IPPW Bio: Robert Dillman BS Aerospace Engineering, University of Virginia 1989; Masters of Materials Science, University of Virginia 1997 NASA

Transcription

1 IPPW Bio: Robert Dillman BS Aerospace Engineering, University of Virginia 1989; Masters of Materials Science, University of Virginia 1997 NASA Langley Research Center, Hampton VA, since years of Space Shuttle payloads: mechanical design & analysis; assembly, testing, crew training, & installation into Shuttle bay Since 2000: EDL hardware development and studies Mars Sample Return (MSR) Earth Entry Vehicle (EEV) for MSR 2003/2005 Project Orion boilerplate capsule for Pad Abort 1 test Inflatable Reentry Vehicle Experiment - II (IRVE-II) & -3 (IRVE-3), 3m diameter HIAD Operations Lead for LeO Flight Test of an Inflatable Decelerator (LOFTID), 6m diameter HIAD

2 NASA Planetary Science Deep Space SmallSat Studies Kunio Sayanagi, Principal Investigator Hampton University Robert A. Dillman, Chief Engineer NASA Langley Research Center Boulder, Colorado, USA

3 Planetary Science Deep Space SmallSat Studies (PSDS3) Funded studies of small secondary payloads to return science from solar system bodies other than Earth or Sun Intended to explore the missions possible with CubeSat/SmallSats Mission mass < 180 kg, Mission funds < $100M Study funds < $500K Nov 18, 2016: Proposed concept study of Small Next-generation Atmospheric Probe (SNAP) for deployment from mission orbiting or flying by gas giants Estimated 30 kg, 0.5 m diam probe with HEEET & PICA TPS In-sutu measurement of vertical distribution of clouds & chemical species, temperature/pressure/density profiles, & wind speeds, down to 5 bars SNAP transmits data to carrier spacecraft for relay to Earth Mar 23, 2017: Selected for study 2

4 Study Team Kunio M. Sayanagi (PI) Robert A. Dillman David H. Atkinson Amy A. Simon Michael H. Wong Thomas R. Spilker Sarag Saikia Archit Arora Jing Li Hampton University NASA Langley Research Center Jet Propulsion Laboratory NASA Goddard Space Flight Center University of California, Berkeley Independent Consultant Purdue University Purdue University NASA Ames Research Center NASA Langley Engineering Design Studio: Angela Bowes (trajectory), Alex Scammell (thermal), Steve Bowen (power), Steve Horan (comm), Chris Thames (sensors), Lawrence Taylor (mechanical config) 3

5 Mission Design Assumptions 1. Example Carrier Mission: Uranus Orbiter with Probe Mission Architecture #5 by Ice Giants Flagship SDT: 1913 kg Uranus orbiter with 50 kg science instrument package 321 kg probe ( Primary Probe = PP) Launch 5/25/2031, 12-year cruise to Uranus, 142-day initial orbit 2. Add SNAP as a secondary probe Not a duplicate of the primary; no mass spec, etc 3. Minimize effect on primary mission 4. Deliver PP and SNAP with large spatial separation e.g. day & night sides, or different hemispheres & seasons 5. Probe trajectories must enable data relay to carrier spacecraft at different times to allow re-use of comm system 4

6 SNAP Science Instruments Instrument Measurement Mass Power NanoChem Atmospheric Structure Instrument Ultra-Stable Oscillator Atmospheric Composition Pressure Temperature Acceleration Doppler Wind Experiment SNAP Data Return 1.0 kg 0.1 W 1.08 Mbit 1.3 kg 5.7 W 6.25 Mbit 1.7 kg 3.2 W 0.05 Mbit (Housekeeping Only) Total 4 kg 9 W 7.35 Mbit 5

7 NanoChem: Chip-based Sensor Measures Changes in Resistivity in response to gas composition Sensor Heads can be arrayed up to 16 x16 grid on a single chip Under Development at NASA Ames (PI: Jing Li) NanoChem Advantages: Small Sensor Package Low Mass, Low Power Can operate without Vacuum Pump NanoChem response to ammonia 6

