Mission Overview

Goldeneye

University of MinnesotaUniversity Nanosat 5

PDR Presentation

August 16th-17th, 2007Logan, Utah

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Mission Overview

Mission StatementThe purpose of Goldeneye is to design, construct and validate a GPS bistatic radarfor remote sensing applications onboard small satellites in low Earth orbit.

Mission Objectives• Obtain Earth reflected GPS signals→• Obtain direct GPS signals• Process acquired data on the ground

Technology Demonstration• Multifunctional applications• Advanced science instrumentation and detector/camera technology• Advanced solutions for miniaturized Nanosat subsystems

– Innovative GPS receiver/antenna, hardware, and algorithms

GoldeneyeGPS Satellite

Earth-reflected GPS signal

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Bistatic Radar : Transmitter is not the receiver as in monostatic radar• Transmitter is the GPS satellite• Receiver is Goldeneye

• a is the range between transmitter and receiver• b + ρ is the reflected signal• From the geometry the range, ρ, to the reflection surface can be found

By analyzing the reflected signals power, Doppler shift and range variation, information about the reflecting surface can be deduced.

The science in this mission is to correlate these reflected signals with known ocean conditions, atmospheric and land conditions thereby exploring this novel application of GPS.

Example of Doppler-Shift vs Range Variation from a Reflected GPS Signal. ( S. Gleason, Remote Sensing of Ocean, Ice and Land Surfaces Using Bistatically Scattered GNSS Signals. Ph.D. Thesis. Surrey University. 2006.)

Mission Details: Bistatic Radar

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Mission Timeline• Baseline mission: duration - TBD• Startup:

– Automatically enabled– Ends when pointing requirements satisfied

• Baseline Mode:– Continuously runs after startup– Includes “life support” systems only– Charges batteries– Receives messages from ground station– Sends health status reports to ground

station• Attitude Control Mode:

– Detumbles Goldeneye– Despins Goldeneye– Points GPS high gain antenna towards

Earth• Experiment Mode:

– Collects GPS data– Compresses GPS data– Stores GPS data

• Transmit Data Mode:– Transmits experiment data to ground

station for post processing• Extended Operations

RISK

Startup (duration - TBD):

Integrate with launch

vehicleLaunch Deploy

Inhibits release

Charge batteries4 hours

Baseline Mode

6 hours*

Experiment Mode

36 sec.

Transmit Data Mode

10 min.

Normal Operations Modes (duration - TBD):

Test payload

Ground:

Attitude Control Maneuvers:

· Detumble· Despin about z-axis· Point GPS high gain

antenna towards earthTBD

Activate systems5 min.

Verify systems15 min.

Attitude Control ModeTBD

*Maximum time needed to completely recharge

batteries while operating baseline components

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Program ScheduleRISK

• Purpose: Ensure project is completed on-time• Objective: Meet and verify requirements

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Mission Top-Level Details: Remote Sensing with GPS

Minimum Success: • Establish Orbit• Acquire direct and reflected GPS signals for at

least 36 seconds• Transmit GPS data to ground station• Post-process GPS data• Detect surface conditions on Earth

– Ocean wind speed – Wave/tidal height

Nominal Success:• Minimum success criteria met• Detect additional surface conditions on Earth

– Ice surfaces– Land features– Soil moisture content

Another Possibility:• Collect reflected GPS signals from other objects

in orbit· Analysis for the possibility of detecting other objects has

been done.· Radar cross section of reflecting object must meet

certain stringent requirements (specular reflector, larger than 30 cm, etc)

RISK

Stephen Forbes

Each Mission Statement should have a paragraph explaining what it is and why do it in more detail

Scott Franke

Scott Franke --This slide will be a mission selling slide to those who want the top-level data, but don't have time to go farther into the charts. The paragraphs will correspond to each different objective you break out from the mission statement.

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Mission Top-Level Details: GPS Navigation Message

Figure adapted from, Misra and EngeGlobal Positioning System:Signals, Measurements and Perfomrancepp. 104, which is based on a figure by Frank van Diggelen

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Requirements FlowMission Statement

Mission Objectives

Minimum Success Criteria

Nominal Success Criteria

Mission Requirements

Goldeneye Requirements

Ground Station

Requirements

Ground Support Equipment

Requirements

Subsystem Requirements:· Bistatic Radar· Attitude Determination and

Control· Navigation· Flight Computing· Communications· Power· Structure· Thermal Control

System Requirements

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Mission Requirements

Requirement Source Verification Source Document

Test/Analysis Number

M-1 Must meet all NS-5 requirements MS TBD TBD

M-2 Must be able to collect GPS signals O-1, O-2 TBD TBD

M-3 Must be able to transmit data to ground station O-1, O-2 TBD TBD

M-4 Must be able to receive data at ground station O-1, O-2 TBD TBD

M-5 Must be able to process data on the ground O-3 TBD TBD

M-6 Must be able to design, fabricate and test Goldeneye on the ground

MS TBD TBD

Three systems to accomplish the mission:

Collects and Transmits

Data

Goldeneye

Receives Goldeneye’s

Data

Ground Station

Processes Goldeneye’s Data

Ground SupportMission

Accomplished!

Scott Franke

Mission Statement(s) if plural will be numbered as shown. Otherwise source will be "MS".

