Sugarbeet yield monitoring for site-specific farming part I--laboratory tests and preliminary field tests

摘要

A site-specific sugarbeet yield monitoring system was developed and tested. Two weight-sensing systems were developed, tested, and evaluated on a laboratory test conveyor. One system used 152 mm (6 in.) idler wheels attached to load cells. The instrumented idlers replaced an existing chain supporting idler on each side of the harvester outlet conveyor. The second system replaced two existing idlers on each side of the harvester outlet conveyor with slide bars covered with UHMW plastic. A product flow rate was obtained from the combined load cell outputs and conveyor speed. Laboratory tests to predict accumulated weight showed a 2.5 percent error for the slide bar system and a 3.5 percent error for the idler wheel system. As a result, field testingwas performed exclusively with the slide bar weight-sensing system. Calibration was obtained by comparing accumulated truckload weight as indicated by the weight-sensing system to measured gross sugarbeet weight on individual trucks. Typical weight errors ranged from 2 percent to 3 percent with an average error of 2.3 percent. Site-specific yield information was derived from the sugarbeet flow, harvester speed and width, and DGPS receiver. Sugarbeet yield maps were developed as a visual management aid.