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    Mark ZimmermanTypewritten Texthttp://www.ATIcourses.com/schedule.htmhttp://www.aticourses.com/Fundamentals_Of_Space_Systems_Space_Subsytems.htm

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    Mark ZimmermanTypewritten TextCourse Schedule:Course Outline:

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    Mark ZimmermanTypewritten TextSPACE SYSTEMS AND SPACE SUBSYSTEMS - FUNDAMENTALS

    Mark ZimmermanTypewritten Text

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    Mark ZimmermanTypewritten TextInstructor:

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    Mark ZimmermanTypewritten TextDr. Vincent L. Pisacane

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  • www.ATIcourses.com

    Boost Your Skills with On-Site Courses Tailored to Your Needs The Applied Technology Institute specializes in training programs for technical professionals. Our courses keep you current in the state-of-the-art technology that is essential to keep your company on the cutting edge in todays highly competitive marketplace. Since 1984, ATI has earned the trust of training departments nationwide, and has presented on-site training at the major Navy, Air Force and NASA centers, and for a large number of contractors. Our training increases effectiveness and productivity. Learn from the proven best. For a Free On-Site Quote Visit Us At: http://www.ATIcourses.com/free_onsite_quote.asp For Our Current Public Course Schedule Go To: http://www.ATIcourses.com/schedule.htm

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  • Pisacane, 2013

    CASSINI-HUYGENS Interplanetary Mission to Saturn

    Saturn surrounded by Rings and 62 Moons Cassini launched in October 1997 arrived at Saturn June 2004 The mission has been extended through September 2017

  • Pisacane, 2013

    Planned 6 Oct

    Planned 20 June

    Planned 16 August

    @ 1,170 km

    Planned 1 Dec

    Planned 21 April

    Planned 30 Dec 2000

    Planned 1 July

    CASSINI-HUYGENS Trajectory

  • Pisacane, 2013

    NEAR Configurations

  • Pisacane, 2013

    RISK MANAGEMENT NASAs Approach to Risk Management

    NASA identifies two activities critical to risk management

    Risk-Informed Decision Making (RIDM) Selection of alternatives based on assessment of requirements including risk

    Continuous Risk Management (CRM) Systematic identification, assessment, and management of all risks

    From: NASA Risk-Informed Decision Making Handbook, NASA/SP-2010-576 Version 1.0 Apr 2010

  • Pisacane, 2013

    SYSTEM DEVELOPMENT NASA Project Life Cycle Reviews

  • Pisacane, 2013

    SYSTEM TESTING Sample NASA Payload Test Requirements

    From: NASA-STD-7002A Payload Test Requirements

  • Pisacane, 2013

    SPACECRAFT FAILURES NOAA Spacecraft Radiation Induced Failures May 1998

    Data from NOAA GOES (Geostationary Operational Environmental Satellite) constellation

    Equator-S failure attributed to latch-up in central processor as result of a week or more of elevated relativistic electron (top figure)

    POLAR processor loss of 6 hours of data attributed to

    single-event upset (SEU) in processor from increased proton flux (bottom figure)

    Galaxy 4 processor failure likely caused, by the energetic electron environment most likely due to deep dielectric, (or bulk) charging (top figure)

    Space Environmental Conditions During April and May 1998: An Indicator

    for the Upcoming Solar Maximum

    D.N. Baker, J.H. Allen, S. G. Kanekal, and G.D. Reeves

  • Pisacane, 2013

    The standard life test for flight hardware parts is the dynamic (power on) burn-in test for 1000 hours (41.7 d) at an ambient temperature of 125oC (257oF)

    The Acceleration Factor (Af) is the test time multiplier derived from the Arrhenius equation for operation at another temperature

    Activation energy (Ea) is an empirical value of the minimum energy required to initiate a specific type of failure mode that can occur within a technology type Failure modes include: oxide defects, bulk silicon defects, mask defects, electro-

    migration, and contamination

    Typical values of Ea for electronic devices are 0.5-1.0 eV, typically > 0.7

    Table shows acceleration factors and equivalent durations

    Ea, eV

    Acceleration Factors For use temperatures

    Equivalent Duration, y

    25oC 77oF

    35oC 95oF

    45oC 113oF

    25oC 77oF

    35oC 95oF

    45oC 113oF

    0.5 133 71 39 15 8 2

    0.6 353 165 81 40 19 9

    0.7 938 387 169 107 44 19

    0.8 2,492 907 352 284 103 40

    0.9 6,624 2,125 732 756 242 84

    1.0 17,607 4,979 1,524 2,008 568 174

    FAILURE ANALYSES Burn-in Tests at Elevated Temperatures

    testuse

    af

    T

    1

    T

    1

    k

    EexpA

    Parameters Ea = Activation Energy of the failure mode, eV k = Boltzmann's Constant, 8.617 x 10-5 eV K-1