8 NanoChem: TRL = 4 Today 7 Launched and Operated in Space Navy MidSTAR-1 satellite in 2007 Environmental Monitoring on ISS Sensitivity demonstrated for: CH 4, H 2 O, and NH 3, among others in Mars and Earth conditions Need to develop sensitivities for: H 2 S in Giant Planet Conditions Analyte Sensitivity/Detection Limit CH 4 1 ppm in air Hydrazine 10 ppb tested NO ppb in air NH ppm in air SO 2 25 ppm in air HCl 5 ppm in air Formaldehyde 10 ppb in air Acetone 10 ppm in air Benzene 20 ppm in air Cl ppm in N 2 HCN 10 ppm in N 2 Malathion Open bottle in air Diazinon Open bottle in air Toluene 1 ppm in air Nitrotoluene 256 ppb in N 2 H 2 O ppm in air 7

9 Uranus Entry Locations Accessibility of Entry Locations - Trajectory gives access to a wide range of latitudes and spatial distribution for the entry probes - One probe can enter the night side and the other on the day side (After 2028 Northern Summer Solstice) 8

10 SNAP EDL Profile Entry heat pulse & deceleration Deploy separation parachute at 50 mbar (76 km above 1 bar), pull away backshell Release heat shield at 100 mbar Use separation chute to pull out smaller chute, allowing descent module to reach deeper into atmosphere while within comm window Should reach 10 bar depth before LOS, giving margin beyond science goal of 5 bars 9

11 Acceleration [g] Air Speed [Mach] Heating Rate [W/cm 2 ] Dynamic Pressure [kpa] Entry & Descent Analysis 3,500.0 Heating Rate [W/cm 2 ] 3, , , , , Time [sec] Acceleration [g] Time [sec] Dynamic Pressure [kpa] Time [sec] Air Speed [Mach] Time [sec] 10

12 Probe Mass Summary Component Mass [kg] Subtotal Mass Forebody TPS (HEEET) + Structure 5.74 Aftbody TPS (PICA) + Structure + Separation Mechanism 4.15 Aeroshell Total kg Descent Module Structure 2.1 Parachutes 0.4 Science Instruments 4 Engineering Subsystems 4.2 Descent Module Total 9.85 kg Atmospheric Entry Mass Total kg Mass Margin (25%) 6.12 kg Total Probe Mass 30 kg 11

13 Probe Power Summary Sub-system/ Instruments Ultra-Stable Oscillator ASI Nano-Chem Sensor Avionics Radio Transmitter Accelerometers Total Power 3.2 W 5.7 W 0.1 W 4 W 50 W 0.1 W 63.1 W Assuming use of x3 RHUs for heat during coast Battery-powered heaters are also possible for 30-day coast: Li-Ion (current, 145 Wh/kg) = 21 kg Li-Ion (future, 400 Wh/kg) = 7.5 kg Li/CFx (639 Wh/kg) = 4.7kg Energy Requirement, Wh Battery Mass, kg Number of Batteries

14 Probe Design Summary 0.5 m diameter, 45 sphere-cone heat shield Fore-body TPS = HEEET; Aft-body TPS = PICA Probe mass fits within 30 kg budget, including 25% growth allowance Probe released ~30 days before entry (from ~142-day orbiter orbit) Prograde entry with EFPA between -40 and -45 and V = 22.4 km/s Orbiter distance 36,000 13,000 km during SNAP mission (~40-mins contact time) Short distance range enables sufficient data rate Deceleration and aerothermal conditions all well within design limits Entry Conditions of SNAP Parameter Values Peak Heat Rate, W/cm Stagnation Pressure, bar Heat Load, J/cm Peak Inertial Load, Earth G s

15 SNAP Design Summary Dual-Probe Trajectory Solutions Found SNAP Mass: 30 kg (Instrument Mass = 4 kg) Total Data Return = 7.3 Mbit Total Mass Addition to Carrier Mission: 72.3 kg Total Estimated Cost: 74.8M (FY18$) Enabling Technologies: NanoChem & HEEET Enhancing Technologies: Better Batteries SNAP: Enable Future Multi-Probe Missions 14

16 Questions? 15