U.S. patent application number 15/592180 was filed with the patent office on 2017-08-31 for electromagnetic regolith excavator.
This patent application is currently assigned to DEEP SPACE INDUSTRIES INC.. The applicant listed for this patent is DEEP SPACE INDUSTRIES INC.. Invention is credited to STEPHEN DARRELL COVEY.
Application Number | 20170247856 15/592180 |
Document ID | / |
Family ID | 51934429 |
Filed Date | 2017-08-31 |
United States Patent
Application |
20170247856 |
Kind Code |
A1 |
COVEY; STEPHEN DARRELL |
August 31, 2017 |
Electromagnetic Regolith Excavator
Abstract
A system for excavation of magnetic regolith having a collection
chamber, a transport tube, a power supply, a wiring system, a
controller, and a plurality of electromagnetic coils. Embodiments
according to the invention allow for the excavator to have an
electromagnetic rod and a flexible tubing. Further embodiments of
the invention allow for excavation along vertical and horizontal
axes and for the electromagnetic coils to be energized
simultaneously.
Inventors: |
COVEY; STEPHEN DARRELL; (ST.
AUGUSTINE, FL) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
DEEP SPACE INDUSTRIES INC. |
MCLEAN |
VA |
US |
|
|
Assignee: |
DEEP SPACE INDUSTRIES INC.
MCLEAN
VA
|
Family ID: |
51934429 |
Appl. No.: |
15/592180 |
Filed: |
May 10, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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13901570 |
May 24, 2013 |
|
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15592180 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
E02F 7/10 20130101; E02F
3/88 20130101; E02F 5/00 20130101; E21C 51/00 20130101; F16L 27/11
20130101 |
International
Class: |
E02F 5/00 20060101
E02F005/00 |
Claims
1. (canceled)
2. (canceled)
3. (canceled)
4. (canceled)
5. (canceled)
6. (canceled)
7. (canceled)
8. (canceled)
9. (canceled)
10. A system comprising: an electromagnetic excavation module; and
an electromagnetic coil wiring system attached to a power
supply.
11. The system of claim 10 wherein said electromagnetic excavation
module comprises a hollow transport tube having at least one
opening and a body and a plurality of electromagnetic coils
disposed in said hollow transport tube.
12. The system of claim 10 wherein said electromagnetic excavation
module comprises a hollow transport tube having at least one
opening and a body and a plurality of electromagnetic coils
disposed on an exterior surface of said hollow transport tube.
13. The system of claim 10 wherein said electromagnetic coil wiring
system comprises: at least one activation wire attached to at least
one of the said plurality of electromagnetic coils and at least one
individual coil controller; and at least one power wire attached to
said power supply and said at least one individual coil
controller.
14. The system of claim 13, further comprising: a system manager;
and at least one controller wire attached to said system manager
and to said at least one individual coil controller.
15. The system of claim 11 wherein said body of said hollow
transport tube is flexible.
16. (canceled)
17. (canceled)
18. (canceled)
19. (canceled)
Description
[0001] This application is a continuation of U.S. patent
application Ser. No. 13/901,570 filed on May 24, 2013.
SUMMARY
[0002] The Electromagnetic Regolith Excavator (ERE) is a proposed
method of excavation (including drilling) that uses traveling waves
of magnetism to draw magnetic materials into and through a tube and
then to direct their movement into a collection bag. It takes
advantage of the magnetic nature of most chondrite asteroids
(whether in nickel-iron grains or in ferromagnetic minerals such as
magnetite) to rapidly move large volumes of material. Non-magnetic
materials are carried along with the magnetic portion, thanks to
collisions, friction, inertia, and the careful timing of magnetic
pulses.
[0003] The ERE behaves much like a vacuum cleaner: the open end
attracts loose material, which then enters a duct and is moved
along it by directional forces until it is deposited into a
receptacle. A vacuum cleaner uses air pressure to draw in and move
material, while the ERE uses magnetic attraction to draw in and
direct the material. A vacuum cleaner depends upon friction between
air and dirt, while the ERE depends upon friction between magnetic
particles and non-magnetic ones in the existing regolith.
