Trailer System Research Articles

Twenty-Five Years of Pavement Smoothness Specifications in Georgia

The traveling public generally recognizes the smoothness of a pavement as a major indicator of quality. A newly constructed pavement can have excellent materials, mix design, compaction, and so forth, but if the public considers the ride rough, the quality is considered poor. While continually striving to improve the quality of paving materials in mix designs, the Georgia Department of Transportation (GDOT) began an effort in 1968 to attain the ability to accurately measure the smoothness of a pavement so that this indicator of quality could be measured and specified during construction. GDOT has been using response-type smoothness-measurement systems in its construction specifications for acceptance of projects since 1972 and since 1979 for both rejection and acceptance. The evolution of the pavement smoothness-measuring program in Georgia, the program operating procedures, and the current smoothness specifications are described. The long-term benefits of smoothness specification for pavement construction are also discussed, as is GDOT's effort to replace the Mays Meter trailer systems currently used with South Dakota-type, laser-based road profilers.

The multi‐steering N‐trailer system: A case study of goursat normal forms and prolongations

AbstractIn this paper, wheeled mobile robots towing trailers are used as examples of systems which can be converted into extended Goursat normal form. For some configurations of this class of systems, a prolongation of the Pfaffian system is necessary before the Goursat form can be achieved. The advantage of the Goursat form is that once the kinetic constraints are in this normal form, the point‐to‐point path planning problem can be solved in a straightforward way.

A multi-steering trailer system: Conversion into chained form using dynamic feedback

In this paper, the kinematic model of an autonomous mobile robot system consisting of a chain of steerable cars and passive trailers with axle-to-axle hitching is examined and converted into a multi-input chained form using dynamic state feedback. Some of the methods which have been proposed for steering two-input chained form systems are generalized to multi-chained systems, and then applied to two example multi-steering trailer systems.

Alternative Hand- and Machine-harvest Technologies for Cauliflower1

Abstract Cauliflower (Brassica oleracea L. Botrytis group) is a multiple-harvest crop, typically with 4 to 6 harvests. This study examines 4 alternative methods of cauliflower harvest, namely, the loader, trailer, improved trailer, and mechanical harvester systems. Relative efficiencies among the hand systems were indicated both by man-hours/ha, in which the trailer system was the lowest, and by man-hours/unit of product, in which the improved trailer system was the lowest. Due to yield differences and other factors, it was impossible to distinguish any overall low cost hand system; each system had areas of comparative advantage in either motivation of workers, delivery system, or in the offsetting of higher packing shed costs. While no machine harvesting system was in full-time operation, anticipated costs of the system indicated a significant cost advantage over the hand systems at all but low yields.

Stability of Car Trailer Systems With Special Regard to Trailer Design

A linear stability analysis is performed on the articulated vehicle to provide information on the effects that various trailer parameters and variations in tire pressure have on the inherent towing stability of the typical car-trailer combination. Although certain portions of the mathematical model and solution techniques are similar to some previous efforts, the results are generalized to include a much larger class of vehicles than previously presented. The results indicate that hitch loading, trailer length, mass and moment of inertia, and fairly small variations in the car tire pressures can influence trailer towing stability.

An Economic Evaluation of Bulk Transport Handling of Tomatoes for Processing1

Abstract Traditional methods of bulk handling mechanically harvested tomatoes in pallet bins were compared with handling in bulk trailer units. Substantially greater cost reduction resulted from the bulk trailer system; costs per ton to handle and transport mechanically harvested tomatoes in pallet bins averaged $4.59 compared to $1.86 under the bulk trailer system. Additional savings were realized from utilization of the equipment in the bulk trailer system with more than 1 mechanical harvesting unit.

An Economic Evaluation of Bulk Transport Handling of Tomatoes for Processing1

Abstract Traditional methods of bulk handling mechanically harvested tomatoes in pallet bins were compared with handling in bulk trailer units. Substantially greater cost reduction resulted from the bulk trailer system; costs per ton to handle and transport mechanically harvested tomatoes in pallet bins averaged $4.59 compared to $1.86 under the bulk trailer system. Additional savings were realized from utilization of the equipment in the bulk trailer system with more than 1 mechanical harvesting unit.