JPH05314397A - Sensor signal processor - Google Patents

Abstract

PURPOSE:To calculate an accurate yaw rate regardless of the drift amount of a yaw rate sensor in the sensor signal processor for calculating the yaw rate based on output signals from the yaw rate sensor. CONSTITUTION:A first constitution is provided with a yaw rate correction signal calculating means d1 for updating the zero point signal of the yaw rate sensor in a direction for equalizing the ratio of the values of only the plus component and the only the minus component of a steering angle and the ratio of the values of the only the plus component and only the minus component of the yaw rate when steering below prescribed steering amplitude is continued for a prescribed time under the condition of being below prescribed velocity fluctuation. The second constitution is provided with a yaw rate correction signal calculating means d2 for estimating the generated yaw rate from the steering angle, forward/backward direction velocity and vehicle characteristics and updating the output signal of the yaw rate sensor as the zero point signal when the estimated generated yaw rate is a permissible yaw rate error determined beforehand or less.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor signal processing device for a yaw rate sensor used in a vehicle motion control device or the like mounted to improve the steering stability of a vehicle.

[0002]

2. Description of the Related Art As a conventional sensor signal processing device, for example, as disclosed in Japanese Patent Laid-Open No. 57-44568, lateral acceleration or yaw rate of a vehicle is detected, and the detection signal is fed back to a rear wheel steering angle. However, there is a vehicle steering device that steers the rear wheels.

[0003]

However, in such a sensor signal processing device, since the compensation of the drift component contained in the sensor output signal for yaw rate detection is not considered at all, the drift in the sensor detection value is caused. In the case of the above-described vehicle steering system, the problem arises that the rear wheels are steered even when the vehicle is in a straight traveling state.

The present invention has been made by paying attention to the above problems, and in a sensor signal processing device for calculating a yaw rate based on an output signal from a yaw rate sensor, an accurate yaw rate sensor regardless of a drift amount of the yaw rate sensor. The common issue is to calculate the yaw rate.

[0005]

In order to solve the above-mentioned common problems, in the sensor signal processing device according to the first aspect of the present invention, steering with a predetermined steering amplitude or less is continued within a predetermined time under conditions of a predetermined speed fluctuation or less. In this case, the yaw rate sensor zero point signal is set in the same direction as the ratio between the values of only the positive component and the value of only the negative component of the steering angle and the ratio of the value of only the positive component and the value of only the negative component of the yaw rate between them. The yaw rate correction signal calculation means for updating

That is, as shown in the claim correspondence diagram of FIG. 1 (a), a steering angle detecting means a for detecting the steering angle of the vehicle, a speed detecting means b for detecting the longitudinal speed of the vehicle, and a generation of the vehicle. A yaw rate sensor c that outputs a signal according to a yaw rate, a yaw rate correction signal calculation means d1 that calculates a yaw rate correction signal from the output of the speed detection means b, the output of the steering angle detection means a, and the output of the yaw rate sensor c. And a yaw rate calculation means e for calculating a generated yaw rate from the signal output from the yaw rate sensor c and the yaw rate correction signal, in the yaw rate correction signal calculation means d1, the steering angle is set to a predetermined value. The state of being steered positively and negatively with the following steering amplitude continues for a predetermined time or longer, and the change in the speed in the front-rear direction during that time is continued. When the condition that is equal to or less than a predetermined value is satisfied, a value (Is +) calculated from the signal of only the positive component of the steering angle and a value (Is- ) And a value (ψ +) calculated from the signal of only the positive component of the yaw rate and a value (ψ−) calculated from the signal of only the negative component, and the ratio of Is + to Is− and ψ + to ψ− The yaw rate correction signal is calculated so that the ratio becomes equal.

In the sensor signal processing device according to claim 2,
The sensor signal processing device according to claim 1, wherein the yaw rate correction signal calculation means d1 is Is +, Is-, ψ +, ψ.
As the value of −, the yaw rate correction signal is calculated by using the integral value calculated from the signals of only the plus component and the minus component.

