LAUSR

Abstract. The basecutter is a key component of a sugarcane harvester, and its performance affects cane basecutting quality. This quality is an important indicator of harvester performance because good cutting quality can reduce cane loss and maintain high cane yield in the following year. However, the available basecutters of traditional harvesters have various problems, such as a high stubble damage rate and cane loss, which impede high-performance harvester development and thereby hinder mechanization of the entire sugarcane production process in China. In this study, a contra-rotating basecutter is proposed based on the support-cutting theory. The technological deficiency of available basecutters was confirmed using a laboratory-based cutting platform. A series of lab cutting tests using a quadratic regression revolution design were performed to compare the contra-rotating basecutter to a traditional basecutter with free cutting. Varying cutting qualities with different disc rotational speeds, cane stalk feed rates, disc tilt angles, and numbers of blades were also investigated. The optimal parameters obtained by regression analysis were verified with lab cutting tests and high-speed photographic analysis. Based on the results, the contra-rotating basecutter has a lower stubble damage rate than the traditional basecutter and can improve cutting quality. Additionally, the results indicated that the optimal parameters of the contra-rotating basecutter are a disc rotational speed of 550 rpm, a cane stalk feed rate of 0.5 m s-1, five blades, and a disc tilt angle of 0°. With the establishment of these optimal parameters, the stubble damage rate of the contra-rotating basecutter was 15%, which was much lower than that of the traditional basecutter (25%). Keywords: Cutting platform, Quadratic regression revolution design, Stubble damage, Support-cutting theory, Traditional basecutter with free cutting.