Influence of lumbar support on tractor seat comfort based on body pressure distribution

Abstract

To solve the problem of lumbar spine injuries of tractor drivers, lumbar support devices were added to the tractor. The purpose of study is to design lumbar supports with different protrusion thicknesses to adjust the load on the operator’s lumbar under whole-body vibration. Integrating pressure distribution measurement with subjective assessment, pressure distribution on the contact surface between ten male tractor drivers and the seat under conditions of different lumbar supports and driving speeds and the influence of the presence of lumbar supports and their thickness on the subjects’ comfort were analyzed. The results demonstrated that there existed a certain correlation between the pressure distribution indexes and the drivers’ subjective evaluation, and the pressure distribution indexes could reflect ride comfort objectively. The 3 cm thick lumbar support did not improve ride comfort significantly, while the 9 cm thick support exerted too much stress on the waist, causing the lumbar spine to lean forward excessively and aggravating lumbar fatigue. Most subjects in the study would prefer to increase the thickness of the lumbar supports to approximately 6 cm. Based on the pressure distribution test, this study conducted an analysis of the influence of lumbar supports in tractors, which could provide a reference design for tractor seats.