The Excavator is responsible for regolith excavation, caching, and transfer operations.
The excavation method chosen was the bucketwheel. Bucketwheel excavators have large constant material flowrates. They are the quintessential system for large commercial mining systems, which the team is attempting to model. The bucketwheel can also excavate deeper than the other proposed systems. This was made more important by the addition of relatively heavy gravel beneath the surface. A system which digs deep will remove more mass as there exists a material density gradient in the competition arena. Bucket wheels are also relatively easy to automate given that only vertical position is needed to fix the state of the wheel.
Cache / Transfer / Deposition
A conveyor system was chosen as a solution to both cache, transfer, and deposition systems. This system is implemented on both devices. The excavator uses a static conveyor belt with deployable walls to hold in more material, and the transport uses a dynamic conveyor belt which can articulate down and up to deposit material in the collection bin.
By using two conveyor belts for transfer and deposition, the docking and transfer procedure is accomplished by aligning two long lines on both devices and actuating both belts to move material. The transport conveyor can articulate down to the ground if necessary.