JP3169213B2 - Moving speed detecting method and device, vehicle slip angle detecting device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control technique for stable operation of a moving body such as a vehicle.

[0002]

2. Description of the Related Art In order to stably control the operation of a vehicle, it is necessary to quantitatively detect an operation speed and a slip angle and reflect them in a control mechanism of the vehicle. The movement detecting device and the slip angle detecting device are provided as a part of the operation control mechanism of the vehicle for that purpose. Here, the slip angle can be described as follows. When the vehicle is traveling straight, if it is normal, as shown in FIG. 9A, the direction in which the wheels face and the traveling direction of the wheels match. However, when the vehicle involves skidding, the direction of the wheels and the traveling direction do not match as shown in FIG. 9B. In such a case,
The angle θ formed by the direction with respect to the traveling direction of the wheel is a slip angle (sometimes called a slip angle).

Many of the conventional slip angle detecting devices for measuring the slip angle θ employ one of the following two measurement methods. (1) The first method is a measurement value of a rotation gyro of a bearing gyro (gyro is an abbreviation of a gyroscope, the same applies hereinafter),
The slip acceleration is calculated from the difference between the measured value of the accelerometer in the lateral direction of the vehicle and the revolution angular speed calculated from the vehicle speed pulse speed, and the slip speed is obtained by integrating the slip acceleration.
Then, the slip angle θ is obtained based on the slip speed. Such a measurement method is called “azimuth angular velocity difference detection method”. (2) In the second measurement method, the forward speed and the left / right speed of the vehicle are directly measured using two ground speed sensors, and the slip angle is calculated from these measured values. Such a measurement method is called a “direct detection method”.

[0004]

However, each of the above-mentioned measuring methods has the following problems.
In the “azimuth angular velocity difference detection method”, integration of angular velocity data measured by an azimuth gyro is required, but an error occurs if the angular velocity data is integrated as it is. In addition, the drift component of the azimuth gyro greatly affects the calculation result. For this reason, a high-precision gyro sensor that can obtain zero adjustment of the azimuth gyro and its reproducibility is required, and the cost is high. Furthermore, in many cases, when slippage occurs,
The wheels fall into a locked state or an idling state, in which case the reliability of the detected slip angle is significantly reduced.

On the other hand, in the "direct measurement method", it is necessary to use two expensive ground speed sensors, and the accuracy of the measured values is greatly affected by the contamination of the ground speed sensor and the condition of the road surface.

[0006] Such a problem commonly occurs not only in vehicles but also in moving objects that perform speed control using an gyro and an accelerometer.

Accordingly, an object of the present invention is to provide an improved moving speed detection method capable of accurately detecting a moving speed even when a moving body temporarily becomes unstable. Another object of the present invention is to provide an improved slip angle detecting device that can detect an accurate slip angle by a simple method based on the moving speed detected by the above-described movement detecting method.

[0008]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a movement detection method and a movement detection device for accurately detecting the speed of a moving body. A first movement detection method according to the present invention includes a step of detecting posture data of a moving body during movement, and a step of correcting acceleration data representing acceleration applied to the moving body using the detected posture data. A step of deriving an estimated value of the moving speed of the moving body based on the corrected acceleration and the moving speed value of the moving body, and detecting a difference between the derived estimated value and the moving speed value; Outputting one of the estimated value and the moving speed value as an actual moving speed of the moving body according to a result.

In the second movement detection method, acceleration data of at least the latest one cycle among acceleration data representing acceleration of a moving object which is periodically input is held, and the held acceleration data is stored. Comparing the absolute value of the data with the absolute value of the acceleration data of the next cycle, performing a predetermined weighting process on the acceleration data having a small absolute value, and employing the weighted acceleration data as the acceleration data of the next cycle. The moving speed of the moving body is detected based on data. The weighting process is performed, for example, by setting N to the smaller one of the absolute value of the held acceleration data and the absolute value of the acceleration data in the next cycle and N to the larger one.
This is a process of dividing the sum of values multiplied by smaller M (N and M are natural numbers other than 0) by the value of N + M.

