Simo System Identification of Transfer Function Model for Electrohydraulic Power Steering

The paper presents the identification procedure for obtaining of transfer function model of an electrohydraulic power steering systems for low speed mobile machines. The single-input, multiple-output (SIMO) system model was obtained based on experimentally measured data from a laboratory test bench steering system. Proportional spool valve position, flow rate supply and steering cylinder position output variables are measured in an open-loop identification experiment. The identified SIMO model is validated with independent data-set and reduced to 3rd order transfer functions. The resulting model will serve for further work on the synthesis of multivariable embedded controllers for the electrohydraulic power steering systems.