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System 1 Overview: GoldeneyeThe purpose of Goldeneye is to validate a GPS bistatic radar forremote sensing applications onboard small satellites in low Earthorbit.

Attitude Determination and Control: Orients Goldeneye to collect experimental data

– Determines Goldeneye’s attitude– Detumbles and Despins Goldeneye– Points GPS high gain antenna towards Earth using magnetic torquers with +/- 20 accuracy – Assists magnetic torquers by providing gravity gradient stabilization through Goldeneye’s moments of

intertia Data Collection, Storage, and Compression:

Acquires experimental data – Collects raw, Earth-reflected GPS signals for 36 seconds– Collects processed data from direct GPS signals for 36 seconds– Compresses GPS data– Stores GPS data

Transmitting to Ground Station: Allows validation of experimental data

– Listens for transmission window and sends stored GPS data to ground station– Validation of the GPS bistatic radar is achieved through processing the GPS data with our own

algorithms and correlating the processed data with actual ocean surface conditions

RISK

Scott Franke

Each System shall be a monolithic "structure" that operates relatively independent.i.e. a spacecraft, another spacecraft; a ground station, ground operations, rapid integration and test; etc.

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System 1 Requirements: Goldeneye



GS-1 Must be able to operate in Earth orbit M-1 TBD TBD

GS-2 Must have onboard power supply M-1 TBD TBD

GS-3 Must start-up autonomously after deployment M-1 TBD TBD

GS-4 Must be able to determine attitude O-1 TBD TBD

GS-5 Must be able to control attitude O-1 TBD TBD

GS-6 Must be able to determine position and velocity O-2 TBD TBD

GS-7 Must be able to collect, store, and compress data

O-3 TBD TBD

GS-8 Must be able to receive transmissions from the ground station

O-3 TBD TBD

GS-9 Must be able to transmit data to ground station O-3 TBD TBD

Stephen Forbes

Numbering and order of requirements should follow the Requirements and Requirement Verification Document (Document #2 in the FCR documentation guide)

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System 1 Design Overview: GoldeneyeGoldeneye has 8 subsystems for supporting the bistatic radar mission:

Bistatic Radar System (BRS)– direct signal GPS antenna, high gain left-hand polarized GPS antenna, GPS receiver and GPS RF

front end collectorAttitude Determination and Control System (ADCS)

– magnetometer, rate gyro, active magnetic controlNavigation System (NAV)

– direct signal GPS antenna and GPS receiverFlight Computing System ( (FCS)

– embedded computer, data compression and storageCommunications System (COMM)

– amateur packet radio system with built-in TNCPower System (PWR)

– body-mounted solar cells, inhibits, UNP-recommended NiCd battery design, DC-DC conversion, mission mode control

Structure System (STR)– aluminum isogrid panels, solid aluminum component boxes, electrically conductive coatings,

vent holesThermal Control System (THRM)

– Heaters, heat sinks

RISK

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Requirements: Bistatic Radar System (BRS)



BRS-1 Must accept incoming GPS signals M-2 TBD TBD

BRS-1.1 Requires one GN3S Sampler from SiGe. BRS-1 TBD TBD

BRS-1.2 Requires one nadir aligned high gain LHCP antenna capable of receiving signals at 1575MHz (L1 signal).

BRS-1 TBD TBD

BRS-1.3 Requires GN3S software for reflected signal collection. BRS-1 TBD TBD

BRS-1.4 Requires one Novatel OEMV-3G GPS receiver. BRS-1 TBD TBD

BRS-1.5 Requires one RHCP antenna with boresight aligned to GPS satellites capable of receiving signals at 1575MHz (L1 signal).

BRS-1 TBD TBD

BRS-2 Must determine Earth surface conditions NSC-1 TBD TBD

BRS-2.1 Requires communication with flight computer. BRS-2 TBD TBD

BRS-2.2 Requires software GPS receiver (“Q”). BRS-2 TBD TBD

BRS-2.3 Requires MatLab software to process “Q” output. BRS-2 TBD TBD

BRS-3 Must validate experimental results. NSC-1 TBD TBD

BRS-3.1 Requires NOAA National Data Buoy Center data for dates and times of reflected GPS signal data.

BRS-3 TBD TBD

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Design: Bistatic Radar System (BRS)

Antenna ConfigurationGPS Direct Signal Antenna· Collects direct

GPS signals from GPS satellites

GPS High Gain Antenna· Nadir Pointing· Collects Earth-

reflected GPS signals

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Design: Bistatic Radar System (BRS)

Novatel OEMV-3GGPS Receiver

SiGe SE4110LGN3S Sampler

High Gain Reflected GPS Signal Antenna: Nadir Pointing

Direct GPS Signal Antenna

MC

XM

MC

X

RS-232 or USB

USB

Onboard Flash Storage

HW

HW

HW

HW

HW

US

B

Flight Computer

Data Compression Routine

HW

SW

San Jose Navigation, SA-60C Passive GPS

Antenna

TBD: Windows XPePC/104 Footprint

Model TBD

TBD: USB Hub w/ multiple 2 gig USB

Flash drivesTBD

Processed GPS Signal

Raw Reflected GPS Signal

PWR4.5 to 18 V, Expect 5V

5V

TBD, SelfRegulated

2.7V to 3.3V, Self Regulated

If ActiveAntenna

RISK

HW - HardwareSW - Software

- Data Flow

- Power

Legend

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Data: Bistatic Radar System (BRS)

