THREE-POINT HITCH DYNAMOMETER FOR MEASURING TRACTOR-IMPLEMENT FORCES

Determination of the traction forces between the tractor and its implement is important due to optimal utilization of tractor power and its connected implement, estimation of soil properties or strength, and fatigue studies. The working width of agriculture implements is increasing, which demands higher traction forces. The article presents the design and test in-field measurement of a double-frame dynamometer for the three-point hitch of the tractors, which can measure forces up to 400 kN. The dynamometer is equipped with six force transducers positioned so that force measurement on all axes is possible. The connection of the dynamometer follows the standard ISO 730. The design of the dynamometer and force calculations are presented. The in-field measurement was performed using disc and chisel tillage implements at different tillage depths. The increasing magnitude of the resultant traction force with increasing tillage depth and the effect of the geometry of tillage machines were found.