Intelligent Space Systems Laboratory ISSL The University of Tokyo One-year Deep Space Flight Results of the World’s First Full-scale 50-kg-class Deep Space Probe PROCYON and Its Future Prospects

Earth imagers captured during Earth re-encounter

67P/Churyumov–Gerasimenko comet *Ryu Funase, Takaya Inamori, Satoshi Ikari, Naoya Ozaki, Shintaro Nakajima, Kaito Ariu, Hiroyuki Koizumi (Univ. of Tokyo), Shingo Kameda (Rikkyo Univ.), 1

Atsushi Tomiki, Yuta Kobayashi, Taichi Ito, Yasuhiro Kawakatsuwww.space.t.u(JAXA)-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Small spacecraft development at Univ. of Tokyo

PROCYON(2014): 65kg XI-V (2005): 1kg The first interplanetary XI-IV (2003): 1kg Nano-JASMINE: 33kg for tech. demo. for Astrometry micro-spacecraft The first CubeSat Still operational (>9yrs) Still operational (>12yrs) (space science mission) PRISM (2009): 8kg Awaiting launch… for remote sensing (20m GSD) Still operational (>6yrs) 60kg micro-sats for remote sensing (6m GSD) Hodoyoshi-1 Hodoyoshi-3 and Hodoyoshi-4 (2014)

2 www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Beginning of PROCYON mission “Rideshare” interplanetary launch opportunity with Hayabusa-2 was announced. Joint mission proposal by U of Tokyo and JAXA was approved (small sat experiences + deep space exploration experiences) How small auxiliary payloads are mounted on the rocket

Micro satellites can be PAF Hayabusa2 installed here

Support structure © JAXA to implement micro satellites 3 www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo

Trajectory plan to flyby asteroid “2000 DP107”

12/03/2014 Launch 12/03/2015 Earth swingby

(Sun-Earth fixed rotational frame)

2016/05/12 Asteroid flyby

What is the asteroid “2000 DP107”?  Binary asteroid (asteroid with “satellite”)

 PHA (Potentially Hazardous Asteroid) 4

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Real-time Line-of-sight image-feedback control to track asteroid direction

Rotate

+Z

+X +Y 1-axis Rotatable Telescope (for Optical Navigation and flyby observation) Observable Star Magnitude: 12 Surface resolution: ~1[m]@10km Rotational speed: <55[deg/s] (10km/s @10km) 5 www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Mission of PROCYON Primary mission • Demonstration of a micro-spacecraft bus system for deep space exploration 3. Asteroid flyby (including propulsion, deep space communication and (Jan. 2016 or later) orbit determination system) Secondary (advanced) missions • GaN-based high efficiency SSPA • Demo of a novel DDOR (Delta Differential One-way SUN Range) orbit determination method (“Chirp DDOR”) • Deep space maneuver to perform Earth swing-by and trajectory change to target an asteroid flyby 2. Earth swingby • Optical navigation and guidance to an asteroid (Dec. 2015) • Automatic Line-of-sight image-feedback control to track asteroid during close fast flyby [Scientific observation mission] 1. Launch • Wide-view observation of geocorona (ultra-violet (Dec. 3, 2014 together with Hayabusa-2) emission from hydrogen atmosphere) with Lyman alpha imager from a vantage point outside of the Earth’s geocorona distribution 6

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo External View of PROCYON

HGA (25dBi) SAP LGA (CMD) 1.5 m RCS (Xe cold gas) 1.5 m LGA (TLM)

+Z RCS (Xe cold gas) RCS (Xe cold gas) +Y Telescope +X

MGA(14dBi) 0.55 m Ion thruster (Xe)

Star Geocorona Imager Tracker (LAICA)

RCS (Xe cold gas) +Y +Z

LGA (CMD) +X RCS (Xe cold gas) LGA (TLM) 7

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Actual outlook of PROCYON

(SAP stowed)