Mission Objective #3: Must be able to transmit data to ground station

BRS Data:• 36 seconds of data is 640 Mb (minimum success criteria)• 134.4 Mb after compression• 234 Minutes required to transmit 36 seconds of data to ground

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Requirements: Attitude Determination and Control System (ADCS)



ADCS-1 Must provide on-orbit Goldeneye attitude data GS-4, GS-5 TBD TBD

ADCS-1.1 Must utilize a rate gyro ADCS-1 TBD TBD

ADCS-1.2 Must utilize a three-axis magnetometer ADCS-1 TBD TBD

ADCS-2 Must detumble Goldeneye on orbit GS-4,GS-5, GS-7

TBD TBD

ADCS-3 Must despin Goldeneye about z-axis GS-4,GS-5, GS-7

TBD TBD

ADCS-4 Must provide on-orbit directional control with a nadir-facing pointing accuracy of +/- 20 degrees

GS-4, GS-5, GS-7

TBD TBD

ADCS-4.1 Must provide passive directional control with gravity gradient stabilization

ADCS-4 TBD TBD

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Design: Attitude Determination and Control System (ADCS)

Objective: Maneuver from a measured attitude to a desired attitude that will allow Goldeneye to perform the bistatic radar experiment.

Attitude Control Algorithms

Actuation: Magnetic Torquers

Goldeneye Attitude

Attitude Sensors: Rate Gyro and Magnetometer

Attitude Determination

Algorithms

Computed Attitude

Desired Attitude

Attitude Control System

Attitude Determination System

RISK

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Design: Attitude Determination and Control System (ADCS)Attitude Determination: • Blend of magnetometer triad and rate gyro

measurementsAttitude Control: • Active control through magnetic torquers• Passive control through gravity gradient stabilization

(no boom)Control Tasks:• Detumble Goldeneye• Despin Goldeneye• Keep high gain antenna pointed towards Earth with +/-

20 degrees accuracyDynamic Stability:• Moment of inertia analysis for gravity gradient

stabilization• Minimizes control authority required by magnetic

torquers

Always pointed towards Earth

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Attitude Determination• Legacy design from Nanosat-4• Attitude determination algorithm has already been validated

– Algorithm validated by using post processed space flight sensor data from the NASA/Stanford Gravity Probe B mission.

– Subject of the following journal manuscript in preparation:• V. L. Bageshwar, D. Gebre-Egziabher, W. L. Garrard, P. Shestople, and M.

Adams, “Inertially Aided Vector Matching Algorithm for Satellite Attitude Determination"

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Attitude Control• Algorithms for detumbling• Algorithms for despinning • Algorithms for nadir pointing• Moments of inertia for gravity

gradient stabilization:– I_roll > I_yaw , Therefore I_xx > I_yy > I_zz

Inside Goldeneye (Bottom Surface)

5 Boxes

Goldeneye

Lightband

Z

X

YY

X

Curtis, Howard D. Orbital Mechanics for Engineers. Elsevier. 2005. Massachusetts. Page 539.

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• Magnetometer: Goodrich FM02 – Measures magnetic field vector of

Earth– 43 grams– 0.33 Watts– Acquired

• Rate Gyro: Honeywell HG1700– Measures angular velocities about

x, y, and z axes– 726 grams– 5.5 Watts– 2 deg/hr drift– Acquired

• Magnetic Torquers: TBD

www.goodrich.com

www.honeywell.com

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Requirements: Navigation System (NAV)



NAV-1 Must determine position and velocity in orbit. GS-6 TBD TBD

NAV-1.1 Requires Novatel OEMV-3G GPS receiver. NAV-1 TBD TBD

NAV-1.2 Requires RHCP antenna capable of receiving signals at 1575MHz (L1 signal).

NAV-1 TBD TBD

NAV-1.3 Requires transmission to FCS for logging of x, y, z (position) and x-dot, y-dot, z-dot (velocity) on orbit.

NAV-1 TBD TBD

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Antenna:• San Jose Navigation SA-60C• 0.06 Watts• Located on top outer surface of

GoldeneyeReceiver:• Novatel OEMV-3G• 2 Watts• Housed in a component box

RISKDesign: Navigation System (NAV)

Using GPS to determine position

and velocity

www.sanav.com

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Design: Navigation System (NAV)

Novatel OEMV-3GGPS Receiver

Direct GPS Signal Antenna

MM

CX

RS-232 or USB

Onboard Flash Storage

HW

HW

HW

US

B

Flight Computer

Data Compression Routine

HW

SW

San Jose Navigation, SA-60C Passive GPS

Antenna

TBD: Windows XPePC/104 Footprint

Model TBD

TBD: USB Hub w/ multiple 2 gig USB

Flash drives

Processed GPS Signal

PWR4.5 to 18 V, Expect 5V

5V

TBD, SelfRegulated

X, Y, ZX-dot, Y-dot, Z-dot

HW - HardwareSW - Software

- Data Flow

- Power

Legend

Legacy design from Nanosat-4

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Requirements: Flight Computing System (FCS)



