.4 RAX-2 . . . . . . . . . . . . . . . . . . . . . . . . . . 94 6 Conclusion 6.1 99 Validation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99... Figures 2.1 Coverage area of the RAX-2 ground station network. . . . . 8 2.2 North America... 35 4.6 Coverage area of the RAX-2 ground station network. . . . . 36 4.7 Close... window . . . . . . . . 78 5.11 RAX-2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 79 5.12 Screenshot of RAX-2 CMPT setup window... . . 92 5.25 Screen Shot of RAX-2 Print Screen . . . . . . . . . . . . . . 94 5.26 Screenshots of Percent Downlinked Plots for RAX-2 . . . . . 95 5.27 Screenshots of the... the Storage Required Plots for RAX-2 . . . . 97 xii LIST OF FIGURES... mission . . . . . . . . . . . . . 78 5.6 5.7 Parameters for the RAX-2 mission . . . . . . . . . . . . . . 79 Comparsion values for... GSI and BC methods of RAX-2 . . . 94 6.1 Comparsion of CP6 Data... the access available to the RAX-2 satellite [21]. Figure 2.1: Coverage area of the RAX-2 ground station network. 8 2.2 CubeSat Communications... mission description of RAX-2. To study FAI, the RAX mission will utilize... space. During that time, the RAX spacecraft will be orbiting overhead... in the Ionosphere [27] with RAX 1 and 2, or GeneSat-1’s onboard micro...]. ❼ Full World Ground stations The RAX-2 network was the model for.... The most up to date RAX-2 network is on their shared... Figure 4.6: Coverage area of the RAX-2 ground station network. no profit... such as those flown in RAX 1 and 2 utilize 7V4 raw bus... with a single ground station, and RAX-2 for the science case with... network. Mission CP6 CP5 QuakeSat RAX-2 Type Initial Attempt One-Shot... 78 5.2 Real World Cases 5.2.4 Science: RAX-2 RAX is a joint venture between the... known to disrupt communica- Figure RAX-2 tion between Earth and orbiting... 437 MHz [48] Full World RAX Ground Station Client Table 5.6: Parameters for the RAX-2 mission Figure 5.12: Screenshot of RAX-2 CMPT setup window 79 5.11: 5. ... used in comparsion with the RAX mission to show the superior... 5. CASE STUDIES 5.3.4 RAX-2 Figure 5.25: Screen Shot of RAX-2 Print Screen Percent... GSI and BC methods of RAX-2 94 5.3 Results (a) GSI (b) BC Figure... of Percent Downlinked Plots for RAX-2 Percent of Data Downlinked with... of the ways that the RAX team overcame this issue was... of Ground Station Initiation for RAX-2 As with previous uses of... the Storage Required Plots for RAX-2 Storage Required for Ground Station...] J. Bluck. GeneSat-1. 21, 27 [27] Rax Mission Overview. 23, 27, 79... Tisat‐1 Minotaur IV, Nov 2010 RAX Passive magnetic attitude control,  GPS... Romania University of Vigo M‐Cubed RAX‐2 VEGA Launch, Feb 2012 MaSat... The primary objective for the RAX  mission is to study the... the space‐based  receiver onboard RAX to measure  FAI intensity, altitude...



Дата загрузки: 2017-03-18
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0.23/5
... position of the vacuum field (Rax). The finite plasma effect and... the plasma EX/5-4Rb 2 of Rax=3.6 m, the magnetic shear tends to... ~3 %. We have scanned the parameters Rax, and Ip for the study... types of magnetic configuration: (i) low (<1 %), Rax=3.6 m plasma with high magnetic shear, (ii) low (<1 %), Rax=3.5 m plasma with medium magnetic shear, and (iii) high (>2 %), Rax=3.6 m plasma with weak magnetic shear... Fig. 1. 2.1. Configuration (i): High Magnetic Shear (Rax=3.6m, low ) In the configuration...-injected into a helium plasma at Rax=3.6 m and magnetic field strength Bt... TAE gap frequencies (f TAE=vA /4 Rax: dotted and broken curves) shown... observed in the plasma of Rax=3.6 m with high magnetic shear (configuration... 4 2.2. Configuration (ii): Medium Magnetic Shear (Rax=3.5, low ) In the configuration (ii... is smaller than that of Rax=3.6 m (configuration (i)), a number of TAE with... of each modes. The of Rax=3.5 m with medium magnetic shear (case... ~0.4. 2.3. Configuration (iii): Low Magnetic Shear (Rax=3.6 m, high ) In the configuration (iii... even in the configuration of Rax=3.6 m, a number of bursting TAE are...///vA in the configurations of Rax=3.6 m and 3.5 m, changing various plasma parameters... m~3/n=2 G-TAEs in configuration of the Rax=3.6 m (blue circle) and 3.5 m (red circle... with n=1,2,3 in configuration of the Rax=3.6m and Bt >0.75 T. EX... the condition of 0.3 >0.05 % for Rax=3.6 m plasma (configuration (i) and (iii)), and 0.3 >0.01 % for Rax=3.5 m plasma (configuration (ii)), respectively. This... threshold of m~3/n=2 G-TAEs in the Rax=3.5 m and Rax=3.6 m plasmas seems to be... damping of m~3/n=2 G-TAEs in the Rax=3.6 m plasmas are higher than that in the Rax=3.5 m plasmas, because the magnetic shear at edge of Rax=3.6 m plasma is larger than that in Rax=3.5 m plasma. The HAEs are only observed in the configuration of Rax=3.6 m and >2 %. The HAEs with n=1~3 are...



