ERV 4ERV 4Fall 2003Fall 2003

Sean M. BarracloughSean M. BarracloughBenjamin R. EastmondBenjamin R. Eastmond

Jessica E. GattoJessica E. GattoMatthew F. KauffmannMatthew F. Kauffmann

Joel D. RichterJoel D. RichterAmber M. WilsonAmber M. Wilson

The Pennsylvania State University

Aerospace 401

ERV ConfigurationERV Configuration

Mission ArchitectureMission Architecture

StructuresStructures

Cylindrical DesignCylindrical DesignMonolythicMonolythicDampening Dampening Docking Adaptor Docking Adaptor Large Space UsesLarge Space Uses

Food StorageFood StorageComputer and Communications EquipmentComputer and Communications EquipmentEntertainmentEntertainment

StructuresStructures

Friction Stir WeldingFriction Stir Welding

Aluminum Metal Matrix CompositesAluminum Metal Matrix Composites

Magnum Launch VehicleMagnum Launch Vehicle85,000kg 85,000kg 2 launches2 launches

PropulsionPropulsion

Liquid bipropellant system using CHLiquid bipropellant system using CH44 as fuel and as fuel and

OO2 2 as oxidizeras oxidizer

RD-0234-CH = main engine located on landerRD-0234-CH = main engine located on lander

T = 442 kN; IT = 442 kN; Ispsp = 343 sec; m = 390 kg = 343 sec; m = 390 kg

RD-183 = smaller engines used as thrustersRD-183 = smaller engines used as thrusters

T = 9.80 kN; IT = 9.80 kN; Ispsp = 360 sec; m = 60 kg = 360 sec; m = 60 kg

Ground ControlGround Control

Dedicated Ground SystemDedicated Ground System Co-located MCC, POCC, SOCCCo-located MCC, POCC, SOCC Combinations POCC and SOCCCombinations POCC and SOCC

Back-up Ground StationBack-up Ground Station

Manned by minimum number of staffManned by minimum number of staff

CommunicationsCommunications

Deep Space NetworkDeep Space Network High Gain Antennae (HGA)High Gain Antennae (HGA) Two Low Gain Antennae (LGA)Two Low Gain Antennae (LGA) Total Communications SystemTotal Communications System

One HGA, 2 m diameterOne HGA, 2 m diameter Two LGA, 0.25 m diameterTwo LGA, 0.25 m diameter Receiver and transmitter, combined measuring 5 m by 2 Receiver and transmitter, combined measuring 5 m by 2

mm Total weight: 160 kgTotal weight: 160 kg

CommunicationsCommunications Mars Reconnaissance OrbiterMars Reconnaissance Orbiter

Launch 2005Launch 2005 Intermediary link between Intermediary link between

ERV and DSNERV and DSN Guidance system to help ERV Guidance system to help ERV

when entering Mar’s orbitwhen entering Mar’s orbit Beacon SystemBeacon System

Monitor overall health of ERV Monitor overall health of ERV going to Marsgoing to Mars

Sends out one of 4 carrier Sends out one of 4 carrier tones indicating ERV healthtones indicating ERV health

Easily detected, low cost, Easily detected, low cost, frees up space on DSNfrees up space on DSN

OrbiterLander

Mars Recon

Earth/DSN

Communications Relay System (when in Mars orbit)

Beacon System

Command and Data HandlingCommand and Data Handling

Completely redundant, no single point failureCompletely redundant, no single point failure Space Shuttle uses 5 computers, 2 running, 3 as back-upSpace Shuttle uses 5 computers, 2 running, 3 as back-up

Space Shuttle computersSpace Shuttle computers Mass: 29 kgMass: 29 kg 550 W power550 W power

Our system if trends in new technology continueOur system if trends in new technology continue 9 times faster9 times faster 30% less electricity30% less electricity 220W power 220W power 60% less mass60% less mass 7kg per computer 7kg per computer TotalsTotals

