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The purpose of this study is to propose a torque vectoring control system for improving the handling stability of distributed drive electric buses under complicated driving conditions. Energy crisis and environment pollution are two key pressing issues faced by mankind. Pure electric buses are recognized as the effective method to solve the problems. Distributed drive electric buses (DDEBs) as an emerging mode of pure electric buses are attracting intense research interests around the world. Compared with the central driven electric buses, DDEB is able to control the driving and braking torque of each wheel individually and accurately to significantly enhance the handling stability. Therefore, the torque vectoring control (TVC) system is proposed to allocate the driving torque among four wheels reasonably to improve the handling stability of DDEBs.

The proposed TVC system is designed based on hierarchical control. The upper layer is direct yaw moment controller based on feedforward and feedback control. The feedforward control algorithm is designed to calculate the desired steady-state yaw moment based on the steering wheel angle and the longitudinal velocity. The feedback control is anti-windup sliding mode control algorithm, which takes the errors between actual and reference yaw rate as the control variables. The lower layer is torque allocation controller, including economical torque allocation control algorithm and optimal torque allocation control algorithm.

The steady static circular test has been carried out to demonstrate the effectiveness and control effort of the proposed TVC system. Compared with the field experiment results of tested bus with TVC system and without TVC system, the slip angle of tested bus with TVC system is much less than without TVC. And the actual yaw rate of tested bus with TVC system is able to track the reference yaw rate completely. The experiment results demonstrate that the TVC system has a remarkable performance in the real practice and improve the handling stability effectively.

In view of the large load transfer, the strong coupling characteristics of tire , the suspension and the steering system during coach corning, the vehicle reference steering characteristics is defined considering vehicle nonlinear characteristics and the feedforward term of torque vectoring control at different steering angles and speeds is designed. Meanwhile, in order to improve the robustness of controller, an anti-integral saturation sliding mode variable structure control algorithm is proposed as the feedback term of torque vectoring control.

This study aims to propose an improved linear quadratic regulator (LQR) based on the adjusting weight coefficient, which is used to improve the performance of the vehicle direct yaw moment control (DYC) system.

After analyzing the responses of the side-slip angle and the yaw rate of the vehicle when driving under different road adhesion coefficients, the genetic algorithm and fuzzy logic theory were applied to design the parameter regulator for an improved LQR. This parameter regulator works according to the changes in the road adhesion coefficient between the tires and the road. Hardware-in-the-loop (HiL) tests with double-lane changes under low and high road surface adhesion coefficients were carried out.

The HiL test results demonstrate the proposed controllers’ effectiveness and reasonableness and satisfy the real-time requirement. The effectiveness of the proposed controller was also proven using the vehicle-handling stability objective evaluation method.

The objective evaluation results reveal better performance using the improved LQR DYC controller than a front wheel steering vehicle, especially in reducing driver fatigue, improving vehicle-handling stability and enhancing driving safety.

This paper studies the lateral stability regulation of intelligent electric vehicle (EV) based on model predictive control (MPC) algorithm.

Firstly, the bicycle model is adopted in the system modelling process. To improve the accuracy, the lateral stiffness of front and rear tire is estimated using the real-time yaw rate acceleration and lateral acceleration of the vehicle based on the vehicle dynamics. Then the constraint of input and output in the model predictive controller is designed. Soft constraints on the lateral speed of the vehicle are designed to guarantee the solved persistent feasibility and enforce the vehicle’s sideslip angle within a safety range.

The simulation results show that the proposed lateral stability controller based on the MPC algorithm can improve the handling and stability performance of the vehicle under complex working conditions.

The MPC schema and the objective function are established. The integrated active front steering/direct yaw moments control strategy is simultaneously adopted in the model. The vehicle’s sideslip angle is chosen as the constraint and is controlled in stable range. The online estimation of tire stiffness is performed. The vehicle’s lateral acceleration and the yaw rate acceleration are modelled into the two-degree-of-freedom equation to solve the tire cornering stiffness in real time. This can ensure the accuracy of model.

