Design Optimisation for the Vertical Suspension of a Crop Sprayer Boom

The dynamics of a vertical suspension for a 39 m wide boom on a John Deere crop sprayer was optimised. The optimisation was based on a mathematical model of the suspension with an existing non-linear Koni® damper characteristic. During the optimisation, several tracks, which are based on power spectral densities of measurements in different field conditions, are applied to the suspension. The objective function to be minimised is the standard deviation of the absolute boom rotation around the horizontal axis while applying the tracks. As the model is simple but accurate, computation time is small such that many different field situations can be imposed during optimisation. By playing with the distance to the rotation point of the damper and selection of the appropriate damping value, the optimum could be realised.