Verification of yield monitor performance for on-the-go measurement of yield with an in-board electronic scale

A commercial combine equipped with a yield monitor and Global Positioning S ystem (DGPS) was constructed to include a weighing system in the clean grai n tank. The scale was able to output its current readings two times per sec ond to a data-logger The reading from the yield monitor and the scale could be matched to check the accuracy of the yield monitor summary as well as t he individual (1 s) readings. Harvest data from fields of corn and oats wer e collected using this system. Data from both the scale and yield monitor w ere analyzed to verify the accuracy of the yield monitor The scale was veri fied to be accurate by calibration. Results showed that the yield monitor h as two data processing streams; one gives the individual weights (I s inter val weights) and the other gives the summary weights (total load weights). The results showed that these two streams are slightly different. Further a nalysis was conducted to understand these differences. The results showed a n increase in the yield monitor accuracy with the harvest strip length. Dat a collected in 1997 were more accurate than data collected in 1996. It was concluded that improvement was primarily due to the updated yield monitor s ystem (ver. 6.02 CJC).