(SAP deployed) 8

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Internal configuration

0.55 m

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www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo One-year development schedule

Year 2013 2014 Month 9 10 11 12 1 2 3 4 5 6 7 8 9 10 11 12 ▲ ▲ Launch approval S/C Delivery Start of S/C Development ▲ Conceptual study & Launch System design EM/STM test (Dec. 3) (05/2013~) FM (component)fabrication

Schedule FM integration & test • Thermal Vacuum test • Vibration/Shock test • I/F test • “Table sat” test • Ion thruster test • Thermal Vacuum test EM: Engineering Model • Vibration test STM: Structure and Thermal Model • Separation shock test FM: Flight Model Very small team (20~30 staffs and students at one place) enabled quick decision making for quick development. Do not try to optimize the design. Find a feasible solution. 10

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo

Deep space flight results

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www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Primary mission results Demonstration of micro-spacecraft bus system 0.12 for deep space exploration (requires 2~3 months)

0.10 Unloading maneuver Power generation/management (>240W) 0.08  Thermal design to accommodate wide Norm of the angular momentum/Nms 0.06 range of Solar distance (0.9~1.5AU) and

0.04 power consumption mode (electric prop. SUN on/off, 137W/105W))  Attitude control (3-axis, 0.01deg stability)

25.00  Deep space communication & navigation

Doppler shift/mm s-1 20.00 from ~60,000,000 km Earth distance  15.00 366±3 μN Deep space micro propulsion system T. coefficient: 0.927  RCS for attitude control/momentum 10.00 LaunchIon beam current/mA management (8 thrusters) 5.00 (Dec. 3, 2014, together with Hayabusa-2)  Ion propulsion system for trajectory 0.00 control (1 axis, Isp=1000s, thrust>300uN) 12 www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Secondary (advanced) mission results Completed • GaN-based SSPA (Solid-State Power Amplifier) with the world’s highest RF efficiency (>30%) Completed • Demonstration of a novel DDOR (Delta Differential One-way Range) orbit 3. Asteroid flyby determination method (“Chirp DDOR”) to (Jan. 2016 or later) improve conventional DDOR orbit determination accuracy Partially • Deep space maneuver for Earth swing-by and completed trajectory change to target an asteroid flyby SUN • Optical navigation and guidance to an asteroid • Automatic Line-of-sight image-feedback 2. Earth swingby (end of 2015) control to track asteroid during close fast flyby [scientific observation mission] • Wide-view observation of geocorona with Lyα imager from a vantage point outside of the 1. Launch (Dec. 3, 2014 Earth’s geocorona distribution together with Hayabusa-2) 13

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Secondary (advanced) mission results Completed • GaN-based SSPA (Solid-State Power Amplifier) with the world’s highest RF efficiency (>30%) • Demonstration of a novel DDOR (Delta CompletedAchievement of deep space maneuver by the Differential One-way Range) orbit ion thruster (Transition of the closest approach 3. Asteroid flyby determination method (“Chirp DDOR”) to distance to Earth projected on the B-plane) (Jan. 2016 or later) improve conventional DDOR orbit determination accuracy Partially TCM (Trajectory Correction Maneuver) <100km• Deep accuracy space maneuver (3σ) was forachieved, Earth swing -by and completed experimentGuidance usingAccuracy RCS to aw virtualill not be target whichtrajectory satisfied change the requirement to target an for asteroid flyby on B-plane,improved whichSUNby simulatedTCM4: ~ 90 the[km]@3σ final 2000 DP107 flyby guidance stage of the Earth swing-by. • Optical navigation and guidance to an asteroid • Automatic Line-of-sight image-feedback 2. Earth swingby (end of 2015) control to track asteroid during close fast flyby [scientific observation mission] • Wide-view observation of geocorona with Lyα imager from a vantage point outside of the 1. Launch (Dec. 3, 2014 Earth’s geocorona distribution together with Hayabusa-2) 14