    Tuse = Use Temperature, K Ttest = Test Temperature, K

    testusef

    testusef

    T Tif 1AT Tif 1A

  • Pisacane, 2013

    Failure Modes, and Effects Analysis (FMEA)

    System: Part Name Reference Drawing Mission

    Date Sheet X of X

    Compiled by: XXXX Approved by: XXXX

    Item

    Function or

    Require-ment

    Potential Failure Modes

    Potential Causes

    of Failure Mode

    Potential Effects of Failure Mode

    Detection and

    Mitigating Factors

    O c c u r r e n c e

    D e t e c t i o n

    S e v e r i t y

    RPN Actions

    Recomm- endations

    Respon- sibility Local

    Effects

    Inter-mediate Effects

    End Effects

    Battery

    Provide adequate

    relay voltage

    Fails to provide

    adequate power

    Voltage drops to

    zero

    Battery plates

    shorted

    Instrument not

    functional

    Mission Aborted

    Test battery prior to launch

    4 4

    0.5+

    0.3 X5 = 4

    64 XXX XXX

    FAILURE IDENTIFICATION Sample FMEA Worksheet Failure Modes and Effects Analysis (FMEA)

    Typical FMEA worksheet is illustrated below for a spacecraft battery

  • Pisacane, 2013

    RELIABILITY, AVAILABILITY, MAINTAINABILITY, and SAFETY Derating Introduction

    Derating increases the margin of safety between operating stress level and actual failure level for the part, providing added protection from unanticipated anomalies

    Derating is employed in electrical and electronic devices, wherein the device is operated at lower than its rated maximum power dissipation, taking into account Case/body temperature Ambient temperature Type of cooling mechanism

    When derating, the application engineer applies a recommended derating factor bases on the part specifications and operating environment

    For microcircuits, major derating factors are Supply voltage Power dissipation Signal input voltages Output voltages Output currents

  • Pisacane, 2013

    Series redundancy Reliability Rs of the series chain is given

    by

    If all components have the same reliability then Ri = R and

    Parallel redundancy The reliability of a parallel configuration

    if only one device is needed is

    If all component s have the same reliability then Ri = R and

    RELIABILITY, AVAILABILITY, MAINTAINABILITY, and SAFETY Calculating Reliabilities

    n

    sRR

    n21

    n

    1iis

    R1R1R11R11R

    n321

    n

    1iis

    RRRRRR

    ns R11R

  • Pisacane, 2013

    CELESTIAL MOTION Principal Motion of the Celestial Ephemeris Pole

    (more accurate number is 25,780 yrs)

    (average of 50.26 sec of arc per year or 0.1376 sec arc per day)

  • Pisacane, 2013

    COORDINATED UNIVERSAL TIME (UTC) Variation in the Length of Day 2/2

    From: http://www.ucolick.org/~sla/leapsecs/dutc.html

    25

  • Pisacane, 2013

    REFERENCE SYSTEM Geometrical Transformation Between GCRS and ITRS

    Figure shows transformation between terrestrial (ITRS) to celestial (GCRS) taking into account (1) Pole Movement, (2) Earth Rotation , (3) Precession and Nutation GCRS= Geocentric Celestial Reference System ITRS = International Terrestrial Reference System CIP = Celestial Intermediate Pole, instantaneous Earth spin axis CTP = Conventional Terrestrial Pole, reference pole in ITRS (now average of pole positions from 1900 to 1905)

    Modifiedfrom:ESA,http://navipedia.org/index.php/Transformation_bet

    ween_Celestial_and_Terrestrial_Frames

  • Pisacane, 2013

    GRAVITATIONAL POTENTIAL Geometrical Representation of Spherical Harmonics

    m = 0 no longitudinal

    variation

    n m and m 0 Tessarae (Tiles)

    n = m no latitudinal

    variation

    n = 2, m = 2 n = 3, m = 3 n = 5, m = 0 n = 4, m =3

    Pn,m(Cos q) Cos m(l l n,m) has (nm) sign changes or zeros 0 q p (latitude of 180 degrees 2m zeros in interval 0 l < 2p (longitude of 180 degrees)

