Vibration Mitigation of Commercial Vehicle Active Tandem Axle Suspension System

A tandem axle suspension is an important system to the ride comfort and vehicle stability of and road damage experience from commercial vehicles. This article introduces an investigation into the use of a controlled active tandem axle suspension, which for the first time enables more effective control using two fuzzy logic controllers (FLC). The proposed controllers compute the actuator forces based on system outputs: displacements, velocities, and accelerations of movable parts of tandem axle suspension as inputs to the controllers, in order to achieve better ride comfort and vehicle stability and extend the lifetime of road surface than the conventional passive suspension. A mathematical model of a six-degree-of-freedom (6-DOF) tandem axle suspension system is derived and simulated using Matlab/Simulink software. Control performance criteria such as vertical body acceleration (VBA), front suspension working space (FSWS), rear suspension working space (RSWS), front dynamic tire force (FDTF), and rear dynamic tire force (RDTF) are evaluated through bump and random road excitations to quantify the effectiveness of the proposed controlled active suspension systems. The simulated results indicate that the proposed controllers can provide a significant improvement in ride comfort and vehicle stability and minimize road damage over the passive suspension. The power consumption of the proposed controllers is evaluated and compared for both the front and rear axle. Finally, the designed FLC based on velocity and acceleration offers a superior enhancement of system vibration performance among all investigated suspension systems and needs less power.