In the sensor signal processing device according to claim 3,
In the sensor signal processing device according to claim 1 or 2, the yaw rate correction signal calculation means d1 provisionally sets a plurality of yaw rate correction signals other than the yaw rate correction signal before update,
The calculation according to claim 1 or 2 is performed using each yaw rate correction signal, and the ratio of Is + to Is- and ψ + and ψ− calculated using each yaw rate correction signal.
A new yaw rate correction signal is calculated using the value of, and the yaw rate correction signal is updated.

In order to solve the above common problems, in the sensor signal processing device according to the present invention, the generated yaw rate is estimated from the steering angle, the longitudinal speed and the vehicle characteristic, and the estimated generated yaw rate is a predetermined allowable yaw rate error. In the following cases, the yaw rate correction signal calculation means for updating the output signal of the yaw rate sensor at that time as a zero point signal is provided.

That is, as shown in the claim correspondence diagram of FIG. 1 (b), a steering angle detecting means a for detecting the steering angle of the vehicle, a speed detecting means b for detecting the longitudinal speed of the vehicle, and a generation of the vehicle. A yaw rate sensor c that outputs a signal according to the yaw rate, a yaw rate correction signal calculation means d2 that calculates a yaw rate correction signal from the output of the speed detection means b, the output of the steering angle detection means a, and the output of the yaw rate sensor c. And a yaw rate calculation means e for calculating a generated yaw rate from the signal output from the yaw rate sensor c and the yaw rate correction signal. In the sensor signal processing device, the yaw rate correction signal calculation means d2 changes the generated yaw rate to the steering angle. And the above-mentioned longitudinal speed and vehicle characteristics, and the estimated generated yaw rate is less than a predetermined allowable yaw rate error. When the conditions are met that is,
The output of the yaw rate sensor is used as the yaw rate correction signal.

In the sensor signal processing device according to claim 5,
5. The sensor signal processing device according to claim 4, wherein the yaw rate correction signal calculation means d2 uses the yaw rate sensor output as the yaw rate correction signal when a condition that the longitudinal speed is equal to or lower than a predetermined value is satisfied. ..

[0012]

The operation of the present invention will be described.

When calculating the generated yaw rate, the yaw rate correction signal calculation means d1 calculates the yaw rate correction signal from the output of the speed detection means b, the output of the steering angle detection means a and the output of the yaw rate sensor c, and calculates the yaw rate. In the means e, the generated yaw rate is calculated from the signal output from the yaw rate sensor c and the yaw rate correction signal.

Of these, yaw rate correction signal calculation means d1
In the calculation process described in (1), the condition that the steering angle is positively or negatively steered with a steering amplitude equal to or less than a predetermined value continues for a predetermined time or more, and the speed fluctuation in the front-rear direction during that time is less than the predetermined value. When is satisfied, a value (Is
The value (Is
-) And a value (ψ +) calculated from the signal of only the positive component of the yaw rate and a value (ψ−) calculated from the signal of only the negative component, and the ratio of Is + to Is- and ψ + to ψ− The yaw rate correction signal is calculated so that the ratio becomes equal.

The idea is that under certain running conditions,
The steering angle detection value and the yaw rate detection value have a correspondence relationship.
Therefore, under a predetermined traveling condition, the zero point signal of the yaw rate sensor c is updated so that the positive and negative steering angle values within a predetermined time and the positive and negative yaw rate values within the predetermined time are in a mutually matching relationship. I am trying to do it.

The operation of the invention according to claim 2 will be described.

In the second aspect, the yaw rate correction signal calculating means d1 uses the integrated value calculated from the signals of only the plus component and the minus component as the value of Is +, Is-, ψ +, ψ- The signal is calculated.

The operation of the invention according to claim 3 will be described.

According to a third aspect of the present invention, the yaw rate correction signal calculating means d1 temporarily sets a plurality of yaw rate correction signals other than the yaw rate correction signal before updating, and the respective yaw rate correction signals are used. The calculation described above is performed, a new yaw rate correction signal is calculated using the ratio of Is + to Is-, and the values of ψ + and ψ− calculated using the respective yaw rate correction signals, and the yaw rate correction signal is updated. Is done.

