Yield monitoring apparatus, systems, and methods

A sensor assembly for determining yield of grain harvested by a harvesting machine during harvesting operations, the harvesting machine having a grain elevator housing within which a conveyor is driven in a direction of rotation around an upper sprocket, the conveyor having a plurality of spaced flights, whereby, as the conveyor rotates in the direction of rotation during harvesting operations, each of the plurality of spaced flights carries a grain pile upward from a lower end of the grain elevator housing to the upper sprocket, and as each of the plurality of spaced flights successively passes around the upper sprocket in the direction of rotation, the grain pile carried by each of the plurality of spaced flights is thrown in a direction of grain travel, the direction of grain travel being upward from the upper sprocket and in the direction of rotation of the of the conveyor, the sensor assembly comprising:

• a sensor housing mounted to the elevator housing above the upper sprocket;
• a sensor member displaceably supported by the sensor housing within the elevator housing above the upper sprocket and along the direction of grain travel such that each thrown grain pile flows across the sensor member from a first end toward a second end of the sensor member producing a grain force on the sensor member, the grain force causing an upward translational displacement of the sensor member, wherein the first end and the second end of the sensor member are displaced upwardly a substantially equal distance, in relation to the grain force;
• and
• a displacement sensor configured to generate a grain force signal corresponding to the upward translational displacement of the sensor member.