JPS6076413A - Apparatus for presuming neutral position of steering gear of vehicle - Google Patents

Abstract

PURPOSE:To improve the accuracy in determination of the neutral position of a steering gear by calculating the neutral position on the basis of the operating direction and amount of the steering gear when the change in forward, backward, left and right behavior of a vehicle is less than a reference value determined by the vehicle speed. CONSTITUTION:A calculation control circuit 1 receives respective input signals from a vehicle speed sensor 2, a steering sensor 3, a brake detector 4 and an acceleration detector 5 to calculate and judge vehicle speed V, data omega of operating direction and displacement of a steering gear, data theta of acceleration and the presence of braking according to a predetermined program. On the basis of the result, the neutral position omega CENT of a steering gear is calculated. Then, said circuit 1 judges the degree of rolling phenomenon to generate required damping force intensifying signals to drive circuits 10-13 of shock absorbers 6-9 for controlling shock absorbers 6-9. By this constitution, the accuracy in determining the neutral position of the steering gear can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a device for estimating the neutral position of a steering wheel in a vehicle traveling device, and is intended to be used for vehicle traveling control.

[Background] In a vehicle travel control device that requires steering information, the steering control device (steering link wheel)
It is said that an estimation method as exemplified in (2) of Japanese Patent Laid-Open No. 58-41270 is preferable to a potentiometer that responds to the rotation angle of the rotation angle. However, in this method,
It has been difficult to constantly determine the neutral position with high precision in response to driving conditions that change depending on road conditions and the driving method of each driver.

[Object of the Invention] In view of the above, an object of the present invention is to provide a steering neutral position estimating device for a vehicle that can determine a neutral position with high accuracy in accordance with driving conditions.

[Structure of the Invention] In order to achieve this object, the present invention provides a first signal that generates a first signal that changes depending on the operation direction and operation movement amount of a steering operation device of a vehicle, as shown in FIG. a signal generating means St, a second signal generating means S2 for generating a second signal that varies depending on the running speed of the vehicle, and a signal establishing a third signal related to longitudinal or lateral dynamic changes of the vehicle. establishing means S3; and determining means for determining whether the dynamic change is greater than a reference value determined according to the traveling speed of the vehicle (3) according to the second signal and the third signal; The present invention is characterized by comprising a calculating means C which calculates the neutral position of the steering operating device based on the first signal when the dynamic change is smaller than the reference value in the determination result.

In this configuration, the signal establishing means S3 is configured to be related to a dynamic change in at least one of the front and rear or left and right sides of the vehicle, and for example, the signal establishing means S3 is configured to respond to a change in the operating angle of the steering device in response to the first signal. By including a means for calculating a change in movement and using the calculation result as data representing the dynamic change, a third signal can be obtained in relation to a change in left and right movement of the vehicle. Further, by including means for using the acceleration obtained by calculating the acceleration of the vehicle as data representing the dynamic change, it is possible to obtain a third signal related to the dynamic change in the front and rear of the vehicle.

[Effects of the Invention] Therefore, according to the present invention, when driving at high speed, the operating angle of the steering operating device is originally small, compared to when driving at low speed (4). By calculating the neutral position based on the amount of movement of the steering operation (the amount of movement of the steering wheel) and when driving at low speeds, the neutral position is calculated based on the larger dynamic change, so that the vehicle can move straight by determining conditions that match the actual driving conditions. It is possible to determine whether the vehicle is traveling and to calculate the neutral position with higher accuracy.

〔Example〕

The features of the present invention described above and other features will be explained in detail with reference to the following examples.

FIG. 2 shows the overall configuration of a vehicle suspension control device to which the present invention is applied.

In FIG. 2, reference numeral 1 represents an arithmetic control circuit that adjusts input signals and output signals according to a preset control program.