  • Pisacane, 2013

    TRAJECTORY PERTURBATIONS Mars Global Surveyor Aerodynamic Braking

  • Pisacane, 2013

    ROCKET PROPULSION Specific Impulse vs Thrust

    From: http://dawn.jpl.nasa.gov/mission/images/CR-1845.gif

    NH3 = Ammonia

    N2H4 = Hydrazine

    Grayed area are

    realized

    characteristics

  • Pisacane, 2013

    ROCKET PROPULSION de Laval Nozzle

    The function of the nozzle is to convert the chemical-thermal energy produced in the combustion chamber into kinetic energy

    Thrust is the product of mass time velocity so a very high gas velocity is desirable

    The nozzle converts slow moving, high pressure, and high temperature gas in the combustion chamber into high velocity gas of lower pressure and temperature at the nozzles exit

    De Laval nozzles consist of a convergent and divergent section

    The section with minimum area is the nozzle throat

    The nozzle is usually made long enough and the exit area large enough to reduce the high pressure in the combustion chamber to the ambient pressure at the nozzle exit to create maximum thrust

    Typical DeLaval nozzle

    T = temperature

    p = pressures

    v = speed

    M = Mach number

    From: http://en.wikipedia.org/wiki/Rocket_engine

  • Pisacane, 2013

    LAUNCH FLIGHT MECHANICS Available Launch Inclinations in the United States

    37

    114

  • Pisacane, 2013

    COLD GAS PROPULSION SYSTEMS Typical Cold Gas System Implementation

    L L L L

    GN2

    L

    P T

    F

    P

    T

    P

    T

    P

    T

    P

    T

    Latch Valve

    Temperature sensor

    Pressure Sensor

    Pyrovalve

    normally open

    Pyrovalve

    normally closed

    Burst Valve

    Latch Valve

    Gas Regulator

    Filter

    Service valve

    Access Port

    L

    P

    T

    F

    NO

    NC

    L

    Check Valve, arrow

    direction of flow

    Typical cold gas thruster

    Propellants

    Air, Carbon Dioxide,

    Helium, Hydrogen,

    Methane, Nitrogen, Freon

  • Pisacane, 2013

    LIQUID PROPULSION SYSTEMS Messenger Spacecraft Dual Mode Propulsion

    S Wiley, K Dommer, L Mosher, Design and development of the

    Messenger propulsion system, AIAA, PRA-053-03-14 July 2003

    Illustrates the Messenger spacecraft propulsion system with 17 thrusters

    Bipropellants Hydrazine (N2H4) and Dinitrogen Tetroxide (N2O4)

    Monopropellant Hydrazine (N2H4)

  • Pisacane, 2013

    TRANSFER TRAJECTORIES Apollo 13 Circumlunar Free-Return Trajectory

    CSM Command Service Module, DPS Descent Propulsion System EI Entry Interface GET Ground Elapse Time LM Lunar Module MCC Mid-Course Correction PC Pericynthion (closest point to moon) S-IV4B Saturn IVB SM Service Module TLI Trans Lunar Injection

    JL Goodman , Apollo 13 Guidance, Navigation, and Control Challenges AIAA SPACE 2009 Conference & Exposition, Sept 2009, Pasadena,, AIAA 2009-6455

  • Pisacane, 2013

    OVERVIEW Attitude Control Schematic

  • Pisacane, 2013

    ATTITUDE KINEMATICS Quaternion Mathematics 1/2

    Addition and subtraction Elements are added or subtracted

    Multiplication Not communicative, Q1Q2 Q2Q1 Multiple each component

    where

    Equivalent quaternions Reversing signs on all 4 elements yields an equivalent quaternion

    Q = Q

    time

    s 1 i j k

    1 1 i j k

    i i 1

    k j

    j J k

    1 i

    k k j i 1

    4,23,22,21,24,13,12,11,121

    qkqjqiqqkqjqiqQQ

    4,24,13,23,12,22,11,21,1 qqkqqjqqiqq

    4,23,22,21,24,13,12,11,121

    qkqjqiqqkqjqiqQQ

  • Pisacane, 2013

    ATTITUDE SENSORS ADCOL Two-Axis Digital Sun Sensor System

    http://adcole.com/two-axis-dss.html

    Two-Axis Digital Sun Sensor System No of measurement axes:

    2 each sensor) Number of sensors

    5 typical per electronics 1 to 8 sensors can also be used Electronics selects sensor that has

    sun in field of view

    Heritage Many systems flown with 1 to 8 sensor

    heads per processing electronics

    Parameters Field of view: 64 x 64

    Note: 4 steradians (full sphere) coverage can be achieved with 5 sensors.