The operation of the invention according to claim 4 will be described.

The basic calculation operation of the generated yaw rate is the same as above.

Of these, yaw rate correction signal calculation means d2
The yaw rate sensor output is calculated when the condition that the estimated yaw rate is less than a predetermined allowable yaw rate error is satisfied by estimating the generated yaw rate from the steering angle, the longitudinal speed and the vehicle characteristics. Is used as a yaw rate correction signal.

As a way of thinking, for example, no yaw rate is generated during low-speed straight traveling. Therefore, the output of the yaw rate sensor under the running condition where the yaw rate is not generated is updated as a zero point signal.

The operation of the invention of claim 5 will be described.

In the sensor signal processing device according to the fourth aspect, when the yaw rate correction signal calculating means d2 satisfies the condition that the longitudinal speed is equal to or less than a predetermined value,
The output of the yaw rate sensor is used as a yaw rate correction signal.

[0026]

Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) First, the structure will be described.

FIG. 2 shows a first invention according to claims 1 to 3.
FIG. 3 is a diagram showing a rear wheel steering angle control system to which the sensor signal processing device of the embodiment is applied, and FIG. 3 is a block diagram showing a configuration in a controller that controls a rear wheel steering angle of a vehicle.

Explaining the configuration shown in FIG. 2, the rotational movement by the steering wheel 1 is transmitted to the gearbox 3 by the column shaft 2 and converted into the linear movement of the tie rod 4. The linear motion of the tie rod 4 is converted into the swing motion of the knuckle arm 5, and the front wheels 6 are steered. At this time, the rotation angle of the column shaft 2 is transmitted to the controller 8 by the steering angle sensor 15 (corresponding to steering angle detecting means).

The vehicle 11 has a yaw rate sensor 7 for detecting a yaw rate generated by the yaw motion of the vehicle.
The controller 8 and the servo actuator 9 are installed,
A gear box 10 is connected to the actuator 9. The movement of the actuator 9 depends on the gearbox 10,
Rear wheel 12 via tie rod 14 and knuckle arm 13
Be transmitted to. Reference numeral 17 denotes an actual steering angle sensor for detecting the actual steering angle for controlling the position of the actuator 9. Reference numeral 16 denotes a vehicle speed sensor (corresponding to speed detecting means) for detecting the traveling speed of the vehicle.

When a yaw rate is generated while the vehicle is traveling, it is detected by the yaw rate sensor 7. This detection signal is
At the same time it is converted to voltage and sent to the controller 8,
The steering angle detected by the steering angle sensor 15 and the vehicle speed detected by the vehicle speed sensor 16 are sent to the controller 8. The controller 8 controls the actuator 10 based on these signals to steer the rear wheels 12.

In FIG. 3, the input yaw rate signal is the zero point voltage output from the zero point voltage calculation section 8d (corresponding to the yaw rate correction signal calculating means) in the yaw rate calculation calculating section 8a (corresponding to the yaw rate calculating means). The yaw rate is converted into the original yaw rate, and the yaw rate is input to the target rear wheel steering angle calculation unit 8b. At the same time, the signals from the vehicle speed sensor 16 and the steering angle sensor 15 are also input to the target rear wheel steering angle calculation unit 8b. The rear wheel steering angle positioning servo system 8c controls the actuator 9 so that the steering angle of the rear wheel 12 follows the target rear wheel steering angle output by the target rear wheel steering angle calculation unit 8b. Further, the zero-point voltage calculation unit 8d calculates the zero-point voltage based on the input signals from the vehicle speed sensor 16, the steering angle sensor 15, and the yaw rate sensor 7.

Next, the operation will be described.

(A) Operation of the zero point voltage calculation operation section 8d The output voltage of the yaw rate sensor 7 is Vy, and the zero point voltage before updating is Vzo. Normally, the yaw rate calculation calculator 8a
Calculates the yaw rate ψ by subtracting the zero-point voltage Vzo from the output voltage Vy of the sensor and applying the conversion constant C.

