JP2762565B2 - Wing control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a wing control device for an automobile.

2. Description of the Related Art A conventional wing control device for a vehicle is disclosed in, for example, Japanese Utility Model Laid-Open No. 6-101078.
When the steering mechanism is steered at a certain angular speed or more, provided that the vehicle speed is a certain speed or more, the wing control device rotates the vertical wing by a predetermined angle according to the steering direction, and the wind pressure applied to the vertical wing This is to maintain the posture of the vehicle body in a stable state aerodynamically.

(Problems to be Solved by the Invention) However, in such a conventional wing control device, the vertical wing is set at a predetermined angle in accordance with the steering only when the vehicle speed is equal to or higher than a certain value and the steering angular speed is equal to or higher than a certain value. Since the vehicle is merely rotated, nonlinear characteristics such as changing the yaw rate when the vehicle receives a crosswind are not taken into consideration, and there is a problem that higher responsiveness and stability cannot be obtained.

Further, when the vehicle is traveling straight without steering, the vertical wing is fixed, so that the vertical wing cannot be positively used for a change in the yaw rate due to disturbance such as a cross wind.

Therefore, an object of the present invention is to provide a wing control device capable of further improving responsiveness and stability by controlling feedback of detected yaw rate.

[Constitution of the Invention] (Means for Solving the Problems) In order to achieve the above object, the present invention provides a vertical wing provided on a vehicle body so as to be rotatable in a horizontal direction, and a driving means for rotating the vertical wing. A yaw rate detecting means for detecting a yaw rate of the vehicle, and a control means for controlling the driving means in accordance with a yaw rate feedback amount reduced in accordance with an increase in vehicle speed based on an output signal of the yaw rate detecting means. It is characterized by the following.

(Operation) According to the above configuration, since the yaw rate of the vehicle is detected and the yaw rate feedback control is performed, it is possible to perform the control taking in the yaw rate change due to the cross wind or the like.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 2 to 10.

First, the structure will be described. As shown in FIG. 2, a vertical wing 5 is provided on an upper surface of a trunk lid 3 of a vehicle body 1 having a front wheel as a steering wheel so as to be rotatable in a horizontal direction. The vertical wing 5 is supported on the trunk lid 3 so as to be rotatable about a shaft 7 as shown in FIG. A gear 9 is integrally attached to the end of the shaft 7, and this gear 9 meshes with a gear 13 of a step motor 11 which is a driving means attached to the vehicle body in the trunk room. Accordingly, the step motor 11 is driven to drive the gear 13
When forward or reversing the rotation angle of the gear 13 is boosted by the gear 9, the vertical wing 5 through a shaft 7 is left in the range of theta _R from theta _L in the horizontal direction about the neutral position theta _M To rotate. The drive of the step motor 11 is controlled by a microcomputer 15 as control means.

As shown in FIG. 4, the microcomputer 15 is connected to a gyroscope 17 as a yaw rate detecting means for detecting a yaw rate and a vehicle speed sensor 19 as a vehicle speed detecting means for detecting a vehicle speed. A connected output interface 23, a ROM 25 storing a control program and control values, a RAM 27 for temporarily storing external data and operation results, a CPU 29 for performing arithmetic processing for control, and a data bus 31 for connecting these. And

 Next, the operation of the above embodiment will be described.

 Here, a description will be given using the model shown in FIG.

Here, l: wheel base lf: distance between center of gravity Y and front wheel axle FO lr: distance between center of gravity Y and rear wheel axle RO lw: distance between center of gravity Y and vertical wing 5 M: Mass of the vehicle I: Moment of inertia of the vehicle: Yaw rate (ヨ ー: Yaw angle) V: Vehicle speed: Lateral speed at the center of gravity Y k _φ : Yaw rate feedback gain, and the wing specifications ρ: Air density C _L : Lateral force coefficient per radian of wing S _W : Area of wing Is represented by

Here, when each expression is Laplace transformed and arranged, Becomes Here, θ is the steering angle of the front wheels.

The denominator of the solution of ψ (S) / θ (S) is And the molecule is Becomes Summarizing the above Can be expressed as

In other words, the effect of applying the yaw rate feedback would appearing only by items that are relevant to 2ξ _n · W _n and W _n ^2.

That is, 2ξ _n · W _n , W _n ² is Is represented by

In other _words, k φ is if it is large, it is possible to the 2ξ _n · W _n and W _n ² as large.

further, And hence, It is.

As evident by the above equation, by applying the yaw rate feedback, it becomes possible to a large and 2ξ _n · W _n and ▲ W ² _n ▼, shown in steering frequency characteristic diagram of FIG. 6 As described above, it is possible to obtain a vehicle characteristic having a high natural frequency and excellent damping.

