A Joint Unscented Kalman Filter Based Dynamic Weigh in Motion System for Railway Vehicles with Traction

Weight of a railway vehicle is a critical parameter which affects the operation of it. The conventional method to monitor the weight of a railway vehicle is based on placing several sensors to the substructure. This substructure based approach does not provide a continuous monitoring. In this study, a vehicle based method, which considers the use of velocity sensors mounted on a vehicle, is proposed for this purpose. It includes the use of a mathematical model of the vehicle and a joint unscented Kalman filter. Methodology has been tested based on the measurements obtained from a full scale wheel on roller type test rig which represents the structure of some trams produced in Czechia with independently rotating wheels. This indirect estimation method reveals that use of models along with a state and parameter filter improves the accuracy of the results. This approach allows continuous monitoring of the weight (or normal load) of a vehicle just with speed sensors. As well as continuous monitoring, this methodology does not require design and implementation of specially designed sensors that should be mounted to vehicle for same purpose.