Weigh-in-Motion System Design with Piezoelectric Sensor

WJM (Weigh-In-Motion) system is an important part in the traffic data collection and law enforcement. A WIM system based on multiple piezoelectric sensors has been built to acquire data of axle weight from a moving vehicle. In order to design a good WIM system, different kinds of WIM systems will be compared in this article. Algorithms have been developed to interpret the acquired data and compute the axle weight, then to estimate the gross weight of the vehicle. A model of piezoelectric sensor was used to simulate the performance for WIM system that was also applied for the design of the charge amplifier. Comparison between Peak and Area Integral Algorithms has been made. The new speed correction algorithm conducts the measurement more accurately. The multiple sensors based design improves the measurement accuracy by reducing the effect of the vehicle dynamics.