Ψ = C (Vy-Vzo) However, since the zero point voltage Vzo drifts due to changes in the operating environment, etc., the zero point voltage of the yaw rate sensor 7 is estimated by the method described below, and the above zero point is calculated. The influence of sensor drift is avoided by updating the value of voltage Vzo.

In the zero-point voltage calculation calculation unit 8d, the following integral calculation is performed every 5 ms control cycle for the zero-point calculation calculation.

Integral value of only positive component of steering angle θ (Is +) Integrated value of only negative component of steering angle θ (Is−) C · (Vy−Vzo) Integral value of only positive component (ψ0 +) C · ( Integral value (ψ0) of only the negative component of Vy-Vzo
-) C · (Vy-Vzo-α) integral value (ψ
1+) Integral value of only minus component of C · (Vy−Vzo−α) (ψ1−) Integral value of only plus component of C · (Vy−Vzo + α) (ψ
2+) Integral values of only minus component of C · (Vy−Vzo + α) (ψ2−) These integral values are reset to zero at the time of performing the zero point voltage estimation calculation of the sensor described below.

The calculation of the zero point voltage of the sensor has been performed in the past 20
This is performed when the vehicle speed fluctuation is 5 km / h or less for a second, the steering state is positive or negative, and the steering amplitude is ± 30 deg or less.

When the above conditions are not satisfied, the respective integrated values are reset to zero and the process is terminated. (B) Zero point estimation calculation The zero point estimation calculation will be described below with reference to the flowcharts of FIGS. 6 and 7. FIG. 6 is a flow chart showing the zero point voltage calculation calculation process, and FIG. 7 is a flow chart showing the integral calculation process described above.

The integral calculation process of FIG. 7 is started at regular time intervals (here, every 5 ms) to perform the integral calculation.
The contents of the integration are shown in FIG. Is +, Is-, ψ0 +, ψ0-, ψ are obtained as a result of the integration calculation in the step group 80 of FIG.
Each integrated value of 1+, ψ1-, ψ2 +, ψ2- is obtained.

Further, the maximum value θsmax and the minimum value θsmin of the steering angle θs are updated by the processing in the step group 81 in FIG. 7 at the same cycle as the integral calculation, and the vehicle speed V of the vehicle speed V is updated by the processing in the step group 82 in FIG. The maximum value Vmax and the minimum value Vmin are updated.

These values are used in the zero point voltage calculation calculation process of FIG.

The zero point voltage calculation calculation process will be described with reference to the flowchart of FIG.

First, in step 60, the value of tc is 4000
It is determined whether or not the integration calculation time has reached 20 seconds depending on whether or not (5 ms × 4000 = 20 seconds). If it has not reached 20 seconds, the process ends.

Next, in steps 61 and 62, θsmax,
Steering is positive or negative depending on the value of θsmin, and
Check if the steering amplitude is within ± 30 deg. this is,
If the steering amplitude is too large, it enters the non-linear region of the tire, so the steering amplitude is limited.

In step 63, Vmax and Vmin
Check whether the vehicle speed fluctuation is within 5 km / h based on the value of. This is because the yaw rate gain of the vehicle changes when the vehicle speed changes significantly.

If the steering angle and vehicle speed conditions in steps 61 to 63 are not satisfied, the process proceeds to step 64, in which each integrated value is reset to zero, and then step 6
5 and sets tc = 0 and ends.

On the other hand, if the conditions of the steering angle and the vehicle speed in steps 61 to 63 are satisfied, the process proceeds to step 66 and thereafter, the estimated value Vzn of the zero point voltage of the sensor is obtained, and the zero point voltage used in the yaw rate calculation is calculated. The value of Vzo is updated to Vzn. FIG. 5 is a diagram for explaining the contents of the yaw rate calculation calculation.