A first movement detecting device according to the present invention comprises first and second accelerometers for outputting acceleration data representing acceleration applied to first and second axes orthogonal to each other on a moving body, and the first and second accelerometers. Data correction means for periodically taking in the first and second acceleration data respectively output from the second accelerometer and correcting at least one of the acceleration data, wherein the movement of the moving object is performed based on the corrected acceleration data. An apparatus for detecting a speed, wherein the data correction means comprises: a data holding means for holding at least one of the first and second acceleration data for the latest one cycle; The absolute value is compared with the absolute value of acceleration data in the next cycle by the accelerometer, acceleration data having a smaller absolute value is subjected to a predetermined weighting process, and And having a means for holding said data holding means as the acceleration data this next cycle.

The second movement detecting device includes first to third gyros for detecting angular velocities around first to third axes orthogonal to each other on the moving body, and acceleration applied to the first and second axes. And a data correction means for correcting output data of the sensor, and a moving speed of the moving body based on the data corrected by the data correction means. An apparatus for detecting, when at least one of the first and second accelerometers and the third angular velocimeter simultaneously detect almost zero value, the data correction means detects the zero value. It is configured to clear the measured cumulative value to zero.

The third movement detecting device is a device for estimating the actual running speed of the vehicle, which is provided with a means for detecting the speed value in the forward or backward direction, and measures the lateral angular speed of the vehicle. A first gyro, a second gyro for measuring angular velocities of the vehicle in forward and reverse directions, a third gyro for measuring angular velocities of the vehicle in a turning direction, and a first acceleration for measuring accelerations in the forward and reverse directions A sensor having a second accelerometer for measuring the lateral acceleration,
Attitude detecting means for generating attitude data representing the attitude of the vehicle based on the speed value and each measurement data output from the sensor; and the generated attitude data, the speed value, the first and second accelerations. Calculating a speed estimate in the forward or backward direction of the vehicle based on the acceleration data measured by the meter, and detecting a difference between the speed estimate and the speed value, and Means for selecting one of the speed values, and outputting the selected value as an actual operating speed of the vehicle.

A slip angle detecting device according to the present invention for solving the above-mentioned other problems is an application of the above-mentioned third movement detecting device. In addition to the sensor and the attitude detecting means, the generated attitude data, Calculating a speed estimate in the forward or backward direction of the vehicle based on the speed value and the acceleration data measured by the first and second accelerometers, and calculating the speed estimate and the speed estimate by the second accelerometer; Slip speed detecting means for detecting a slip speed in the left-right direction of the vehicle based on the acceleration data and the angular speed in the turning direction;
An angle calculating unit configured to calculate the slip angle based on the estimated speed value and the detected slip speed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a slip angle detecting device mounted on a vehicle will be described below.
This will be described in detail with reference to the drawings. FIG. 1 is a configuration diagram of the slip angle detection device according to the embodiment. The slip angle detecting device 1 is attached to an instrument housing portion of a vehicle, and includes a sensor unit 10 and a data processing device 20.

The sensor unit 10 includes a roll gyro 1 for measuring the angular velocity of the vehicle in the left-right direction, that is, the degree of rolling.
1. A pitch gyro 12 for measuring an angular velocity in a forward and backward direction of a vehicle, ie, a pitch component, a yaw gyro 13 for measuring an angular velocity in a turning direction of a vehicle, ie, a yaw component, and a longitudinal accelerometer 1 for detecting acceleration of the vehicle in forward and backward directions.
4. Lateral accelerometer 1 for detecting the lateral acceleration of the vehicle
5 and these instruments 11 to 15
And a data transmission section 16 for transmitting the data to the data transmission section. The three gyros 11 to 13 are respectively installed on three-dimensional axes orthogonal to each other, and the two accelerometers 14 and 15 are installed on other axes of the three-dimensional axes except for the axis on which the yaw gyro 13 is installed. ing.

If there is an installation error of each of the instruments 11 to 15, it can be dealt with by performing a calibration process of angular velocity data and acceleration data.

The data processing device 20 is formed by the CPU 23 reading and executing a program stored in storage means such as an A / D converter 21, a pulse counter 22, a CPU (microprocessor) 23, and a ROM. Attitude detector 24, speed estimator 2
5. Slip speed detector 26, angle calculator 27, communication unit 2
It is configured to include eight functional blocks.

Output data of the sensor section 10 is input to the A / D converter 21 through a data input mechanism (not shown). The pulse counter 22 receives speed data output from a vehicle speed gauge that is provided as standard equipment in the vehicle. This speed data is pulse-shaped data (hereinafter, referred to as the speed) indicating the speed of the vehicle in the forward or reverse direction.
(Vehicle speed pulse). The processing result data of the data processing device 20 is output from the communication unit 28 to a recorder, an operation control mechanism, and the like through a data output mechanism (not shown).

