Modeling and active steering control of articulated vehicles with multi-axle semi-trailers

Dilberoğlu, Mecid Uğur
The main goal of this study is the design of an active trailer steering (ATS) control strategy for articulated heavy vehicles (AHV). The control strategy should be effective both at low and high forward speeds. A 5 DOF yaw/roll dynamic model of a tractor and multi-axle semi-trailer combination is developed. The nonlinear vehicle model is implemented on MATLAB® platform. A linearized version of the AHV model is used in the design of active trailer steering controller. A new control strategy, Lateral Acceleration Characteristic Following (LACF) Controller, in which the trailing unit tries to follow the lateral acceleration characteristics of the towing unit is proposed. The performance of a number of existing classical and more recent control strategies are obtained for standardized test conditions. The results from the proposed control strategy are compared with those of the existing active steering control strategies. Linear Quadratic Regulator (LQR) technique is used throughout the thesis. Simulation results obtained via MATLAB® show that the proposed control strategy is more successful than the existing strategies when evaluated on the basis of combined low and high speed performance.


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Citation Formats
M. U. Dilberoğlu, “Modeling and active steering control of articulated vehicles with multi-axle semi-trailers,” M.S. - Master of Science, Middle East Technical University, 2015.