Study on buses rollover warning based on roll angle threshold

A warning algorithm of bus rollover based on roll angle threshold is studied in this paper. The rollover danger and risk indicator is analyzed. With the integrated combination angle stiffness of suspension and tire vertical stiffness, a dual-axis roll model is established; according to the gyro installation location, the relationship between roll angle threshold and the maxi stable roll angle is given. The algorithm is improved combing the merits of angle and angular acceleration TTR algorithm, and is simulated with test data. The study shows that, the ground normal reaction forces of four tires can be analyzed with the dual-axis model, which has the same accuracy with the sing-axis model when calculating the maximum roll stability angle. The simulation results show that the algorithm improves the stability and sensitivity of early warning, and is effective to the rollover early warning.