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The work presents the design of a traction electric equipment set of an electromechanical drivetrain (EMD) to be used with 300-hp-class agricultural wheeled tractors. Comparative characteristics of various drivetrain types used in agricultural tractors are presented; and the advantages of using EMDs in tractors are discussed. The EDM advantages are as follows: improved technical and economic parameters of the tractor; reduced dynamic loads on the tractor and diesel units; reduces wheel slippage; reduced fuel consumption (by up to 30%); continuous variation of speed of the tractor and aggregated implements; reduced expenses on maintenance, repair and spare parts; increased total reliability, controllability and comfort; possibility to use the tractor as a power source (optionally). Considered in combination, all these advantages clearly speak in favor of using electromechanical drivetrains.

The article presents results of comprehensive theoretical and experimental studies aimed at creation of traction-and-transport vehicles (TTVs) - trucks and tractors of the future, which meet the modern requirements for their active and environmental safety. The concept is based on the original complex mathematical model (CMM), which allows simulating various interaction schemes of all TTV systems, including those accounting for the contact (tribological) interaction of the wheel with the rolling surface. The CMM was used to study the work of all the subsystems of TTVs equipped with electric transmission, all-wheel steering and electro-hydraulic servo system of wheel turning, as well as with the wheel-springing system and the onboard information-and-control system. Besides, the CMM and its individual units were used as simulators for programming the functionality algorithms of all these subsystems and their relationships with each other.

Two characteristics of terrain mobility are essential in designing an unmanned ground vehicle (UGV): (i) the ability of a vehicle to move through terrain of a given trafficability and (ii) the obstacle performance, i.e., the ability to avoid, interact with and overcome obstacles encountered on a preset route of a vehicle. More attention has been given to the vehicle geometry including selection of the angles of approach and departure, radii of longitudinal and lateral terrain mobility, and the steering system configuration. An essential effect is exhibited by the tire properties in their interaction with the support surface; this, in turn, affects traction properties of the wheel and, thus, vehicle terrain mobility. However, the influence of power distribution between the driving wheels together with vehicle steering system on the two above-listed characteristics of terrain mobility has not been considered in depth.

In the coming half-century, the global transport industry is expected to be affected by two technological revolutions - the first will start upon admission of autonomous vehicles to public roads, while the second will finalize a complete removal of manned vehicles away from them. As a result of the above revolutionary shocks, several major changes are anticipated: the modification of whole paradigm of ground vehicles; introduction of new business models in the transport sector, as well as new vehicle ownership forms; transition to technologies of collective and cooperative management and synchronized parrying the dangerous traffic collisions.

An open-link locomotion module (OLLM) is an autonomous energy self-sufficient locomotion setup for designing ground wheeled vehicles of a given configuration that includes drive/driven and steered/non-steered wheels with individual suspension and brake systems. Off-road applications include both trucks and trailers. The paper concentrates on the module's electro-hydraulic suspension design and presents results of analytical and experimental studies of a trailer with four driven (no wheel torque applied) open-link locomotion modules. On highly non-even terrain, the suspension design provides the sprung mass with sufficient vibration protection at low level of normal oscillations, enhanced damping and stabilized angular movements. This is achieved by the introduction of two control loops: (i) a fast-acting loop to control the damping of the normal displacements; and (ii) a slow-acting control loop for varying the pressure and counter-pressure in the suspension system.