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As part of improving road safety around trucks, a solution was proposed to reduce the swept path width of a moving tractor–semi-trailer. This article presents a mathematical analysis of the movement of a tractor unit with a traditional semi-trailer with fixed axles and steered wheels. A simulation analysis of both presented vehicles was carried out. The core of the algorithm controlling the steering angle of the semi-trailer wheels is presented. The influence of controlling the semi-trailer’s swivel wheels on the swept path width of a tractor–trailer with a semi-trailer equipped with swivel wheels is discussed. The assumptions for building the control algorithm are presented. The article presents the advantages of the solution used along with the control algorithm. Measurable benefits resulting from the use of the presented solution are presented, such as increasing cargo space, reducing cargo transport costs, and reducing aerodynamic resistance and fuel consumption. It is worth emphasizing that reducing fuel consumption is very important because it reduces the emission of harmful exhaust gases into the atmosphere. The swept path width is important especially in the case of vehicles moving in a limited area, for example in the parking lots of transhipment and logistics centers, between urban buildings. Vehicles admitted to traffic meet the minimum conditions imposed by homologation regulations, but reducing the swept path width allows for improving the operational properties of the tractor–semi-trailer. The use of the proposed control algorithm to control the turn of the semi-trailer’s steered wheels brings tangible benefits both in improving road safety and in reducing the emission of harmful substances into the environment.

The presence of a bogie in three-axle vehicles when moving along a curved trajectory leads to deterioration in its handling and maneuverability. The paper developed a mathematical model of the elastic bogie wheel while moving along a curvilinear trajectory, according to which the bogie wheel simultaneously participates in curvilinear and plane-parallel motion with a slip angle. Such movement of the bogie wheels develops significant lateral and longitudinal forces on the steered wheels, which leads to the movement of the steered wheels with slip, redistribution of the load on them, tire twisting, and a decrease in the steering angle of the outside steered wheel due to the elasticity of the steering trapezoid. Based on the mathematical model of the bogie wheel, an analytical dependence was obtained to determine the minimum turning radius of a three-axle vehicle. The reliability of the analytical dependencies characterizing the movement of the bogie wheel along a curvilinear trajectory was determined by comparing the minimum turning radii of a three-axle vehicle with the intermediate axle lowered and raised. It has been established that the minimum turning radius of a vehicle with a bogie increases compared to a two-axle vehicle and depends on the cornering stiffnesses of the tires of the bogie and steered wheels, the bogie and vehicle wheelbases, the kinematic and elastic parameters of the steering trapezoid, the direction of turning of the steered wheels, and the load on the steered and the bogie wheels.

In this work, an analytical method for finding the equilibrium configuration of the suspension systems used for the non-steered (usually rear) wheels of the passenger car is proposed. This study is based on the static model, which takes into account the elastic elements of the suspension (springs, bushings, anti-roll bar, buffers). The external loading of the suspension system comes from the contact forces between the wheels and the ground, depending on the specific operating regime of the vehicle (static or dynamic, by case). An algorithm for analysis of the relative movements in the wheel guiding mechanisms was developed (and further integrated in the general method for finding the equilibrium position) with the purpose of establishing the deformations of the elastic elements. Finally, a computer program was conceived and tested on a particular application.

This paper presents the results of the study of the kinematics and dynamics of an elastic steered wheel depending on its state, the kingpin unit design parameters, and the tire characteristics in order to obtain dependencies for calculating the tire steering resistance torque in static state and during movement. It was established that when steering in static state, the locked steered wheel is taken as a complex mechanism, and the tire contact patch is rotated about the kingpin axis–support surface intersection point. When turning the unlocked steered wheel, it was determined that the tire contact patch participates in transport and relative motions. The transport motion center is the projection onto the support surface of the center of rotation of the wheel about the kingpin axis. The relative motion center is within the contact patch and is determined experimentally. For both states of the steered wheel, analytical dependencies were obtained for determining the tire steering resistance torque. The results of the analytical studies were experimentally verified on a bench equipped by components and aggregates of a truck, and included an additional rigid false wheel and a special rim. The false wheel made it possible to experimentally determine the tire contact patch transport motion center, and the special rim—to change the knuckle length in the range of 0.22–0.82 m.