    Accuracy: 0.25 (transition accuracy). Least Significant Bit Size: 0.5 Sign bit

    Most significant bit

    Least significant bit Interpolating bits

  • Pisacane, 2013

    INTRODUCTION Function and Components of Spacecraft Power System

    Power system functions Supply electrical power to spacecraft loads Distribute and regulate electrical power Satisfy average and peak power demands Condition and convert voltages Provide energy storage for eclipse and peak demands Provide power for specific functions, e.g., firing ordinance for mechanism

    deployment Ensure power to critical loads during critical phases and spacecraft anomalies Ensure power for mission duration

    Primary Power

    Source

    Energy

    Conversion

    Power

    Regulation

    Power

    Distribution

    Power

    Regulation

    Energy

    Storage

    Power

    Regulation

    Critical

    Loads

    Non-Critical

    Loads ?

  • Pisacane, 2013

    SECONDARY BATTERIES Candidate Technologies

    http://www.clyde-space.com/products/spacecraft_batteries/useful_info_about_batteries/secondary_batteries

  • Pisacane, 2013

    SOLAR ARRAYS Solar Array Construction

    Cells connected in series to achieve desired voltage

    Cells connected in parallel to achieve desired power

    Arrays organized to minimize current loops that result in dipole moment

  • Pisacane, 2013

    OVERVIEW NEAR Spacecraft Spacecraft Communication System

    From: RS Bokulic, MKE Flaherty, JR

    Jensen, and TR McKnight, The NEAR

    Spacecraft RF Telecommunications System,

    Johns Hopkins APL Technical Digest, Vol

    19, No 2 (1998)

    Transponder unifies a number of communication functions - receiver,

    command detector, telemetry modulator, exciters, beacon tone

    generator, and control functions

    Diplexer is a device that can split and combine audio and video

    signals

  • Pisacane, 2013

    ANTENNAS Typical Parabolic Antenna Pattern

  • Pisacane, 2013

    LINK ANALYSIS Example Link Analysis

    dB3.38683

    400

    1000

    1011038.1

    63.097.01058.15.076.768.020

    T

    G

    kR

    LLEIRP

    N

    E623

    116

    s

    RA

    b

    a

    LossesOther

    a

    s

    0

    b

    Transmitter power 20 W +13.0 dBW

    Spacecraft cable loss 1dB 1 dB

    Antenna boresight

    gain 76.76 +18.9 dB

    EIRP 30.9 dBW

    Antenna beamwidth 3 dB 3.0 dB

    Space loss at 10o

    elevation @ 3000 km 1.58 x 1016 162.0 dB

    Pointing error, 0.1 BW 0.12 dB 0.12 dB

    Atmospheric loss 0.1 dB 0.2 dB

    Receiver G/T 1000/400 K-1 4.0 dbK-1

    Boltzmann constant,

    k

    1.38x10-23

    JK-1 +228.6 dB J-

    1K

    Bit rate 106 bps 60 dB s

    Receiver Eb/No 38.2dB

    76.7610x3

    10x1170.0

    c

    DfG

    2

    8

    92

    boresight

    Spacecraft antenna diameter = 1 m Frequency = 1 GHz Pointing error= 1/10 beamwidth Receiver gain = 30 dB Receiver system temperature = 400K Bit rate = 106 bps

    16

    2

    8

    962

    l

    s1058.1

    103

    1011034

    c

    rf4L

    p

    p

    dB12.01.012dB12L2

    2

    dB3

    dB3

    i

    2

    i2

    dB3

    l q

    qq

    q

    q

  • Pisacane, 2013

    THERMAL ANALYSES Analysis Process

  • Pisacane, 2013

    MULTILAYER INSULATION Gold and Black MLI

    Gold Thermal Blanket Outer layer is of a second surface mirror material with

    high reflectivity and high emittance Consists of multiple layers of silver coated Kapton film

    that gives it a gold color Except outer layers, all are perforated to allow entrapped

    air to escape during launch and separated by a Dacron netting Edges are finished with a tape prior to sewing Individual blankets held together and to spacecraft by

    dacron Velcro

    Black Thermal Blanket Black thermal blanket is used on the shade side of the

    spacecraft Identical to the gold blanket except for the outer layer

    generally Kapton filled with carbon powder Outer layer has a higher absorptance and lower

    emittance than the gold Kapton This layer is also electrically conductive because of

    carbon fill Grounding outer layer to the spacecraft frame dissipates

    any charge build

    Gold is multilayer insulation of

    Cassini spacecraft; from

    NASA

    New Horizons spacecraft

    http://www.boulder.swri.edu/pkb/ssr/ssr-

    fountain.pdf

  • Pisacane, 2013

    DESIGN PROCESS Overall Development Flow Chart

    Spin Balance and Environmental

    Testing

    Preliminary Launch Loads

    Preliminary Natural Frequency Constraints

    Thermal Analysis

    Temperature Distribution

    Structural Analysis Finite Element Model Dynamic Analysis Stress Analysis Thermal Distortion Assess Margins

