Field experimental study demonstrates high tuber exposure and low damage rates during integrated sweet potato harvesting in clay loam soil, indicating viable single-pass mechanization.
Key Points
To develop and evaluate an integrated harvester for synchronous sweet potato haulm shredding and tuber excavation to overcome the inefficiencies of two-stage harvesting.
Tested a prototype equipped with a front-mounted crushing knife roller and a rear-mounted adjustable grate-type digging shovel in clay loam soil.
Conducted an orthogonal test for haulm shredding and applied a quadratic orthogonal rotational composite design to optimize integrated harvesting operational parameters.
Knife roller speed significantly increased the rate of crushed stems and leaves, forward speed negatively impacted shredding quality, and blade-to-ridge clearance primarily influenced ridge-top stubble length.
Multi-objective optimization identified optimal parameters of a 66.6 mm blade-to-ridge clearance and a 34.0° shovel inclination, which yielded an 83.7% tuber exposure rate and a 4.3% tuber damage rate in field validation.