The A / D converter 21 is of an integral type so that the instantaneous movement of the vehicle can be detected without missing. In order to reduce the manufacturing cost, a comparison type A / D converter may be used at any time, a low-pass filter (LPF) may be applied to the analog signal, then oversampled, and the CPU 23 may perform digital filter processing. Good.

The pulse counter 22 captures vehicle speed pulses in a predetermined calculation cycle, and can express the speed indirectly by the number of vehicle speed pulses. When speed is detected by the number of pulses, it is usually up to 10k
Although a quantization error of about m / h occurs, the quantization error peaks at the Nyquist frequency and attenuates at a rate of 6 dB / oct toward the reduction of the frequency. Can be. However, LP
If F is used, a phase delay occurs, so that phase correction is performed using acceleration data. By measuring the number of pulses by such a method, the accuracy at a low speed is superior to that in the case where speed detection is performed by measuring the time from a certain pulse to another pulse.

As shown in FIG. 2, the attitude detecting section 24 includes a differentiating circuit 241 for extracting a change component of the vehicle speed pulse, and a forward direction (or a backward direction, hereinafter, referred to as a backward direction) detected by the sensor section 10.
The adder 242 subtracts the output data of the differentiating circuit 241 from the acceleration data of “forward direction includes the backward direction” (negative addition), the LPF 243 that passes the low-frequency component of the output data of the adder 242, and the sensor unit 10.
A high-pass filter (H) that passes high frequency components of angular velocity data detected by the pitch gyro 12 output from the
A mixing unit 245 that combines the outputs of the PF) 244, the LPF 244, and the HPF 244 and outputs posture data.

For the sake of convenience, an example is shown in which acceleration data in the forward direction and angular velocity data from the pitch gyro 12 are used, but actually, lateral acceleration data and angular velocity data from the other gyros 11, 13 are used. Posture data is generated by mutually reflecting the posture data. Specifically, of the angular components output from the mixing unit 245, those based on angular velocity data of a certain axis rotation are fed back to the input stage of the attitude detection unit 24 as parameters of angular velocity data around another axis. Further, at the time of speed calculation based on certain acceleration data, correction is appropriately made using acceleration data on other axes. The detected attitude data is input to the speed estimation unit 25.

The speed estimating unit 25 calculates an estimated speed value Vx in the forward direction of the vehicle based on the vehicle speed pulse and the acceleration data measured by the lateral accelerometer 14 in addition to the attitude data. FIG. 3 shows a specific configuration example for that purpose. In other words, the sine wave component (Sin) of the posture data is
The extracted data is subtracted from the acceleration data in the left-right direction by the adder 252 (negative addition), the low-frequency component is removed by the HPF 253, and the extracted data is integrated by the integrator 254. On the other hand, after the high-frequency component of the vehicle speed pulse is removed by the LPF 256, the added value is added to the output value of the integrator 254 by the adder 255 to obtain a forward speed estimated value Vx.

Although the estimated speed Vx can be used as it is as the operating speed of the vehicle, in the present embodiment, the estimated speed Vx is output by the speed data output unit 257.
And the number of vehicle speed pulses are detected, and one of the estimated speed value and the number of vehicle speed pulses is selectively output according to the detection result. For example, when a wheel lock occurs, the difference between the two becomes large, and conversely, there is almost no difference between the two in a steady state. Therefore, a certain threshold value is determined, and the speed estimation value Vx is output when the difference exceeds the threshold value, and the vehicle speed pulse number is output when the difference is equal to or less than the threshold value. Increased accuracy. This means that the slip angle detection device 1 of the present embodiment
This means that it can also be used as a moving speed detecting device for detecting the operating speed of a vehicle. Note that the speed estimation value Vx
The acceleration data for obtaining the data may be calculated not only in the left-right direction but also in the front-rear direction.

Returning to FIG. 1, the slip speed detecting section 26 determines the right and left sides of the vehicle based on the estimated speed value Vx, the acceleration data (raw acceleration) measured by the lateral accelerometer 14, and the angular speed data measured by the yaw gyro. Sliding speed SV
This is to detect y. The specific configuration example is as shown in FIG. 4, and includes a noise cancellation processing unit 261, an adder 262, a slip angle zero determination unit 263, and a secondary HPF2.
64 and the integrator 265 to constitute the slip angle detecting section 26.

