AIM Industrial Day ESTEC T.M.Ho 1, C. Lange 1, J.T. Grundmann 1, S. Ulamec 2, J. Biele 2, C. Philippe 3 & MASCOT Study Team

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1 DLR.de Chart 1 > Lecture > Author Document > Date MSC-2@AIM AIM Industrial Day ESTEC T.M.Ho 1, C. Lange 1, J.T. Grundmann 1, S. Ulamec 2, J. Biele 2, C. Philippe 3 & MASCOT Study Team 1 DLR RY, Bremen Germany 2 DLR MUSC, Köln, Germany 3 ESA ESTEC, Noordwijk, NL

2 DLR.de Chart 2 > Lecture > Author Document > Date MASCOT-2 Lander for AIM Design is based based on MASCOT ( MASCOT-1 ) Lander onboard Hayabusa 2 (JAXA) Launch: 2014 Dec 3 rd Arrival: NEA Ryugu Key Factor of MASCOT2 Design: Compact 329 mm x 297 mm x 208 mm Light weight total mass ~ kg Mobile Self-righting and Hopping capabilities Platform for a suite of 4 in-situ P/L side panel of main S/C via Support Structure Landing on Didymoon: Summer 2022

3 DLR.de Chart 3 System overview Configuration/Structure: highly integrated carbon-fibre composite structure. Aluminium electronics box for bus and instrument backend electronics Power: solar generator and secondary battery, redundant power supply from AIM spacecraft for active periods during cruise Communication: common communication link with COPINS payload via the AIM- S/C Omnidirectional link with one antenna on each side. DHS/OBC: Redundant on-board computer, serial data interface to the AIM-S/C during cruise Mechanisms: uprighting and hopping using motor/drive/excenter, separation mechanism including NEA GNC (attitude): proximity sensors plus solar sensors (baseline optical + backup) Thermal: active during cruise (heater power and control from AIM), passive on surface (MLI, coatings) MESS: physical and data interface to the main-s/c

4 DLR.de Chart 4 Configuration Overview - Assembly to AIM S/C and Size MASCOT-2 MASCOT

5 DLR.de Chart 5 Configuration Overview Accomodation of S/S and P/L Secondary Antenna LFR Mechanism Space for extra flat Battery GNC Sensors (new acomodation) Deployable Solar Panel Secondary Antenna Battery LFR Antenna Deployment Mechanism Mobilty Y Transceiver

6 DLR.de Chart 6 Mission phases from lander perspective Phase name Location Main events (from MASCOT-2 lander perspective) Pre-launch Launch pad --- LEOP Ascent trajectory, TBD --- Commissioning TBD commissioning Cruise Interplanetary Hibernation, with periodical health check (once every 6 months) Proximity Operations Separation, Descent and Landing Locked to AIM in asteroid system's orbit On secondary asteroid descent trajectory Lander performing pre-descent operations, instrument calibration if required Separation of the lander, traversing to the asteroid surface, possibly bouncing, ends with resting state Orientation and Relocation On the secondary asteroid surface Determination of location and attitude, relocation to the landing site, possibly bouncing, ends with rest at the operational landing site, correct side to soil and deployed solar arrays On-surface Operations On the secondary asteroid surface Performing science operations Disposal On the secondary asteroid surface * transition from scheduled transmissions to listening mode *unless ejected by DART impact

7 DLR.de Chart 7 Mission Operational Didymoon Orientation

8 DLR.de Chart 8 FBD Mobility GNC TCS Instruments OBC/DH Comms Power

9 DLR.de Chart 9 Mass Budget MASCOT-2 Lander CBE Mass [kg] Maturity Margin [%] Eff. Margin [kg] Mass (incl. Margin) [kg] Mobility % GNC % Data Handling % Communications % Power % Structure % Thermal % Harness % Mechanisms (NEA, PRM, Solar Array Depl) % Payload 2.25 LFR % DACC % MARA % CAM % Total Lander Allowed Mass [kg] delta [kg] MASCOT MESS MESS structure % Umbilical Connector % AIM to MESS Connector + Harness (MDM) % Push-off Assembly % Thermal Standoffs (TBC) % MARA calibration target % Total MESS MASCOT Mass [kg]

10 DLR.de Chart 10 OBDH System OBC Design is based on mature MASCOT-1 OBC: Redundant design, single failure tolerant 2 CPU boards (cold redundant) CPU 40MHz Boot SW stored in PROM RAM for data and code Spacewire interfaces 2 IO boards (warm redundant, cross strapped) GPIO, UART, ADC Mass Memory (Flash) Possible Modifications, i.e.: Increase size of MM for Long term science recording Implement step-down of CPU clocking frequency to lower power consumption Request for increase of sensors Serial data interface to S/C during cruise Simplified command interface to PCDU envisaged MARA MAG CAM uomega GNC PCDU1&2 MMC RS422 UARTs SpW SpW RS422 UARTs GNC sensors Temperature sensors CPU-M CPU-R OBC SpW IO Module M IO Module R GNC sensors Temperature sensors AVM, TSM, CSM, LPC RS422 UARTs RS422 UARTs RS422 UARTs JTAGs COM-M child COM-R child Umbilical TM/TC + Debug interfaces (MASCOT OBC test connector) MASCOT RF RF RF RF ANTENNA 1 ANTENNA 2

