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Electrification of the automobile propulsion system can improve the energy efficiency and reduce the environmental pollution. A novel single-mode compound split hybrid transmission with a compound planetary gear set and two brakes has been studied, which has more freedom of control to improve the system efficiency. With different activations of the two brakes, different working modes can be obtained. The kinematics and kinetics relationships of the compound planetary gear set are analyzed firstly. Then the kinematics and kinetics of the transmission in the three different operation modes are respectively presented by the numerical method and lever method. Besides, the power flow of the transmission in different modes is analyzed. It is demonstrated by analyses that the compound power-split hybrid transmission has advantages of configuration, control and energy efficiency over the mainstream products on the market.

A novel single-mode compound split hybrid transmission with a compound planetary gear set and two brakes has been studied, which has more freedom of control to increase the system efficiency. System dynamics and matching performance of the driveline including a compound planetary gear set for a single-mode hybrid electric vehicle are numerically investigated. The multi-degrees of freedom torsional vibration model for the full-hybrid vehicle driveline with the power split device is established by MATLAB/Simulink. For comparison of the natural characteristic, eigenfrequencies and mode shapes are determined with the aid of a further simplified single-track mechanical model under different operation modes. Then, numerical simulations of dynamics and kinematics of the driveline and the compound planetary gear set are carried out.

Since the vehicle AMT(Automatic Manual Transmission) has been developed to meet the requirements of high quality vehicles as well as hybrid vehicles, there are more and more tasks running on the ECU (Electronically Controlled Unit). Concerned with both function correctness and timing correctness, the scheduling of those tasks becomes important. A perfect scheduler, which distributes the proper task working during the proper time, can not only make the best use of the ECU, but also predict its capacity rationally. Compared with ordinary algorithm such as clock driven scheduler, static and dynamic priority-driven scheduler as well as round robin scheduler, this paper proposes an offline-designed Blended Timer-triggered Scheduler (BTTS) for AMT control. BTTS can coordinate periodical and event-triggered tasks in one envelope. It designates the available time slice for each task, which can make each critical task run at the proper time.

In this paper, a non-linear, rigid-elastic coupling multi-body system dynamic model is built for a city low-floor bus by using the integration of CAD/CAM/CAE techniques. Finite element analysis models of some flexible components are incorporated to the multi-body vehicle model. The non-linear properties of air spring and dampers are also included. Simulations are carried out in different operation conditions to investigate vehicle ride and handling performances. Based on the comparison of simulation results with field experiment results, the model is validated and the effectiveness of the modeling approach is proved.

The optimal control laws of front and rear wheels for a three-axle vehicle on complex typical path are studied based on the vehicle model of closed-loop control. The steering responses of the vehicle are improved through using steering state feedback. The actual vehicle model is considered as an uncertain system. The cornering stiffness of front and rear wheels and outer disturbances are variable over a limited range. The model-following variable structure control method is used for controlling front and rear wheels steering of the actual vehicle, so that the steering characteristics of uncertain vehicle model can follow the characteristics of reference model. Simulation results have demonstrated that the control system model can cape with the effects of parameter perturbations and outside disturbances.

In this paper, a method of virtual prototyping vehicles with twin-tube hydraulic shock absorbers is developed. The non-linearity of the absorber is studied based on multi-body system dynamics in the ADAMS environment. The unsymmetrical nonlinear hysteretic loop of the velocity characteristics is more accurate and practical than the piecewise linear representation typically used for shock absorber models. In conjunction with the practical geometric and physical parameters and motion restrictions for a car suspension system, the current virtual prototype is employed for dynamic simulation analyses of the absorber, and the numerical results are able to more closely match those obtained from the bench test. The current virtual prototype is validated and can be used as a subsystem for the optimal design of the shock absorber to match the whole car.

Since the nonlinearity which inherently exists in vehicle system need to be considered in active suspension control law design, a new control strategy is proposed for active vehicle suspension systems by using a combined control scheme, i.e., respectively using a PID controller and a fuzzy logic controller in two loops. In this paper, the investigation is mainly focused on vehicle ride comfort performance and simulations in straight running operating condition are presented. The control goal is to minimize vehicle body vertical and pitch accelerations for passenger comfort. The control system consists of two parallel control loops. One loop, using PID control, is to minimize vehicle body vertical acceleration; and the fuzzy logic controller is to minimize pitch acceleration and meanwhile to attenuate vehicle body vertical acceleration further by tuning weighting factors.

In this paper, an investigation is made to the friction clutch engagement control of automotive AMT systems based on a nonlinear dynamic model with double inputs. According to friction torque transmission characteristics during clutch engagement, an equivalent, fully controllable and linearized model and the feedback linearization control are derived from the original system with nonlinearities via homomorphic transforms. By the resulting mathematical modeling, computer simulations are made both for the original nonlinear and feedback linearized systems with incorporation of ordinary PID controllers to follow ideal vehicle dynamic responses. It has been shown by comparison between the two sets of numerical results that the feedback linearization control designed for the nonlinear system is of fine accuracy and robustness in model tracking behaviors of clutch engagements.