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The 2014 SAE Buckendale Lecture will address the past developments and challenges of electromechanical “smart” systems for improving commercial vehicles' functionality. Electromechanical systems combine traditional mechanical devices with electrical components to provide far higher degree of functionality and adaptability for improved vehicle performance. The significant advances in microprocessors and their widespread use in consumer products have promoted their implementation in various classes of vehicles, resulting in “smart” devices that can sense their operating environment and command an appropriate action for improved handling, stability, and comfort. The chassis and suspension application of electromechanical devices mostly relate to controllable suspensions and vehicle dynamic management systems, such as Electronic Stability Control.

The main intent of this study is to provide a simulation analysis of rollover dynamics of multi-trailer commercial vehicles in roundabouts. The results are compared with conventional tractor-semitrailer with a single 53-ft trailer for roundabouts that are of typical configuration to those in the U.S. cities. The multi-trailer commercial vehicles that are considered in this study are the A-double trucks commonly operated in the U.S. roads with the trailer length of 28 ft, 33 ft, and 40 ft. The multi-body dynamic models for analyzing the rollover characteristics of the trucks in roundabouts are established in TruckSim®. The models are intended to be used to assess the maximum rollover indexes of each trailer combination subjected to various circulating speeds for two types of roundabouts, 140-ft single-lane and 180-ft double-lane.

The objective of this paper is to describe a Class 8 heavy truck that the Virginia Tech Center for Transportation Research has modified and instrumented for use in evaluating Intelligent Transportation Systems (ITS) technologies. The truck is capable of recording a variety of data, both electronic and video, in real-time from a suite of sensors and cameras that have been inconspicuously mounted on the tractor. The tractor, trailer, and instrumentation package enable Virginia Tech to conduct commercial vehicle ITS research related to safety and human factors, and advanced vehicle control systems (AVCS). This paper will describe the instrumentation package, and address both general and specific types of research that can be performed using this truck.

This paper studies the effect of different longitudinal load conditions, roundabout cross-sectional geometry, and different semi-truck pneumatic suspension systems on roll stability in roundabouts, which have become more and more popular in urban settings. Roundabouts are commonly designed in their size and form to accommodate articulated heavy vehicles (AHVs) by evaluating such affects as off-tracking. However, the effect of the roadway geometry in roundabouts on the roll dynamics of semi-tractors and trailers are equally important, along with their entry and exit configuration. , Because the effect of the roundabout on the dynamics of trucks is further removed from the immediate issues considered by roadway planner, at times they are not given as much consideration as other roadway design factors.

This paper provides a simulation analysis of a novel interconnected roll stability control (RSC) system for improving the roll stability of semitrucks with double trailers. Different from conventional RSC systems where each trailer’s RSC module operates independently, the studied interconnected RSC system allows the two trailers’ RSC systems to communicate with each other. As such, if one trailer’s RSC activates, the other one is also activated to assist in further scrubbing speed or intervening sooner. Simulations are performed using a multi-body vehicle dynamics model that is developed in TruckSim® and coupled with the RSC model established in Simulink®. The dynamic model is validated using track test data. The simulation results for a ramp steer maneuver (RSM) and sine-with-dwell (SWD) maneuver indicate that the proposed RSC system reduces lateral acceleration and rollover index for both trailers, decreasing the likelihood of wheel tip-up and vehicle rollover.

This paper presents the results of a study on the effect of truck configurations on the roll stability of commercial trucks in roundabouts that are commonly used in urban settings with increasing frequency. The special geometric layout of roundabouts can increase the risk of rollover in high-CG vehicles, even at low speeds. Relatively few in-depth studies have been conducted on rollover stability of commercial trucks in roundabouts. This study uses a commercially available software, TruckSim®, to perform simulations on four truck configurations, including a single-unit truck, a WB-67 semi-truck, the combination of a tractor with double 28-ft trailers, and the combination of a tractor with double 40-ft trailers. A single-lane and multilane roundabout are modeled, both with a truck apron. Three travel movements through the roundabouts are considered, including right turn, through-movement, and left turn.