Development of a hybrid vibration isolator for better ride comfort and vehicle stability

Prolonged exposure of vehicle vibrations can cause poor vehicle stability, driver tiredness, ride discomfort, impair focus, and even increase the chance of an accident. Automotive suspension systems are a common way to make a ride more comfortable, protect the rider and vehicle from the harmful effects of vibration. Along with variable damping, the stiffness variability is also another important aspects for the comfortable ride and vehicle stability. With this motivation, the present research focuses on developing a hybrid semi-active vibration isolator that combines a four-parametric visco-elastic model and the conventional Bouc-Wen model to demonstrate the variable damping and stiffness characteristics. The half-car model, including the suspension system, is modeled mathematically and simulated in MATLAB environment. Numerical simulations are conducted under circular, trapezoidal, sinusoidal, and random disturbances to test the performance of the vibration isolator. The peak value of displacement is reduced by 87.5%, 92%, 83.33% and 89.6% whereas the RMS acceleration value is decreased by 84.83%, 86%, 89.35% and 94.90% in comparison with the passive system for circular, trapezoidal, sinusoidal and random disturbances, respectively. Around 40% reduction in settling time is also observed for sinusoidal, circular and trapezoidal road profiles. The comparative results exhibit that the suggested isolator has superior performance compared to the passive system.