Submitted to: Transactions of the ASAE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 29, 2001
Publication Date: December 1, 2001
Interpretive Summary: Cotton mass flow rate is a necessary variable both for ginning machinery automatic control systems and for harvester yield monitoring and mapping systems. Researchers at the Univiersity of Tennessee in Knoxville built a prototype sensor which was tested at the USDA-ARS laboratory in Mesilla Park, NM. The device tested used beams of light to detect the presence of pneumatically conveyed weed cotton in a duct. Mathematical equations were used to relate the amount of time seed cotton blocked the light beams to the amount of cotton flowing in the duct. With accuracies better than 5 pct, this system holds commercial promise.
Technical Abstract: An optically-based system for measuring cotton flow rate was designed and tested in both field and laboratory environments. Accuracy was documented by comparing actual and predicted load weights. When field-tested on a cotton harvester, results were positive, with an average absolute error of 4.7 pct. A laboratory test was subsequently designed and conducted to gather data describing relationships between system performance and variables such as cotton flow rate, cotton moisture content, and cotton variety. The accuracy results of the laboratory test confirmed those generated in the field, with an average absolute error of 3.4 pct. Additionally, laboratory test results indicated a moderate correlation between average flow rate and absolute error. Variety also affected system performance, with an average absolute error of 2.4 pct for one variety, versus 4.9 pct for another. Moisture content had no detectable effect on accuracy in the laboratory test. The technology described herein has been patented and licensed to industry for application on mobile equipment.