In step 66, Is +, Is-, ψ0 +, ψ0-, ψ1 +, ψ1-, ψ2 +, ψ2- determined by the above integral calculation.
Based on, K = Is + / Is-, L0 = ψ0 + / ψ0-, L1 = ψ1 + / ψ1-, L2 = ψ2 + / ψ2- are calculated.

In step 67, it is judged whether or not K = L0. If K = L0, it means that the zero point voltage is correct as it is. Therefore, the updating is not performed and the process ends.

Otherwise, proceed to step 68,
As shown in FIG. 5, it is divided into the case of K <L0 and the case of K> L0.

When K <L0, the true zero point voltage is Vz0
Since it is between Vzn and Vz1, a new zero point voltage Vzn is obtained using linear interpolation by Vzn = Vz0 + α (L0-K) / (L0-L1) (step 69).

When K> L0, the true zero-point voltage is Vz2
And Vz0, Vzn = Vz0 + α (K-L0) / (L2-L0) is used to obtain a new zero-point voltage Vzn using linear interpolation (step 70).

Then, in step 71, step 64
The respective integrated values are reset to zero by the same processing as the above, and the process proceeds to step 72, the zero point voltage Vzn obtained by the above calculation is updated as a new zero point voltage Vzo, and tc = 0 is set at step 65. And finish.

Next, the effect will be described.

The steering angle θs is positively and negatively steered with a steering amplitude of ± 30 deg or less for more than 20 seconds,
Further, when the condition that the variation of the vehicle speed V during that time is 5 km / h or less is satisfied, the integral value (Is +) of only the positive component and the integral value (Is of only the negative component of the steering angle θs within the 20 seconds are satisfied. -) And the integral value (ψ +) of only the positive component of the yaw rate ψ and the integral value (ψ−) of only the negative component, so that the ratio of Is + to Is- is equal to the ratio of ψ + to ψ−. Since the zero point voltage Vzo of the sensor 7 is updated, the correct yaw rate ψ can be calculated regardless of the drift amount of the yaw rate sensor 7.

As a result, in the rear wheel steering angle control using the yaw rate ψ as the control information, the fact that the rear wheel is steered during straight traveling due to drift of the yaw rate detection value is eliminated, and a high rear wheel steering angle control is achieved. Accuracy can be secured.

In the first embodiment, the calculation is performed by providing three temporary zero points used for the integral calculation of the yaw rate. However, a larger number of temporary zero points are provided and the most appropriate value is newly updated. It is also possible to use it as a zero point.

Further, instead of the integral calculation used in this embodiment, another arithmetic method having the same meaning as the integral (for example,
Of course, it is also possible to use the average value).

As in the case of the second embodiment, the yaw rate zero point is updated by limiting the amount of update per unit time so that the old zero point can be smoothly updated to the new zero point. You can

This sensor signal processing device is similar to the following second embodiment, but in addition to the rear wheel steering angle control system shown in the present embodiment, a braking force control system (right and left) using yaw rate as control information is used. The present invention can be applied to other control systems such as applying a braking force difference to a wheel) and a driving force control system (applying a driving force difference to left and right wheels).

(Second Embodiment) This second embodiment is an example of a sensor signal processing device corresponding to the invention described in claims 4 and 5.

Since the structure is the same as that of the first embodiment shown in FIGS. 2 and 3, illustration and description thereof will be omitted.

The operation will be described.

(A) Function of the zero point voltage calculation operation section 8d The output voltage of the yaw rate sensor 7 is Vy, and the zero point voltage before updating is Vzo. Normally, the yaw rate calculation calculator 8a
Calculates the yaw rate ψ by subtracting the zero-point voltage Vzo from the output voltage Vy of the sensor and applying the conversion constant K.

Ψ = K (Vy-Vzo) However, the zero point voltage Vzo drifts due to changes in the operating environment, etc. Therefore, the zero point voltage of the yaw rate sensor 7 is estimated by the following method, and the zero point The influence of sensor drift is avoided by updating the value of voltage Vzo.

