JP2018036155A - Controller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To heighten the accuracy of vehicle speed information based on the output signal of a wheel speed sensor in a low speed region at which a vehicle slows down.SOLUTION: Provided is a controller which, in a vehicle provided, in each of a plurality of wheels of the vehicle, with a wheel speed sensor for detecting the revolution speed of the wheel, compares the output signal of a wheel speed sensor ancillary to an object wheel with the output signals of wheel speed sensors ancillary to other wheels, or compares a change amount per unit time of the revolution speed of the object wheel obtained by referring to the output signal of the wheel speed sensor ancillary to the object wheel with a threshold, thereby determining whether or not disturbance is mixed in the output signal of the wheel speed sensor ancillary to the object wheel; and outputs the values of revolution speeds of the wheels based on the output signal of the wheel speed sensor that was determined to have no disturbance mixed therein, or outputs the result of determination of whether or not disturbance is mixed in the output signals of wheel speed sensors.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a vehicle control device in which each of a plurality of wheels provided in a vehicle is provided with a wheel speed sensor that detects the rotational speed of the wheel.

  The wheel speed sensor is provided with, for example, a plurality of N-pole and S-pole magnetic poles alternately along the outer periphery of a rotating body that rotates with the wheel, and a magnetic detection element such as a magnetoresistive element or a Hall element in the vicinity of the outer periphery of the rotating body. Is arranged. When the wheel rotates, the magnetic fluctuation due to the movement of the magnetic pole accompanying the rotation is detected via the magnetic detection element and output as a pulse signal. By counting the number of pulses per unit time, the rotational speed of the wheel can be obtained, and the vehicle speed, that is, the moving speed of the vehicle can be derived (refer to the following patent document).

  The accuracy of detection of the vehicle speed with reference to the output signal of the wheel speed sensor decreases in a low speed range where the vehicle slows down at a speed of 10 km or less. In the low-speed range, the number of pulses of the signal output from the wheel speed sensor decreases, ignoring the discrepancy between the vehicle speed and the number of pulses caused by the output of an invalid pulse due to slip on the road surface of the wheel or vibration at the location where the wheel speed sensor is installed. Because it is impossible. Therefore, conventionally, when the vehicle speed obtained by referring to the output signal of the wheel speed sensor is in the low speed range, the vehicle speed is uniformly regarded as zero.

  On the other hand, recently, an attempt has been made to mount a system that supports driving at the time of parking in a vehicle. The parking assistance system needs information on the vehicle speed or the rotational speed of the wheel in the extremely low speed range, and information with high accuracy.

JP2015-148495A

  An object of the present invention is to improve the accuracy of vehicle speed information based on an output signal of a wheel speed sensor in a low speed range where the vehicle travels slowly.

  In the present invention, in a vehicle in which a wheel speed sensor for detecting the rotational speed of the wheel is attached to each of a plurality of wheels included in the vehicle, the output signal of the wheel speed sensor associated with the target wheel and the other wheels. The amount of change per unit time of the rotational speed of the target wheel obtained by comparing with the output signal of the wheel speed sensor attached thereto or by referring to the output signal of the wheel speed sensor attached to the target wheel Is compared with the threshold value to determine whether disturbance is mixed in the output signal of the wheel speed sensor associated with the target wheel, and based on the output signal of the wheel speed sensor determined to be free of disturbance. The control device is configured to output the value of the rotational speed of the wheel, or to output a determination result as to whether or not a disturbance is mixed in the output signal of the wheel speed sensor.

  ADVANTAGE OF THE INVENTION According to this invention, the accuracy of the information of the vehicle speed based on the output signal of a wheel speed sensor can be improved in the low speed area where a vehicle slows down.

The block diagram which shows the structure of the control apparatus of one Embodiment of this invention. The flowchart which shows the example of the procedure of the process which the control apparatus of the embodiment performs. The flowchart which shows the example of the procedure of the process which the control apparatus of the embodiment performs. The flowchart which shows the example of the procedure of the process which the control apparatus of the embodiment performs.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the configuration of the vehicle control device 1 of the present embodiment. The wheel speed sensors 21, 22, 23, and 24 attached to the respective wheels FR, RR, FL, and RL of the vehicle are known ones used for ABS (Antilock Break System). Each wheel speed sensor 21, 22, 23, 24 outputs a number of pulses proportional to the amount of rotation (rotation angle or number of rotations) of the target wheels FR, RR, FL, RL. If the number of pulses per unit time is counted, the rotational speeds of the target wheels FR, RR, FL, and RL can be obtained. As a result, it is possible to derive the vehicle speed.