FCS-1 Must collect all sensor data GS-7 TBD TBD

FCS-2 Must compress data for storage GS-7 TBD TBD

FCS-3 Must store collected data onboard GS-7 TBD TBD

FCS-4 Must determine attitude GS-4 TBD TBD

FCS-5 Must control attitude GS-5 TBD TBD

FCS-6 Must decide when to turn on bistatic radar experiment

GS-7 TBD TBD

FCS-7 Must be able to communicate with Communication System

GS-9 TBD TBD

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Design: Flight Computing System (FCS)

Hardware/Software:• Arcom PC-104 embedded

computer– 1.6 Watts– 95 grams– 400 MHz processor– 5 serial ports, RS232– 2 USB ports– Programming language: C– Acquired with Linux, looking for

another that supports Windows for the GPS RF front end Interface Software

• Flash memory – 2 Gb required

• Software data management and test plan

– Account for all I/O– Account for all processes associated

with the I/O– Computing Budget

RISK

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Design: Flight Computing System (FCS)Heaters

Temp Sensors

Current Sensors

Power Switches

Voltage Sensors

Flight Computing

System

RS232 COM4

Navigation and ADCS

RS232 COM2

Power Manager

Magnetometer

Rate Gyro

GPS Reciever

Torque Coils

Bi-static Radar

System

Primary Radio

Data Storage Device

Backup Radio

USB 1.1

USB 1.1 RS232 COM1

RS232 COM3

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Requirements: Communication System (COMM)



COMM-1 Must abide by applicable FCC regulations M-1 TBD TBD

COMM-2 Must have inhibits preventing RF emissions before deployment

M-1 TBD TBD

COMM-3 Must be able to communicate with Ground Station during transmission windows

GS-8, GS-9

TBD TBD

COMM-4 Must be able to communicate with Flight Computing System

GS-9 TBD TBD

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Design: Communications System (COMM)2 Radios: Kenwood TH-D7A• Nanosat-4 Legacy• 380g• 54.0 x 119.5 x 43.5 mm• 1.65 Watts (receiving)• 26 Watts (transmitting)Transceiver Functional Characteristics:• Modulation: Reactance• Transmitting power: 5 Watts• Frequency deviation +/- 5kHzModem Functional Characteristics:• 9.6 kb/s• 440 MHz (transmitting)/144 MHz (receiving)• Protocols: AX.252 Antennas:• Omnidirectional, nondeployable, on top of Goldeneye• Current height of transmitting antenna causes approx. 14

cm breach of static envelope-considering other options

RISK

Radio

DC PowerFlight

Computing System

Antenna

Goldeneye

Lightband

Whip Antenna13.4 inches long, for

transmitting, 440 MHzWhip Antenna, for receiving.

144 MHz

Shown for one radio.Second radio is the same.

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Requirements: Power System (PWR)Requirement Source Verification

Source Document


PWR-1 Must have inhibits to prevent start-up before deployment GS-3 TBD TBD

PWR-2 Must charge batteries with solar cells GS-2 TBD TBD

PWR-3 Must control component activation and deactivation GS-3 TBD TBD

PWR-4 Must supply power to components at regulated voltages GS-1 TBD TBD

PWR-5 Must supply enough power to support mission MS TBD TBD

PWR-6 Must protect components from transients GS-1 TBD TBD

PWR-7 Must protect components from overcurrent GS-1 TBD TBD

PWR-8 Must prevent batteries from overcharging GS-1 TBD TBD

PWR-9 Must mitigate short circuit failures GS-1 TBD TBD

PWR-10 Must monitor health GS-1 TBD TBD

PWR-10.1 Must monitor bus voltages GS-1 TBD TBD

PWR-10.2 Must monitor bus currents GS-1 TBD TBD

PWR-10.3 Must monitor component currents GS-1 TBD TBD

PWR-10.4 Must monitor component logic states GS-1 TBD TBD

PWR-10.5 Must monitor battery voltage GS-1 TBD TBD

PWR-10.6 Must receive component box temperature data from thermal control system GS-1 TBD TBD

PWR-11 Must transmit health data to flight computer GS-7 TBD TBD

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Design: Power System (PWR)

Solar Cells: • EMCORE 607094, 192 cells• 28% efficient• Triple junction GaAs • Average power at least 35 WattsBatteries: • 14 Sanyo N-4000DRL cells• Provided by AFRL

DC/DC Power Supply: • American power design D150-15/5,

88% efficient, • dual regulated outputs: 5V and 15VPower Manager: • PIC controller• Monitors health of batteries and

hardware• Activates/Deactivates components

based on health data

Solar Cells BatteriesDC/DC Power Supply

Power Manager

Satellite Components

RISK

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Solar Panel 1

Solar Panel 6

Solar Panel 5

Solar Panel 4

Solar Panel 3

Solar Panel 2

Batteries

DC/DC Power Supply5 V 15 V

15V

-Loa

ds

5V-L

oads

Sun

Power Sources:· Eclipse: Batteries· Sun: Solar Cells and

Batteries

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Components and Circuitry• Heaters• Inhibits• Power Switches• Voltage Monitors• Current Monitors• Temperature Monitors• Load Status Monitors• Transient Protection• Overvoltage Protection• Overcurrent Protection• Short Circuit Protection