The basic idea is to update the value of Vzo using the output voltage Vy in the state where the yaw rate is not generated as the zero point voltage of the yaw rate sensor 7. Here, when the generated yaw rate is equal to or less than the allowable yaw rate error, it is determined that the yaw rate is not generated.

The yaw rate ψ'generated at an extremely low speed is expressed by the following equation.

Ψ ′ = Vθ / NL where θ is the steering angle, N is the steer gear ratio, and L is the wheel base length.

When the allowable yaw rate error is ψ'm and the above equation is rewritten, the following equation is obtained.

V = NLψ'm / | θ | Here, the vehicle speed V is a speed at which the allowable yaw rate error ψ'm is generated. Therefore, when the vehicle speed is V or less, the generated yaw rate is less than the allowable yaw rate error. V is measured from the pulse signal of the vehicle speed sensor 16.

Here, when the distance advanced to the vehicle speed pulse interval is x, the above equation is expressed by the following equation.

NLψ′m / | θ | = x / tr Here, tr is the time between pulses when the vehicle speed pulse corresponding to the V is generated. When the above formula is transformed,
The following equation is obtained.

Tr = x | θ | / NLψ'm For example, as an example of specifications of an actual vehicle, x = 0.78 (m), L
= 3.3 (m), N = 15.3, ψ'm = 1 (deg / sec), tr = 0.015 | θ | Therefore, tr is determined by the steering angle θ. If the vehicle speed pulse is not generated even if this tr is exceeded, the generated yaw rate is less than the allowable yaw rate error, and the zero point voltage V
Update zo.

(B) Zero Point Estimation Calculation The zero point estimation calculation will be described below with reference to the flowcharts of FIGS. 9 and 10. FIG. 9 is a flow chart showing the zero point voltage calculation calculation process, and FIG. 10 is a flow chart showing the calculation process of the time tr between pulses when the vehicle speed pulse described above is generated.

The tr calculation process of FIG. 10 is started at fixed time intervals (here, every 5 ms), and the time tr is calculated. First, in steps 100 to 102, the time tr is calculated.

Then, in step 103, it is determined whether or not a vehicle speed pulse is generated (Vp = 1).

If the vehicle speed pulse is generated, the process proceeds to steps 104 to 106 to reset all the conditions.

When the vehicle speed pulse is not generated, the routine proceeds to step 107, where the count-up is performed. If the steering angle θ increases during counting, the time tr is updated and the most severe condition is set.

The zero point voltage calculation processing will be described with reference to the flowchart of FIG.

First, at step 90, the vehicle speed V is 5 km / h.
It is determined whether or not If the speed is 5 km / h or more, the process ends.

In step 91, it is determined whether tc = tr. If tc is less than tr, terminate.

In step 92, when tc = tr, C is incremented. C is the number of times tc between two vehicle speed pulses
This is a counter that counts whether or not = tr.

As shown in FIG. 8, when C = 1, only the output voltage Vy is measured and the zero-point voltage Vzo is not updated (step 93 → step 94).

When C> 1, the output voltage Vy measured last time
The zero point voltage Vzo is updated with the new zero point as the new zero point, and the output voltage Vy at that time is measured (step 93 →
Step 95 → step 94).

Thereafter, tc is reset at step 96,
In step 97, θs is reset and the process ends.

Next, the effect will be described.

When the vehicle speed V is 5 km / h or less, the generated yaw rate is estimated from the steering angle θ, the vehicle speed V and the vehicle characteristics, and the estimated generated yaw rate ψ'is less than a predetermined allowable yaw rate error ψ'm. When the condition that is
The output voltage Vy from the yaw rate sensor 7 is set to the zero point voltage Vy.
Since it is updated as zo, the correct yaw rate ψ can be calculated regardless of the drift amount of the yaw rate sensor 7.

As a result, in the rear wheel steering angle control using the yaw rate ψ as the control information, the fact that the rear wheel is steered during straight traveling due to the drift of the detected yaw rate is eliminated, and the high rear wheel steering angle control is performed. Accuracy can be secured.

