Abstract
A grain flow rate sensor for a combine harvester was developed to measure the grain yield. This sensor installed at the end of a grain auger of a four-row heed-feeding combine detects the force that occurred when the grain flows into a grain tank. Indoor tests were conducted to determine the relationships between the sensor output signal and the grain flow rate using wheat and unhulled rice. The results showed that the coefficients of determination with respect to wheat and unhulled rice were 0.995 and 0.993, respectively. In addition, field tests were conducted to estimate the total grain mass harvested by the combine with the flow rate sensor. The sensor could determine the total grain mass at the coefficients of determination 0.945 and 0.986 in the case of wheat and rice.
