Design And Implementation Of Vehicle Mass Estimation Method Based On OpenXC

Vehicle mass estimation is an important parameter in automobile field.Accurate vehicle mass estimates are applied to vehicle shifting strategy and active safety control devices,which is helpful to improve the fuel economy and safety.The existing researches mainly focus on vehicle mass estimation when the vehicle is running on straight roads,without considering the influence of shifting the special condition for the estimation of vehicle mass.However,the vehicle driving condition is very complex under the realistic situation;drivers' shift behavior will interfere with the process of vehicle mass estimation and reduce the accuracy of the estimated results,so it is necessary to research vehicle mass estimation method under the special scenario.Therefore,considering shift factors in vehicle mass estimation will improve the estimation accuracy,and has important academic significance and application value.Aiming at the problem that the shift factors affect the accuracy of vehicle mass estimation,this paper start researching data preprocessing method from analyzing OpenXC vehicle running state data characteristics.On this basis,the vehicle mass estimation method considering shift factor is designed and implemented,and the method is improved according to the specific application scene with road slope.The main research contents include:(1)OpenXC vehicle running state data preprocessing method.In order to solve the problem that the sampling time is different in kinds of Open XC data,this paper proposes a new method of data preprocessing based on cubic spline interpolation with sliding time window.The method realizes the time synchronization of different kinds of data,and provides input data for the vehicle mass estimation method.Finally,the effectiveness of the method is verified by real vehicle OpenXC data.(2)Vehicle mass estimation method considering shift factor.Due to the existing vehicle mass estimation method is not suitable in the shifting conditions.The influence of the shifting behavior on the estimation process is analyzed.Then,based on the vehicle longitudinal dynamics model,a weighted least squares recursive mass estimation model with multiple forgetting factors is established.Finally,some simulation experiments are done to compare with existing methods;the experimental results show that the proposed method is better than the existing methods in the shift conditions.(3)Improvement of vehicle mass estimation method considering road slope factor.According to the vehicle mass estimation accuracy decreased by the influence of the road slope.In this paper,the mechanical efficiency estimation model of vehicle transmission system is established,and the weighted least squares recursive least squares estimation model is improved.Finally,the adaptability of the improved estimation method under different road slope conditions is verified by simulation experiments.Finally,finish the design and implementation of vehicle mass estimation system based on OpenXC data.The experimental results show that the proposed method can accurately estimate the vehicle quality under the influence of the shift and the road slope factor,and has a high accuracy of the mass estimation.