Sprayer Boom Motion, Part 1: Derivation of the Mathematical Model using Experimental System Identification Theory

Unwanted vertical and rolling rigid-body motions and excessive horizontal vibrations of the spray boom are one of the major causes of irregular spray deposit in the field. To investigate the effects of boom vibrations on spray liquid distribution, mathematical models of the sprayer dynamics have been derived. This paper describes the general concepts of black-box system identification and discusses its application for the identification of the dynamics of a tractor-sprayer combination. These general concepts are based on model parameter estimation from noisy measurement data. The stochastic model used throughout this paper is an errors-in-variables model in the frequency domain. The parameter estimation algorithm is based on the maximum likelihood principle.