Telemetry• Battery Voltage• Bus Voltage• Bus Current• Component Current• Load Status• Battery Box Temperature

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Design: Power System (PWR) > Power Budget

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Requirements: Structure (STR)



STR-1 to STR-23

Must comply with Nanosat-5 program requirements

M-1 TBD TBD

STR-24 Must provide metal components boxes for Goldeneye's hardware

GS-1 TBD TBD

STR-25 Must have an electrically conductive coating on metal component boxes

GS-1 TBD TBD

STR-26 Must have moments of inertia such that I_xx > I_yy > I_zz

ADCS-4.1 TBD TBD

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Requirements 1 – 23: Structure (STR)

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Design: Structure (STR)

Aluminum 6061-T6 Panels:• Circular isogrid design• Electrically conductive coating

RISK

Lightband Interface

Solar Panels

GPS Direct Signal

Antenna

GPS High Gain

Antenna

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Design: Structure (STR)

Aluminum 6060-T6Component Boxes:• Housing for hardware• 2-piece design• Electrically conductive

coating• 2 vent holes, 0.25” diameter,

size based on results of venting analysis

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S1.7 Design: Structure

Structural AnalysisObjective: Gain familiarity with ANSYS• Model 1: Confirmation of ANSYS stress

deformation results by hand calculation of compressive axial loading of simple rectangular beam.

• Model 2: Confirmation of ANSYS stress results by hand calculation of a supported plate under acceleration load.

Further Analysis:• Brackets, component boxes, isogrid

panels, solar panels, buckling analysis

Model 1: Stress at Fixed BaseHand Calculation: s = 706 kPaANSYS solution: s = 723 kPa

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Requirements: Thermal Control System (THRM)



THRM-1 Must maintain proper temperature ranges for components to operate

GS-1 TBD TBD

THRM-1.1 Must monitor temperature within every component box

THRM-1 TBD TBD

THRM-1.2 Must transmit temperature data to power manager

THRM-1 TBD TBD

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Design: Thermal Control System (THRM)

• Heat sinks for components with 1 Watt power consumption• Heaters for temperature sensitive components• Operating Temperatures:

RISK

Viper PC-104 computer -20 to 70 degrees Celsius

Novatel GPS receiver -40 to 85 degrees Celsius

Kenwood TH-D7A radios -20 to 60 degrees Celsius

GPS direct signal antenna -40 to 85 degrees Celsius

Sanyo N-4000DRL batteries 0 to 40 degrees Celsius

Honeywell HG1700 rate gyro TBD

Goodrich FM02 magnetometer -55 to 88 degrees Celsius

APD D150-15/5 power supply -25 to 85 degrees Celsius

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• Temperature Sensors– Minco S3238PAZT36TB– 12.7 X 31.8 X 1.3 mm

• Heaters– Minco HK5160R157L12B– 12.7 X 50.8 X 1.3 mm

www.minco.com

Hardware:

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Thermal Analysis• Transient model, 27 orbital scenarios, 1 node, sphere with same surface

area as Goldeneye

• Worst Case Hot:– Goldeneye Surface: 75.0 degrees C (67.5 degrees avg)– Goldeneye Payload: 75.3 degrees C (71.3 degrees avg)– Altitude: 150 km

• Worst Case Cold:– Goldeneye Surface: -11.0 degrees C (-7.5 degrees avg)– Goldeneye Payload: -9.2 degrees C (-7.3 degrees avg)– Altitude: 450 km

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System 2 Overview: Ground Station

• Communicate, track, and receive data from Goldeneye• Send messages to Goldeneye• Used with amateur packet radio• Located at University of Minnesota

RISK

46

System 2 Requirements: Ground Station (GND)



GND-1 Must abide by applicable FCC regulations M-1 TBD TBD

GND-2 Must have no less than 90 degrees range in elevation

M-3 TBD TBD

GND-3 Must have no less than 360 degrees range in azimuth

M-3 TBD TBD

GND-4 Must be able to track Goldeneye in any orbit M-3 TBD TBD

GND-5 Must have antenna gain large enough to close link with Goldeneye

M-3 TBD TBD

GND-6 Must be able to transmit data to Goldeneye GS-8 TBD TBD

GND-7 Must be able to receive data from Goldeneye GS-8 TBD TBD

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Design Overview: Ground Station (GND)

DC Power Supply:– TBD

Transceiver:– TBD– Receives signal from Goldeneye– Transmits signal from PC

TNC (Terminal Node Controller):– Kantronics KPC3+– Takes signal from radio and

converts to digital signal– Sends digital signal to computer

PC:– Dell Latitude C640 #PP01L– Collects and stores data– Controls TNC– Controls rotator– Tracks Goldeneye (NOVA

software)2 Antennas:

– M2 inc: 2MCP22 (144 MHz) Transmits to Goldeneye

– M2 inc: 436CP42UG (440 MHz) Receives from Goldeneye

RISK

Transceiver TNC

DC Power Supply

PC

Antenna

48

Design Overview: Ground Station (GND)

Rotator• Yaesu G5500 with GS-232A Computer interface• Azimuth Range 0 to 360 Degrees• Elevation Range 0 to 90 Degrees• Max Rotation Speed 6 deg/sec (azimuth), 2.5 deg/sec (elevation)• Rotates the antennas to follow Goldeneye

Rotator

436CP42UG(440 MHz, Receives)

2MCP22(144 MHz, Transmits)

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Communication – Link & Licensing

RF Link– Signal to noise ratio: -3 dbm– Bit error rate: TBD, based on design and outside interference– Modulation type vs. channel distortion: TBD

Licensing– At least level 1 technician – Frequencies: 144/440 MHz (HAM)– Status: Waiting to hear back from FCC about Call sign for Goldeneye, and

frequency allocation.

