Basic Studies on Design Theories of Agricultural Wheels (Part II)

Motion Characteristics and Design Ideas for Lug Trailing Side

Abstract

In order to obtain the design theories of agricultural wheels, interactions between the wheel lug and soil were analyzed through the simulation of wheel lug motion with the equations, obtained in Part I, for locus curves of a wheel axle center and five points which compose conventional lug shapes by a lug trailing side, a lug face, a lug leading side and an undertread face.
In this paper, the lug trailing side is analyzed and reported. The interactions between the lugs and soil are expressed as (i) the two-dimensional acted area and (ii) the horizontal and vertical directions of resultant farce acting on the lug trailing side.
Through these analyses, following results are obtained.
(1) The acted area is varied by not only “travel reduction” and “lift reduction” but also the angle “δ” which decide the arrangement of the lug trailing side.
(2) The lug trailing side is mainly related to produce such external forces as motion resistance and flotation.
These results may be important factors to obtain design theories for the installing angle of the lug trailing side.