Pivot steering resistance torque based on tire torsion deformation

• A normalization torsion deformation model for tire/ground contact area is proposed.
• The model characterizes nonlinear torsion deformation and deformation transition.
• A prediction equation for pivot steering resistance torque of a tire is proposed.
• The resistance torque is linear and nonlinear with some factors respectively.
• The equation was validated in accuracy by experimental and simulation results.

This paper presents a normalization model to characterize the nonlinear deformation of a tire in the tire/ground contact region based on tire torsion deformation and an equation to predict the pivot steering resistance torque of the tire. The model was established based on experiments and the equation was derived using it and the principle of minimum energy consumption. The equation shows that the torque is related to parameters such as vertical load on the tire, coefficient of sliding friction, steering angle, kingpin inclination, radius of the tire/ground contact region and turning radius from the intersection point of extension line of the kingpin axis and the ground to the central plane of the tire. The equation was validated in accuracy by carrying out analyses of the measured values and predictions of the torques under seven different loads. Additionally, the applicability of the equation in engineering was evaluated by performing analyses of the measured values and simulations of the link forces of the steering mechanism for a nine-axle vehicle. The results from both of the analyses demonstrate that the equation is reasonable and has satisfactory accuracy to an extent.