In recent years, the development of container transportation served as a powerful impetus for increasing the length of vehicles, especially road trains, which is due to a number of advantages regarding the transportation of large-sized freight in a container. Today, the whole range of containers is transported by two-link road trains consisting of a tractor vehicle and semi-trailer. The efficiency of such transportation can be increased by means of three-link road trains capable of transporting either three (two 20-foot and one 40- or 45-foot) or four 20-foot containers. This organization of transportation will lead to energy savings and a reduction in environmental pollution due to the reduction of vehicles. However, there is a problem with the maneuverability and stability of such vehicles. The paper developed a kinematic model of three-link road train type “B-triple” with steered axles (front or rear) of semi-trailer dolly with a dual drive control for these axles. Based on folding angles of road train links and drive control transmission ratios of the axles of semi-trailer dolly, the main indicators of road train maneuverability are determined – road train links trajectories displacement relative to the vehicle trajectory and road train overall traffic lane. It was established that when entering a turn with slight differences in folding angles of road train links, the steered axles of semi-trailer dolly turn in the direction opposite to the direction of a turn, thereby reducing the overall traffic lane. During circular motion, the overall traffic lane of road train with steered semi-trailers decreased by almost 2 m, but such road train does not meet the maneuverability requirements. The search for ways to improve the maneuverability of three-link road trains should be sought in the designs of three-link road trains.
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