A Simple Differential Brake Control Algorithm for Attenuating Rearward Amplification in Doubles and Triples Combination Vehicles

Abstract

A simple brake control algorithm useful for attenuating rearward amplification tendencies in doubles and triples combination trucks is described. The basic goal was to first design, and then to demonstrate through experimental testing, an automatic brake control system that could intervene - only when needed - to help suppress unwanted trailer yaw oscillations (commonly referred to as ‘rearward amplification’) in large combination vehicles (typically doubles and triples combinations in the U.S.). The system would only be enabled for highway speed operating conditions, and if possible, so simple that the system could be provided on a trailer-by-trailer basis. That is, the proposed system, when implemented on a particular trailer within a combination vehicle train, would not have to depend upon sensor information from units ahead of it or behind it in order to function properly and yet provide significant benefit. The primary focus therefore of this work was on the development and demonstration of a so-called “trailer-only” RAMS (Rearward Amplification Suppression) system [1].