Improvement of the method of calculation of pressure of combine harvester propulsion on soil

BACKGROUND: Currently there is no simple and reliable algorithm of assessment of pressure on soil for the harvesters presented on the market. Therefore, analysis of the methods presented in active standards and used in calculation of pressure of propulsion on soil as well as development of the simplified and acceptable for manufacturing specialists method are relevant.

AIMS: Simplification of assessment of force action to wheels and soil during the operation cycle from the beginning and until the end of combine harvester tanker filling.

METHODS: The method of assessment of values of combine harvester wheel pressure on soil during the tanker filling operation cycle that allows exclusion of weighing of a harvester with a filled tanker is proposed.

RESULTS: As the result of studies, the complex of sequential actions of determining of load of machinery propulsion on soil, including determining of weight and center of mass coordinates for the grain inside tanker with the following determining of wheel normal forces caused by summarized load action of grain and a harvester (with an empty tanker) considering location of their centers of mass, was justified.

CONCLUSIONS: The new method application makes it possible to define maximal wheel pressure on soil with the filled tanker as well as the range of this indicator’s values from the beginning and until the end of tanker filling with grain. In this case, weighing of a harvester with a filled tanker at the special area with hard surface including the procedures of grain loading, unloading and weighing, is excluded. As a result, the ability of quick comparison of combine harvesters with the criterion of level of impact on soil in respect to tanker filling operational cycle beginning and end is ensured, which is the study subject. Thus, in order to solve the given task, it suffices to use the weighing results of harvesting machinery with an empty tanker, available in open sources, followed by calculation according to the proposed algorithm. Minimal divergence (less than 2%) of calculated and measured with use of platform scales values of maximal wheel pressure on soil is found.