On-board estimation of the rollover threshold of tractor semitrailers

This paper describes a working prototype of a (R) under bar oll (S) under bar tability (A) under bar dvisor (RSA) system for tractor-semitrailer combination vehicles. The RSA estimates the quasi-static rollover threshold of the vehicle while it is underway in normal service. This estimate is obtained within a few minutes of travel following any significant change in loading condition. The rollover threshold and the current operating level of lateral acceleration are displayed to the driver while under way and are also recorded to provide fleet managers with a resource for accessing and improving the overall rollover risk of their fleet. A three-year field test to evaluate the effectiveness of a second generation of RSA in actual commercial service is planned.