11 DLR.de Chart 11 Communication Subsystem: Transceiver Maximal distance between MS and DS is 10 km Redundant architecture with S-Band Transceiver, antennas, RF harness Transceiver HW TBD, waiting for ISL Characteristic Syrlinks EWC 31 IQ Wireless ESA TBD Frequency [MHz] S-Band S-band Directivity Full-duplex Semi-Duplex Modulation PCM /PM /SP-L BPSK/QPSK/8PSK/QAM 16 Data Rate 0.01 to 1 kbps w it h QPSK, 150 kbps Few kbps to 1 Mbps 1 to 3 kbps, w it h OQPSK Pow er Consumption <9.0W for 2W RF output W transmit mode W receive mode <3W (very low power mode possible) <6.5W for 1W RF output <5W for 0.5W RF output TX-Pow er 0.5 to 2W dBW Up to 1W Dimensions 90x96x51 65x65x x65x15 or Cubesat [mm 3 ] form factor 90x96x15 Mass [kg] 0.6 with diplexer

12 DLR.de Chart 12 Communication Subsystem: S-Band Antenna Patch antennas chosen as the best solution for omnidirectional coverage Main Features: Dimensions (mm) 82 x 82 x 20 mm Mass 80g Gain: Boresight 6 dbic 4 dbic on 30 0 dbic on 60-8 dbic on 90

13 DLR.de Chart 13 Power Subsystem Photovoltaics: available area is all but mothership interfaces, instrument, sensor and antenna windows MASCOT2 photovoltaic coverage concept is based on HY2 GNC PEC cell format: (20 mm)² custom-cut Azurspace 3G30A with coverglass. Cell spacing for semi-rigid covers and panel overlays. Battery: mass is defined by MASCOT2 total mass allocation within AIM ABSL 18650NL 7s2p topology 124 Wh deployable panel bottom side (-Z2) when deployed, MSC2 top side while undeployed deployable panel top side (+Z2) when deployed, hidden side while undeployed MASCOT2 top side (+Z) hidden while undeployed

14 DLR.de Chart 14 Structural Design Baseline CFRP Sandwich framework structure 1 middle wall, cold and warm compartment Aluminium E-Box to house all electronics (except instrument front-ends)

15 DLR.de Chart 15 Mobility Subsystem Doubling the system to fulfill requirements on steerability The drive (electronics and mechanics) is based on (TRL9) Modification of the electronics needed due to higher radiation requirements. New drive electronics is based on mature SPACEHAND design. Arm axis as far as possible away from the center of mass in MASCOT-2 No launch lock due to MASCOT-1 start experience (consider integration configuration of Mob-Units) Mobilty X Mobilty Y

16 DLR.de Chart 16 Mechanisms Overview Relocation/Hopping (design by DLR OP) Allocation and configuration Antenna Deployment (design by CBK,TUD, IPAG) Allocation and configuration S/S Mechanism Solar Array Deployment Types of mechanisms and available technologies Allocation and configuration Separation Mechanism Inlcuded units Operational principle and its impact by attachment to main S/C Kinetic Impact Dissipation Bean bag concept: Design, launch-lock requirements, dissipation effectiviness, Overall necessity and alternative concepts System Mechanism

17 DLR.de Chart 17 GNC Sensors: Baseline configuration OPS (optical proximity sensors) PEC (photoelectric cells) TS (thermal sensors) LEDs Determines proximity of asteroid surface by reflection of LED emitted light pulses output voltage as a function of the distance from the object solar cell based sun sensor output voltage UPEC is proportional to the cosine of the angle ϕ between the sun vector and the normal vector of the solar cell determines sun vector in BFF single-sensor per side: temperature readings of all sides are compared to determine which side is facing the asteroid two-per-side: temperature difference between two sensors with identical ε and distinctive α used to determine the Sunangle on lander side Flashing lights (redundant high power LED) at each lander face Time synchronized imaging from the orbiter Need several observations during one Didymoon day to get an idea about orientation

18 DLR.de Chart 18 > Lecture > Author Document > Date Subsystems Developments or Manufacturing to be subcontracted/procured GNC OPS System LED System OBDH System (hardware, components and software development) Ebox Communication: Transceiver & Antenna Power: Photovoltaik, Battery & PCDU Solar Array Deployment Mechanism