外文翻譯--汽車—駕駛系統(tǒng)的研究處理英文版

1、 Handling Studies of Driver-Vehicle Systems M. Lin, A. A. Popov and S. McWilliam School of Mechanical, Materials, Manufacturing Engineering and Management, University of Nottingham, University Park, Nottingham NG7 2RD,

2、 U.K. Email: eaxml@nottingham.ac.uk The driver-vehicle system approach provides a firm basis for analysing vehicle and driver dynamics in vehicle handling design. The paper aims to provide an analysis of driver’s steer

3、ing and speed control during driver-vehicle interaction. Generic mathematical models of vehicle and driver are implemented, and the handling characteristics in typical manoeuvres are studied through numerical simulati

4、ons. As information technology and electronic systems are widely introduced for vehicle chassis control nowadays, new human factor problems have been posed in the simulation for vehicle handling studies. The proposed m

5、odels here provide tools for exploring the effects of active chassis intervention systems on the driver-vehicle. Keywords / driver-vehicle systems, vehicle dynamics, driver behaviour, chassis enhancement systems 1. INTR

6、ODUCTION Recently, as virtual prototyping has been increasingly applied in vehicle development, vehicle handling design in a virtual environment has also been widely used in both academic research and the manufa

7、cturing area. For vehicle handling simulations, vehicle dynamics simulation models (VDSMs) are necessities for the developers. Since 1960’s [3][5][6][11], VDSMs have been developed for a variety of applications,

8、 including dynamic analysis, interactive driving simulation, and vehicle testing. The model complexity and solution procedures are defined according to a given application. It can be seen that the vehicle and driver

9、form a closely coupled man-machine system. The interaction between the dynamics of the vehicle and the driver behaviour plays a paramount role throughout the whole process of the simulation. At the same time, due to

10、 the desire for personal mobility, automotive chassis enhancement systems are introduced into vehicles. They are targeting on providing safety, stability and comfort, and minimising the environmental impacts. However

11、, it is argued that in some cases these chassis enhancement systems can cause more harm than good. In [9], Sharp pointed out that the assessment of driver-vehicle dynamics qualities in the context of electronic enhan

12、ced vehicles contains many separate quality issues and many design conflicts. This involves driver-vehicle speed control and its relationship with directional/steering control, which has only recently received attent

13、ion. A detailed review on automotive chassis enhancement systems in heavy vehicles, provided by Palkovics and Fries [8], includes systems such as anti-lock braking system (ABS), traction control system (TCS), rear ax

14、le steering system and dynamic stability control system. It is suggested that the driver is kept in the control loop as driver’s intention is necessary to activate the systems. By making a vehicle easier to control, d

15、rivers may be encouraged to drive closer to the vehicle limits, therefore affecting the intended safety benefits. In the following sections, a basic 4-DOF (longitudinal, lateral, yaw, roll) vehicle model and a drive

16、r control model are presented. The driver model is directionally structured to control vehicle heading/yaw angle and lateral position, and longitudinally perceiving the longitudinal acceleration error. In Section 4, d

17、river- vehicle interaction is reviewed. The simulation is then employed in Section 5 to analyse manoeuvres involving double lane change and braking in turn. 2. VEHICLE MODEL The vehicle is represented by a four degrees

18、 of freedom model [4], for the longitudinal, lateral, yaw and roll motion. As shown in Fig. 1, although the suspensions are not included in the modelling, the model uses a simplified description of body roll assumin

19、g a fixed roll axis defined by the heights of the roll centres of the front and rear axles of the vehicle. Vehicle model parameters are reported in the Appendix. The equations of motion using axes fixed to the vehicl

20、e body are given by, δ δ sin cos ) ( yf F xf F xr F rv u m ? + = + ?δ δ sin cos ) ( xf F yf F yr F ru v m + + = + ?) sin cos ( sin) sin cos (δ δ φδ δyf F xf F xr F hyr F b xf F yf F a p xz I r z I? + ?? ? + ? = ? ? ? ? ?

21、) sin cos ( cos) ( sin) ( ) (δ δ φφφ φ φ φ φxf yf yrzr zfr f r f xz xF F F hF F hp c c k k r I p I? + ++= + + + + ? ? ? ? ?(1) more difficult and imprecise than the perception for horizontal curvature. 3.1 Directional/

22、Steering Control For driver’s visual feedback, a two-level (preview and compensatory) driver steering model based on the control strategy proposed by Donges [3] is presented here. The driver exerts steering control t

23、o maintain lane position through preview control, and to manoeuvre the vehicle during curve negotiation, lane change or obstacle avoidance. Unpredictable road disturbances can randomly move the vehicle within the

24、 lane, and the driver must counteract these disturbances with compensatory control. For preview control, Weir and McRuer [12] suggested that, systems structured to control vehicle heading/yaw angle and lateral

25、position or path angle and lateral position offer good closed-loop characteristics. Therefore, it is assumed here that the driver develops steering corrections based on perceived heading/yaw and lane position errors.

26、 By setting a preview point P on the vehicle-fixed x axis, a sort of predictive behaviour is incorporated into the system. Fig. 2 illustrates driver’s behaviour through path preview. A composite heading error of the

27、preview point relative to the desired path at the preview point is given by, ) ( / P P e c L y ψ ψ ψ ? + =(6) where ye is the lane position error, LP is the preview distance, ψ is the heading angle and P ψis the head

28、ing angle between x axis and AP line. Instead of separately perceiving both heading and lane position errors, the driver needs only to perceive the angular error c ψ to the preview point down the road. The preview di

29、stance LP here is the product of vehicle forward speed and preview time constant TP. This is consistent with our everyday experience that driver sees nearer distance at lower speeds and further distance at higher spe

30、eds. Following McRuer’s crossover model [6], driver’s compensatory feedback control can be defined by the transfer function of the steering angle to the composite heading error, sILc e s Ts T G ss τ ψδ ? ++ = ) 11 (

31、) () ((7) It includes three components: a gain G which sets the magnitude of road steering angle δ corrections for given heading error c ψ ; a lead term ) 1 ( + s TL that the driver adopts to counteract vehicle tyre

32、delay; a lag term ) 1 ( + s TI corresponding to the neuromuscular delay; and , a time delay s e τ ? approximating driver’s reaction time delay. For driver’s motion feedback, it provides information on motion p

33、erformed by human organs and on orientation with respect to the gravitational direction. In [1], Allen noted that the yaw rate information can be used as a motion feedback element. The motion feedback gain Km provide

34、s a lead that the driver can use to compensate for the vehicle yaw rate lag. 3.2 Speed Control Speed control is important in a variety of scenarios, including maintaining safe lateral acceleration levels while follo

35、wing curved paths, responding to speed limits, and slowing down during emergency avoidance. During straight running the driver continues at specified speed. When the driver detects curvature, speed is then reduced ac

36、cordingly in order to maintain desired lateral acceleration. The driver speed control law can then be described as Fig.3 (a). The driver commands deceleration consistent with a desired speed change, and perceives dec

37、eleration errors. Especially, when electronic chassis controls, such as ABS, TCS, etc., are involved, speed control will be essential. As we can see from the operating principles of these control systems, most of the

38、m are activated under emergency situations. Speed changing is therefore inevitable. For example, by adding an effective ABS, the relationship between the brake pedal force and vehicle deceleration is illustrated in F

39、ig.3 (b). With the application of this relationship and the speed control law described above, the assessment of effects of these electronic controls is feasible. Ac ψPreview point P P ψ ψ ?ψLP y x XYye / LP Desire