The operation of each section is as follows. The noise cancellation processing unit 261 calculates the raw acceleration G of the acceleration data.
Cancel the noise contained in y. Lateral accelerometer 14
The raw acceleration Gy from the vehicle contains a lot of noise components, and this becomes remarkable especially at the time of wheel slip. Therefore, when calculating the speed of this circling, the graph A in FIG.
It is not possible to correctly determine the sideslip angle as in
The same applies to the case where the data is simply passed through the LPF as shown in the graph B of FIG.

Therefore, a comparison with the raw acceleration Gy was previously performed using the reference Vy. Specifically, a reference SLIP acceleration was obtained by differentiating the reference Vy obtained by the ground speed sensor in advance, and this was subtracted from the centrifugal force Vw to calculate a reference acceleration, and the calculated value was compared with the raw acceleration Gy. Graph C of FIG. 8 shows the result. According to the graph C, it was found that the component inside (smaller) of the raw acceleration Gy is correct acceleration data. Therefore, in the present embodiment, in order to extract data inside the raw acceleration Gy, the noise cancellation processing unit 2
61 is provided.

The processing procedure by the noise canceling processing unit 261 is as shown in FIG. That is, the raw acceleration Gy is taken in periodically (step S101). At first, the raw acceleration Gy is held, and thereafter, it can be periodically updated to the latest one. The absolute value of the held data (previous value) and the absolute value of the next cycle of raw acceleration (current value) Gy are periodically compared (step S102). The data is subjected to a predetermined weighting process to remove noise components of the data (steps S103 and S104).

In the weighting process, the smaller of the absolute value of the previous value and the absolute value of the current value Gy is multiplied by N, and the larger one is multiplied by M smaller than N (N and M are natural numbers other than 0). Is divided by the value of N + M. Here, as a result of the simulation, data correction is performed with N being “19” and M being “1” as the most excellent numerical values.

The corrected data is adopted as corrected acceleration data (also called slip acceleration) lgy of the cycle. Then, the corrected acceleration data lgy is passed to the subsequent processing, and the existing value is updated as the previous value for the acceleration data of the next cycle (step S105). The above processing is repeated until there is no input of the raw acceleration Gy.

The corrected acceleration data lgy output from the noise canceling processing unit 261 is inverted and input to the adder 262. Data obtained by multiplying the estimated speed value Vx by the angular velocity data (yaw rate) from the yaw gyro 13 is input to the adder 262, and the two are added (the former is subtracted from the latter). . The output of the adder 262 is input to the slip angle zero determination unit 263.

The zero slip angle determination unit 263 utilizes the fact that the point at which the angular velocity (yaw rate) by the yaw gyro 13 and the acceleration data by the lateral accelerometer 14 become zero at the same time is the point at which the slip angle is zero. It is determined whether or not there is a time point (actually, a time point when the value becomes substantially zero). And both are zero value (almost zero value)
When it is determined that the offset has been obtained, the offset of the corrected acceleration data lgy and the slip angle is cleared to zero at that time. Thereby, accumulation of errors can be prevented.

The secondary HPF 264 cancels low-frequency components such as drift contained in the corrected acceleration data lgy that has passed through the slip angle determination unit 263. This is because when the corrected acceleration data lgy is simply integrated by the integrator 265, an offset error due to a yaw rate drift and an offset error of the acceleration data due to a roll inclination of the vehicle are accumulated, thereby preventing the accuracy of the slip velocity SVy from being reduced. It is provided for the purpose. HPF is second order (2
The cascade is used to converge the data. The first order is not preferable because there is a possibility of divergence. However, even if it is quadratic, depending on the set time constant τ (τ: about 1.5 seconds), the phenomenon of reversal occurs in the integration result, and especially when the time constant is short, an accurate slip angle cannot be calculated. There is. Therefore, in the present embodiment, the time constant τ is set to 15 seconds (the cutoff frequency is 0.01), the influence of the swingback is suppressed as much as possible, and the slip lateral velocity SVy is calculated. Therefore, the secondary HPF 264 can be replaced with a data fluctuation absorbing element, as long as the data fluctuation of the corrected acceleration data lgy can be converged.

Returning to FIG. 1, the angle calculator 27 calculates the slip angle based on the slip lateral speed SVy and the estimated speed value Vx. Specifically, the slip angle is calculated from arcTAN (SVy / Vx). The detected slip angle is indicated by the communication unit 2
8 to a recorder or the like.

