Field Evaluation of a Combine Feedrate Sensor

This paper describes the development and preliminary field evaluation of a combine feedrate sensor. The sensor employs electrical capacitance sensing techniques in a parallel plate configuration in which one plate is located in the table (or platform) with the other being the table auger. The sensor indicates the mass flowrate (feedrate) of material conveyed by the auger to the feeder.

For comparison purposes, the combine harvester was intrumented for measurements of table auger torque and feeder displacement. Conventional bagging techniques of effluent over fixed time intervals were used to establish average feedrate.

The results show that the capacitance sensor provides an indication of feedrate and more linear performance over a wider range of feedrate than the other two sensing techniques.