The arithmetic control circuit 1 has a microcombiator (5) for connecting input and output to this microcomputer and a microcombiator that realizes the above-mentioned discrimination means (D) and arithmetic means (C) by executing a control program. The main components are peripheral circuits used in

The arithmetic control circuit 1 includes a vehicle speed sensor (
A drive circuit 10.11.1 is connected to a second signal generation means) 2, a steering sensor (first signal generation means) 3, a braking detector 4, and an acceleration detector 5, and serves as an output signal means.
2.13 are connected to each of the drive circuits 10 to 13, and an electromagnetically actuated variable damping force shock absorber 6.7.
8.9 are operatively connected. The arithmetic control circuit 1 is configured to be supplied with power from the vehicle battery Batt via the key switch 14, and therefore includes a circuit that stabilizes the power supply voltage and a reset circuit that resets the micro combiator at the rise of the stabilized voltage. I'm here.

Among the above configurations, the vehicle speed sensor 2 is configured using a photoelectric conversion method, an electromagnetic pickup method, or a contact method, etc., and is installed in a transmitter (not shown) to generate a pulse signal synchronized with the rotation of the gear, and detect the vehicle speed based on the frequency of the pulse signal. , the distance traveled can be determined from the number of pulse signals.

The steering sensor 3 is configured using a photoelectric conversion method, an electromagnetic pickup method, a contact method, or the like, and is disposed on a steering shaft (not shown), and generates a pulse signal with a frequency proportional to the angular velocity of movement of the steering wheel. FIG. 3 is a diagram showing the relationship between the steering sensor 3, which uses a photoelectric conversion method, and the steering shaft 15, which is linked to the steering operation. The sensor 3-1.3-2 is provided with a rotary body 16 that rotates according to the rotation of the steering shaft 15, and is disposed at a position opposite to the sensor 3-1.3-2 with the rotary body 16 in between. Light emitted from a light source (not shown) is received by the sensor 3-1, 3-2 and blocked by the rotation of the rotating body 16.

Therefore, when the rotating body 16 rotates clockwise, the sensor 3
The output waveforms of the sensor 3-1 and the sensor 3-2 are as shown in FIG.
As is clear from both output waveforms, the direction of rotation of the steering shaft 15 can be determined from the positive and negative phases of the output waveforms of the sensors 3-1 and 3-2. Also, from the number of output waveform pulses, the movement angle (w
It is possible to know the A operation amount and further to know the moving angular velocity (operation speed) from the frequency of the output waveform.

The brake detector 4 uses a stop lap switch that is linked to the operation of the brake pedal, and generates a signal indicating whether or not the brake pedal is operated.

The acceleration detector 5 is composed of a potentiometer or a group of a plurality of contacts, and outputs a voltage or a digital signal corresponding to the amount of depression of the accelerator pedal.

The structure of each of the shock absorbers 6 to 9 is as schematically shown in cross-section in FIG. 4, for example. In FIG. 4, the drive circuit 10.
11. A coil 21 is electrically connected to 12 or 13, and a ring-shaped core 23 is moved and held upward together with the connecting rod 22 by the magnetic force generated when the coil 21 is energized. It is being

When the coil 21 is in a non-energized state, the flow control valve 24 at the tip of the connecting rod 22 and the piston 26 provided at the tip of the piston rod 25 are maintained in the state shown in the figure.
Oil is allowed to flow relatively smoothly between the first oil chamber 40 and the second oil chamber 50. In other words, the damping force of the shock absorber 6, 7, 8 or 9 is maintained at a normal level, ie at a low level. That is, shock absorber 6.
7.8 or 9 is maintained as a weak damper, ie, soft.

On the other hand, when the coil 21 is energized by the drive circuit 10, 11, 12 or 13, the core 23 receives an upward force due to the generated magnetic force, and together with the core 23, the connecting rod 22
moves upward and the flow rate control valve 24 closes the passage 28 that communicates the first oil chamber 40 and the valve chamber 27, thereby reducing the flow resistance between the first oil chamber 40 and the second (9) oil chamber 50. becomes a high level, and therefore the damping force of the lock absorber 6, 7, 8 or 9 becomes high. While the coil 21 is energized, the flow control valve 24 continues to block the passage 28, and the damping force of the shock absorber 6, 7, 8 or 9 is kept high, ie, a strong damper.

