Lateral‐Acceleration Experience of Six Commercial Vehicles
Tire Science and Technology
This paper examines the lateral-acceleration experience of double-and triple-trailer vehicles in regular commercial service. The test fleet included seventeen tractors, eighty-six semitrailers, twenty-eight C-dollies, and sixteen A-dollies spread among five commercial trucking fleets. Data were gathered during 350,000 miles of travel over a period of eight months. Lateral acceleration signals were processed in the frequency domain to compare the rearward amplification qualities of A-trains and
... es of A-trains and C-trains. Results from this normal operating environment agree remarkably well with measurements made previously in severe maneuvers conducted at the test track or in vehicle simulations. Histograms of lateral acceleration experience are also presented. A rearward-amplification-like measure obtained in the time domain collaborates the findings in the frequency domain. Time-domain data also suggest that drivers take note of the lateral performance qualities of their vehicles and modify their driving behavior accordingly. Introduction References Content OVERVIEW OF THE FIELD STUDY Test operations of the LCV field study were conducted in the five contiguous states of Washington, Oregon, Idaho, Nevada, and Utah, which each allow the use of Rocky Mountain doubles on a designated highway system. Four of these five, excluding Washington, allow operation of triples on a somewhat more restricted network. Western doubles may operated in all states. The various types of vehicles in the field study appear in figure 1 . The test fleet consisted of seventeen "vehicles" where a vehicle is the collection of tractors, dollies, and semitrailers that service a single route within a fleet's operation. While only one tractor is required for this, extra trailers and dollies are generally needed. For example, a triple would typically service three stores and use nine trailers. At any particular time, three trailers would be at a distribution center being loaded with goods, three would be en route to the stores, and three would be at the stores being unloaded and perhaps loaded with return goods. Through variations of such scenarios, the test fleet included seventeen tractors and eighty-six semitrailers. Prior to the field test, one of the participating companies used C-dollies. UMTRI retrofitted the trailers of the other fleets with the necessary hitches and provided the required C-dollies. Twenty-eight C-dollies and sixteen of the fleets' own A-dollies were used in the study.