In the second embodiment, the zero-point voltage Vzo is not updated when C = 1, but this is taken into consideration in consideration of the acceleration / deceleration of the vehicle between two vehicle speed pulses. This is to determine an accurate zero point voltage. Even when the output voltage Vy when C = 1 is set as a new zero point and the zero point voltage Vzo is updated, the zero point voltage can be determined within the allowable yaw rate error.

[0091]

According to the first aspect of the present invention, in the sensor signal processing device for calculating the yaw rate based on the output signal from the yaw rate sensor, the steering with the predetermined steering amplitude or less is the predetermined speed fluctuation or less. If the steering angle continues for a predetermined time under the condition of, the ratio of the value of only the positive component and the value of the negative component of the steering angle during that period is made equal to the ratio of the value of only the positive component of the yaw rate and the value of only the negative component. Since the yaw rate correction signal calculating means for updating the zero point signal of the yaw rate sensor in the direction is provided, it is possible to obtain an effect that an accurate yaw rate can be calculated regardless of the drift amount of the yaw rate sensor.

According to a second aspect of the present invention, in the sensor signal processing apparatus according to the first aspect, the yaw rate correction signal calculating means has a plus component as a value of Is +, Is-, ψ +, ψ-. Since the yaw rate correction signal is calculated using the integrated value calculated from the signal of only the minus component, the yaw rate correction is based on the plus component integrated value and the minus component integrated value, and a more accurate yaw rate can be calculated. ..

According to a third aspect of the present invention, in the sensor signal processing device according to the first and second aspects, the yaw rate correction signal calculation means temporarily outputs a plurality of yaw rate correction signals other than the yaw rate correction signal before updating. The yaw rate correction signal is set and the calculation according to claim 1 or 2 is performed using each yaw rate correction signal, and the ratio of Is + to Is- and the values of ψ + and ψ− calculated using each yaw rate correction signal are used. Since a new yaw rate correction signal is calculated and the yaw rate correction signal is updated, the accuracy of the reference zero point is increased, so that a more accurate yaw rate can be calculated.

According to the fourth aspect of the present invention, in the sensor signal processing device for calculating the yaw rate based on the output signal from the yaw rate sensor, the generated yaw rate is estimated from the steering angle, the longitudinal speed and the vehicle characteristic. , If the estimated generated yaw rate is less than or equal to a predetermined allowable yaw rate error, the yaw rate correction signal calculation means for updating the output signal of the yaw rate sensor at that time as a zero point signal is provided, so that it is accurate regardless of the drift amount of the yaw rate sensor. The effect that it is possible to calculate a different yaw rate is obtained.

According to a fifth aspect of the present invention, in the sensor signal processing apparatus according to the fourth aspect, the yaw rate correction signal calculating means satisfies the condition that the longitudinal velocity is equal to or less than a predetermined value, Since the yaw rate sensor output is used as the yaw rate correction signal, the sampled yaw rate sensor output is stable, and a more accurate yaw rate can be calculated.

[Brief description of drawings]

FIG. 1 is a claim correspondence diagram showing a sensor signal processing device of the present invention.

FIG. 2 is an overall view showing a rear wheel steering angle control system to which the sensor signal processing device of the embodiment is applied.

FIG. 3 is a block diagram showing an internal configuration of a controller of the system of the embodiment.

FIG. 4 is a diagram illustrating the content of each integral calculation of a steering angle and a yaw rate used in the yaw rate calculation calculation of the first embodiment.

FIG. 5 is a diagram illustrating a method of obtaining a zero-point voltage in a yaw rate calculation calculation according to the first embodiment.

FIG. 6 is a flowchart showing the flow of zero-point voltage calculation processing in the device of the first embodiment.

FIG. 7 is a flowchart showing a flow of calculation processing of an integrated value and the like in the device of the first embodiment.

FIG. 8 is a vehicle speed pulse characteristic diagram illustrating the update timing of the zero-point voltage in the second embodiment device.