Next, the processing operation of this embodiment configured as described above will be explained. When the key switch 14 is turned on, the microcomputer in the arithmetic control circuit 1 starts processing as schematically illustrated in FIG.

That is, in the initial set routine 100, the variable data in the internal memory is set to a predetermined initial value.Then, the cyclic programs shown in routines 200 to 600 are executed.

In the data input routine 200, the computer executes the following processes (a) to (d) for storing various signals from the input signal means 2 to 5 as internal data.

(+1) Data V(t) (hereinafter referred to as vehicle speed) representing the traveling speed of the vehicle is calculated. In this case, an interrupt program (not shown) that is started every time a pulse signal from the vehicle speed sensor (10) sensor 2 is inputted calculates the change over time in the count data of the free run counter that is stored sequentially. This allows the vehicle to travel a certain distance (determined by the vehicle speed sensor)
Calculate the time it takes to move. Then, the vehicle speed V (t) is calculated by dividing the predetermined distance by the calculated time. Note that in the interrupt program, a distance variable β, which will be described later, is incremented (+1) each time.

(bl Calculate the data ω(t) (hereinafter referred to as the operation angle) representing the operation direction and operation movement amount of the steering controller. In this case, two pulse signals from the steering sensor 3 are monitored, and the rise and fall of the pulse signals are The operation angle ω(1) is added or subtracted every time the pulse signal falls.At this time, the sign is determined by checking the phase difference according to the order of the rise and fall of the pulse signal.The operation angle ω(t') In the initial set routine 100,
It is assumed that an appropriate value (for example, a value corresponding to the neutral position of the steering device under normal conditions) is set.

(C1 Calculate data θ(1) (hereinafter referred to as acceleration) representing the magnitude of vehicle acceleration. In this case, the degree of temporal change in the input signal from acceleration detector 5 can be calculated using a general method. .

It is determined whether or not +di braking is being performed based on the input signal from the braking detector 4, and the determination result is stored.

Now, in routine 300, the microcomputer calculates the neutral position ωCENT of the steering operating device. The details of this processing are shown in FIG. 7, and the details of the calculation will be described later.

The computer determines the degree of rolling phenomenon in the vehicle based on the results calculated in routine 300 and the data input in routine 200, and when it determines the conditions under which rolling of a predetermined magnitude or more occurs, the computer A command signal for making the damping force of the absorbers 6 to 9 a strong damper is created internally. Although not explained in detail, the judgment conditions at this time can be determined as follows, for example: ■ The operation angle ω(1) is outside the range of the calculated neutral position ωCENT plus a predetermined angle ±α. thing.

(2) The amount of change over time in the operating angle ω(1) (the difference between the latest calculation result and the previous calculation result) is larger than the preset value β. However, the set value β may be calculated as a function of the vehicle speed V (t) so that it decreases as the vehicle speed V (t) increases.

■The amount of change over time in the operating angle ω(1) is the neutral position ωCEN
The sign should change in the direction away from T.

When all of these judgment results are positive, a command signal is created to set the damping force to a strong damper, and after a preset time has elapsed since this condition is denied, the damping force is set to a weak damper. A command signal is created to

The computer then generates command signals in routine 500 to adjust the damping force according to other control conditions. In this case, for example, it is determined whether the acceleration θ(1) exceeds a preset value γ (this may be a function of the vehicle speed V(t)), and the damping force is applied to a strong damper in a sudden acceleration state. It is possible to create a command signal to set the damping force to a strong damper when braking is in progress.

Next, in step 600, the computer provides an output signal for switching the damping force to the shock absorbers 6 to 9 in accordance with the previously generated command signal. In this case, if a command signal that makes the damping force a strong damper is given at least one of the above judgment conditions, an output signal that makes the damping force a strong damper takes priority over a command signal that makes the damping force a weak damper based on the other judgment conditions. be done.

