HALO Lunar Sampling System

Last crawled date: 1 year, 12 months ago

The HALO LSS for separating 1-2m rocks from smaller pieces and dust contain an inner rotating filtering cylinder in aluminum sheet metal, alternatively with an additional inner layer of Teflon to ensure low friction and good gliding capability. The inner filtering cylinder has small cutouts for small regolith pieces and dust, covering around 300 degrees of the cylinder surface area. The rest of the circular surface area (60 degrees) have larger cutouts for rocks of sizes <= 2cm. The HALO unit need to be attached to a rover arm, to be able to collect material from the ground surface and to be powered.

The procedure steps to collect and filter Regolith using the HALO LLS are:

1. The complete HALO-unit is placed near the ground and is tilted forward by the robot arm, so that the spoon get buried down in the ground <10cm deep.
2. The rover will drive forward in slow speed to collect material until the spoon is filled up(determined using camera on rover).
3. When the spoon is filled up, the robot arm, on which the HALO-unit is attached to, will lift up the unit and tilt back in an angle so that the regolith begins to slide down along inside the rotating filtering cylinder. The filtering process is being helped by the Eccentric rotating mass (ERM) onto a motor which create vibrations in the unit.
4. The filtering process begin, the filtering cylinder is rotated back and forth in a repeating sequence , within the 300 degrees interval, until all the fine small Regolith is filtered down to the second chamber (outer cylinder), gliding down and being collected into the container (using camera in the HALO to monitor results). The filtering process is being helped here as well by the ERM-motor.
5. The filtering cylinder then rotate to the next remaining surface area of 60 degrees-interval of big cutouts to collect the remaining rocks down to the second chamber (outer cylinder) and then gliding down into the container. It is rotated back and forth in the interval until all rocks are collected.
6. The robot arm with the HALO tilt down again and any remaining rocks larger than 2cm will fall out from the cylinder down to the ground. Now the procedure is finished and can be repeated until the container is full of deposits, consisting by layers of fine regolith and rocks, separated from each other.

Materials:
The skeletal enclosure is carbon fiber in side plates and pipes, which is strong and lightweight and can withstand extreme temperatures with minimal thermal expansion. Plastics used are PFA or PEEK, also resistant to wide range of temperatures. Custom made plastic bearings are used to keep low weight.

Specs:
Weight: 0,65kg, excl camera (requirement of 0.5kg not fully achieved, inner cylinder may be made shorter or smaller in diameter to cut weight).
Materials: Aluminum, (alt. Teflon), Carbon Fiber, Plastic PFA or PEEK
Power Usage: Max 10W
Total number of parts: 29
Motors: Step motor Nema 8 and Nema 11
Suggested Rotating Speed: 2-3RPM
Choice of camera: To be decided by NASA.

/Josef Snabb

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Calculations:
Required Torque (T) to choose motor
Maximum acquired regolith weight: m= 0,3kg
Radius on inner rotating tube: R=44,5mm = 0,0445m
T=F*R, were F=m*a, which means T=m*a*R
Gravitational acceleration on the moon, a=1,625m/s^2
And we get:
T=0,3*1,625*0,0445 = 0,0217Nm, converted to = 2,17Ncm


Required Torque due to Moment of inertia to rotate the inner tube will be so small and will be neglected. Same thing with friction loss in bearings. Approximately a maximum of 2,5Ncm will be required. Which means Step motor “Nema 8” at 1,6Ncm is too weak, therefore “Nema 11” at 6Ncm is selected.

Note #1!
My idea concept of submission is NOT any copy or inspiration of any other submission whatsoever. My creation was developed before any similar concepts from other users was submitted, Image File can be sent to prove original concept date, by looking at date in digital properties of the file.

Note #2: I realized that one dimension is incorrect for the function, i.e the space between the inner and outer cylinder, it is only 1,45cm and should be minimum 2cm so that rocks at 2cm size fits while gliding down into the container and not get stuck in between.

Best Regards
Josef Snabb