Experimental Research on Dynamic Characteristics of a Rolling Agricultural Tire: Measurement of Forces Acting on Tire Shaft

When agricultural machines are operated on pavements, the lug excitation force occurring on a rolling agricultural tire is primary cause of the vibration. Therefore, it is important to investigate the lug excitation force in order to clarify the vibration generation mechanism. In our previous study, it is considered that the dynamic behavior of a rolling agricultural tire is influenced by the vibration characteristics of the tire. Further, only the rigid modes among the natural modes could affect the rolling tire behavior. So, we modeled the tire as a circular rigid ring supported on an elastic foundation with contact model. This rigid ring model can be valid to investigate the lug excitation force, while it is necessary to measure forces acting on tire shaft in order to estimate the lug excitation force. In this study, the test equipment is modified to measure tire shaft forces at rolling, by improved supporting structure equipped with 6-component force transducers and the shaft force characteristics are investigated. It is confirmed that the vibration characteristics of the tire influence the shaft force characteristics.