Improving the performance of articulated vehicles is not only by completing the tractor systems, but also by intellectualizing the trailer links (TL), is a complex task. In this regard, the search for and justification of the implementation of controlled TL systems is an important process (Intelligent Trailer). The research has been carried for the purpose of development of the systemic approach from the idea schematization to the practical recommendations. The paper proposes a general approach for creating a comprehensive calculation model that establishes a link between the dynamics of movement of articulated vehicle and the active controlling systems of the semitrailer. The key moments is the developed mathematical model based on matrix technique that facilitates the creation of the universal simulation model in the Simulink environment. The created method with recommended programming product afforded to increase the exactness of modelling of curving way of articulated vehicle on 10 % under the diminishing of time on the calculation about 50 % in comparison with classical method. At the expense of experimental investigation there was confirmed appropriateness of proposed imitation model of movement dynamics of articulated vehicle, general relative mistake in comparison with theoretical investigations was not over than 5%. Additional combining to semitrailer chassis the active turning control system diminishes the size line of constant movement of articulated vehicle in the circle on 14,5% in comparison with semitrailer without this system, which is also positive from the point of safety of articulated vehicle maneuverability.

The effect of relative motion of cushion system on dynamic pressure force of steered wheeled vehicles with non-linear elastic characteristics of suspension was evaluated in the article under consideration. The problem is to find the dynamic force of system cushion-non-cushion part pressure on front wheel. The dependence for the limiting value of dynamic turning angle of steered wheels on longitudinal-and- angular oscillations amplitude and parameters describing elastic characteristics of elastic suspension was obtained. It was demonstrated that for more rigid suspensions the value of dynamic turning angle is smaller at small amplitudes of longitudinal-and-angular oscillations and bigger at big amplitudes of longitudinal-and-angular oscillations.

This paper deals with the synthesis and implementation of a controller for asymptotic tracking of the desired trajectory of a mobile robot. The mobile robot used for the experimental validation has eight motors with an inner control loop. Four steering actuators are controlled using position controllers and four driving actuators are controlled using velocity controllers. A complex robot kinematic model is converted into a control-oriented linear time-varying system, which is then used to design a time-varying control law that minimizes the quadratic optimality criterion. In contrast to conventional methodologies for solving the corresponding Riccati differential equations, a computational approach that explicitly determines the time-varying controller matrix by employing recurrent matrix computations is proposed. Mobile robot control inputs (linear velocity, steering angles and steering velocities) are forwarded to the steering and driving actuators with properly tuned position and velocity controllers using an inverse kinematic model of the mobile robot. The obtained control law is evaluated on an experimental set-up of a real mobile robot system. The controller is implemented using the Robot Operating System.

This paper concerns the use of a prototype measuring instrument for conducting measurements of the linear and angular displacements of a steered wheel in relation to the car body. The theoretical principles of the measurement are presented, as are the notation method and a solution to the system of equations of the geometric constraints of the instrument’s mechanism. In the research section, the manner in which the measurements were conducted is discussed and sample results are described. A preliminary analysis of the results is performed in the summary section.

This paper concerns the determination of the initial configuration of a mechanism of a prototypical instrument for measuring the translation and rotation of a steered wheel. It covers the determination of coordinates of characteristic points of the mechanism. They were measured using a ROMER measuring arm. In the paper the methodology of measurements is discussed, and in addition the results obtained are presented and their analysis conducted.

Skid-steered wheeled vehicles are commonly adopted in outdoor environments with the benefits of mobility and flexible structure. However, different from Ackerman turning vehicles, skid-steered vehicles do not possess geometric constraint but only dynamic constraint when steered, which leads to motion control and state estimation problems for skid-steered vehicles. The controlling accuracy of a skid-steered vehicle depends largely on feedback state information from sensors and an observer. In this study, a 3-DOF dynamic model using a Brush nonlinear tire model is built, first, to model a 6 × 6 skid-steered wheeled vehicle in flat ground driving conditions. Then, an observer using the unscented Kalman filter with a strong tracking algorithm and adaptive noise matrix adjustment (AN-STUKF) is established to estimate vehicle motion states based on the 3-DOF dynamic model. Finally, the experiment is carried out in three different driving conditions to verify the accuracy and stability of the proposed method. The results show that the AN-STUKF method possesses better accuracy and tracking rate than the traditional UKF, and the phenomenon of ICRs shifting forward of the skid-steered wheeled vehicle is also verified.