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ASTEROID MISSION PLAN. Contractor 3 Eric Hickernell Chris Martin Luis Medina Lee Moreno James P. Quinn Sam Stephens Zach Sunberg. Introduction. Mission Statement Asteroid Selection Orbit Analysis Propulsion Selection Power Systems Spacecraft Design Mission Experiments Human Factors.
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ASTEROID MISSION PLAN Contractor 3 Eric HickernellChris Martin Luis Medina Lee Moreno James P. Quinn Sam Stephens Zach Sunberg
Introduction • Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors
Mission Statement Our objective is to explore the albedochange asteroid mitigation technique and develop technologies for future long-range space exploration. We will design a mission to send an astronaut team to a Near Earth Asteroid by 2030, collect data and samples, and safely return to the Earth.
Astronaut Team • Commander • Serves as the leader, decision-maker, and pilot. • Mitigation Specialist • Primary expert in charge of performing mitigation technique experiments. • Geologist/Physicist • Collects samples and data about the composition of the asteroid and determine gravity-field and other parameters. • Medical Expert • Monitors astronaut health and collects data concerning the effects of zero-gravity, artificial gravity, and radiation on the human body. Each astronaut should be able to perform the duties of another astronaut in case of unexpected emergency.
Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors Quinn
Important Parameters • The asteroid should be of significant and known size. • The asteroid should also have enough surface area to test the albedo change mitigation techniques. • The asteroid should be relatively easy to get to. • The parameters we set are: • a<1 AU • i< 5degrees • Aten, Apollo Classification • Low relative velocity w.r.t. Earth • The asteroid should be a possible threat to Earth.
Asteroid candidates* • 5604 (1992 FE) • Diameter = 0.55 km • a = 0.93 AU • i = 4.79 deg • 9942 Apophis (2004 MN4) • Diameter = 0.270 km • a = 0.92 AU • i = 3.33 deg • 1999 AO10 • Diameter = 57 m • a = 0.911 AU • i = 2.62 deg • 3361 Orpheus (1982 HR) • Diameter = 0.30 km • a = 1.21 AU • i = 2.68 deg • 2000 SG344 • Diameter = 0.30 km • a = 0.97 AU • i = 0.11 deg • 1999 MN • Diameter = 200 m • a = 0.67 AU • i = 2.01 deg *From JPL Small Body Database Browser
Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors Medina
Orbit Analysis • 1999 AO10 • Closest Approach: Feb. 12, 2026 • Min Dist: 0.026 AU • Relative Velocity: 2.6 km/s • Orbit Calculation Results for Constant Low Thrust* • 205 day outbound, 160 day return • 11 day stay at asteroid • Structural & Equipment Mass = 180 MT • Propellant Mass required = 7 MT • Max Thrust needed ~ 55 N Arrive at Asteroid Depart Asteroid Ephemerides of asteroids and Earth from JPL’s Horizons system *Euler Hill Approximation with the Earth as primary body Earth
Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors Stephens
VASIMR • Power range of the VASIMR is up to its full operational capability of 200 kW • Use multiple VASIMR engines powered by combination of solar array and Nuclear Reactor to ionize fuel into plasma. • Use Hydrogen as fuel • Can mitigate radiation effects
Constant Thrust Engine Trade Study • Magnetoplasmadynamic propulsion • Highest known thrust of any known type of electric propulsion • Not popular because they operate on a large power scale • Flown in space onboard Japanese Space Flyer Unit in 1995 - 96
Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors Sunberg
SAFE 400 Space Fission Reactor • Safe Affordable Fission Engine • Developed quickly and affordably using existing technology • Nuclear reactor coupled with a Brayton cycle gas generator • Approximate total mass of 1200kg including gas turbines • Reactor creates 400 kW of heat generating 100 kWe of electricity • Information we used: • Expected reactor heat to electricity efficiency of 25 % • Gas temperature of ~1000 K => radiator temperature of 800K Reid, R.S., Kapernick, R.J. “SAFE Gas Turbine Cycle Primary Heat Exchangers” Space Technology and Applications International Fomm-STAIF 2002, pp. 722-725 Poston, D.I., Kapernick, R.J., Guffee, R.M. “Design and Analysis of the SAFE-400 Space Fission Reactor” Space Technology and Applications International Fomm-STAIF 2002, pp. 578-588
Power Systems • Primary Nuclear • Electrical Power: 2000 kWe (Would need about 6000 sq. m of solar panels for this) • Reactor Heat: 8000 kW • Mass: 20 metric tons • Radiator Size: 330sq. m • Secondary Solar Photovoltaic (Emergency) • Electrical Power: 20 kWe • Area: 75 sq. m
Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors Hickernell
Engine Pod Habitation Pod Mitigation Pod Solar Array Communication Dish Telescoping Truss Radiator Fuel Tanks
Spacecraft Design Data • Telescoping trusses: • can extend from 5 feet to 115 feet, approximately 421.4 kilograms each • Habitation pod: • 27 feet long, 10 foot diameter • Mitigation pod: • Same size as habitation pod, but no windows • Engine pod: • 21 foot diameter, 42 feet long • Fuel/water tanks: can equip between 1-8 tanks depending on mission requirements, each tank has a volume of about 178 cubic feet • When trusses are extended, entire ship rotates to create artificial gravity. Extended configuration of the ship is 279 feet wide. Collapsed configuration is 73 feet wide.
