PARAMETERS FOR MODELING PASSIVE SUSPENSIONS OF SPRAY BARS

Abstract

ABSTRACT The uniformity and quality of spraying depend on the stability of the spray boom, defined as the suspension system between the boom and the machine chassis. This paper presents a procedure for improving the performance of passive spray bar suspensions through parameter adjustment. Two multibody dynamics models of a tractor sprayer set were developed to evaluate their suspension systems: a rigid body dynamics model (RBDM) and a finite element model (FEM) using deformable bodies. To calibrate the models in the experiment, an accelerating force was applied to the suspension, and the displacements of the shock absorber and the rubber springs were monitored. The FEM is more suitable for the evaluation of the horizontal oscillations of the bar, based on root mean square (RMS) values and a standard curve used to evaluate the stability of the bar. The horizontal stiffness of the bar significantly influences the oscillatory displacement and must be included in the simulation models. Resizing the structure can reduce the horizontal oscillations of the bar.

Keywords

• Rigid body dynamics
• finite elements
• simulation
• sprayer