Further, the vertical wing 5 is controlled not only when the vehicle is steered but also when the yaw rate is changed due to a side wind or the like.
Control can be performed in consideration of the non-linear characteristics of the vehicle.

On the other hand, since the feedback amount is proportional to the square of the vehicle speed (V ² ), the steering frequency characteristic improves at high speeds,
Conversely, as shown by the broken line in FIG. 7, the yaw rate feedback gain may be high and the understeer tendency may be increased.

Therefore, the wing control device according to this embodiment, as shown in the characteristic diagram of Figure 8, gradually reduced yaw rate feedback gain k _phi is fast, while ensuring stability in low and medium speed, and The response gain is obtained while securing the stability at high speed.

The yaw rate feedback control operation according to the vehicle speed will be described with reference to the flowchart of FIG.

The processing shown in this flowchart, for example, is started when the ignition switch is operated to an ON position, first the microcomputer 15, a yaw rate [psi _i detected by the gyroscope 17, the vehicle speed V _i detected by the vehicle speed sensor 19 Read (step S1). Next, operation based on the yaw rate feedback gain k _.phi.i according to the vehicle speed V _i to the characteristic of FIG. 8 (step S2). Then, by multiplying the yaw rate [psi _i the yaw rate feedback gain k _.phi.i determined in step S2 obtains the rotation angle alpha _i of the vertical wing 5 (step S3), and the step motor a pulse signal corresponding to the rotation angle alpha _i Output to 11 (step S4). Step motor 11 by the output signal is driven, rotation angle vertical wing 5 construed gear 13, 9 alpha _i
Is rotated.

As described above, according to the above-described embodiment, when the front wheels are steered, the yaw rate ψ and the vehicle speed V of the vehicle are detected, and the yaw rate feedback control is performed in accordance with the vehicle speed V, and the vertical wing 5 moves in the steering direction of the front wheels. Due to the rotation, the vehicle pressure can be aerodynamically held in a stable state by the wind pressure applied to the vertical wing 5. Accordingly, it is possible to obtain desirable responsiveness to steering and stability of the vehicle attitude in all vehicle speed regions.

Also, in such yaw rate feedback control, when steering is not performed, when a yaw rate that disturbs the straightness of the vehicle such as a cross wind occurs, as shown in FIG.
Since the vertical wing 5 is rotated so as to generate a moment M in a direction in which the vertical wing is returned, straightness can be improved as compared with a case where the vertical wing 5 is simply fixed in the straight traveling direction.

Furthermore, although the vehicle includes various non-linear characteristics, since the yaw rate generated from the non-linear characteristics is also fed back, appropriate control is performed by reflecting the state of the vehicle as a result. Will be.

[Effects of the Invention] As is clear from the above description, according to the configuration of the present invention, the rotation of the vertical wing is controlled by feeding back the yaw rate by an amount reduced as the vehicle speed increases. Thus, it is possible to secure a response gain at a low speed while securing stability at a high speed. Therefore, it is possible to obtain desired responsiveness to steering and stability of the vehicle attitude, while considering various non-linear characteristics of the vehicle, and improve straightness.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of the present invention, FIG. 2 is a plan view of an automobile having a wing control device according to an embodiment of the present invention, FIG. 3 is a schematic configuration diagram of the wing, and FIG. 4 is a wing control device. 5, FIG. 5 is a diagram for explaining the operation of the two-wheel model, FIG. 6 is a steering frequency characteristic diagram, FIG. 7 is a diagram showing the relationship between vehicle speed and yaw rate steady-state gain, and FIG. 8 is a diagram showing the relationship between vehicle speed and yaw rate feedback gain. FIG. 9 is a characteristic diagram showing the relationship, FIG. 9 is a flowchart based on the circuit diagram of FIG. 4, and FIG. 10 is an operation explanatory diagram based on a two-wheel model. 1 ... body 5 ... vertical wing 11 ... step motor (driving means) 15 ... microcomputer (control means) 17 ... gyroscope (yaw rate detecting means) 19 ... vehicle speed sensor (vehicle speed detecting means)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 62-99480 (JP, U) JP-A 61-101078 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B62D 37/02

Claims (1)

(57) [Claims] 1. A vertical wing rotatably provided on a vehicle body in a horizontal direction, a driving means for rotating the vertical wing, a yaw rate detecting means for detecting a yaw rate of the vehicle, and an output signal of the yaw rate detecting means. Control means for controlling the driving means in accordance with the yaw rate feedback amount reduced in accordance with an increase in the vehicle speed based on the vehicle speed.