Study Of Weigh-in-Motion Method Based On Finite Element Method Of Wheel Load Detecting

Through studying and summarizing the research status of vehicle weigh-in- motion in domestic and abroad, and analyzing the production and scarcity of weigh-in-motion technique, a new weigh-in-motion method based on finite element theory of wheel load detecting is put forward in this paper.As weigh-in-motion is through detecting the pressure of tyre to ground to estimate the static load of truck, and the arithmetic is specified by the detection equipment, it is mostly affecting the system error and precision, so the most emphases and difficulty in the study of this paper is to construct a simple and reasonable detection equipment.Through Analyzing the model of movement vehicle,the theory of librating truck and the dynamic load of voiture, according to the momentum theorem and the thought of structural scattered in finite element analysis theory, this paper have proposed a wheel load detecting method of finite element analysis. In this method, pressure detecting cell is arranged according to the very matrix, and the pressure is measured respectively, and then the assumed wheel load is computed, finally the whole static vehicle load is synthesized. A wheel load sensor of finite element method with strain bridge and capacitive displacement transducer is designed for this reason. In the light of the momentum theorem we can compute the corresponding weight of the individual load. The load cell has employed the full bridge differential amplifier supplied by constant current source to restrain the nonlinear error which is caused by the change of the temperature and the unsteadiness of the current. The displacement transducer have used the amplifier circuit to overcome the nonlinear of the vary clearance capacitive sensor, so that to keep the linear relation between the output voltage and the input displacement (clearance change). Through the study of kinetics simulation experiment with Pro/Engineer software, we have concluded that the wheel load sensor of finite element analysis have favorable dynamic performance, and can satisfy the requirements of vehicle weigh-in-motion system. Weigh-in-motion system based on the wheel load detecting method of finite element analysis have much advantages such as the small construct of the weight equipment, the strong ability of over loading and the favorable dynamic performance.