Coqui-Bucket

grabcad

Literature from the current Rassor bucket demonstrates its loading and unloading mechanism's effectiveness for robotic purposes. This is why I decided to retain the basics of rotation for this new model, while changing input levels and the retaining mechanism. The new model features an internal mechanism that allows regolith input during loading by "opening a door", which offers no resistance in that direction. As soon as the scoop disengages from the soil, this "door" is drawn back to its original straight position: closing the scoop entrance and preventing regolith escape. The "door" cannot open in the opposite direction. These doors are mounted on an internal shaft held by two one-way bearings installed within the principal Rassor's shaft. During loading, the internal mechanism moves with the bucket. When unloading, the one-way bearing leaves the internal mechanism "floating", and the doors open due to the internal surfaces of the rotational bucket, clearing the scoop openings for regolith egress. The model features two diameters: a larger diameter on the sides and a smaller diameter at the center. This design limits regolith grouping in a single location. Side scoops provide an entrance for rocks up to 2.5 cm in diameter, while central scoops allow entry for rocks up to 5 cm in diameter. The maximum diameter is 450 mm, bucket length is 310 mm, and maximum volume capacity with the internal mechanism is approximately 27 liters. This results in a fill ratio of approximately 65% for the minimum 17.5 liters. Materials used include Al 5086, Polyethylene, Acrylic, and Ti-6Al-4V for the Internal Mechanism, Doors, Bucket or Shell, and Blades, respectively. The total mass is 5.5 kg, with a possibility of decreasing overall weight by modifying internal mechanism measurements. The bucket's mass alone is 2.6 kg. For design purposes, Siemens NX 12 was used, with all parts being original designs except for the one-way bearing sourced from McMaster Carr.