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To reduce the fuel consumption of an intelligent four-wheel-drive (4WD) electric vehicle (EV), this paper presents a new method of speed trajectory planning. The proposed method can realize a fast real-time optimization of vehicle speed, aiming to achieve the minimum motor energy output according to the fuel consumption directly. In addition, the optimization method maintains the cruising speed within the deviation required to achieve a good control effect. First, the road slope information is considered, and then, a 4WD EV longitudinal dynamic prediction model and a fuel consumption function are established. Next, the state and control variables are chosen to establish the cost function; in this manner, the MPC optimization problem in each prediction horizon is transformed into quadratic form. Finally, the fast solving tool called GRAMPC is used to solve the MPC problem.

The integrated control system which combines the differential drive assisted steering (DDAS) and the direct yaw moment control (DYC) for the distributed drive electric vehicle (DDEV) is studied. A handling improvement algorithm for the normal cornering maneuvers is proposed based on motion tracking control. Considering the ideal assistant power character curves at different velocities, an open-loop DDAS control strategy is developed to respond the driver’s demand of steering wheel torque. The DYC strategy contains the steering angle feedforward and the yaw rate feedback. The steering angle feedforward control strategy is employed to improve yaw rate steady gain of vehicle. The maximum feedforward coefficients at different velocities are obtained from the constraint of the motor external characteristic, final feedforward coefficients are calculated according to the ideal assistant power character curve of the DDAS.

Axial loading of the head-neck complex in a head first collision is a major cause of traumatic cervical spine and spinal cord injuries. It has been suggested (McElhaney, 1989) that cervical spine fracture is not observed when the head and neck are forced into extension. To evaluate this posture as an injury risk reducing strategy and to estimate the loading imposed on the structures of each cervical segment a quasi-static analytical sagittal plane model of the cervical spine in extension and compression was developed in conjunction with an instrumented physical test model. The modelled structures included the anterior longitudinal ligament (ALL) the Longus Colli (Lco) and Longus Capitis (Lca) muscles, the anterior musculature of the neck (Ma), the intervertebral discs (IVD) and the spinous processes (Sp).