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In partially automated and conditionally automated vehicles, a part of the work of human drivers is replaced by the system, and the main source of safety risks is no longer system failures, but non-failure risks caused by insufficient system function design. The absence of unreasonable risk due to hazards resulting from functional insufficiencies of the intended functionality or by reasonably foreseeable misuse by persons, is referred to as the Safety Of The Intended Functionality. Drivers have the responsibility to supervise the automated driving system. When they don't agree with the operation behavior of the system, they will interfere with the instructions. However, this may lead to potential risks.

An EV prototype, with all the wheels respectively driven by 4 inwheel motors, is developed, and undergoes a series of practical measurements and road tests. Based on the obtained vehicle parameters, a multi-body dynamics model is built by using SolidWorks and Adams/Car, and then validated by track test data. The virtual prototype is served as the control plant in simulation. An adaptive fractional order PID (A-FO-PID) controller is designed to enhance the handling and stability performance of the EV. Considering the model uncertainties, e.g. the variation in body mass distribution and the consequent change in yaw moment of inertial, a Parameter Self-Adjusting Differential Evolution (PSA-DE) algorithm is adopted for tuning the controller parameters, i.e. KP, KI, KD, λ and μ. As a modification of traditional DE algorithm, the so-called Variance of Population’s Fitness is utilized to evaluate the diversity of the population.

An energy-regenerative vehicle suspension is proposed. Permanent-magnet direct-current motors are utilized as the active actuators in automotive suspension. The significant characteristic of the suspension is that vibration energy from the road excitation can be regenerated and transformed into electric energy while good suspension performance can be maintained. The modeling of electrical suspension system has been completed and simulated in Matlab/Simulink. The motor actuator working as a generator is proved to maintain the performance of vibration control and energy-regeneration. The prototype of motor actuator is designed and made. The vibration absorption and regeneration performances are verified by full-vehicle experiments.

A new kind of integrated semi-track air-cushion pitch controller is proposed in this paper. The controller first compute the target working point based on a weighed function, which is the combination of optimal power consumption and pitch angle control demand. Then the sequential quadratic programming algorithm distributes the general target values to specific control values. The performance of the controller is verified through co-simulation between Matlab/Simulink and ADAMS/View. The simulation results show the effectiveness of the control algorithm and the correctness of the choice in physical configuration with two air cushions for vehicle body pitch control.

A semi-track air-cushion vehicle (STACV) which combines an air-cushion lifting system with a semi-track propulsion system is an efficient solution for heavy-duty vehicles working on soft terrain, such as the vehicles for agricultural, oil industrial and military purposes. Focusing on optimizing fuel economy of the vehicle, five main issues are studied in this paper. Firstly, based on the analyses of resistances for the STACV in a sandy loam working condition, a theoretical model for fuel consumption of 100km, which is an evaluation index for fuel economy, is established. Secondly, through simplified by a group of constraint equations based on the physical structure of the vehicle, the running parameters and control target (fuel consumption of 100km) could be expressed by the following two measurable and adjustable parameters, fan rotational speed and vehicle forward speed.

To optimally allocate control authorities to co-existing active actuators, an integrated chassis controller with main/servo-loop structure is designed to coordinate direct yaw moment control and active steering. Firstly, a sliding mode controller in the main-loop calculates the desired stabilizing forces. Then in the servo-loop, by directly considering limits of road friction and actuators, a quadratic programming based control allocation approach is adopted to reasonably and optimally distribute these deisired forces to tire actuator actions. Co-simulation of Matlab/Simulink and Carsim clarifies that the proposed controller could significantly improve vehicle handling performances.

In this paper, we proposed a novel integrated vehicle chassis control configuration, which is based on the combination of vehicle vertical and lateral motion controls. Focusing on the improvement of vehicle handling and riding performance, particularly the active safety under critical driving condition, the purpose of Active Suspension (AS) in the integrated system is to achieve ride comfort quality and to provide more tyre cornering ability near the cornering force saturation regions, while the effect of Four Wheel Steering (4WS) is expected to eliminate the body side slip angle and to achieve an ideal yaw rate model following.

First, the energy consumption of a passive suspension via damper and the energy demand for an LQG optimal vehicle active suspension are investigated, showing valuable potentials for an active suspension with vibration energy regeneration. Then, the feasibility of energy regenerative approaches is discussed, and an electrical active suspension configuration is proposed with the description of its working principle and structure. The study on feasibility and configuration shows that the proposed configuration and control approach can be an effective approach for the active control and the energy regeneration of vehicle vibration. And potentially, it also can be useful for future electrical suspension design of electrical vehicles.

For the purposes of on-line control, e.g., in an automatic driving system, or of closed-loop directional control simulation, an optimal preview artificial neural network (ANN) driver model based on error elimination algorithm(EEA) is built. Then the optimal preview times are discussed in high frequency range in this system. The simulation results of optimal preview ANN driver model and Error Elimination Algorithm driver model are compared under the condition of different vehicle speeds and paths, which shows that the proposed approach is efficient and reliable enough, particularly for driver-vehicle closed-loop system.

The study in the paper is aimed to develop a yaw stability controller (YSC) by way of actively dynamic distribution of the longitudinal tire forces, which is considered to be one of the promising means of chassis control, so as to substantially improve the vehicle active safety even under some critical conditions. The control law, which ensures the vehicle follow the desired dynamic model via the feedforward control of side slip angle and the fuzzy control of the errors between the desired states and the corresponding practical ones, has been designed and implemented by using the hardware-in-the-loop (HiL) simulation technology under the Matlab/Simulink environment.

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.

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.

A new design method is proposed for a semi-tracked air-cushion vehicle for soft terrain by using a flexible bind, which offers more flexibility in designing. This paper describes the design principle focusing on optimizing the total power consumption of the vehicle. The relationships of load distribution and power consumption are analyzed. The prototype experiments showed that the proposed design can meet the demand of tractive and transport efficiency with its optimal state of using minimum total power consumption and meanwhile maintaining ride comfort.

This paper presents the algorithm for a Kalman filter active vehicle suspension design. Based on simulations, two main issues have been investigated, (a) the effects of disturbances from the changes in road input and the variations of vehicle parameters on state observer estimation, (b) the benefits of adaptation of an active suspension to the changes of road input and the variations of vehicle parameters. Simulations showed the significant vehicle performance improvement from adaptation to road input; however, an adaptive Kalman filter is not very necessary.