Next, details of the routine 300 for calculating the neutral position of the steering operating device will be explained with reference to FIG.

Steps 301 and 302 represent program steps in which the magnitude of the temporal change in the operating angle ω(1) of the steering operating device is compared with a reference value ω0 determined according to the vehicle speed V (t). Here, first, step (14): The chip 301 calculates the reference value ω0 as a function of the vehicle speed V (t). The functional formula representing the reference value ω0 is ωo=f
+ (V (t) ) −−+11, and the vehicle speed V
The relationship between (t) and the reference value ω0 can be any characteristic shown in FIG. 8 or 9. What is important is that the higher the vehicle speed V (t) is, the smaller the reference value ω0 is, thereby narrowing the allowable range for the magnitude of the temporal change in the operating angle ω(1).

In step 302, the temporal change (each operation speed) Δω of the operation angle ω(1) is calculated as follows: Δω=1ωMBMO−ω(t)1 (2)
The calculation result is compared with the reference value ω0 determined in step 301. Here, ωMEMO represents the previously input operating angle ω(1), and is stored each time the vehicle travels a predetermined distance (at step 319, which will be described later). As an initial set of this value ωMEMO,
When the operating angle ω(1) is obtained for the first time in the data input routine 200, the same value as ω(1) is set.

Now, if the temporal change Δω is larger than the reference value ω0, the program step to be executed jumps to step 307 after step 302, and if not, step 303 is executed.

Steps 303 and 304 represent steps for determining whether the acceleration θ(1) of the vehicle is larger than the reference value θ0 as one item of the magnitude of the dynamic change of the vehicle. In this case as well, in step 303, the reference value θ0 is determined as a function of the vehicle speed using the following equation.

θo=f 2 (V (t) ) --(31 In this case as well, the functional formula is set so that the reference value θ0 decreases as the vehicle speed V (t) increases. In step 304, the data input routine 200 The acceleration θ(1) obtained in step 1 is compared with the reference value θ0, and the program branches depending on the result.

In step 306, it is determined whether or not braking is being performed as another item of dynamic change in the vehicle, and the program branches depending on the result of this determination.

After all, steps 301 to 306 are a determination processing group that determines the magnitude of changes in vehicle dynamics, and among the determination items, the temporal change in the steering angle ω(1) and the acceleration θ(1) are determined. According to the present invention, for vehicle speed v(j
) is used as a reference parameter during determination. If it is determined that the dynamic change is large based on these determination results, a flag NFLA indicating this is set in step 307.
Set G to 1.

Next, in steps 309 to 313, the computer determines whether the vehicle speed V (t) is greater than a preset reference value VO (and the distance traveled during that time is greater than a preset reference value LO). In step 309, Vehicle speed V
(t) is compared with a reference value VO corresponding to, for example, 30 km/hour, and if the speed is higher than that, the content of the cumulative distance value is changed to the previously mentioned distance variable l (pulse from the vehicle speed sensor 2). data corresponding to the number of signals). This distance variable 2 is reset to 0 in the next step 311. In step 3 (17) 12, the computer calculates the distance reference value Lo as a function of the vehicle speed V (t) using the following equation.

Lo −f 3 (V (t) ) −−+41 Here, the relationship between the vehicle speed V (t) and the reference value Lo can be any characteristic shown in FIG. 10 or FIG. 11. Therefore, as the vehicle speed V (t) increases, the reference value Lo increases, and the distance that the vehicle must travel to clear the determination in step 313 increases. This means that the straight-line distance is short when driving at a relatively low speed such as in a city, and the straight-line distance is long when driving at a relatively high speed such as on an expressway. This will help you make an accurate determination.

When this condition is met, the computer executes step 3.
By checking the flag NFLAG in step 14, it is determined whether there is a large dynamic change. Steps 315 to 31 are performed only when there is no dynamic change in the determination result.
In step 7, the neutral position ωCENT of the steering operating device is calculated.

