ARS | Publication request: Test of pressure transducer for measuring cotton-mass flow

Submitted to: Journal of Cotton Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 1, 2011
Publication Date: July 5, 2011
Citation: Mailander, M.P., Moriasi, D.N. 2011. Test of pressure transducer for measuring cotton-mass flow. Journal of Cotton Science. 15:1-7.

Interpretive Summary: When the local environment is closely monitored and only the necessary crop inputs are applied in each portion of the field, yields could be optimized to maximize net returns and reduce adverse environmental impacts of the production system. The first stage in this process, which is known as site specific crop management or precision agriculture, is site specific crop yield information determined by crop yield monitors. The objective of this study was to develop and test a cotton harvester yield monitor based on pressure. A cotton harvester yield monitor was developed based on the relationship between air pressure and the mass of seed cotton conveyed. The sensor theory was verified by laboratory tests. The sensor was tested on a cotton picker with seed cotton at two moisture contents, 5.9% and 8.5% wet basis (w.b.). A sensor error of less than13% was achieved for seed cotton sample at a moisture content of 8.5% w.b. and less than 48% for seed cotton at a moisture content of 5.9% w.b. The sensor was non-intrusive to the flow of seed cotton along the conveying duct. Although the accuracy of the sensor at a moisture content of 5.9% w.b. was poor, it is uncommon for seed cotton to be harvested at moisture content below 6% w.b.

Technical Abstract: In this study, a cotton harvester yield monitor was developed based on the relationship between air pressure and the mass of seed cotton conveyed. The sensor theory was verified by laboratory tests. The sensor was tested on a cotton picker with seed cotton at two moisture contents, 5.9% and 8.5% wet basis (w.b.). Regression analysis on the means of the data signals resulted in a coefficient of determination of 0.43 for the lower moisture content and 0.84 for the higher. Frequency and moving average filters were applied to the signals but did not improve the correlation appreciably. A method of compensating for gaps in the material stream resulted in an increased coefficient of determination of 0.52 and 0.87 for seed cotton at a moisture content of 5.9% and 8.5% w.b., respectively.