ERV 4 Fall 2003 Sean M. Barraclough Benjamin R. Eastmond Jessica E. Gatto Matthew F. Kauffmann Joel D. Richter Amber M. Wilson The Pennsylvania State University Aerospace 401

ERV Configuration

Mission Architecture

Structures Cylindrical Design Cylindrical Design Monolythic Monolythic Dampening Dampening Docking Adaptor Docking Adaptor Large Space Uses Large Space Uses Food Storage Food Storage Computer and Communications Equipment Computer and Communications Equipment Entertainment Entertainment

Structures Friction Stir Welding Friction Stir Welding Aluminum Metal Matrix Composites Aluminum Metal Matrix Composites Magnum Launch Vehicle Magnum Launch Vehicle 85,000kg 85,000kg 2 launches 2 launches

Propulsion Liquid bipropellant system using CH 4 as fuel and O 2 as oxidizer Liquid bipropellant system using CH 4 as fuel and O 2 as oxidizer RD-0234-CH = main engine located on lander RD-0234-CH = main engine located on lander T = 442 kN; I sp = 343 sec; m = 390 kg RD-183 = smaller engines used as thrusters RD-183 = smaller engines used as thrusters T = 9.80 kN; I sp = 360 sec; m = 60 kg

Ground Control Dedicated Ground System Dedicated Ground System Co-located MCC, POCC, SOCC Co-located MCC, POCC, SOCC Combinations POCC and SOCC Combinations POCC and SOCC Back-up Ground Station Back-up Ground Station Manned by minimum number of staff Manned by minimum number of staff

Communications Deep Space Network Deep Space Network High Gain Antennae (HGA) High Gain Antennae (HGA) Two Low Gain Antennae (LGA) Two Low Gain Antennae (LGA) Total Communications System Total Communications System One HGA, 2 m diameter One HGA, 2 m diameter Two LGA, 0.25 m diameter Two LGA, 0.25 m diameter Receiver and transmitter, combined measuring 5 m by 2 m Receiver and transmitter, combined measuring 5 m by 2 m Total weight: 160 kg Total weight: 160 kg

Communications Mars Reconnaissance Orbiter Mars Reconnaissance Orbiter Launch 2005 Launch 2005 Intermediary link between ERV and DSN Intermediary link between ERV and DSN Guidance system to help ERV when entering Mar’s orbit Guidance system to help ERV when entering Mar’s orbit Beacon System Beacon System Monitor overall health of ERV going to Mars Monitor overall health of ERV going to Mars Sends out one of 4 carrier tones indicating ERV health Sends out one of 4 carrier tones indicating ERV health Easily detected, low cost, frees up space on DSN Easily detected, low cost, frees up space on DSN Orbiter Lander Mars Recon Earth/ DSN Communications Relay System (when in Mars orbit) Beacon System

Command and Data Handling Completely redundant, no single point failure Completely redundant, no single point failure Space Shuttle uses 5 computers, 2 running, 3 as back-up Space Shuttle uses 5 computers, 2 running, 3 as back-up Space Shuttle computers Space Shuttle computers Mass: 29 kg Mass: 29 kg 550 W power 550 W power Our system if trends in new technology continue Our system if trends in new technology continue 9 times faster 9 times faster 30% less electricity 220W power 30% less electricity 220W power 60% less mass 7kg per computer 60% less mass 7kg per computer Totals Totals 70kg mass 70kg mass 1375W electricity 1375W electricity

Guidance, Navigation and Control Attitude control Attitude control Navigation Navigation CT-63X Star Sensor by Ball Aerospace & Technologies Corp, model CT-633 CT-63X Star Sensor by Ball Aerospace & Technologies Corp, model CT AXIS STABILIZED CASSINI SPACECRAFT CCD Imaging System CT-63X

Guidance, Navigation, and Control Inertial Reference Frame Devices Inertial Reference Frame Devices Three gyros that provide attitude reference similar to system of space shuttle Three gyros that provide attitude reference similar to system of space shuttle Mars Reconnaissance Orbiter Mars Reconnaissance Orbiter Total weight of subsystem: 100kg Total weight of subsystem: 100kg

Power Subsystem Orbiter Orbiter Solar array Solar array Lander Lander Nuclear Fission Reactor Nuclear Fission Reactor

Power Requirements (kWe) OrbiterLander Structure N/AN/A Propulsion Power (provided) (20)(140) Thermal Command and Data Synthesis N/A140 Communication0.06 Life Support Scientific Instruments Guidance Nav. & Control 0.1 Power Requirements Table

Thermal ISS Radiator Lander Lander Powered down during interplanetary cruise Powered down during interplanetary cruise Nuclear reactor: large series of pipes Nuclear reactor: large series of pipes to dissipate heat when on Mars to dissipate heat when on Mars Fuel synthesis neutral in heat requirements Fuel synthesis neutral in heat requirements Orbiter Orbiter Maximum solar radiation when in Earth orbit Maximum solar radiation when in Earth orbit Will generate up to 46kW of rejected heat Will generate up to 46kW of rejected heat Average satellite uses 3.4% of dry mass for thermal subsystem Average satellite uses 3.4% of dry mass for thermal subsystem

Environmental Control and Life Support Oxygen regenerated through electrolysis of H 2 O Oxygen regenerated through electrolysis of H 2 O Reusing CO 2 molecular sieves Reusing CO 2 molecular sieves Purifying H 2 O through thermoelectric process Purifying H 2 O through thermoelectric process Ionization & photoelectric flame detectors; CO 2 repressant Ionization & photoelectric flame detectors; CO 2 repressant Dehydrated food Dehydrated food Crew composed of 2 men & 2 women Crew composed of 2 men & 2 women Group testing under stressful conditions Group testing under stressful conditions Sandy beach theme within ERV Sandy beach theme within ERV Personal locker space Personal locker space PhysiologicalPsychological

Scientific Instruments Thermometers, Lidar device, accelerometers, altimeters, seismometers, & pressure sensors Thermometers, Lidar device, accelerometers, altimeters, seismometers, & pressure sensors -M = 570 kg Multispectral imagery Multispectral imagery -M = 250 kg Robotic Chemical Analysis Laboratory Robotic Chemical Analysis Laboratory -M = 2.4 kg

Synthesis Requirements Requirements Create 80,000 kg propellant within 780 days Create 80,000 kg propellant within 780 days Lightweight Lightweight Reasonable power draw Reasonable power draw Result Result S/E-RWGS System S/E-RWGS System Mass = 490 kg Mass = 490 kg Power requirement = 140 kW Power requirement = 140 kW Hydrogen requirement = 4,570 kg Hydrogen requirement = 4,570 kg Mass Savings: % Mass Savings: %

Cost Analysis

Future Work 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 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 minimize our mass per component. This will be a lengthy process that will require detailed structural analysis of the ERV and its individual components. 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 addition, the launch location should be decided. 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 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.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 actual layout of our ground system determined. 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 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 need to find and actual transmitter and receiver system to run the antennas. f.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 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. 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 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 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. h.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 subsystem estimate will need to be modified to stay current. i. 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 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.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, and the dimensions and mass of the refrigerating units/storage areas for food. k.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. 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 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.

Future Work (seriously) Power Estimates for ALL subsystems Power Estimates for ALL subsystems Reduce Mass to adhere to Magnum Booster Reduce Mass to adhere to Magnum Booster Detailed Structural design and optimization Detailed Structural design and optimization More accurate cost analysis More accurate cost analysis

Questions?