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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.

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.

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.

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.