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The operator enters the harvester and descends to the bottom of the pool, where she uses two external manipulators to gather the globes and place them in a central receptacle. When the harvester surfaces, the globes are retrieved through a water-tight hatch within the machine.
While the harvester is normally operated from internal controls, there is also a set of external emergency controls that can raise or lower the device, and open or close the outer hatch. The manipulators and catch-basket hatch can only be operated internally.