Self-propelled prototype soybean harvester
A four-row self-propelled prototype of a new and simplified concept soybean harvester was built and field tested 
as part of a major project carried out for several years. The prototype threshes soybeans from standing, uncut plants using 
impact energy provided by plastic fingers mounted on opposite rotating shafts, and uses a pneumatic system for capturing, 
separating, cleaning, and transporting the beans. Compared to ten different combines from each of three brands with 
conventional tangentially fed threshing systems, and ten different combines from a brand with an axial-flow threshing system, 
the prototype-harvested seeds were significantly better with respect to broken/split beans and seed coat damage than all the 
combines with tangentially fed threshing systems. The amounts of material-other-than-grain (MOG) in the samples harvested 
with the prototype were significantly less than for all conventional brands. The seed vigor of the samples from the prototype 
was significantly better than those from one of the combine brands with a tangentially fed threshing system. Invisible 
mechanical damage, germination, and grain field losses were not statistically different between the prototype and all combine 
brands evaluated. The overall results confirmed the better quality of the collected beans, including that obtained with previous 
versions of the prototype. It also showed that the harvesting module, initially designed for small and medium-size farms, was 
adaptable to a self-propelled unit and therefore to larger-scale operations.