Sampling Methods for Asteroid and Planetary Missions

P. Magnani E. Re

Marco Polo Workshop - Cannes June 2008

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Brief overview on sampling techniques

Type of missions

Example of sampling systems

Table of contents:

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Brief overview on Sampling Techniques

Sampling Techniques1) Trowel or scoop with/without projectile

Viking - Courtesy NASA Phoenix - Courtesy NASA By Galileo Avionica

SSADT (GalileoAvionica prime)

2) Trowel or scoop on a shaft/telescope rod

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Brief overview on Sampling Techniques (cont.)

3) Pneumatic - Deimos approach

5) Spiral collector (examples)

Rotating blades approach-Courtesy of Astrium

4) Particle catcher – Hayabusa pproach

Direction rotation

Cylinder axis

Ramps (only two shown)

Sample containmentinsidecylinder

Direction rotation

Cylinder axis

Ramps (only two shown)

Sample containmentinsidecylinder

Surface collection tool (CNSR)Courtesy of Selex Galileo

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Brief overview on Sampling Techniques (cont.)

7) Deployable stcky film

Courtesy of Astrium

6) Rotating corer

Corer 17 mm diameter (DeeDri program)Galileo Avionica

8) Sticky pads

Example of sticky pad by JHU-APLAerogel can be used as sticky support on a pad

(for high impact speed cases)

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Brief overview on Sampling Techniques (cont.)

9) Penetrator Harpoon System

Penetrator PrototypeCourtesy of University of Arizona

Penetrator with counter balancing masswith sabot launch(Galileo Avionica)

Courtesy of Lockeed Martin

10) Flywheel auger

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Overview on Sampling Techniques (cont.)

11) Moles (In situ)

Pluto mole (by DLR)Instrumented Mole System (tractor plus trailed moles)

(by DLR and Galileo Avionica)

12) Drill (In situ ) – They can be designed for a wide variety of performances – Eamples

CNSR SAS drill – Samples D= 100mm)(by Galileo Avionica)

Rosetta SD2 drill – Samples D= 2.5 mm(by Galileo Avionica - ASI)

DeeDRi prototype drill Samples D= 10/14 mm range(by Galileo Avionica - ASI)

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Overview on Sampling Techniques (cont.)

13) Drill (In situ ) – They can be designed for a wide variety of performances – Eamples (cont.) (Galileo Avionica)

Multistroke approachPenetration depth: 2 mSample size: d=10 mm, l=20 mm

Example of collected samples in T/V conditions(from the right):- ‘red brick’ (right)- marble (ltistroke approach- regolith

Test set up for the 2 m depth testsCAD schematics First Breadboard

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Type of missions

Possible missions classification

• Landing missions:Long stay (e.g. weeks/days)Short stay (minutes/tens of seconds)

• Touch and go missions:Max few seconds stay

• Hovering and go missions:Spacecraft at a distance from the surface (meter to several tens

of meters)

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Example of sampling Systems

Example scenario: landing with short stay (tens of seconds)

Based on:

• a fast and compact low mass articulation which can touch the surface with a sampling device (spoon shaped or cylindrically shaped) to grab the intended amount of material;

• the sampling device will implement a rotation in order to favour the penetration into regolith and a shutter device to hold low cohesion material with no need of compression;

• in case the requirement to collect very hard material (even in debris) were to be pursued, the sampling device can implement a projectile launched in a barrel with sabot which prevent sample contamination;

• the sampling device can implement internally some sheets of aerogel (to favour the collection of debris).

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Example of sampling Systems (cont.)

Example scenario: landing with short stay (tens of seconds)

Articulation (3-4 d.o.f.)Stowed sample holder

(s)

Pushing plus rotationfor sample collection

Cruise and Approach Landed

Sampling Collected Sample recovery

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Example of sampling Systems (cont.)

Example scenario: landing with short stay (tens of seconds)

Tool: Roto-translation spoon

Sampling tools

• Surface and near sub-surface sampling

• Large amount of sample collected

• Depth: (e.g. 50 – 100 mm)• Compatibility with regolith

type soil• Sampling performed in

‘short time’ (fast advancing speed)

• Low vertical reaction force

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Example of sampling Systems (cont.)

Example scenario: landing with short stay (tens of seconds)

Main features:

Four d.o.f.

Mandrel (with slip ring)

Latch I/F

Technology (depend on upper temp. requirements)

Articulation: possible scheme

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Example of sampling Systems (cont.)

Example scenario: landing with short stay (tens of seconds)Sampling Tools: a possible scheme

Several approaches possible

Occluding mechanism can differentiate:

With curtainWith semicircular barWith semispherical curtain

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Example of sampling Systems (cont.)

Example scenario: landing with short stay (tens of seconds)Some early testing (90 seconds sampling) using DeeDri corer

DeeDri corer(d chamber 12 mm)

Some set up pictures

Collected material: regolith plus mm size pebbels

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Example of sampling Systems (cont.)

Example Scenario: Hovering and goIn case of an Hovering and go mission the spacecraft can place itself at a certain distance from the surface (presumably from meters to several tens of meters), stays there for a certain amount of time and then leave the position.

Possible Sampling System Configuration (for distant hovering):The sampling can be performed by launching a probe, (flying harpoon, with appropriate speed, capable to brake and partially enter the surface of the asteroid.A dedicated capsule, internal to the harpoon and containing some material collected during the impact, can then be retrieved by utilising different techniques (e.g. via tether, by ejection and subsequent recovery).

Alternatively, if the hovering condition could be in the order of 1 metre, a remote trowel or scoop can be considered mounted on a deployable device (e.g. boom)

Possible Sampling System Configuration (for near hovering):

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Example of sampling Systems (cont.)

Example Scenario: Landing with long stay

In case of Landing with long stay missions (plus anchoring) it is foreseen the landing and stabilisation of the spacecraft on the surface of the asteroid, similarly to the Rosetta Lander. Likely long time (e.g. hours, weeks…) is available in order to perform the sampling operations.

Possible Sampling System Configuration:

Suitably sized ‘real’ drilling system. The sample quality can be maximized. The anchored system need to provide adequate vertical thrust reaction capability to support the operations in hard materials.