70kg mass70kg mass 1375W electricity1375W electricity

Guidance, Navigation Guidance, Navigation and Controland Control

Attitude controlAttitude control

NavigationNavigation CT-63X Star Sensor by Ball Aerospace & CT-63X Star Sensor by Ball Aerospace &

Technologies Corp, model CT-633Technologies Corp, model CT-633

3-AXIS STABILIZEDCASSINI SPACECRAFT

CCD Imaging System

CT-63X

Guidance, Navigation, and Guidance, Navigation, and ControlControl

Inertial Reference Frame DevicesInertial Reference Frame Devices Three gyros that provide attitude reference similar to Three gyros that provide attitude reference similar to

system of space shuttlesystem of space shuttle

Mars Reconnaissance OrbiterMars Reconnaissance Orbiter

Total weight of subsystem: 100kgTotal weight of subsystem: 100kg

Power SubsystemPower Subsystem

Orbiter Orbiter Solar arraySolar array

Lander Lander Nuclear Fission Nuclear Fission

ReactorReactor

Power Requirements (kWe)Power Requirements (kWe)

OrbiterOrbiter LanderLander

StructureStructure   N/AN/A N/AN/A

PropulsionPropulsion      

Power (provided)Power (provided)   (20)(20) (140)(140)

ThermalThermal   

Command and DataCommand and Data 0.780.78 0.520.52

SynthesisSynthesis   N/AN/A 140140

CommunicationCommunication 0.060.06   

Life SupportLife Support      

Scientific InstrumentsScientific Instruments   

Guidance Nav. & ControlGuidance Nav. & Control 0.10.1   

Power Requirements Table

ThermalThermal

ISS Radiator

LanderLander Powered down during interplanetary cruisePowered down during interplanetary cruise Nuclear reactor: large series of pipes Nuclear reactor: large series of pipes to dissipate heat when on Marsto dissipate heat when on Mars Fuel synthesis neutral in heat requirementsFuel synthesis neutral in heat requirements

OrbiterOrbiter Maximum solar radiation when in Earth orbitMaximum solar radiation when in Earth orbit Will generate up to 46kW of rejected heatWill generate up to 46kW of rejected heat Average satellite uses 3.4% of dry mass for thermal subsystemAverage satellite uses 3.4% of dry mass for thermal subsystem

Environmental Control and Life Environmental Control and Life SupportSupport

Oxygen regenerated Oxygen regenerated through electrolysis of through electrolysis of HH22OO

Reusing COReusing CO2 2 molecular molecular

sievessieves Purifying HPurifying H22O through O through

thermoelectric processthermoelectric process Ionization & photoelectric Ionization & photoelectric

flame detectors; COflame detectors; CO2 2

repressantrepressant Dehydrated foodDehydrated food

Crew composed of 2 men Crew composed of 2 men & 2 women& 2 women

Group testing under Group testing under stressful conditionsstressful conditions

Sandy beach theme Sandy beach theme within ERVwithin ERV

Personal locker spacePersonal locker space

Physiological Psychological

Scientific InstrumentsScientific Instruments

Thermometers, Lidar device, accelerometers, Thermometers, Lidar device, accelerometers, altimeters, seismometers, & pressure sensorsaltimeters, seismometers, & pressure sensors

-M = 570 kg-M = 570 kg Multispectral imageryMultispectral imagery

-M = 250 kg-M = 250 kg Robotic Chemical Analysis LaboratoryRobotic Chemical Analysis Laboratory

-M = 2.4 kg-M = 2.4 kg

SynthesisSynthesis

RequirementsRequirements Create 80,000 kg propellant within 780 daysCreate 80,000 kg propellant within 780 days LightweightLightweight Reasonable power drawReasonable power draw

ResultResult S/E-RWGS SystemS/E-RWGS System Mass = 490 kgMass = 490 kg Power requirement = 140 kWPower requirement = 140 kW Hydrogen requirement = 4,570 kgHydrogen requirement = 4,570 kg Mass Savings: 93.675%Mass Savings: 93.675%

