Regolith Excavator Bucket-Drum

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The design centers on developing an extremely reliable inner regolith deposition mechanism that guarantees the highest possible fill ratio. To gain a deeper understanding, please watch the YouTube video after reading this description (https://www.youtube.com/watch?v=UADDp8S8qq0). The drum core features a single titanium cast body fitted with 15 titanium scoops welded onto it in 5 columns and 3 rows. Each row of scoops is spaced at 120 degrees around the center. Except for the middle column of scoops, two columns of scoops approach the regolith simultaneously to ensure symmetry of forces about the conventional Z-X plane or the sagittal plane. This results in an odd number of columns of scoops with the middle column scoop being wider than the rest to ensure that a similar amount of regolith is excavated during each row of scooping while also preventing excess stress on a single scoop. The benefit of this type of symmetry in scoop arrangement ensures that the two regolith excavators do not need to be synchronized to maintain symmetry of forces at both ends, which is crucial for achieving zero horizontal net reaction force. Middle Column Scoop Opening Width: 72.5 mm. Width of every Non-Middle Column Scoop Opening: 42.5 mm. Angular Span of each Scoop: 90 degrees. Height of each Scoop Opening: 50 cm. Fill Ratio: 70%. Bucket Drum Mass: 4 Kg. The excavator drum is mounted on a rigid cast Aluminum Shaft and the motion of the drum around the shaft is enabled by using 2 W61876 sealed bearings at both ends of the drum secured by internal and external steps on the shaft and drum walls respectively. The drum walls are made of aluminum, and one wall is detachable for retrieving soil after collection. The rigid shaft has several sectored module 1 spur gear profiles centered about a nearly vertical position (12 degrees counterclockwise with the vertical for counterclockwise excavator rotation). Each Scoop has an aluminum container below it welded to itself with an aluminum revolute door whose opening is controlled by a passive moderately stiff spring. The door is normally closed due to spring action, and the door is embedded with a sectored spur gear profile of module 1. When the scoop approaches the ground, soil enters and gets stored in the container below. The volume of the container is sufficient for each individual scoop of regolith. After collecting regolith when the scoop reaches the nearly vertical position mentioned earlier, the door gears are driven about the rigid shaft's gears. This ensures that the container door opens at an ideal angle and at a nearly vertical position to minimize resistance due to previously filled regolith. After the collector passes the vertical position, the door gear loses contact with the shaft gear. The door gets closed due to spring action all ready for a fresh scooping action. This innovative collection mechanism utilizes the single drum actuation to drive trap doors below each scoop to achieve a maximum fill ratio of 70%. Images of maximum load simulation results of the scoop profile for a 100 N load are attached.