As described above, in the slip angle detecting device 1 of the present embodiment, the acceleration data is corrected using the posture data of the running vehicle, and the vehicle is detected based on the corrected acceleration data and the vehicle speed pulse number. The operating speed is estimated, and one of the estimated speed value Vx and the vehicle speed pulse number is adopted as the actual operating speed of the vehicle according to the difference between the obtained speed estimated value Vx and the vehicle speed pulse number. Therefore, even if a wheel slip occurs, correct speed data can be displayed to the driver or transmitted to the operation control mechanism.

In addition, since the drift of the gyro, which is one of the conventional problems, is automatically corrected, the measurement accuracy at the time of occurrence of a skid can be remarkably improved as compared with the conventional method.

[0030]

As is apparent from the above description, according to the moving speed detecting method of the present invention, even if the moving body temporarily becomes unstable, the moving speed can be accurately detected. The unique effect that can be obtained is obtained. Further, according to the slip angle detecting device of the present invention, the use of the moving speed detected by the above-described movement detecting method has an effect that the slip angle can be detected at a low cost by a simple method.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a slip angle detection device to which the present invention is applied.

FIG. 2 is a functional block configuration diagram of a posture detection unit according to the embodiment.

FIG. 3 is a functional block configuration diagram of a speed estimation unit according to the embodiment.

FIG. 4 is a functional block configuration diagram of a slip speed detection unit according to the embodiment.

FIG. 5 is an explanatory diagram of a processing procedure in a slip speed detection unit.

FIG. 6 is a graph showing a relationship between a raw acceleration, an estimated skid speed, and a reference skid speed when no noise canceling processing is performed.

FIG. 7 is a graph showing a relationship between raw acceleration, an estimated skid speed, and a reference skid speed when an LPF is used in place of the noise canceling process in FIG. 6;

FIG. 8 is a graph showing a relationship between raw acceleration, an estimated sideslip speed, and a reference sideslip speed in a case where noise cancellation processing is performed in FIG. 6;

9A is a diagram illustrating a relationship between wheels and a traveling direction of a vehicle in a steady state, and FIG. 9B is a diagram illustrating a relationship between wheels and a traveling direction of a vehicle when a side slip occurs.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Slip angle detecting device 10 Sensor part 11 Roll gyro 12 Pitch gyro 13 Yaw gyro 14 Lateral accelerometer 15 Front and rear accelerometer 21 A / D converter 22 Pulse counter 23 CPU 24 Attitude detecting unit 25 Speed estimating unit 26 Slip speed detecting unit 27 Angle calculation Unit 28 Communication unit

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI // B62D 101: 00 103: 00 111: 00 133: 00 137: 00 (56) References JP-A-8-40107 (JP, A) JP-A-1-248907 (JP, A) JP-A-61-148373 (JP, A) JP-A-8-43417 (JP, A) JP-A-8-282521 (JP, A) (58) Survey Field (Int.Cl. ⁷ , DB name) G01P 7/00 G01P 15/00-15/18 G01C 19/00-19/56 G01P 3/42-3/60 G01P 9/00-9/04 B62D 6 / 00-6/06 B62D 101: 00 B62D 103: 00 B62D 111: 00 B62D 133: 00 B62D 137: 00

Claims (11)

