Research On The Roadway Test System For The Motor Vehicle Active Safety And Its Performance Evaluation Methods

The active safety roadway test system is developed for the motor vehicle equipped with active movement control systems on the chassis in the paper. It is intended to evaluate the active safety in the light of the wheel forces, the path and attitude of the un-spring mass (PAUSM), and to establish the bridge between the driving performance and the vehicle structure, control parameters, etc. Based on both the analysis of the active safe laws and regulations, and the summarization of the key factors of these active movement control system, the roadway test system is put forth, whose primary features are to synchronize the measuring of the wheel forces and PAUSM. Several key points of the test system, such as measurement methods, measurement precision, performance evaluation, etc, are studied systematically. The primary work of the paper are summarized as follows:(1) It is for the wheel forces and PAUSM that the motor vehicle roadway synchronized measurement system is put forward primarily. The details of PAUSM module, the measurement parameters and requirements of the whole system are presented, and so do the determination of the sensor types . The system employs the structure of distributed parameters acquisition and centralized data post processing, and the CAN bus-based data management model between the main card and the slave card. Several means, such as isolation of signal channel, modular design of software, interrupt manage of the on-chip devices, etc., are utilized to improve the reliability of PAUSM module. Based on the 32-bit timer of the DSP chip, the time synchronization is easy to implement, both between main card and slave card, and among the different signal channel on PAUSM model. The reliability of PAUSM model is verified through the debugging on the lab and the test on the spot.(2) The coupling between each component of the wheel force transducer (WFT), is studied systematically in terms of both the calibration method and the static decoupling methods. Based on the calibrating data, three methods are utilized to analyze the coupling rate of WFT, which are the multi-component linear regression (MLR), the least square support vector regression (LS-SVR) and the improved orthogonal least square radial basis function neural network (OLS-RBF NN). Four points are generalized through the comparative analysis, (i) the linearity exists conspicuously on each main channel; (ii) the static coupling rate of the WFT is equivalent to the foreign like-kind products; (iii) the generalization and stabilization of LS-SVR are outstanding; (iv) the stop study condition of the normative OLS-RBF algorithm is modified, and the cross-valid method is employed to determine the net expansion constant. The improved algorithm, complied with the NN generalization theory and covering the shortage of empirical parameter determination, is verified effectively by the simulation analysis.(3) The principal theory and engineering technology of measuring PAUSM are approached respectively, based on the indirect feedback and non-tight integrated model between the middle-and-low-precision inertial measurement unit (IMU) and the high precision carrier-phase– differential GPS (CP-DGPS) receiver. Firstly, the strapdown algorithm is derived in detail under the frame of vehicle roadway test. Then the 21-order linear kalman filter is designed for the combination measurement of PAUSM based on the linear error model of IMU. Under the filter frame, the scheme of fast initial alignment on the spot is studied. The improved kalman evaluation algorithm,...