Mass Estimates • Masses in Metric Tons
antenna • Parabolic Antenna • Location would be on the capsules. • One on each side for redundancy and for trajectory. • Size would be smaller than capsule due to landing considerations. • Specifications • Max distance traveled away from Earth is 0.05 AU • 3 meter diameter • Auto-tracking
S/C : 3.05 m diameter Dish: 3.00 m diameter Placement
Antenna Sizing Analysis Operating Area Distance of 0.3 AU Distance of 0.05 AU
Landing Options Our Approach: Land Entire Ship
Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors Moreno
Primary Objective • Albedo Change Experiment • Study the albedo of target asteroid • Decide if we need to raise/lower orbit • Maneuver close to asteroid and hover • Sunlit surface of asteroid will have positive charge • Shoot fine particles with negative charge at surface; the particles will be attracted to asteroid surface • Particles will stick and cure and change the albedo of asteroid • Small net thrust given by photon emission will raise/lower orbit • Leave beacon to track asteroid and test our prediction models
Secondary Objective • Study effects of Artificial Gravity on astronauts • Further studies of psychological & physiological effects of long term space travel • Identify parameters of asteroid and compare to predicted values • Mineral composition • Size • Mass • Gravity Field • Magnetic Field • Bring back samples for analysis • Perform other scientific experiments during transit • Determine what aspects of mission will improve future missions
Artificial gravity becomes more “normal” with increasing radius 0.035 g Limit of low traction 1g Comfort zone 4 rpm Onset of motion sickness 6 m/s rim speed Apparent gravity depends on direction of motion Artificial Gravity Gravity: 0.3g Radius: 40 m Angular Velocity: 2.6 rpm
Mission Statement • Asteroid Selection • Orbit Analysis • Propulsion Selection • Power Systems • Spacecraft Design • Mission Experiments • Human Factors Martin
Human factors Psychological • Personal sleeping pods • Space / Astronaut is 6.8 m3 • Strict Schedules with free time • Video Email • Recreational Activities • Food Options Physiological • Radiation Protection • Sleep Disturbance • Cardiovascular Deconditioning • Bone/Muscle Loss • SAS
Radiation protection • Use hydrogen rich polyethylene as radiation shielding • Polyethylene is 50% better at shielding solar flares and 15% better for cosmic rays than aluminum
Exercise equipment • Cycle Ergometer • Similar to stationary bike • Treadmills • Can be loaded with 66% to 100% of body weight • Cardiovascular exercise • Advanced Resistance Exercise Device (aRED) • Astronauts can perform heel lifts, squats, deadlifts • Modified Bowflex Revolution • Can perform over 100 exercises to work out all parts of the body • Can be modified to fold up to save space • Rowing Machine • Full Body Workout • Great aerobic workout • Good for joint health
Life support systems Urine Treatment • Distillation • Unusable liquid brine • No noticeable taste difference Water Treatment • Particle Filtration • Ion Exchange • Carbon Absorption • Catalytic Oxidation • Iodine Addition Considerations • Iterative Recycling • Special Soaps Air Treatment • Air revitalization • Water electrolysis • Quality control sensors Considerations • 1 Liter / astronaut / day • Approx. 1500 Liters for year long trip
conclusion • Overall Mission Features: • Study the effects of Albedo Change Mitigation Technique • Study Artificial Gravity and long term effects of space on human physiology • Validation of the VASIMIR technology • Further validation of nuclear power in space • Spacecraft can be left in orbit and reused multiple times
Required food Assumptions • Daily Diet of 2500 Calories • 376 day trip • 4 crew members Food Results • 864 kg will be needed • 1000 kg will be taken
MPD: Diatomic hydrogen propellant data ISP ~ 12.5x10^3 [sec] Thrust ~ 60 N Power ~ 15 [kA] x 450 [V] = 6750 [kW] Source: Journal of Propulsion and Power, Vol. 17 No. 4. Sept/October 2001.
Landing (Rocky) Additional Spring-Loaded-Cam or Inflate-in-a-Cavity Anchors Initial Drilled Anchor
Landing (Rubble Pile) Initially held in place by rcs thrusters Epoxy Foam that fills in cavities and bonds to pieces
Artificial Gravity Sizing Tradeoffs: Radius Low = smaller truss for stiffness, axial strength High = more gravity Angular Velocity Low = less required thrust to spin up High = more gravity Desired Gravity: 0.3 g Radius = 40m Angular Velocity = 2.6 rpm
Asteroid Exploration Instrumentats • Laser range finder - 1.54 kg • Thermographic camera - 0.88 kg • Microscopic imager – 3 kg • Bolometer – 1.5 kg • Panorama camera – 1.3 kg • Mobile mining drill – 20 kg • Magnetometer – 0.1 kg • Fiberglass shovel – 3 kg
Onboard Experiments • Emergency Scenario Simulation and Drills • Surface, Water, and Air Biocharacterization (SWAB) • Monitors number of microorganisms and allergens on the spacecraft • Provides astronauts ample warning of organisms they may encounter • Transgenic Arabidopsis Gene Expression System (TAGES) • Study of stresses on plants due to space environment • Study effects due to drought, inadequate light, and uneven temperature • Microgravity Acceleration Measurement System (MAMS) • Study of vibrations of the spacecraft due to crew and equipment movements • Materials Test (MT) • Study of the effects of long term exposure of materials to space environment • Electrostatic Radiation Shielding Test (ERST) • Study of the feasibility and effectiveness of electrostatic shielding for future space flight
Delete Slide? Maybe add in another slide that says a strict schedule will be in place
Possible additions • Modified Bowflex Revolution • Can perform over 100 exercises to work out all parts of the body • Can be modified to fold up • Save space • Rowing Machine • Full Body Workout • Great aerobic workout • Good for joint health Merge with previous slide?
Trade Study • 3361 Orpheus (1982 HR) • 360 day travel, 10 day stay • MP = 37 MT • Max Thrust: 338 N • Mf =95 MT • 99942 Apophis • 360 day travel, 11 day stay • MP = 14.33MT • Max Thrust: 42 N • Mf = 15 MT