(57) [Claims] A step of detecting posture data of the moving body during movement; a step of correcting acceleration data representing an acceleration applied to the moving body using the detected posture data; Deriving an estimated value of the moving speed of the moving object based on the moving speed value of the moving object, and detecting a difference between the derived estimated value and the moving speed value,
Outputting one of the estimated value and the moving speed value as an actual moving speed of the moving object according to a detection result. 2. The acceleration data of at least the latest one cycle among the acceleration data representing the acceleration of the moving object that is periodically input is held, and the absolute value of the held acceleration data and the next cycle are stored. Comparing the absolute value of the acceleration data, applying a predetermined weighting process to the acceleration data having a small absolute value and adopting the acceleration data as the acceleration data of the next cycle, and based on the adopted acceleration data, A moving speed detecting method comprising detecting a moving speed. 3. The weighting process includes the step of: N for the smaller of the absolute value of the held acceleration data and the absolute value of the acceleration data of the next cycle, and M for the larger one.
3. The moving speed detecting method according to claim 2, wherein a sum of values each multiplied by (N and M are natural numbers other than 0) is divided by a value of N + M. 4. A first and a second orthogonal to each other on a moving body.
First to output acceleration data representing acceleration applied to the axis
And a second accelerometer, and data correction means for periodically taking in the first and second acceleration data respectively output from the first and second accelerometers and correcting at least one of the acceleration data. An apparatus for detecting a moving speed of the moving object based on the acceleration data obtained, wherein the data correction unit holds at least one latest cycle of the first and second acceleration data. Means, comparing the absolute value of the held acceleration data with the absolute value of acceleration data in the next cycle by the accelerometer, performing a predetermined weighting process on the acceleration data having a small absolute value, and Means for causing the data holding means to hold the acceleration data in the next cycle as acceleration data. 5. A first to third orthogonal to each other on a moving body.
A sensor having first to third gyros for detecting angular velocities around an axis and first and second accelerometers for detecting accelerations applied to the first and second axes, and data correction for correcting output data of the sensors Means for detecting the moving speed of the moving body based on the data corrected by the data correcting means, wherein the data correcting means is at least one of the first and second accelerometers. When the third angular velocity meter and the third angular velocity meter simultaneously output substantially zero values, the velocity measurement device is configured to clear the accumulated value measured by the accelerometer that has detected the zero value to zero. 6. An apparatus for estimating an actual operating speed of a vehicle, comprising a means for detecting a speed value of the forward or backward direction, a first gyro for measuring an angular speed of the vehicle in a left-right direction,
A second gyro for measuring the angular velocities of the vehicle in forward and backward directions, a third gyro for measuring the angular velocities of the vehicle in the turning direction, and a first gyro for measuring the acceleration in the forward and reverse directions
An accelerometer, a sensor having a second accelerometer for measuring the acceleration in the left-right direction, and an attitude detecting means for generating attitude data representing the attitude of the vehicle based on the speed value and each measurement data output from the sensor. Calculating a speed estimation value in the forward or backward direction of the vehicle based on the generated attitude data, the speed value, and acceleration data measured by the first and second accelerometers; Means for detecting a difference between the speed value and the speed value, and selecting one of the estimated value and the speed value in accordance with the detection result, and outputting the selected value as an actual operating speed of the vehicle. A speed detecting device. 7. A device for detecting a slip angle of a vehicle, comprising a means for detecting a speed value of the forward or backward direction, wherein the first angular velocity meter measures an angular speed of the vehicle in a left-right direction.
A second gyro for measuring the angular velocities of the vehicle in forward and backward directions, a third gyro for measuring the angular velocities of the vehicle in the turning direction, and a first gyro for measuring the acceleration in the forward and reverse directions
An accelerometer, a sensor having a second accelerometer for measuring the acceleration in the left-right direction, and an attitude detecting means for generating attitude data representing the attitude of the vehicle based on the speed value and each measurement data output from the sensor. Calculating a speed estimation value in the forward or backward direction of the vehicle based on the generated attitude data, the speed value, and acceleration data measured by the first and second accelerometers; A slip speed detecting means for detecting a slip speed in the left-right direction of the vehicle based on the acceleration data measured by the second accelerometer and the angular speed in the turning direction; and the estimated speed value and the detected slip speed. And an angle calculating means for calculating the slip angle based on the slip angle. 8. The slip speed detecting means periodically takes in the measured acceleration data and holds the latest one cycle, and stores the absolute value of the held acceleration data and the acceleration data of the next cycle. The acceleration data having a small absolute value is subjected to a predetermined weighting process to remove a noise component of the acceleration data in the next cycle. Slip angle detector. 9. The slip velocity detecting means, wherein N (M, N, M) is smaller than the absolute value of the held acceleration data and the absolute value of the acceleration data of the next cycle, and smaller than N. 9. The slip angle detecting device according to claim 8, wherein the weighting process is performed by dividing a sum of values obtained by multiplying each by a natural number other than 0) by a value of N + M. 10. The slip velocity detecting means corrects the acceleration data with the derived velocity estimated value and the angular velocity in the turning direction, and corrects the corrected acceleration data by a multi-stage high-pass filter. 9. The slip angle detecting device according to claim 8, wherein the slip speed is detected by converging a variation. 11. The apparatus according to claim 7, further comprising means for clearing the slip velocity and the slip angle to zero when both the acceleration data and the angular velocity data output from the third gyro become substantially zero. 12. The slip angle detection device according to any one of items 11 to 11.