[5-1130-P] Other Categories (5th)

[5-1130-P-28] The Static Load Test for Tractor Attached Three-Point Hitch Type Dynamometerd

*Hyo-Geol Kim¹, Sung-Bo Shim², Yeon-Soo Kim¹, Young-Joo Kim¹, Sang-Dae Lee¹ (1. Korea Institute of Industrial Technology(Korea), 2. Gyeongsang National University(Korea))

Keywords:Static load test, Three-point hitch, Tractor dynamometer, Traction force, Six-component force

Due to the mechanization of agriculture and the aging of the countryside, the use of tractors and tractor machines is increasing. The tractor generates a force between the tractor and the implement, which depends on the soil properties and moisture content. The tractor travels and generates traction force, generates vertical force for maintains the position of the implement, and creates lateral forces by rolling and soil surfaces. It also interacts with the soil and causes moment in the same direction. These forces act as stresses on the tractor and the implement, causing fatigue damage and fatigue failure on the frames and components. Accurately measuring the force generated during tractor operation can predict vulnerable parts and residual life of the tractor and machine. In this study, we developed a three-point hitch type dynamometer that can accurately measure these forces, and formulated a formula for calculating the force with the geometry of the load cell attached to the three-point hitch type dynamometer. The developed dynamometer measures six components force with a single axis load cell combination and measures the PTO torque with a strain gage and telemetry system. In addition, a static load test was conducted to verify the validity of the dynamometer. Static load tests showed an accuracy of 97% or more over the entire range, from 98.9% in the traction force direction, 99.2% in the vertical force direction and 97.4% in the lateral force direction. The accuracy of the traction direction moment was 98.2%, the vertical direction moment was 97.3%, and the lateral direction moment was 96.8%, which is more than 96% accurate in all moment sections. Therefore, the formula used in the experiment is more than 96% accurate, and the reliability of the dynamometer is more than 96%. In future studies, we will establish and verify the improved formula considering the transportation pitch caused by the three-point hitch moving.