A study of the influence of vehicle tyre pressure on suspension system response using a full car model

The incorrect inflation pressure in tyre affects vehicle handling, passenger comfort and braking conditions, as
well as reducing fuel efficiency and tyre life. To address this problem a numerical model has been
developed. The model has been developed with 7-DOF for a full car system. State space approach has been
adapted to analyze the system parameters using MATLAB programs. To validate the model, the
experimental work has been conducted by driving a car on the road with bumps with healthy tyres condition.
During the experiment the tyre pressure was controlled and the suspension vibration was measured. The
model has been validated fairly using an experimental data in time domain. For detail analysis, the Short-
Time Fourier Transform (STFT) method was used to obtain contents due to road excitation at the bumps.
The results show, by reducing the tyre pressure by 35%, the total vibration energy transmitted to the car is
increased by 27 %, 30.5 % and 28.2 % for reduction of tyre pressure of driver wheel, passenger wheel and
front wheels respectively. In addition, the result shows that the mathematical modelling can have a potential
for developing an on-line suspension condition monitoring tool in future.