FIG. 9 is a flowchart showing the flow of zero-point voltage calculation processing in the device of the second embodiment.

FIG. 10 is a flow chart showing a flow of arithmetic processing of tr and tc in the device of the second embodiment.

[Explanation of symbols]

 a steering angle detection means b speed detection means c yaw rate sensor d1 yaw rate correction signal calculation means d2 yaw rate correction signal calculation means e yaw rate calculation means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical display location B62D 113: 00 137: 00 (72) Inventor Junji Tsutsumi 2 Takaracho, Kanagawa-ku, Kanagawa Prefecture Nissan Motor Co., Ltd. Within the corporation

Claims (5)

[Claims] 1. A steering angle detecting means for detecting a steering angle of a vehicle, a speed detecting means for detecting a longitudinal speed of the vehicle, a yaw rate sensor for outputting a signal according to a yaw rate generated by the vehicle, and the speed detecting means. A yaw rate correction signal calculation means for calculating a yaw rate correction signal from the output of the steering angle detection means and the output of the yaw rate sensor,
In a sensor signal processing device comprising a yaw rate calculation means for calculating a generated yaw rate from a signal output from the yaw rate sensor and the yaw rate correction signal, the yaw rate correction signal calculation means has a steering amplitude in which the steering angle is a predetermined value or less. When the condition that the positive and negative steering is continued for a predetermined time or more and the fluctuation of the speed in the front-rear direction during that time is less than a predetermined value, the plus component of the steering angle within the predetermined time is satisfied. Value (Is +) calculated from the signal of only the negative component and a value (Is-) calculated from the signal of only the negative component, and a value (ψ +) calculated from the signal of only the positive component of the yaw rate and the signal of only the negative component Calculate the value (ψ−) calculated from
A sensor signal processing device, wherein a yaw rate correction signal is calculated so that a ratio of Is- and a ratio of ψ + to ψ- become equal. 2. The sensor signal processing device according to claim 1, wherein the yaw rate correction signal calculation means uses an integrated value of only a positive component of the steering angle within the predetermined time as the value of Is +, and the value of Is− As the value, the integrated value of only the minus component of the steering angle within the predetermined time is used, as the value of ψ +, the integrated value of only the positive component of the yaw rate within the predetermined time is used, and as the value of ψ− within the predetermined time. 2. A sensor signal processing device, characterized in that it is means for using an integrated value of only the negative component of the yaw rate. 3. The sensor signal processing device according to claim 1, wherein the yaw rate correction signal calculation means temporarily sets a plurality of yaw rate correction signals other than the yaw rate correction signal before update, and each yaw rate correction signal is set. The calculation according to claim 1 or 2 is performed by using the ratio of Is + to Is-, and
A new yaw rate correction signal is calculated using the values of ψ + and ψ− calculated using the respective yaw rate correction signals,
A sensor signal processing device characterized by updating a yaw rate correction signal. 4. A steering angle detecting means for detecting a steering angle of a vehicle, a speed detecting means for detecting a longitudinal speed of the vehicle, a yaw rate sensor for outputting a signal according to a yaw rate generated by the vehicle, and the speed detecting means. A yaw rate correction signal calculation means for calculating a yaw rate correction signal from the output of the steering angle detection means and the output of the yaw rate sensor,
In a sensor signal processing device comprising a yaw rate calculating means for calculating a generated yaw rate from a signal output from the yaw rate sensor and the yaw rate correction signal, the yaw rate correction signal calculating means may change the generated yaw rate to the steering angle and the longitudinal speed. And a vehicle characteristic, and when the condition that the estimated generated yaw rate is equal to or less than a predetermined allowable yaw rate error is satisfied, the yaw rate sensor output is used as the yaw rate correction signal. apparatus. 5. The sensor signal processing device according to claim 4, wherein the yaw rate correction signal calculation means outputs the yaw rate sensor output to the yaw rate sensor when a condition that the longitudinal speed is equal to or less than a predetermined value is satisfied. A sensor signal processing device characterized by using a correction signal.