  The control device 1 of the present embodiment is mainly composed of an ECU (Electronic Control Unit) which is a microcomputer system having a processor, a main memory, an auxiliary storage device (flash memory, etc.), an input / output interface, and the like. The ECU 1 may be the same as a so-called ABS-ECU that controls the ABS.

  A program to be executed by the processor is stored in advance in the auxiliary storage device of the ECU 1. In executing the program, the program is read from the auxiliary storage device into the main memory and decoded by the processor. The ECU 1 serving as the control apparatus follows the program according to the right front wheel disturbance determination unit 11, the right rear wheel disturbance determination unit 12, the left front wheel disturbance determination unit 13, the left rear wheel disturbance determination unit 14, and the right wheel rotation speed output unit 15 shown in FIG. And the function as the left wheel rotation speed output unit 16.

  The right front wheel disturbance determination unit 11 determines whether disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR of the vehicle. Disturbance means that the number of pulses output from the wheel speed sensors 21, 22, 23, 24 increases or decreases from the number of pulses that matches the actual vehicle speed. As a cause of the disturbance, the wheel speed sensors 21, 22, 23, and 24 are caused by slipping of the wheels FR, RR, FL, and RL with respect to the road surface, and vibrations at the positions where the wheel speed sensors 21, 22, 23, and 24 are installed. Output an unjustified pulse. The right rear wheel disturbance determination unit 12 determines whether a disturbance is mixed in the output signal of the wheel speed sensor 22 attached to the right rear wheel RR of the vehicle. The left front wheel disturbance determination unit 13 determines whether a disturbance is mixed in the output signal of the wheel speed sensor 23 attached to the left front wheel FL of the vehicle. And the left rear wheel disturbance determination part 14 determines whether the disturbance is mixed in the output signal of the wheel speed sensor 24 accompanying the left rear wheel RL of a vehicle.

A method for determining whether or not a disturbance is mixed in the output signals of the wheel speed sensors 21, 22, 23, and 24 by the disturbance determination units 11, 12, 13, and 14 will be specifically described. Whether or not disturbance is mixed in the output signals of the wheel speed sensors 21, 22, 23, and 24 is determined by the following three conditions (I), (II), and (III):
(I) The absolute value of the difference in the number of pulses output by each of the three wheel speed sensors associated with the three wheels including the target wheel within the latest unit time (for example, 50 milliseconds) is a predetermined threshold value. Whether or not it is below (If it is within the range, the disturbance is not mixed in. If it is not within the range, the disturbance is mixed in)
For example, in order to determine whether disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR, the number of pulses output by the wheel speed sensor 21 within the latest unit time, right The number of pulses output by the wheel speed sensor 22 associated with the rear wheel RR within the same unit time and the number of pulses output by the wheel speed sensor 23 associated with the left front wheel FL within the same unit time are counted. Then, the absolute value of the difference obtained by subtracting the number of pulses output from the wheel speed sensor 22 attached to the right rear wheel RR from the number of pulses output from the wheel speed sensor 21 attached to the right front wheel FR is compared with a threshold value. In addition, the absolute value of the difference obtained by subtracting the number of pulses output from the wheel speed sensor 23 attached to the left front wheel FL from the number of pulses output from the wheel speed sensor 21 attached to the right front wheel FR is compared with a threshold value. If the absolute value of any difference is equal to or less than the threshold value, it is determined that no disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR. In contrast, if the absolute value of any difference exceeds the threshold value, it is determined that a disturbance is mixed in the output signal of the wheel speed sensor 21.
Alternatively, the number of pulses output by the wheel speed sensor 21 within the latest unit time, the number of pulses output by the wheel speed sensor 22 associated with the right rear wheel RR within the unit time, and the wheel associated with the left front wheel FL You may make it compare the value of the difference which subtracted the minimum thing from the largest thing among the number of the pulses which the speed sensor 23 output within the same unit time with a threshold value. If the difference value is less than or equal to the threshold value, it is determined that no disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR. In contrast, if the difference value exceeds the threshold value, it is determined that a disturbance is mixed in the output signal of the wheel speed sensor 21.