RISK

50

System 3 Overview : Ground Support Equipment (GSE)

• Transportation– Lifting mechanism– Long distance travel container

• Allow complete operation of Goldeneye pre-launch– Autonomous and remotely controlled mission simulations– Charge, discharge, equalize batteries

• Monitor Goldeneye on the ground– Pre-launch data collection through flight computer interface, electrical interface, or

radios – Post-launch data collection through radios

• Process Goldeneye’s data on the ground– Data management plan– Computer designated for processing data

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Requirements: Ground Support Equipment (GSE)



GSE-1 Must have mechanical ground support equipment (MGSE) M-8 TBD TBD

GSE-1.1 Must have a lifting mechanism to lift Goldeneye from a single point above its center of gravity

M-1 TBD TBD

GSE-1.2 Must have a safety factor of 5 M-1 TBD TBD

GSE-1.3 Lifting mechanism must not contact Goldeneye or nanosat separation system

M-1 TBD TBD

GSE-2 Must have electrical ground support equipment (EGSE) M-8 TBD TBD

GSE-2.1 Must monitor inhibits status M-1 TBD TBD

GSE-2.2 Must comply with KHB 1700.7C M-1 TBD TBD

GSE-2.3 Must monitor voltage of all battery cells M-1 TBD TBD

GSE-2.4 Must use-scoop-proof connectors M-1 TBD TBD

GSE-2.5 Must utilize fuse and diode protection to prevent EGSE and usage failures from affecting Goldeneye's hardware

M-1 TBD TBD

GSE-2.6 Must collect data from all of Goldeneye’s subsystems M-1 TBD TBD

52

Design Overview : Ground Support Equipment (GSE)

Electrical Ground Support Equipment

Battery Maintenance:• Allows Nanosat team to charge, discharge, equalize batteries etc.Remote Activation:• “Master Switch” overrides Goldeneye’s onboard subsystems• Allows Nanosat team to activate or deactivate GoldeneyeFlight Computer Interface:• Provides subsystem data to laptop• Allows Nanosat team to send commands/instructions to Goldeneye Electrical Interface:• Provides data to laptop for battery cell voltages and inhibits status

GoldeneyeFrom Goldeneye:· Battery cell voltages· Inhibits status· Subsystem data

From Laptop:· Commands/ Instructions

Ports on Goldeneye:· Battery Maintenance· Remote Activation· Flight Computer

Interface· Electrical Interface

RISK

53

Lightband Interface

Wires from Goldeneye connect inhibits to

microswitches

Launch Vehicle Interface

• Mechanical interface– Aluminum ring protruding from

Goldeneye’s bottom structural panel provides integration with Lightband system

• Electrical interface– 2 microswitches in Lightband

will actuate Goldeneye’s inhibits– Wire pigtails from Goldeneye will

hang 12” below SIP to connect to microswitches

RISK

54

= low risk = medium risk = high risk NA = N/ABRS

ADCS

NAV

FCS

COM

M

PWR

THRM

STR

GND

GSE

Overall Program

Assessm

ent

Performance

Schedule

Cost

Safety

Testing

Manpower

Facilities

Overall Subsystem Assessment NA

Program/Subsystem Risk Assessment

Familiar with design, hardware and implementation

Somewhat familiar with design, hardware and implementation

Not familiar with design, hardware and implementation

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Relevance of GPS Bistatic Radar

• Easy implementation:Easy implementation: requires compact, low power existing hardware that many satellites already use.

• Reliable:Reliable: Augments other data collection systems that can be affected by weather.

• Inexpensive:Inexpensive: Collects the same data as vital satellites such as QuikSCAT, but at a lower cost.

56

Summer 2007 Organization

Demoz Gebre-Egziabher – PI

•[email protected]

Ellie Field – Student PM

•[email protected]

Ellie FieldStudent PM

Katrina FaucettCOMM and GND

Lead

Mike BrownFCS Lead

Jim PogemillerBRS Lead

(MS: Aerospace Engineering)

Mike LegattSTR Lead

Trevor BainProgrammer

Brett BurgstahlerADCS Lead

Demoz Gebre-EgziabherPI

(Faculty: Aerospace Engineering)

Jonah White

STR Team

57

K-12 Outreach

• Farnsworth Elementary June 1, 2007• Exhibit at the Minnesota State Fair, September 1, 2007• Tennant Take Your Child to Work Day June 2008

Students from Farnsworth Elementary visiting the Nanosat lab at the University of Minnesota

58

Spacecraft Overview: Exploded View

Radios

Batteries

GPS Direct Signal Antenna

Flight Computer

Solar Panel

59

Solar Cell Mounting: How

Materials:• Solar cells: Emcore triple junction GaAs• Primer: Nusil CF6-135• Adhesive: Nusil CV10-2568• Kapton: 3M 1205 Acrylic Tape• Aluminum Honeycomb Panel: Plascore,

