METHOD OF THE EXPRESS ANALYSIS OF SLIPPING ON VARIOUS OPERATING MODES OF A TRACTOR

Abstract

It is difficult to experimentally evaluate the traction and coupling properties of a tractor during its operation, so developing a method for an express analysis of slipping is an urgent practical task. According to GOST, traction properties are estimated against normalized soil backgrounds and the horizontal direction of the traction force vector, which differs significantly from production tests. To justify the methodology for estimating slipping when a machine-tractor unit operating on small-size sample plots, it is proposed to use a differential model. The methodology was tried based on the traction test results of the MTZ-80 tractor on winter wheat stubble and experimental studies of a chisel unit based on the New Holland S8000 tractor. The experiments were carried out for three levels of soil moisture: 11...13; 14...16; 17...19%. The tillage depth was 12...15; 17...20; and 22...25 cm. It has been established that the adequacy dispersions of the obtained dependences of slipping on the tractive effort coefficient for the compared options are practically homogeneous. For soils with a moisture content of 11...13%, the dispersion of adequacy is 0.117, for a moisture content of 14...16% - 0.637, for a moisture content of 17...19% - 0.827. With low soil moisture, the interaction of a wheel with the soil is more stable. The authors conclude that the method of express analysis of tractor wheel slipping when performing specific types of work, with a limited amount of experimental data, makes it possible to obtain dependences comparable in accuracy with the data of traction tests.