[0004] Near Earth asteroids (NEAs) are key resources for the
cost-effective exploration and settlement of space. However, the
microgravity environment results in several challenges for asteroid
exploitation, including the difficulty of processes such as
digging-that we take for granted on the Earth's surface. Most large
asteroids are likely rubble piles, very loosely held due to their
low self-gravity. Collisions and impacts of small bodies tend to
fragment aggregates into smaller and smaller particles, often
resulting in a fine-grained outer covering called regolith. To
excavate a bucket of regolith, a down force must be applied to push
the blade of a bucket into the regolith--and that down force
generates a Normal Reaction force which thrusts the excavator
upward, away from the asteroid. The same thing happens when
drilling is attempted. In order to begin drilling, the drill head
is pressed into the regolith, an action that immediately results in
the drilling machine pushing away from the asteroid. Obvious
solutions -attaching the spacecraft in some way to the asteroid are
cumbersome if the spacecraft must be able to traverse the
asteroid's surface gathering material.
[0005] The Electromagnetic Regolith Excavator (ERE) is a proposed
method of excavation (including drilling) that circumvents these
problems. The ERE uses traveling waves of magnetism to draw
magnetic materials interspersed in the asteroid regolith and then
to direct their movement. It takes advantage of the magnetic nature
of most chondrite asteroids (whether in nickel-iron grains or in
ferromagnetic minerals such as magnetite) to rapidly move large
volumes of material. Non-magnetic materials are entrained or
carried along with the magnetic portion, thanks to collisions,
friction, inertia, and the careful timing of magnetic pulses.
[0006] The electromagnetic mouth and throat of the ERE accelerate
ferrous grains in the surface material toward a collector in the
spacecraft. Ferromagnetic soil particles are expected to be mingled
with nonferrous particles in many asteroids' overall regolith
matrix, similar to the mix found in ordinary chondrite meteorites.
Because there is negligible gravity, the collision forces of
ferrous grains hitting other constituents is sufficient to entrain
a significant fraction of the nonferrous grains.
[0007] The ERE may be viewed as a very-low-velocity coilgun.
However, the extremely low velocities required (less than 1.0 meter
per second on an asteroid) should ameliorate the known issues with
coilgun designs.
[0008] The ERE may also function as a regolith drill, or `mole`,
since by leaving it in one place it would excavate the material at
that spot and could then be continuously lowered to remove still
deeper material.
[0009] The forces and pathways can be tuned to keep all particles
together, or to sort them into distinct streams of ferrous and
nonferrous material.
[0010] Note that a regolith-recovery spacecraft may be equipped
with several EREs, and at any one time, all but one unit may be
acting as anchors or feet and one as an excavator/drill. After a
time the duty cycle may shift to a different unit.
BACKGROUND
[0011] The excavation of asteroidal regolith is totally untried
technology, and there is no `current art`. It is, however, widely
recognized that any mechanical excavation operation will develop a
Normal Reaction Force which will tend to drive the excavation
machine away from the surface being excavated, and that anchoring
against this Normal Reaction Force is widely recognized to be
presently unsolved.
[0012] The ERE uses and relies on the unusual fact that a
significant fraction of the mass making up the regolith of both S
class and C class asteroids is likely to be magnetic or
magnetizable (ferromagnetic). It also uses the concept that this
magnetic property will allow regolith particles to become mobilized
by an appropriately pulsed magnetic traveling wave, and that
furthermore this may entrain commingled non-magnetic regolith
particles. The attraction of the magnetic fields to the regolith
and the net reaction to the movement of that regolith results in a
downward Normal Reaction Force which allows the invention to remain
in place during operation, without requiring additional anchoring
or thrusting.
[0013] A downstream add-on may use a principle similar to that of
cross-belt magnetic separators, as used in the mineral sands
industry, to separate magnetic and non-magnetic materials.
[0014] While the principle application of this invention is the
excavation and movement of asteroid regolith, by suitable
modifications of the invention it may also be used as a drill or as
an anchor.
[0015] The ERE is, in fact, an electromagnetic anchor, excavator,
drill, and separator, depending on `tunable` details of its design
and operation.
[0016] The Electromagnetic Regolith Excavator enables robotic and
crewed spacecraft to safely collect surface material from asteroid
targets that may be tumbling; because no hard connection is ever
established (unless the ERE is intentionally used as a drill or
anchor), no strong hazardous forces can be imparted to the
collection apparatus aboard the spacecraft.
[0017] An Electromagnetic Regolith Excavator makes sample
acquisition from asteroids and Phobos/Diemos more practical and
less hazardous than with harpoon-style hard connection approaches.
