Proper excitation for the derivation of the best related linear dynamic system to decribe sprayer boom dynamics

This paper discusses the derivation of the best related linear dynamic system approximation to a tractor-sprayer combination and a parametric model for the related linear dynamic system is identified. It will be of interest to check the degree of non-linearity in order to consider the validity of linear dynamic models. A simple method has been utilised based on the kernel idea of well-chosen periodic excitations where only some of the considered frequency components are excited. The non-excited frequency lines will be used to detect, qualify and quantify the non-linear distortions. To compare, the tractor-sprayer combination has been excited with a normal multisine and an odd-odd multisine excitation. Next, a parametric transfer function model has been identified in the frequency domain for both data records respectively. The experiment affirms that odd multisines can give positive results in the presence of non-linear distortions. Indeed, derived models even better describe the system than those models obtained from experiments with a multisine excitation.