0.05”-thick facesheets, 0.5”-thick perforated core

Process Overview:• Adhere kapton to cleaned aluminum

honeycomb panel• Deaerate adhesive and apply with

primer to cleaned kapton using a stencil

• Apply primer to the back of cleaned solar cell strings

• Remove stencil and place solar cells strings on adhesive

Solar Cells

PrimerAdhesive

Kapton

Aluminum Honeycomb Panel

Primer

60

Solar Cell Mounting: Where

192 Solar Cells Total• Top panel: 60 cells• Bottom panel: 12 cells• Side panel: 30 cells each

Bottom Panel

Top Panel

Side Panel: 4 Total

61

Power System: Inhibit Schematic

Inhibits:• Total of 8 independent latching relays, board mounted in

different orientations• Prevent batteries from charging• Prevent solar power from reaching power supply• Prevent battery power from reaching power supply

Solar Cells BatteriesDC/DC Power Supply

Satellite Components

INH

INH x 3 INH x 3

INH

62

Electrical Systems and Power: Battery Box Design

• Batteries– 14 Sanyo NiCd Type N-4000DRL cells, strung in series with

spot welded Ni201 tabs – 16.8 V, 4 A-hr Battery– Kapton or Kynar insulation for Ni201 tabs– Fuse included in battery box

• Battery box– 6061-T651 aluminum cell holder, anodized– 6061-T651 Al, Alodine exterior coating, anodized interior

coating– Cells fastened to cell holder using Eccobond 285, provides

thermal path– MAT301 absorbent material installed in void spaces to

minimize free volume.– Two filtered vents– Two thermistors for temperature sensing– Two heaters for maintaining operating temperature

• Battery Testing– Cell level acceptance testing– System level thermal testing followed by battery servicing– Temperature, capacity and voltage monitoring during

thermal testing• Alodine: Mil-C-5541E Class 3• Anodization: Mil-A-8625 “F” Type II Class 2

Lid

Lid Gasket

Batteries

Cell Holder

Battery Box

Mesh

Gasket

Vent Hole Cover

Vent Hole

63

COMM: Link budget

64

Detailed Schedule

65

Integration and Testing:

BRS Assembly

COMM Assembly

ADCS Assembly

NAV Assembly

FCS Assembly

PWR Assembly

STR Assembly

GND Assembly

GSE Assembly

BRS Functional Test

COMM Functional Test

ADCS Functional Test

NAV Functional Test

FCS Functional Test

PWR Functional Test

STR Functional Test

GND Functional Test

GSE Functional Test

System Integration

System Tests:· Bakeout· Thermal Vacuum· Pressure Profile· Envelope Verification· Mass Properties· EMC Self-Compatibility· Electrical System Aliveness

and Functional Tests

Before J uly 2008: Before October 2008:

Before J an. 2009

All tests performed at the University of Minnesota, before FCR

66

Structural TestsTest Component Spacecraft Margins

Strength•Sine Burst, Yield, Ultimate

X Sine burst at 1.2 times yield requirement, yield SF=2, ultimate SF=2.6

Random Vibration/ Acoustic X 0.25 gRMS from 20 to 2000 Hz (more, table 8.2)

Shock X 100-10000 Hz, ASD levels see table 8.3

Stiffness•Sine Sweep

X Natural frequency 100 Hz, 0.25 gRMS from 20 to 2000 Hz

Thermal TestsBakeout X X

Thermal Vacuum X X

Physical TestsPressure Profile X X Depressurization 0.5psi/sec, Repressurization 0.3psi/sec,

SF=2

Envelope Verification X 60 cm width, 50 cm height

Mass Properties X X 50 kg

EMC TestsSelf-Compatibility X X MIL-STD-461E

Functional TestsElectrical System Aliveness and Functional Tests X X

Integration and Testing (table 8-1)

67

Bistatic Radar System Detailed Requirements

Subsystem / Component Requirements MethodMust accept incoming GPS signals

Antenna must be LHCP to avoid a 3dB signal loss due to reflected polarization at the L1 signal frequency (1575.42MHz).

Design, Test

SiGe GPS Front End must accept data using the GN3S software. Design, Test

Must determine Earth surface conditionsMust plot GPS signal characteristics as a delay vs. Doppler map Analysis

Signal characteristics used to correlate to NOAA ocean buoy data and QuikScat satellite data

Analysis

Must validate experimental results.Use uncorrelated Goldeneye data to predict ocean surface conditions then compare those conditions to NOAA buoy data and QuikScat satellite data.

Analysis

68

ADCS Detailed Requirements

Subsystem / Component Requirements MethodMust provide on-orbit Goldeneye attitude dataWill utilize a magnetometer and a rate gyro to determine attitude. Design, Test

Must provide data to the flight computer. Design, Test

Must detumble and despin Goldeneye on orbitWill utilize magnetic torquers. Analysis

Must provide on-orbit directional control with a nadir-facing pointing accuracy of +/- 20 degreesWill utilize magnetic torquers. Analysis

Will use gravity gradient stabilization to augment magnetic torquers. Analysis

69

Navigation System Detailed Requirements

Subsystem / Component Requirements MethodMust determine position and velocity in orbit.Will utilize OEMV-G3 GPS receiver for navigation solution. Design, Test

Will use San Jose SA-60C GPS antenna. Design, Test

Must provide navigation solution to the flight computer. Test

70

FCS Detailed Requirements

Subsystem / Component Requirements Method

Must collect all sensor data.Must accept incoming sensor data from all sources. Design, Test

Must compress data for storageWill use data compression algorithm similar to WinZip. Test

Must store collected data onboard.Will utilize at least 2 Gb flash memory. Analysis

Must determine attitude.Must have algorithms to determine attitude. Test

Must Control Attitude.Must have algorithms to control attitude for desipinning, detumbling, and nadir pointing.

