PowerPoint PresentationSlide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21Slide 22Slide 23Slide 24Slide 25Slide 26Miniaturization of Planetary Atmospheric Probes Tony ColapreteNASA AmesHistory of atmospheric entry probes and scienceWhat probes have flownWhat have they measuredWhat were their limitationsBuilding an entry probeSurvival First, Measure LaterTechnological (and Physical) LimitationsChanging the paradigmThe curse of Galileo - Hand-me-down scienceEnabling Sensors & TechnologyPico probes - New Architectures and Systems“Outline”Credits: Gary A. Allen, Jr., William H. Ailor, James O. Arnold, Vinod B. Kapoor, Daniel J. Rasky, Ethiraj VenkatapathyHistory of planetary entry “probes”Since the 1960’s:Mercury,Gemini, Apollo, Soyuz , etc. (Earth)PAET (Earth)Pioneer Venus, Vega, Venera (Venus)Viking, Pathfinder, MER, DS-2 (Mars)Galileo (Jupiter)Huygens (Titan)Future (on the books):Phoenix Lander (Mars)Mars Science Laboratory (Mars)ExoMars – ESA (Mars)Talked about:Venus SAGETitan Aerobot/RoverJupiter, Saturn & NeptuneViking (1976)Galileo (1995 )Pioneer-Venus (1978) PAET (1971), An Entry Probe Experiment in the Earth’s AtmosphereM = 62 kg, Minst = 14 Kg, Rb = .914 m Atmospheric Science: PAET, Pioneer-Venus, Viking, Galileo and HuygensState-of-the-Art (16 years ago): HuygensProbe specifics:• 2.7 m diameter heat shield• Total Probe mass of 349 kg• 6 instruments (49 kg or 14%)All In-Situ Mars Atmospheric Data…Viking 1 & 2:• Atmospheric state variables during entry (direct). • 5 minutes eachPathfinder and MER:• Atmospheric state variables during entry (derived).• 5 minutes eachPhoenix:• Atmospheric state variables during entry (derived).• 5 minutesIn-Situ Mars Atmosphere ProfilingIn All, about 25 minutes has been spent making measurements between the surface and 80 km.And now for the rest of the data…T (K)100 200 300 400 500 600 700 800z (km)1201101009080706050403020100clouds?Venus Profile Titan ProfileAnd now for the rest of the data…In all, planetary entry probes have measured ~14 individual profilesThe limitations of entry science• Up to this point it is very costly in terms of mass, and always mass = $$• Can only afford to fly a few (if your lucky) and usually only one - Statistics of small numbers (e.g., Galileo)• Limited lifetime – poor temporal coverageThe challenge is to change the way probes are done to overcome these limitations!Huygen Mission DesignPayloadRange: 5%-25%Aeroshell (TPS)Range: 3% - 50%Aeroshell (strcutures)Range: 5% - 12%Aeroshell ParachuteRange: 2% - 5%Power/Thermal/ComRange: 5% - 20%Orbit Insertion (Propulsion & Fuel)Range: 15% - 40%Spacecraft/Bus/ ComEntry ProbeRange: 25% - 40%Range: 25% - 40%Spacecraft Mass fraction Probe mass fractionCassini Spacecraft ComponentsAtmospheric Entry Mission & Probe DesignMission Design Considerations:•Intended Science – Where are you headed?•Key Factors: Mass, Volume, Power, Design Complexities (risk) and Cost •Science payload (mass, power, etc) significantly impact both mission architecture and hardware (mass, power, complexity and cost) – Drives Probe SizeGalileo – A flight through a nuclear blastAbout 50% of the probe was TPSJovian Entry TPS Study• Calculations by Dr. G. Allen / M. Tauber, ELORET based on Engineering Code by Tauber, et. al. • Galileo entry conditions 48 Km/sec, - 6.64o E. angle, equatorial entry • Carbon Phenolic TPS - TPS mass fraction is insensitive to entry probe size • Science mass available for microprobe approx. 1 kgGalileo: Probe Mass: 338 kg, Science Mass: 8.3% of Entry Probe massBase Radius: 1.28 mmicroprobe0.4800.4850.4900.4950.5000.5050.5100.5150501001502002503003500.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1MassTPS/MassentryEntry mass (kg)Ballistic coefficient,  (kg/m2)Rbase/Rbase(Galileo)TPS mass fractionEntry massDesigning for HellThe gas giants present extreme performance limits to TPSPascal Sample Network ConfigurationPascal – A Mars Network Mission Using Micro ProbesPascal Probe Deployment SequencePascal – A Mars Network MissionProbe Entry System0.5 mScience Station- 70° half angle cone- Hemispherical backshell- 20 kg entry mass - RHU poweredPascal – A Mars Network MissionPascal Carrier S/C accommodates 24 Probes with a Delta III or IV Launch VehicleStowed in D3940 FairingFixed Solar ArrayADCS and Telecom ComponentsPower and C&DH ComponentsHydrazine ThrustersMGA’s and LGASpacecraft BusProbe Dispenser Panels (4)Pascal EDL SequencePascal EDL SequenceSelforientationSelforientationAft domeseparatesAft domeseparatesParachute deployment separates entry probe from science packageQ = 700 PaM = 1.5 – 2.2Parachute deployment separates entry probe from science packageQ = 700 PaM = 1.5 – 2.2Jettison airbag andinitiate landed operationsJettison airbag andinitiate landed operationsAirbag protects science station at impact – numerous bouncesAirbag protects science station at impact – numerous bouncesAirbag inflates immediately after chute deploymentAirbag inflates immediately after chute deploymentEntry•Speed = 6 km/s•Landing in 4 minutesEntry•Speed = 6 km/s•Landing in 4 minutesChute separates after first impactChute separates after first impactPascal – A Mars Network MissionPascal requires several enabling technologies/developmentsLandingSphereSensor BoomsWindTemperaturePressureAccelerometersGyroscopesEnabling Sensors - Venus SAGEIMU & MoutherboardProvides information on all atmospheric state variables, stability, and winds during descent and landing.Atmospheric Structure Investigation2.54 cmGSFC 1/ 2 mm.GSFC Research thrust: one kg/one Wmass spectrograph with capability ofCassini/Huygens technology 17 kg/ 15WGSFC developmental time offlight mass spectrograph core 50 gm, 10 cm lengthJamieson & P. Roman/GS FC; L. Delizet,/ARCCassini/Huygens ion sourceThe rmionic electron gunCNT based ion source unde rgoing evaluation 2.54 cmGSFC 1/ 2 mm.GSFC Research thrust: one kg/one Wmass spectrograph with capability ofCassini/Huygens technology 17 kg/ 15WGSFC developmental time offlight mass spectrograph core 50 gm, 10 cm lengthJamieson & P. Roman/GS FC; L. Delizet,/ARCCassini/Huygens ion sourceThe rmionic electron gunCNT based ion source unde rgoing evaluation Enabling Sensors - Amazing Shrinking SensorsA miniaturized mass spectrometerModular reentry probe:• Conduct flight-testing of an