First, in step 315, it is determined whether the execution of step 315 is the first after the key switch is turned on, and only if it is the first, in step 316, the operating angle ω(1) is set to the neutral position ωCENT. Set as .

From the next time onwards, in step 317, a correction calculation for the neutral position ωCENT is executed. This calculation is performed, for example, using the following equation.

ωcENT= (a/ (a + b)) ・ωcENT
+ (b/ (a + b)) ・ωMEMO・”-15
1 Here, a and b are constants determined to satisfy the relationship a>b, for example, a=15 and b=1. In this case, it means adding 1/16 of the data ωMBMO representing the preceding operation angle ω(1) to the value obtained by subtracting 1/16 from the calculation result ωCENT up to that point. In this way, the neutral position ωCENT is gradually corrected over time.

Steps 318 to 320 define a program to be executed to periodically perform the above-mentioned arithmetic processing.

That is, in step 318, the distance integrated value is cleared to 0, and in step 319, the preceding value ωME of the operation angle ω(1) is cleared.
The operating angle ω(1) at that time is set as MO. Furthermore, the flag NFLAG is reset to 0.

Thus, the device of this embodiment monitors the degree of change in vehicle dynamics and calculates the neutral position of the steering device based on information obtained when the change in vehicle dynamics is small. In addition, when determining the degree of dynamic change, a determination point (Wo) is determined based on the traveling speed of the vehicle.

By changing θO), it is possible to adjust the speed more accurately at appropriate time intervals, whether you are driving on roads that require low speeds or roads that allow high speeds. A neutral position can be set.

Therefore, anti-roll control of the vehicle can be performed using the accurately calculated neutral position as information.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and the embodiments may be modified without departing from the scope of the claims.

Further, the present invention can also be applied as a device that applies an adjusted operation assisting force to a steering operating device.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the present invention, FIG. 2 is a block diagram of an embodiment of the present invention, FIGS. 3 and 4 are conceptual diagrams and signal time charts for explaining the steering sensor used in the embodiment, FIG. 5 is a cross-sectional view of the shock absorber used in the embodiment, and FIG. 6 is a general flowchart showing a control program for the micro combinator used in the embodiment.
FIG. 7 is a detailed flowchart of the neutral position calculation routine 300 in FIG. 6, and FIGS. 8, 9, 10, and 11 are four-charts for explaining the operation of the embodiment. DESCRIPTION OF SYMBOLS 1... Arithmetic control circuit including signal establishment means, discrimination means, and calculation means, 2... Vehicle speed sensor (second signal generation means), 3... Steering sensor (first signal generation means) , 4...braking detector (first signal generating means). Representative patent attorney Takashi Okabe (21) -7/l- ○ 16 Kaisho GO-76413 (8) Figure 6

Claims (3)

[Claims] (1) A first signal generating means that generates a first signal that changes according to the operation direction and operation movement amount of a steering controller of the vehicle, and a second signal that generates a second signal that changes according to the traveling speed of the vehicle. 12 signal generating means for establishing a third signal related to a longitudinal or lateral dynamic change of the vehicle; and a signal establishing means for establishing a third signal related to a longitudinal or lateral dynamic change of the vehicle; a determining means for determining whether or not the dynamic change is greater than a reference value determined according to the traveling speed of the vehicle; and a neutral position of the steering operating device based on the first signal when the dynamic change is smaller than the reference value as a result of this determination. A steering neutral position estimating device for a vehicle, comprising: computing means for computing. (2) The signal establishing means (1) in response to the first signal;
), the vehicle steering neutral position according to claim 1, further comprising means for calculating a temporal change in the operating angle of the steering operating device and using the calculation result as data representing the dynamic change. Estimation device. (3) Steering of a vehicle according to claim 1 or 2, wherein the signal establishing means includes means for determining the acceleration of the vehicle and using the obtained acceleration as data representing the dynamic change. Neutral position estimator.