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0.14/5
... Attitude Control System for the RAX Nanosatellite* G. Park∗ and S. Seagraves∗ Department... controlled attitude dynamics of the RAX nanosatellite, along with numerical simulations... (N − m) moment of inertia of the RAX nanosatellite expressed in the body... attitude dynamics model for the RAX nanosatellite that incorporates a passive magnetic... magnetic control approach for the RAX nanosatellite. The NSF sponsored Radio Aurora Explorer (RAX) project currently underway at the... actual mission data. B. RAX Mission Overview The RAX nanosatellite has been commissioned... at California Polytechnic State University. RAX is a triple configuration (3U) CubeSat... release from the P-POD, the RAX nanosatellite enters a circular orbit with...’s magnetic field. A schematic of the RAX nanosatellite is shown in Figure... shown. Figure 1. Schematic of the RAX nanosatellite 2 of 18 American Institute... necessary for success of the RAX mission. Although prior spacecraft missions... not a realistic assumption for the RAX nanosatellite but it provides insight... investigations progress. We assume the RAX nanosatellite is in a circular orbit... arbitrary rotational motion of the RAX nanosatellite and for arbitrary direction... the Earth’s magnetic field at RAX’s location on its orbit. B. Reference... represent the attitude of the RAX nanosatellite, several different reference frames... defining the attitude of the RAX nanosatellite, by providing the relationship... R˙IB + S(ω)RIB = 0 (3) J ω˙ + ω × Jω = M (4) where J is the RAX moment of inertia matrix and... skew-symmetric matrix is   0 ω3 −ω2   S(ω) =  −ω3 (5) 0 ω1  . ω2 −ω1 0 The RAX nanosatellite has an axis of... Torques on the RAX Magnetic stabilization of the RAX attitude motion is... within the RAX structure. A permanent magnet is embedded in RAX with its... of Aeronautics and Astronautics the RAX second principal axis. Thus the... Earth’s magnetic field at the RAX location. 2. Torques due to Hysteresis... attitude dynamics equations for the RAX. The subsequent development assumes that... Earth’s magnetic field at the RAX location. F. Summary of Attitude Equations... attitude control system for the RAX attitude dynamics. The Euler equations...) Initial Value Problems for the RAX Attitude Dynamics The above equations... attitude dynamics model for the RAX is physically meaningful. This initial... makes formal analysis of the RAX attitude dynamics difficult. Several results... above model for the RAX attitude dynamics. A. RAX Attitude Dynamics in an... magnitude and direction along the RAX orbit. Several theoretical results for this case are summarized. 1. RAX Relative Equilibrium Solutions It can... the pointing directions of the RAX nanosatellite corresponding to these two... a rotation of π radians. 2. Stability of RAX Relative Equilibrium Solutions We now... results stated here. B. Analogy between RAX Attitude Dynamics and Dynamics of... field. The first class of RAX relative equilibrium solutions is analogous... velocity about that principal axis. C. RAX Attitude Dynamics in a non-Equatorial... orbits are planned for upcoming RAX missions. Nevertheless, the analytical results... orbits. Along non-equatorial, circular RAX orbits, there are no equilibrium... the above results for the RAX attitude dynamics, assuming a constant Earth... asymptotic stability property: almost all RAX attitude motions asymptotically approach one... difficulty of analyzing such complex RAX attitude motions provides motivation for... dynamics of the magnetically controlled RAX nanosatellite in non-equatorial circular... group variational integrator If the RAX nanosatellite were not to include... rotation matrices that characterize the RAX attitude. Both of these factors... will increase significantly after several RAX orbits, thereby invalidating the attitude... computed simulation results for the RAX attitude dynamics are accurate, even... orbit at several different inclinations. 1. RAX Simulation Assumptions The orbital specifications for the RAX nanosatellite are as follows. The... of inertia matrix of the RAX nanosatellite is J = diag(2.91058; 2.91058... each point along the RAX orbit. The RAX orbit position vector should... develop suitable plots for the RAX rotational motion. Four different sets... provided. Scenario 1 assumes that the RAX is in a zero degree inclination... and Astronautics 2. Simulation Scenario 1 The RAX attitude motion is simulated for... of 0.0 degrees 3. Simulation Scenario 2 The RAX attitude motion is simulated for... conditions correspond to an inaccurate RAX deployment for which the initial... of 0.0 degrees 4. Simulation Scenario 3 The RAX attitude motion is simulated for... initial angular velocity of the RAX is ω(0) = 0.0 0.0 0.0 rad/sec (49) The... 72.0 degrees 5. Simulation Scenario 4 The RAX attitude motion is simulated for... conditions correspond to an inaccurate RAX deployment for which the initial... dynamics of the RAX nanosatellite. The model assumes RAX is in a low... field; theoretical implications for the RAX attitude dynamics in the case... passive magnetic attitude control. The RAX attitude dynamics are dominated by...