Curvilinear motion control laws for a semi-trailer caterpillar train for off-road cargo transportation

Abstract

BACKGROUND: For transport accessibility in areas with an undeveloped road network, the use of tracked trains that provide low ground pressure is a rational solution. To ensure the mobility of a semi-trailed, unmanned caterpillar train, which can be controlled remotely by a driver-operator or by an automatic unmanned driving system, traffic control laws are needed.
 AIMS: Ensuring energy efficiency in curve control of a unmanned semi-trailer tracked train for off-road freight transport.
 METHODS: The methods of simulation mathematical modelling and analytical methods based on the consideration of the quasi-stationary motion of the caterpillar train links are used to derive energy-efficient control laws and determine the mobility performance that can be achieved.
 RESULTS: Control laws are obtained for two variants of tracked trains: a tracked train with independent drive control of driving wheels and a tracked train with a differential drive scheme of a semi-trailer link. The control laws are designed to improve the energy efficiency of travel which is achieved by rational distribution of traction forces on the driving wheels of the tracked train and use of the regulator which ensures adjustment of the traction on the semi-trailer driving wheels accord-ing to the sign and magnitude of force in the fifth-wheel coupling of the tractor.
 A block diagram of a governing system of a caterpillar train and a mathematical description of its basic structural components (blocks) are given. Using the developed control laws the theoretical research of curvilinear movement by simulation mathematical modelling is carried out; the comparative analysis of the considered control laws of the semitrailer caterpillar train movement with two transmission variants is given.
 CONCLUSIONS: The application of the developed caterpillar train motion control laws will enable the vehicle to move unmanned or follow the lead vehicle along a set path with high accuracy of turning manoeuvres and, consequently, will improve the safety of freight transportation.