AN INVESTIGATION OF THE FEEDING CHARACTERISTICS OF THE FORWARD-FEEDING ZONE OF CHOPPER HARVESTERS: DEVELOPMENT OF A RESEARCH HARVESTER

摘要

Current models of sugar cane chopper harvesters are affected by glut/starve situations for gathering and feeding of cane. The gathering system, including the forward-feeding zone (knockdown and finned rollers and the basecutters) and the setup of feed-train rollers, are areas indicated for improved performance. Alternative concepts were developed to improve the functionality of the gathering system and feed-train elements. However, there remains a lack of understanding of the interactions occurring between the machine components and cane in the forward-feeding zone during gathering, feeding, basecutting and buttlifting. The interaction of these components with the cane needs to be fully understood to address the issues of feeding, including minimum knockdown angle for butt-first feeding, control of cane for active feeding, and minimising dirt intake. A novel approach was developed to modify an existing harvester to allow alternative forward-feeding systems to be fitted and tested under identical conditions. Modifications to the front end allowed incorporation of any forward-feeding layout by fitting a choice of specially manufactured modules. Two modules were developed, which incorporated leg and underslung basecutter configurations. Each module, when installed, allowed the harvester to be operated as a fully functional harvester. Evaluation of modules was supported by instrumentation, including high-speed cine film and data acquisition of loadings on components to characterise the flow of cane. Comparative trials under varying crop conditions benchmarked the flow of cane through the leg basecutter and underslung basecutter modules. The flexibility of the modular format enabled enhanced forward-feeding geometries to be evaluated and quantified using identical harvester extractor/chopper/extractor configurations. Importantly, the modules were fully evaluated in the field under commercial conditions. The functionality and performance of the harvester has demonstrated that the system is extremely flexible and offers a powerful research facility for evaluating the performance of harvester feeding systems worldwide.