The absence of a hard connection also makes the extraction device
easily mobile; alternative digging or drilling methods require the
machine deploying the blade or drill to be anchored to provide
resistive force to the digging or drilling motions. Releasing such
anchors and then re-anchoring during a traverse will be cumbersome.
By contrast, the ERE generates an attractive force toward the
asteroid as it accelerates regolith the other direction into its
collection chamber.
[0018] The stream of regolith gathered by the ERE can be split to
deposit ferromagnetic particles into a collection chamber separate
from the rest of the mass. This provides a rich feedstock for
creating metallic parts, while the nonferromagnetic portion can be
heated to release volatiles for propellants and life support, with
the leftover rock used for radiation shielding.
[0019] State-of-the-Art for asteroid regolith excavation is
theoretical, since no robotic or crewed missions have accomplished
this feat. NASA's upcoming asteroid sampling mission, Osiris-REx,
employs a momentary contact method: the spacecraft sampler rams the
target at extremely low speed (0.1 m/s) and nitrogen squirts out to
fluidize the regolith for capture. The repeated impacts pose a risk
to the spacecraft.
[0020] By contrast, the Electromagnetic Regolith Excavator does not
expose the host spacecraft to ramming shocks. The ERE also provides
the safety of not establishing a hard connection with the asteroid,
in contrast with methods that harpoon the target from a free-flying
spacecraft. The ERE avoids the danger of entanglement if the
harpoon cannot be withdrawn, or if the tumble of the target imparts
large disturbances to the spacecraft during a nominal sampling
activity.
[0021] Additionally, the reaction to the magnetic forces drawing
material into the ERE serves to hold the ERE against the
asteroid--no other anchoring method is required.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a functional diagram of a simple implementation of
the invention: a single, simple tube with a series of independently
controlled electromagnets along its length. The callouts are:
[0023] 1. A hollow tube which holds the electromagnets and guides
the material being moved.
[0024] 2. A series of electromagnet coils which attract the
regolith when energized.
[0025] 3. The wires used to energize the individual electromagnet
coils
[0026] 4. The wires supplying current to the coil controllers
[0027] 5. The wires passing control signals enabling/disabling the
coil controllers
[0028] 6. The coil controllers which supply current to the attached
coil when selected by the computer.
[0029] 7. The power supply for the electromagnetic coils.
[0030] 8. The computer which controls the sequencing and operation
of the controllers, and thus the electromagnetic coils.
[0031] FIG. 2 shows a tube with multiple segments and a receiving
container.
[0032] 15. A fixed-angle segment connector
[0033] 16. A flexible segment connector
[0034] 17. Arrows depicting the directions of motion provided by
the flexible connector 16.
[0035] 18. A container (a tank, canister, bag, or other device) to
receive and hold the excavated regolith.
[0036] FIG. 3 shows a variant of the ERE with a flat entry plate 9
to prevent regolith from climbing the exterior of the tube 1.
[0037] FIG. 4 is a bottom view of the ERE of FIG. 3, showing a
grating 6 to prevent entry of particles large enough to clog the
tube interior 5.
[0038] FIG. 5 shows a variant of the ERE with a constricted
entrance 12 to prevent entry of particles large enough to clog the
tube 1 interior.
[0039] FIG. 6 shows the bottom view of the ERE of FIG. 5, revealing
that no grating is required since the entrance 11 of the
constricted tube 12 is significantly smaller than the diameter of
the interior of the tube.
[0040] FIG. 7 shows a variant of the ERE with a flared tube
entrance 14 and a larger gathering coil 13.
[0041] FIG. 8 is a bottom view of the ERE of FIG. 7, showing that
the flared entrance 14 must have a grating 10 to prevent large
particles from entering and clogging tube 11.
[0042] FIG. 9 shows a computerized multi-color rendering offering a
potential specific example of usage.
[0043] FIG. 10 shows a computerized multi-color rendering offering
a potential specific example of usage.
DETAILED DESCRIPTION
[0044] The Electromagnetic Regolith Excavator consists of a
transport tube 1 constructed of non-magnetic material, and various
configurations of electromagnetic coils 2 at or near the entrance
and along the tube. The tube may or may not be flexible, may or may
not be straight, and it ultimately dumps the moving material into a
collection bag or other container 18 beyond the reach of the last
magnet. The spacing of the coils, the strength of their magnetic
fields, and the timing and shape of the magnetic waves that attract
the regolith and move it along the tube are parameters to be
determined by experimentation in a microgravity environment.
