Variable speed elevator control system

A sugarcane harvester, comprising:

• a basecutter configured to cut sugarcane;
• a plurality of lower feed rollers and a plurality of upper feed rollers that are movable from a first position to a second position, the lower and upper feed rollers are in communication with the basecutter to receive and feed the cut sugarcane through the sugarcane harvester;
• a chopping device in communication with the plurality of lower and upper feed rollers, the chopping device configured to chop the cut sugarcane into billets;
• an elevator in communication with the chopping device, the elevator configured to transport the billets out of the sugarcane harvester at an elevator speed;
• and
• a control system for controlling the elevator speed based on a crop mass flow through the plurality of lower and upper feed rollers, the control system comprising:
• at least one crop mass flow feedback device configured to measure a distance moved by the upper feed rollers and provide a crop mass flow feedback signal indicative of the crop mass flow;
• and
• a controller in communication with the at least one crop mass flow feedback device and configured to relate the distance moved to a crop mass flow using a lookup table, the controller configured to lower the elevator speed when the crop mass flow feedback signal indicates a lower crop mass flow and raise the elevator speed when the crop mass flow feedback signal indicates a higher crop mass flow.