Design of tire pressure monitoring system based on resonance frequency method

The tire pressure monitoring system (TPMS) which is mainly used to monitor in real-time the tire pressure during driving is an effective measure instrument for guaranteeing safe driving. TPMS has crucial significance for improving the safety of vehicles, thus will gain wide applications in future. A new wheel-speed based (WSB) TPMS is designed; the principle and the hardware frame of the system are described. To solve the key techniques of estimating the resonance frequency of the torque vibration, two methods of resonance frequency estimation, one based on adaptive weights preconditioned conjugate gradient (AWPCG) and the other based on non-uniform sampling wavelet transform (NUSWT), are presented. The results show that both AWPCG algorithm and NUSWT algorithm can be efficiently used in the calculation of the resonance frequency of the wheel velocity signals in TPMS. The resolution of AWPCG algorithm is higher than that of NUSWT algorithm, while the latter saves time and resources.