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Secondary (advanced) mission results Completed • GaN-based SSPA (Solid-State Power Amplifier) with the world’s highest RF efficiency (>30%) Completed • Demonstration of a novel DDOR (Delta Differential One-way Range) orbit 3. Asteroid flyby determination method (“Chirp DDOR”) to (Jan. 2016 or later) Severalimprove stars conventionaldarker than 12th DDOR magnitude orbit were successfullydetermination detected accuracy by the telescope, which Partially satisfied the requirement for the optical • Deep space maneuver for Earth swing-by and completed navigation and guidance to an asteroid. trajectory change to target an asteroid flyby SUN Partially completed • Optical navigation and guidance to an asteroid • Automatic Line-of-sight image-feedback 2. Earth swingby (end of 2015) control to track asteroid during close fast flyby [scientific observation mission] • Wide-view observation of geocorona with Lyα imager from a vantage point outside of the 1. Launch (Dec. 3, 2014 Earth’s geocorona distribution together with Hayabusa-2) 15

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo

Secondary (advanced)Distance: 4.9×10 6missionkm results Completed • GaN-based SSPA (Solid-State Power Amplifier) with the world’s highest RF efficiency (>30%) Completed • Demonstration of a novelEarth DDOR (Delta Differential One-way Range) orbit 3. Asteroid flyby PROCYON determination method (“Chirp DDOR”) to (Jan. 2016 or later) improve conventional DDOR orbit determination accuracy Partially • Deep space maneuver for Earth swing-by and completed trajectory change to target an asteroid flyby SUN Partially completed • Optical navigation and guidance to an asteroid Partially • Automatic Line-of-sight image-feedback 2. Earth swingby completed (end of 2015) control to track asteroid during close fast flyby [scientific observation mission] Attitude maneuver profile to • AutonomousWide-view observation Earth tracking of geocorona error anglewith was Ly α imager from a vantage point outside of the simulate the1. Launch motion of an asteroid. <0.4deg in this particular environment, which (Dec. 3, 2014 satisfiedEarth’s geocorona the accuracydistribution requirement when the together with Hayabusa-2) flyby altitude is a dozen kilometers. 16

www.space.t.u-tokyo.ac.jp 恒星 Intelligent Space Systems Laboratory ISSL The University of Tokyo Secondary (advanced) mission results Paper under review Completed • GaN-based SSPA (Solid-State Power Amplifier) with the world’s highest RF efficiency (>30%) Completed • Demonstration of a novel DDOR (Delta ~400,000 km Differential One-way Range) orbit Geocoronal3.emission Asteroid (in Rayleigh) flyby on Jan 9, 2015 determination method (“Chirp DDOR”) to Kameda et(Jan. al., in 2016 prep. or later) Apollo 16 improve conventional DDOR orbit [Carruthers et al., 1976] determination accuracy Partially • Deep space maneuver for Earth swing-by and completed trajectory change to target an asteroid flyby SUN PartiallyHydrogen• Optical emission navigation around and 67P/ guidanceChuryumov to an– asteroid completedGerasimenko comet was observed on Sep. 13, Partially2015.• ThisAutomatic comet isLine the-of destination-sight image of-feedback the 2. Earth swingby (end of 2015) completedEuropeancontrol Space to Agency's track asteroid Rosetta during mission. close fast flyby [scientific observation mission] 67P/Churyumov–Gerasimenko comet Completed • Wide-view observation of geocorona with Lyα imager from a vantage point outside of the 1. Launch (Dec. 3, 2014 Earth’s geocorona distribution together with Hayabusa-2) 17

