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The traditional hydraulic steering mode in articulated motor-driven vehicle makes the vehicle structure complex. Further more, the forces between the front and rear part of the articulated vehicle could damage the articulated joint body in the process of vehicle steering. However, skid steering mode could make the vehicle steer with the different speed of each wheel, which is flexible without hydraulic steering system. The purpose of this paper is to introduce the principle of skid steering mode in articulated motor-driven vehicle. In this paper, the theory of traditional wheeled vehicle’s skid-steering mode and hydraulic steering mode of articulated vehicle are used to establish the in-situ skid-steering kinematic and dynamic model. Based on the model, the vehicle trajectory and the dynamic relationships among the body structure of the vehicle, longitudinal forces, lateral forces of each wheel are described.

The mathematic model and co-simulation model for distributed-drive articulated heavy vehicles (DAHVs) are developed along with the techniques for its satisfactory verification. The objectives of this paper are to introduce and verify the researches about the assist-steering method for DAHVs. The theory of this proposed assist-steering method in this paper distinguishes it from the traditional direct yaw moment control (DYC) method or assist-steering methods in the previous studies. Furthermore, the co-simulation model developed by MATLAB/Simulink, ADAMS, and AMESim is more reasonable than the traditional methods with simple virtual models, which can replace the real test vehicle for the verification of proposed assist-steering method. Field tests were conducted with a 35t DAHV to verify the models with the comparison of vehicle responses.

It is an important problem that people can drive with the comfortable posture while they maintain optimum vision field. For the design of dump truck cab, the traditional design is ‘bottom-up’, which based on the H point. However, ‘Design by H-point’ can not meet the requirement of posture and vision field at the same time, people would always adjust their driving posture to achieve the needs of vision. A method of ‘design by eye-point’ was proposed to satisfy comfortable seating posture and vision field, in which the eye point was taken as a reference point instead of the H point. An experiment on the dump truck cab was designed to collect sitting posture photos of 55 participants. According to these statistical data, the optimum eye point can be located, and the distribution types of human joint points were given. The mathematical expressions were derived to describe the relationships between human joint points and eye point.

The articulated dump truck with independent suspensions is driven by six AC motors and each wheel is driven by one motor. Cooling system is configured in every electric wheel. The motor is the main heating source in the electric drive system. Hence, the cooling of the motor will affect the reliability and power-density of the whole electric drive system. According to the actual working conditions, the heating calculation about the cooling system has been carried out during the design process. The design concept of embedding spiral-shaped flow path in the shell of the stator has been drawn. The cooling water could pass through the path and accomplish cooling outside the stator. In this paper, the FLUENT has been used for the 3-D numerical simulation of the cooling system. The temperature field distributions of the cooling water and the shell are obtained.

This paper reports on an investigation of articulated dump trucks vibration analysis and rear suspension stiffness sensitivity analysis. Since the frame of the off-highway dump truck is integrated, the impact from the road surface against the rear wheel is transmitted to the cab directly through the hydro pneumatic suspension and the frame, and finally contributes to the ride comfort. Articulated dump trucks are different from rigid-frame off-highway dump trucks, with the frame divided into two parts and jointed by a hinge, which forms two degrees of freedom between the two parts. Compared with rigid-frame dump trucks, the impact from the road surface against the rear wheel of the articulated truck would not transmit directly to the cab through the frame for the attenuation effect of the hinge. This paper studies the truck mass centre vibration characteristic which shows the resonance frequency of the articulated dump truck.

Off-road dump truck body is exposed to abrasive wear during handling of granular materials. The wear rate of body of dump truck has direct influence on maintenance and replacement during its service process. In this paper the discrete element method (DEM) is used to simulate the granular materials of dump truck. The wear of body floor during one dumping process can be achieved by cosimulation of FEM-DEM. The wear depth variation of body has the stochastic characteristic which can be modeled by Geometric Brownian Motion (GBM). The two parameters in the stochastic differential equation, drift coefficient and diffusion coefficient, can be estimated by the wear depth measuring data. It is possible to quantitatively predict the wear evolution of every grid point of the body floor by solving this stochastic differential equation. The simulation result of the wear model is helpful to optimize design of off-road dump truck body.

Differential steering mode of distributed-drive articulated vehicle is proposed by using the characteristics of independent in-wheel motor. The compound steering system of articulated vehicle is composed of fully hydraulic steering system and differential steering. Several differential steering modes of articulated vehicle are presented, and the differential steering dynamic model of articulated vehicle is built to investigate the relationship of yaw moment and turning radius. The differential steering control strategy of articulated vehicle is studied while maintaining the vehicle in the stability domain. The energy consumption of articulated vehicle with differential steering is calculated by simulating vehicle single shift lane steering process. The simulation results show that the articulated vehicle with differential steering can reduce the energy consumption of hydraulic steering system up to 3.8%.