The purpose of this paper is to develop a combined control (CC) technique based on the direct torque control (DTC) strategy and vector control (VC) method, to improve the overall performance of a three-phase induction machine (TPIM) drives.

The proposed control scheme includes a table-based DTC strategy in connection with a proportional-integral-sliding mode controller and pulse width modulation switching strategy. The control system has merits of DTC technique such as simple structure, less dependent on machine parameters, fast dynamic response and merits of VC technique such as high accuracy and constant switching frequency.

To validate the effectiveness of the proposed control system, simulation and experimental studies are carried out for a 0.75 kW TPIM in different operating conditions. The achieved results show the superiority of the proposed method in terms of fast dynamics and simple structure compared to the VC strategy and low speed and torque ripples and constant switching frequency compared to the DTC method.

Compared to the conventional CC strategies, the control law of the proposed method is based on DTC theory and modulation is established based on VC. In other words, the variable switching frequency which is one of the main disadvantages of the conventional CC strategies is rectified using the proposed CC scheme.

THE complete study of the tail spin divides itself into four distinct parts: the entry into the spin, the steady spin maintained by the action of the controls, the uncontrolled spin, and the recovery from the spin. In this paper we will limit ourselves to the study of the uncontrolled tail spin, i.e., the spin which has reached the state of steady motion, and persists in it with controls neutralized, or even against controls. When we speak about steady motion, we imply that all forces and moments are in a state of complete equilibrium, and that there are no accelerations. The study of the uncontrolled spin is therefore the study of equilibrium in spin. If the proportions of an aeroplane are such as to make possible equilibrium in spin with controls set for recovery, there evidently will be no recovery, because recovery means lack of balance and resulting acceleration. In order to be safe the aeroplane must be proportioned so as to make equilibrium in tail spin impossible, unless the controls are set lor spinning.

WITH tailless aeroplanes, all known aerodynamic control devices possess the peculiarity of not only producing moments about one axis, but of also causing secondary moments about one or both of the other axes. Horizontal controllers forming part of the wing near the tips in wings having sweep‐back or sweep‐forward, for instance, do not produce rolling moments alone, when differ‐entially deflected; they also cause yawing and pitching moments. Similarly, wing‐tip disk rudders operated on such wings not only produce yawing moments, but may cause rolling and even pitching moments.

THE complexity of the problems which are associated with the lateral stability and directional control of tailless aeroplanes was not realized until rather late.

The third term has been expressed as but in wind tunnel work it is often more convenient to measure were the omission of the dash signifies that the moment is now measured about a wind axis. The two quantities are very closely related and the measurement of one tells us almost as much as if the two were known. The latter, however, tells us either directly or indirectly what effect the addition of fin and rudder will have on the autorotation properties of the wings alone. The damping of fin and rudder being due essentially to the air flow meeting them at an angle on account of the rotation it should theoretically be possible to deduce this dynamic quantity from a simple static test of moment due to yaw angle. An experiment to test this was carried out several years ago but the static test did not give any approximation to the truth. This was ascribed at the time to the shielding of fin and rudder by the tail plane in the rotative experiment and subsequent work has amply confirmed this view. It is now known that shielding by the tail plane is by far the most important factor in determining the efficiency of the vertical surfaces at high angles of attack.

This booklet, available free of charge from Inspection Equipment, 19 Broad Court, Drury Lane, London, W.C.2, is a condensed report of the proceedings of the Second Conference on Aircraft Radiography held in Copenhagen from October 9–12, 1956.

FROM the early clays of flying, aeroplanes have been provided with surfaces intended to give separate control about the rolling and yawing axes. In practice, however, the control surfaces themselves and the stability characteristics of the aeroplane combine to defeat the independence of rolling and yawing control. Recognition of this fact has lately resulted in attempts to arrange the stability characteristics of the aeroplane so that a combined rolling and yawing motion, of the type required in normal flying, is produced by only one control surface.