Cost AnalysisCost AnalysisEstimated Cost Per ERV Assuming Five ERV's Produced

0

500

1000

1500

2000

2500

0.5 0.6 0.7 0.8 0.9 1

Learning Curve

Est

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ed C

ost

(m

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FY

99 U

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uncrewed

crewed

Future WorkFuture Worka.a. For the structures system we need to finalize exactly what subsystems will be on the orbiter and what subsystems will remain on the lander. This will For the structures system we need to finalize exactly what subsystems will be on the orbiter and what subsystems will remain on the lander. This will

be an important step in determining where the center of mass will be. We also need to obtain the exact amount of propellant needed for station be an important step in determining where the center of mass will be. We also need to obtain the exact amount of propellant needed for station keeping of the orbiter and any other maneuvers that will not be as fuel-expensive. Finally we will have to make final material selections in order to keeping of the orbiter and any other maneuvers that will not be as fuel-expensive. Finally we will have to make final material selections in order to minimize our mass per component. This will be a lengthy process that will require detailed structural analysis of the ERV and its individual minimize our mass per component. This will be a lengthy process that will require detailed structural analysis of the ERV and its individual components.components.

b.b. The packaging of the ERV inside the launch vehicle payload fairing must be analyzed to ensure the space is used as efficiently as possible. In The packaging of the ERV inside the launch vehicle payload fairing must be analyzed to ensure the space is used as efficiently as possible. In addition, the launch location should be decided.addition, the launch location should be decided.

c.c. The propulsion subsystem still needs the exact location on the ERV’s structure for all engines to be found. The main engine was postulated to be The propulsion subsystem still needs the exact location on the ERV’s structure for all engines to be found. The main engine was postulated to be toward the lower end of the spacecraft, however, the other two smaller engines used for thrusters have to be placed in a specific region on the ERV.toward the lower end of the spacecraft, however, the other two smaller engines used for thrusters have to be placed in a specific region on the ERV.

d.d. The feasibility of all the aspects of our ground control system needs to be revisited, along with finding out a total cost estimate for the subsystem. The feasibility of all the aspects of our ground control system needs to be revisited, along with finding out a total cost estimate for the subsystem. Space to ground data rates need to be determined and required data handling established. The communications links need to be selected and the Space to ground data rates need to be determined and required data handling established. The communications links need to be selected and the actual layout of our ground system determinedactual layout of our ground system determined..

e.e. We need to find data rates for the high gain antennae and figure out if our estimated size for the dish will be large enough to handle the data We need to find data rates for the high gain antennae and figure out if our estimated size for the dish will be large enough to handle the data transmitting requirements of the ERV. We also need to find out the cost of all the parts of the subsystem. The placement of the antennas on the transmitting requirements of the ERV. We also need to find out the cost of all the parts of the subsystem. The placement of the antennas on the structure needs to be determined along with the shielding they will need. We need to figure out the actual shielding requirement as well. Lastly we structure needs to be determined along with the shielding they will need. We need to figure out the actual shielding requirement as well. Lastly we need to find and actual transmitter and receiver system to run the antennas. need to find and actual transmitter and receiver system to run the antennas.

f.f. No mass or power requirement information has been found about components of the C&DH subsystem except for the computers. The computers No mass or power requirement information has been found about components of the C&DH subsystem except for the computers. The computers require more mass and much more power than the rest of the subsystem, but other factors, such as cabling will affect the total mass and power require more mass and much more power than the rest of the subsystem, but other factors, such as cabling will affect the total mass and power requirements. Future work will include finding information about other components of the C&DH subsystem to determine more accurately the mass requirements. Future work will include finding information about other components of the C&DH subsystem to determine more accurately the mass and power they require.and power they require.