As construction vehicles become electrified and more intelligent, some technologies are increasingly being applied in optimal controlling vehicle dynamics and driving behavior. Manned articulated vehicles in underground mine have drawbacks such as high steering energy consumption and harsh working environment for drivers, which can be solved by above techniques. The distributed-drive articulated vehicles (DDAV) can generate the yaw moment by the reasonable allocation of each wheel driving force, which can reduce the energy consumption by assisting the hydraulic steering system in steering. In this paper, the dynamic programming (DP) is used to study the optimal torque distribution while the vehicle following the reference path with minimizing the energy consumption. Firstly, combined with the tentacle algorithm, optimal control inputs and energy consumption of the vehicle were derived from DP under each tentacle.

Intelligent autonomous articulated vehicles (IAAVs), the most important transportations of intelligent mining system, are the future direction of mining industry. Though it could realize the unmanned drive, without supports of hydraulic steering process analyses and vehicle dynamic researches, there are no references for the IAAVs to adjust the steering angle in certain driving error. It still has to check the signal from the angle sensor repeatedly to track the planned path in the working process, which lead to the low control accuracy. In this paper, the theories of hydraulic steering process and vehicle model will be developed for the vehicle intelligent control with the analyses of road and tire characteristics based on the principle of least resistance.

The four-screw propulsion vehicle has high traffic performance and strong maneuverability on the fluidized soft terrain. However, the interaction mechanism between the four-screw vehicle and the soft terrain is quite complicated. The driving performance of the screw vehicle on the soft terrain are not clear, and it is difficult to achieve accurate dynamic control of the four-screw vehicle. The mechanical relationship and motion mode of the four-screw propulsion vehicle-soft terrain interaction are theoretical analyzed, the force characteristics of the screw drive wheel under each motion mode of the vehicle are obtained. The interaction model between soft terrain of tailings dam and four-screw vehicle is established by using smooth particle hydrodynamics (SPH) and finite element method (FEM).

Autonomous truck with modular chassis has the characteristics of high driving flexibility and strong load capacity. It can be equipped with different numbers of modular chassis according to the task requirements. The application of autonomous truck can solve the problems of traffic accidents and shortage of drivers effectively, which is the development trend of trucks in the future. For the collision-free trajectory planning problem of dual-modular chassis autonomous truck, this paper designs a hierarchical local trajectory planner that combines the artificial potential field method with polynomial curve fitting method. This planner plans the center of mass trajectory firstly, and then generates the modular chassis trajectories according to the position relationship between the center of mass and the chassis.

With high maneuverability and heavy-duty load capacity, articulated steer vehicles (ASV) are widely used in construction, forestry and mining sectors. However, the steering process of ASV is much different from wheeled steer vehicles and tractor-trailer vehicles. Unsuitable steering control in path following could easily give rise to the “snaking” behaviour, which greatly reduces the safety and stability of ASV. In order to achieve precise control for ASV, a novel path tracking control method is proposed by virtual terrain field (VTF) method. A virtual U-shaped terrain field is assumed to exist along the reference path. The virtual terrain altitude depends on the lateral error, heading error, preview distance and road curvature. If the vehicle deviates from the reference line, it will be pulled back to the lowest position under the influence of additional lateral tire forces which are caused by the virtual banked road.

The large power mining dump truck usually has electric drive system for the harsh operating conditions of mining. The traction motor and multi-stage reducer are assembled in the limited space of the two rear wheels. The permanent magnet motor is often used as traction motor for its much advantage characteristic. However, the permanent magnet is particularly sensitive to the high temperatures since it can loose a part of magnetization when it is exposed to a high temperature. It is necessary to have better cooling system for improvement thermal performance of permanent magnet (PM) motor. The heat losses generated by permanent magnet motor in the off-road electric driving truck are cooled by the water to maintain the motor working effectively. This paper is focus on analyzing the thermal behavior of the PM motor numerically and experimentally.

This study focuses on the operation of trolley-assisted mining truck, which leverage overhead lines for uphill propulsion, substantially reducing fuel consumption and carbon emissions. The pantograph mounted at the truck body's front exhibits complex vibrational behavior due to the subgrade stiffness and the nonlinearities of the hydro-pneumatic suspension. Vertical dynamic model of the mining truck is constructed which considering the road conditions and suspension characteristics to illustrate the pantograph's contact force. The vibration characteristic of pantograph base is analyzed which using the spatial transformation relationship between the truck's center mass of gravity and the base of pantograph. The stiffness of pantograph is designed based on a pantograph-catenary system model considering different road conditions. The real mining truck is modeled in the Trucksim software to obtain the vibration of pantograph base.