Braking failure anti-rollover control and hardware-in-the-loop verification of wire-controlled heavy vehicles

Abstract

Considering the fault tolerance of EMB (Electro-Mechanical-Brake) braking failure and anti-rollover control at the same time is one of the urgent problems to be solved in the driving safety of X-by-wire vehicles. Accurate rollover index is a key part of anti-rollover control. Aiming at the problem that the traditional rollover index reflects that the unsprung mass of the vehicle is insufficiently affected by road excitation, a tripped vehicle rollover dynamic model is established based on single-wheel braking failure, and a rollover evaluation index NLTR (New Load-Transfer-Rate) suitable for braking failure is proposed. In order to improve the lateral safety of the vehicle when the line control fails, a hierarchical anti-rollover controller based on road adhesion coefficient identification, SM-ABS (Sliding-Mode-ABS) control and DBR (Differential-Braking-Redistribution) control is designed. Taking the rollover index threshold as the controller trigger condition, the controller effects under NLTR, traditional RI2 and standard LTR indicators are compared respectively. Simulation and HIL test show that the traditional index controller has failure risk under extreme conditions. The designed NLTR index controller can accurately evaluate the rollover risk of the vehicle, control the vehicle in time, and improve the vehicle stability by 68.18% under Fish-Hook condition.