Rail Vehicle Active Suspensions for Lateral Ride and Stability Improvement

Abstract

The potential performance benefits of simple, low power active elements in the lateral secondary, between the truck and carbody is investigated analytically by parametric studies utilizing a fifteen degree of freedom lateral dynamic model subject to alignment and cross-level inputs. It is shown that significant improvements in ride quality can be obtained at current operating speeds by using less than 3 kw per truck by sensing lateral carbody accelerations and utilizing lateral force actuators between the truck and carbody. It is also shown that in order to improve the truck critical speed and/or to improve the ride quality at very high speeds requires control of the truck kinematic mode. This can be achieved, at the expense of increased power requirements, by sensing absolute truck lateral and yaw velocities and utilizing combined lateral force actuators to exert a yaw moment on the truck. It is concluded that significant ride quality improvements can be achieved by low power, small bandwidth actuators while stabilty improvements requires increased power and larger bandwidth systems.

Performance of a rail car equipped with independently rotating wheelsets having yaw control

“…The baseline vehicle parameters used in the numerical calculation are given in Table 2 and are based on the values given in reference [6]. The optimal controller is designed for a vehicle with a constant velocity of 150 m=s.…”

A Procedure for Optimization of Truck Suspensions

“…Vehicle suspension designs for multi-degree-of-freedom railway vehicle models, using nonlinear programming formulations and analysis techniques have been reported in the literature [9,10]. However, there have been relatively few attempts to apply optimization techniques on the suspension design of tractortrailer combinations (see for example [2]).…”

“…The vehicle dynamic equation (7) and the dynamic equation (5) of the linear filter representing the road excitations can be combined with the shape filter representing human perception to vibration, equation (10). The resulting state equation takes the form:…”

Improvement of ride performance with an active suspension based on fuzzy logic control

“…From the half-car suspension system, the relationships among vertical displacements of the front sprung , rear sprung and vehicle body are expressed in Eqs. (5) to (8). Eq.…”

“…The controlled suspension system is now widely applied such as semi-active suspension [6,7], and active suspension [8,9]. Chen [6] proposed a new method on design and stability analysis of semi-active suspension fuzzy control system.…”