Analysis, Test

Must decide when to turn on bistatic radar experiment.Will compare navigation solution to a matrix of predetermined global locations of ocean boundaries.

Analysis

Must be able to communicate with Communication System.Requires an RS232 connection to the radios. Design, Test

71

Communication System Detailed Requirements


Must abide by applicable FCC regulations.Must have personnel with amateur radio licenses. Analysis

Must contact FCC for frequency allocation and call sign. Analysis

Must have inhibits preventing RF emissions before deployment.Will be inhibited by four independent latching relays that are a part of the power system’s inhibits.

Design, Test

Must be able to communicate with Ground Station during transmission windows.Must have an antenna that receives at 144 MHz and transmits at 440 MHz Analysis, Test

Must be able to communicate with Flight Computing System.Must have RS232 interface between radios and flight computer. Test

72

Power System Detailed RequirementsSubsystem / Component Requirements MethodMust have inhibits to prevent start-up before deployment.

Must have eight independent inhibits in the configuration specified by the User’s Guide. Design, Test

Must charge batteries with solar cells.

Must connect solar cells to batteries and allow electrical power to bypass batteries when batteries are full. Design, Test

Must control component activation and deactivation.

Must control power switches to each component. Design, Test

Must supply power to components at regulated voltages.

Will use a DC/DC converter with dual outputs at regulated voltages. Design, Test

Must supply enough power to support mission.

Must have enough solar cells and battery capacity to support mission. Analysis, Test

Must protect components from transients.

Will utilize filters and decoupling capacitors. Design, Test

Must protect components from overcurrent.

Must monitor current consumption of each component. Design, Test

Must deactivate component if current draw is beyond component threshold. Design, Test

Must prevent batteries from overcharging.

Must divert solar power to DC/DC converter when batteries are full Design, Test

Must mitigate short circuit failures.

Must utilize a single point ground. Design, Test

Must monitor health.

Must collect data from sensors that monitor battery voltages, bus voltages, component current, bus current, component logic states and component box temperatures.

Design, Test

Must transmit health data to flight computer.

Must communicate with flight computer through an RS232 link. Design, Test

73

Structure Detailed Requirements

Subsystem / Component Requirements MethodMust comply with Nanosat-5 program requirements.See requirements verification matrix. Design, Analysis, Test

Must provide metal components boxes for Goldeneye's hardware.Will use fully enclosed aluminum boxes Design, Analysis

Will have vent holes Analysis

Must have an electrically conductive coating on metal component boxes.Will use Alodine Analysis

Must have moments of inertia such that I_xx > I_yy > I_zz.Must enable gravity gradient stabilization in orbit Design, Analysis

74

Thermal Control System Detailed Requirements

Subsystem / Component Requirements MethodMust maintain proper temperature ranges for components to operate.Must monitor temperature within every component box. Design, Test

Will use heat sinks for components that consume greater than 1 Watt. Design, Analysis, Test

Will use heaters. Design, Analysis, Test

75

Ground Station Detailed Requirements


Must abide by applicable FCC regulations.Must have personnel with amateur radio licenses. Analysis

Must contact FCC for frequency allocation and call sign. Analysis

Must have no less than 90 degrees range in elevation.Will use Yaesu G5500 rotator. Design, Analysis, Test

Must have no less than 360 degrees range in azimuth.Will use Yaesu G5500 rotator. Analysis

Must be able to track Goldeneye in any orbit.Will utilize NOVA software. Analysis

Must have antenna gain large enough to close link with Goldeneye.TBD Analysis

Must be able to transmit data to Goldeneye.Will use antenna from M2 inc: 2MCP22 (144 MHz). Analysis, Test

Must be able to receive data from Goldeneye.Will use antenna from M2 inc: 436CP42UG (440 MHz). Analysis, Test

76

GSE Detailed Requirements

Subsystem / Component Requirements MethodMust have mechanical ground support equipment (MGSE).Must have a lifting mechanism to lift Goldeneye from a single point above its center of gravity.

Design, Test

Must have a safety factor of 5. Analysis

Lifting mechanism must not contact Goldeneye or nanosat separation system. Design, Analysis

Must have electrical ground support equipment (EGSE).Must monitor inhibits status. Design, Test

Must comply with KHB 1700.7C. Analysis, Test

Must monitor voltage of all battery cells. Design, Test

Must use-scoop-proof connectors. Design

Must utilize fuse and diode protection to prevent EGSE and usage failures from affecting Goldeneye's hardware.

Analysis, Test

Must collect data from all of Goldeneye’s subsystems. Design, Test

Mission Overview

Documents

Transcript of Mission Overview