    Launch Vehicle Dynamic Model and

    Forcing Functions

    Coupled Launch Vehicle and

    Spacecraft Dynamic Analysis

    Spacecraft Dynamic

    Model

    Spacecraft Dynamic Response

    Loads Acceleration

    Functional Subsystem/Payloads

    Requirements

    Preliminary Spacecraft Structural

    Design

    Fabricate Spacecraft Structure

    Launch Vehicle Constraints

    Spacecraft Structural Configuration

    Conceptual and

    Preliminary

    Design

    Critical Design

    Fabrication

    Integration

    launch

    start

  • Pisacane, 2013

    STRUCTURAL CONFIGURATIONS Structural Categories

    Structural components are categorized by the different types of requirements, environments, and methods of verification that drive their design Primary structures are usually designed to survive steady-state accelerations and

    transient loading during launch and for stiffness Secondary and tertiary structures are usually designed for stiffness, positional

    stability, and fatigue life

    Primary structures: body structure launch vehicle adapter

    Secondary structures: appendage booms support trusses platforms solar panels Antenna Extendibles

    Tertiary structures: brackets electronics boxes

  • Pisacane, 2013

    INTRODUCTION Space and Ground Based Systems

    Reliability, complexity, development costs, and operational costs are affected by the partitioning of the computational load between the space and ground segment

    From Wertz and Larson

  • Pisacane, 2013

    COMPUTER COMPONENTS Typical Spacecraft Computer Schematic

    Figure is a simplified block diagram of a spacecraft computer system

    One or more processing units have access through bus structures to Read only memory, random access memory, and special purpose memory Mass storage Input/output ports to spacecraft subsystems and payloads Spacecraft communication system Numerical coprocessor to carry out floating point arithmetic faster

    From Pisacane, Fundamentals of space systems, Oxford University Press,

    2005

  • Pisacane, 2013

    FAULT TOLERANCE Summary Fault Tolerant Techniques

    NMR = n-modular redundancy ECC = Error Correction Coding RESO = RE-computing with Shifted Operands; computation carried

    out twice - once with usual input once with shifted operands Self-purging = each module has a capability to remove itself from

    the system if faulty Recovery blocks = Uses the concept of retrying the same

    operation and expect the problem is resolved by the second or later tries

  • Pisacane, 2013

    SPACECRAFT PROCESSORS RAD6000 Processor

    Characteristics 35 Mbps at 33 MHz Radiation Hardened 32-bit RISC Super Scalar Single Chip CPU 8K Byte Internal Cache Simplex or Dual Lock-step (compares CPU

    operations) Low Power 3.3 Volt Operation 72-bit (64 Data, 8 ECC) Memory Bus Variable Power/Performance Independent Fixed and Floating Point Units

    Radiation Hardness Levels Total Dose: 2x106 rads(Si) Prompt Dose Upset: 1x109 rads(Si)/sec Survivability: 1x1012 rads(Si)/sec Single Event Upset: 1x10-10 Upsets/Bit-Day Neutron Fluence: 1x1014 N/cm Device Latchup: Immune

    From Lockheed Martin Federal Systems RAD6000 Radiation Hardened 32-Bit

    Processor

    atc2.aut.uah.es/~mprieto/asignaturas/satelites/pdf/rad6000.pdf

    COP = Common on-chip processor interface

    FPGA = Field Programmable Gate Array

    HMC = Hardware Management Console

    RS232 = Serial binary single ended data connector

    VME bus = VersaModular Eurocard bus

    Dual Lock Step

    A technique that achieves high

    reliability by adding a second

    identical processor that monitors and

    verifies the operation of the system

    processor

  • Pisacane, 2013

    INTEGRATION AND TEST PROCEDURES Integration and Test Procedure

    From Spacecraft Computer Systems, JE Keesee ocw.mit.edu/courses/aeronautics-and.../l19scraftcompsys.pdf