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Secondary (advanced) mission results Completed • GaN-based SSPA (Solid-State Power Amplifier) with the world’s highest RF efficiency (>30%) Completed • Demonstration of a novel DDOR (Delta Differential One-way Range) orbit 3. Asteroid flyby determination method (“Chirp DDOR”) to (Jan. 2016 or later) improve conventional DDOR orbit determination accuracy Partially • Deep space maneuver for Earth swing-by and completed trajectory change to target an asteroid flyby SUN Partially • Optical navigation and guidance to an asteroid completed Partially • Automatic Line-of-sight image-feedback 2. Earth swingby (end of 2015) completed control to track asteroid during close fast flyby [scientific observation mission] Completed • Wide-view observation of geocorona with Lyα imager from a vantage point outside of the 1. Launch (Dec. 3, 2014 Earth’s geocorona distribution together with Hayabusa-2) 18

www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Summary of the flight results • Demonstration of deep space bus system success!

• Scientific mission (geocorona observation) success!

• All the mission were successful except for: – long-time deep space maneuver by the ion thruster – actual asteroid flyby

• Within the very limited development time and budget, we could demonstrated the capability of this class of spacecraft to perform deep space mission by itself and it can be a useful tool of deep space exploration.

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www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo

Future prospects

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www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Possible deep space missions by small sats

Hayabusa/MINERVA(© JAXA) InSight/MarCO(© NASA/JPL-Caltech) PROCYON Nano-sat (1~10~20kg) Micro-sat (~50kg)

Example of appropriate mission type: Example of appropriate mission type: • Mother-ship/daughter-ship mission • Precursor to a larger mission (Human • “Focused” mission planetary exploration, asteroid mining, where etc) • Limited function/performance which requires high performance is/should be admitted • High comm. speed (by limiting the scope of the mission • High power generation and/or limiting the environment • High propulsive capability where the spacecraft should work • High obs. performance/Large aperture, (work only “on-site”) etc 21 www.space.t.u-tokyo.ac.jp Intelligent Space Systems Laboratory ISSL The University of Tokyo Possibility of international collaboration • Co-development of a single spacecraft – Each country provide component(s) in which it has an advantage over others, and a country is responsible for the spacecraft integration – e.g.) Japan has a solid expertise on: • Miniature and high-performance deep space transponder • Highly efficient SSPA (solid state power amplifier) • Other bus component (especially for micro-sats)

• A single mission by mother-ship and daughter-ship provided by different countries – e.g.) Mars satellite exploration with a mothership from Japan and CubeSats from other countries – e.g.) Europa/Enceladus exploration with a mothership (for remote sensing) from US and CubeSats (for multiple low-altitude flyby observation of a plume?) from other countries

• Sharing of deep space launch opportunities – Maximize the science return from limited number of deep space launch opportunities from limited countries (US, Europe, Japan, etc.) – Explore and exploit every launch opportunity over the world to maximize science return as a whole science community – e.g.) rideshare, piggyback (mothership/daughtership) “Do not miss any chance to ride!” 22 www.space.t.u-tokyo.ac.jp EQUULEUS (EQUilibriUm Lunar-Earth point 6U Spacecraft) onboard SLS EM-1 in 2018

Mission to Earth Moon Lagrange Point by University of Tokyo and JAXA Intelligent Space Systems Laboratory ISSL The University of Tokyo Summary • Univ. of Tokyo and JAXA successfully developed the world’s first 50kg-class micro-spacecraft PROCYON at very low-cost within very short time (~1year).

• PROCYON’s one-year deep space flight was quite successful. Almost all the missions were completed and we could demonstrate that micro-spacecraft can be a useful tool of deep space exploration.

• Future prospects of deep space exploration by small sats – Micro-satellite with high performance requirement – Nano-satellite which is optimized for limited mission scope

• International collaboration is essential to maximize the outcome of deep space exploration – Sharing ideas, components, sub-systems, spacecraft, launch opportunities

• We would like to contribute to extending our knowledge of the solar system.

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www.space.t.u-tokyo.ac.jp CubeSat (2003,2005) 世界最小10cmの超小型衛星バス開発

Challenging new space frontier by small satellites Intelligent Space Systems Laboratory, Univ. of Tokyo