g.g. For the guidance navigation and control subsystem we need to find out several values. First we need to learn more about the IMU’s, such as exactly For the guidance navigation and control subsystem we need to find out several values. First we need to learn more about the IMU’s, such as exactly how they work, exactly how big they need to be for a spacecraft our size, and how much they will weigh. After all this is determined we need to find how they work, exactly how big they need to be for a spacecraft our size, and how much they will weigh. After all this is determined we need to find out how much power, overall these will consume. Since we were able to find and exact star tracker we wanted to use for our ERV the only part we out how much power, overall these will consume. Since we were able to find and exact star tracker we wanted to use for our ERV the only part we have left there is discovering where it needs to be placed how it needs to work in with all the other subsystems. Lastly we need to learn more about have left there is discovering where it needs to be placed how it needs to work in with all the other subsystems. Lastly we need to learn more about how the thrusters will work to control the attitude and this will affect the overall propulsion of the ERV.how the thrusters will work to control the attitude and this will affect the overall propulsion of the ERV.

h.h. The requirements of the power subsystem are very specific based on what every other subsystem needs. Unfortunately there is uncertainty about the The requirements of the power subsystem are very specific based on what every other subsystem needs. Unfortunately there is uncertainty about the power requirements for many subsystems at this point, and some have no estimate at all yet. As the other subsystems are better defined, the power power requirements for many subsystems at this point, and some have no estimate at all yet. As the other subsystems are better defined, the power subsystem estimate will need to be modified to stay current.subsystem estimate will need to be modified to stay current.

i.i. The thermal subsystems of the orbiter and lander have been calculated based on mass ratios of thermal subsystems on Earth orbiting satellites. This The thermal subsystems of the orbiter and lander have been calculated based on mass ratios of thermal subsystems on Earth orbiting satellites. This does not result in a very accurate approximation; data from the ISS and the space shuttle should be gathered. Additionally, a simple mathematical does not result in a very accurate approximation; data from the ISS and the space shuttle should be gathered. Additionally, a simple mathematical model of the thermal balance will need to be performed to verify other estimates. These two tasks will greatly improve the quality of the estimates.model of the thermal balance will need to be performed to verify other estimates. These two tasks will greatly improve the quality of the estimates.

j.j. Further research needs to be completed on the weight of the actual systems of ECLSS. For example, the exact weight of the molecular sieves Further research needs to be completed on the weight of the actual systems of ECLSS. For example, the exact weight of the molecular sieves collecting the excess carbon dioxide, the weight of the equipment used in the electrolysis and thermoelectric regenerative processes of wastewater, collecting the excess carbon dioxide, the weight of the equipment used in the electrolysis and thermoelectric regenerative processes of wastewater, and the dimensions and mass of the refrigerating units/storage areas for food.and the dimensions and mass of the refrigerating units/storage areas for food.

k.k. The multispectral imagery aspect of the scientific instruments needs to be investigated further. There may be an alternative method to complete the The multispectral imagery aspect of the scientific instruments needs to be investigated further. There may be an alternative method to complete the same tasks but with a significant drop in weight.same tasks but with a significant drop in weight.

l.l. For the synthesis subsystem, we need to determine the volume of the system as a whole. We are currently assuming that if the system is done For the synthesis subsystem, we need to determine the volume of the system as a whole. We are currently assuming that if the system is done creating propellant by the time the crew arrives, it should have no problem creating sufficient oxygen and water to keep them supplied during their creating propellant by the time the crew arrives, it should have no problem creating sufficient oxygen and water to keep them supplied during their stay. This assumption will have to be verified.stay. This assumption will have to be verified.

Future Work (seriously)Future Work (seriously)

Power Estimates for ALL subsystemsPower Estimates for ALL subsystemsReduce Mass to adhere to Magnum Reduce Mass to adhere to Magnum

BoosterBoosterDetailed Structural design and Detailed Structural design and

optimizationoptimizationMore accurate cost analysisMore accurate cost analysis

Questions?Questions?