A New Predictive Lateral Load Transfer Ratio for Rollover Prevention Systems

In rollover prevention systems, a real-time lateral load transfer ratio (LTR) is typically computed to predict the likelihood of a vehicle to rollover and, hence, initiate rollover prevention measures. A traditional LTR largely relies on a lateral accelerometer signal to calculate rollover propensity. A new predictive LTR (PLTR) is developed in this paper, which utilizes a driver's steering input and several other sensor signals available from the vehicle's electronic stability control system. The new PLTR index can provide a time-advanced measure of rollover propensity and, therefore, offers significant benefits for closed-loop rollover prevention. Simulation results are presented using the industry-standard software CarSim to demonstrate the benefits of the new PLTR index. Experimental results of open-loop comparisons between LTR and PLTR indexes are presented, followed by experimental results on the closed-loop implementation of a PLTR-based rollover prevention system. The results in this paper document how a predictive rollover index can be developed and the advantages of such a system in rollover prevention.