A holographic wheel/rail contact force identification model by use of vehicle accelerations
Combined with the optimal control theory, wheel rail creep theory and Kalman filtering method, this paper established a holographic wheel rail contact force identification model. The identification results were compared with the simulation results and inspection data, and the identification model was verified. Firstly, the identification problem was converted into the design issues of optimal control strategy, and an optimal acceleration state tracker is designed using the state space equation of the vehicle system. Secondly, the design issues was inversely solved using Singular Value Decomposition (SVD) technique, and predicted value of contact forces were obtained. Thirdly, the predicted value of contact forces was positively updated using Kalman Fliting method and inspection acceleration data, and identification contact forces including vertical forces and resultant transverse force of the wheelset were obtained. Finally, the left and right lateral contact force were converted into the function of the transverse wheelset displacement left/right vertical forces using the wheel/rail creep theory, so the ill-posed problem was solved and independent left/right lateral forces can be obtained. The identification results were verified by simulation and inspection results.