[0045] The controller is a software-controlled, possibly camera
guided electric sequencer. The sequencer computer 8 individually
activates the coil controllers 6 via control wires 5 which, when
activated, apply current to the selected coil via wires 3. The coil
controllers 6 are powered via a current source power supply 7 using
wires 4.
[0046] In normal (excavating) operation, the coil nearest the
asteroid will be energized to attract the magnetic content of the
adjacent regolith, and just before the first particles reach it,
power is switched to the next coil in the path, and so on until the
material is allowed to deposit into the regolith collector (not
shown). The momentum of the particles is expected to carry the bulk
of the non-magnetic material as well. Note that exposed surface
magnetic particles may be drawn quickly during initial operation,
but subsequent waves will attract deeper particles, and these will
necessarily impart momentum to the non-magnetic material that
surrounds them.
[0047] To excavate regolith on an asteroid (or other similar body
such as the Mars moons Phobos and Deimos), a spacecraft will
maneuver one end of the invention adjacent to the regolith surface.
The sequencer will energize the coils 2 in sequence to move the
magnetic portions of the regolith, and via friction the
non-magnetic portions as well, into and through tube 1 until the
regolith is deposited into a container 18 at the opposite end.
[0048] Note that the ERE tube may consist of multiple segments (see
FIG. 2), which may be curved (not shown) or angled via a fixed
connector 15, and which may be articulated via a flexible connector
16 and a mechanism (not shown) to control the movement such that
the tube can be moved both vertically (not shown) and about and
around (directions of movement 17) the surface of the asteroid to
gather regolith from an extended area. In operation, the ERE will
behave much like a vacuum cleaner to draw and move large quantities
of material (by using magnetic fields instead of air pressure).
[0049] By moving the opening of the ERE vertically instead of
horizontally, it will function as a drill through the loose
regolith.
[0050] Once the ERE (in drill mode) has penetrated the surface
sufficiently, the coils may be simultaneously energized, which will
enable the ERE tube to function as an anchor.
[0051] The opening (entrance) to the ERE tube may be implemented as
a straight tube as in FIG. 1 and FIG. 2, or
[0052] 1. To prevent the entrance of potentially clogging
particles, it may have [0053] a. A smaller-diameter opening (FIG. 5
and FIG. 6) such that only particles small enough to freely move
through the larger tube can be admitted, or [0054] b. Covered with
a grating 10 that prevents the entrance of too-large particles as
shown in FIG. 4 and FIG. 8.
[0055] 2. To prevent the movement (and subsequent loss of
efficiency) of magnetic material up the outside of the tube, it may
be implemented as a: [0056] a. Large-diameter cone 14 (as shown in
FIG. 7 and FIG. 8) that extends beyond the normal reach of the
first magnetic coil, or [0057] b. A flat plate 9 (as shown in FIG.
3 and FIG. 4) which extends beyond the effective attraction width
of the first coil [0058] c. These larger cones or plates may have
additional, larger magnetic coil(s) 13 (as shown in FIG. 7) as the
first coil(s) to attract and thus motivate larger volumes of
material at one time.
[0059] 3. The magnetic movement of material up the outside of the
tube may, however, be advantageous when the invention is used as a
drill.
[0060] 4. Reversing the sequence of coil activation and thus
directing the particles down the outside of the tube is useful when
extracting an ERE tube used as an anchor.
[0061] While the above process describes a single clump of material
entering, moving through, and leaving the apparatus, by using
suitable minimum spacing between successive energized coils,
several clumps may be moved simultaneously, in synchronization or
not. Once moving, the regolith may move at a constant average
velocity, or may be accelerated to different velocities as
needed.
[0062] Clump control (via shaping of magnetic fields) may be used
to confine, as much as practical, the extent of the individual
clumps and/or their relative position within the tube, which may
allow for improved efficiency in mass moved per clump or per unit
of time.
[0063] Optical, mechanical, electromagnetic, or radio-frequency
(metal detector) methods may be used to sense the movement of a
clump, potentially improving the efficiency of material movement,
either by allowing higher velocities or more closely spaced
successive clumps.
* * * * *