![]() This paper supports the implementation of a braking efficiency estimator of urban vehicle on rural roads, based on analytical and numerical approach. Under comparable blast loading circumstances, the front and rear plates of the hexagonal sandwich panel showed less deformation than the square honeycomb core sandwich panel. For both square honeycomb and hexagonal honeycomb core sandwich panels, the front and rear face plate deflections were measured. The dynamic response of the sandwich constructions is determined using the ABAQUS/explicit finite element method (FEM). To administer the air-blast loads of 1, 2, and 3 kg TNT, a 10-cm stand-off distance is used from the front face. In the sandwich construction, both the front and rear plates are solid, and the core structure is of the shell type. The honeycomb sandwich panel is composed of steel that is very ductile. This study employed square and hexagonal honeycomb core structures to determine the minimal face deflection under blast conditions. The purpose of this study is to look at the shock wave resistance performance of two distinct types of honeycomb core sandwich structures in terms of face plate deflection and energy absorption when subjected to a blast load. Sandwich constructions with a honeycomb core have recently become popular for high strength and dynamic load. Given its stability properties and ease of implementation, the lumped one may be effectively employed for vehicle state estimation and control purposes. In particular, it is found that the transient evolution of the tangential forces may be approximated by a system of two coupled ordinary differential equations (ODEs), whilst the dynamics of the self-aligning moment may described by combining two systems of two coupled ODEs. ![]() Then, to cope with the general situation of time-varying slips and spins, two approximated lumped models are developed that describe the aggregate dynamics of the tyre forces and moment. The steady-state tyre characteristics resulting from the proposed approach are compared to those obtained by employing the standard formulation of the LuGre-brush tyre models and the exact brush theory for large camber angles. Closed-form solutions for the frictional state at the tyre-road interface are provided for the case of constant slip inputs, considering rectangular and elliptical contact patches. This paper presents a novel tyre model which combines the LuGre formulation with the exact brush theory recently developed by the authors, and which accounts for large camber angles and turning speeds. With the presented semi-physical modelling approach and identified rotational speed induced tyre behaviour, applications such as ABS, iTPMS or driving simulators can be enhanced. The resulting rotational speed induced behaviour of the static and effective tyre radius is approximated with sufficient accuracy by the enhanced model. Based on the results of an extensive tyre testing series, it is shown that the rotational speed induced tyre behaviour can be taken into account effectively by considering a linear dependence of the vertical tyre stiffness and a non-linear progressive one of the unloaded radius on the rotational speed. In the present study, a detailed experimental validation is conducted to verify, evaluate and validate the previously identified rotational speed induced effects and the developed enhanced modelling approach. ![]() Based on the fundamentals of the TMeasy 5 handling tyre model, an enhanced semi-physical modelling approach was developed to consider rotational speed dependent tyre stiffness and tyre radii in an effective and numerically efficient manner. ![]() ![]() Previous investigations showed that the tyre rotation has a distinct effect on the vertical tyre stiffness as well as on the three characteristic tyre radii, the unloaded, static and effective (dynamic) tyre radius. Performance, development and validation of vehicle dynamics applications such as anti-lock braking systems (ABS) or indirect tyre pressure monitoring systems (iTPMS) rely on a sufficiently accurate consideration of tyre properties such as transient dynamics and tyre kinematics. ![]()
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