(II) The number of pulses output by the wheel speed sensor associated with the target wheel within the most recent unit time (for example, 50 milliseconds up to the current time from the time 50 milliseconds back from the current time), and past units The absolute value of the difference from the number of pulses output within a time (for example, 50 milliseconds from the time point that is 100 milliseconds from the current time point to the time point that is 50 milliseconds from the current time point) falls within a predetermined threshold value. Whether or not (disturbance is not mixed if it is settled, disturbance is mixed if not settled)
For example, in order to determine whether or not disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR, the number of pulses output by the wheel speed sensor 21 within the latest unit time, The number of pulses output by the wheel speed sensor 21 within the past unit time is counted. Then, a difference value obtained by subtracting a smaller one from the larger number of the two pulses is compared with a threshold value. If the difference value is less than or equal to the threshold value, it is determined that no disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR. In contrast, if the difference value exceeds the threshold value, it is determined that a disturbance is mixed in the output signal of the wheel speed sensor 21.

(III) When the number of pulses output by the wheel speed sensor associated with any one of the wheels other than the target wheel within the most recent unit time (for example, 100 milliseconds) is 0, the wheel speed sensor is associated with the target wheel. Whether the number of pulses output by the wheel speed sensor within the same unit time is within a predetermined threshold or not (disturbance is not mixed if it is, and disturbance is mixed if it is not)
For example, in order to determine whether disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR, the number of pulses output by the wheel speed sensor 21 within the latest unit time, right The number of pulses output by the wheel speed sensor 22 associated with the rear wheel RR within the same unit time, the number of pulses output by the wheel speed sensor 23 associated with the left front wheel FL within the same unit time, and associated with the left rear wheel RL The number of pulses output by the wheel speed sensor 24 within the same unit time is counted. In addition, when the number of pulses output by the wheel speed sensors 22, 23, 24 associated with any of the wheels RR, FL, RL other than the right wheel FR within the same unit time is 0, the right wheel FR The number of pulses output by the wheel speed sensor 21 attached to the same unit time within the same unit time is compared with a threshold value. If the number of pulses is equal to or less than the threshold value, it is determined that no disturbance is included in the output signal of the wheel speed sensor 21 associated with the right front wheel FR, and if the number of pulses exceeds the threshold value, It is determined that a disturbance is mixed in the output signal of the wheel speed sensor 21.

  Examining the success or failure of the above conditions (I) and (III) depends on the output signals of the wheel speed sensors 21, 22, 23, 24 associated with the target wheels FR, RR, FL, RL and the other wheels FR. , RR, FL, RL means that the output signals of the wheel speed sensors 21, 22, 23, 24 attached to RL are compared. Further, the examination of the success / failure of the condition (II) is based on the target obtained by referring to the output signals of the wheel speed sensors 21, 22, 23, 24 attached to the target wheels FR, RR, FL, RL. This means that the amount of change per unit time of the rotational speed of the wheels FR, RR, FL, RL is compared with a threshold value.

  The right wheel rotational speed output unit 15 outputs information on the rotational speed of the right front wheel FR based on the output signal of the wheel speed sensor 21 attached to the right front wheel FR. However, as will be described later, when disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR, the right rear wheel based on the output signal of the wheel speed sensor 22 associated with the right rear wheel RR. Information on the rotational speed of the wheel RR may be output. Further, the left wheel rotation speed output unit 16 outputs information on the rotation speed of the left front wheel FL based on the output signal of the wheel speed sensor 23 attached to the left front wheel FL. However, when disturbance is mixed in the output signal of the wheel speed sensor 23 associated with the left front wheel FL, the rotational speed of the left rear wheel RL based on the output signal of the wheel speed sensor 24 associated with the left rear wheel RL. May be output.

  FIG. 2 to FIG. 4 show a procedure example of processing executed by the ECU 1 according to the program. First, the right front wheel disturbance determination unit 11 examines whether the above conditions (I), (II), and (III) are successful for the right front wheel FR (steps S1 to S3). When the disturbance is mixed by at least one of the conditions (I), (II), and (III), the output signal of the wheel speed sensor 21 associated with the right front wheel FR is output. It is determined that a disturbance is mixed (step S4). Otherwise, it is determined that no disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR (step S5).

  Next, the right rear wheel disturbance determination unit 12 examines whether the conditions (I), (II), and (III) are successful for the right rear wheel RR (steps S6 to S8). When the disturbance is mixed due to at least one of the conditions (I), (II), and (III), the output signal of the wheel speed sensor 22 associated with the right rear wheel RR. It is determined that disturbance is mixed in (step S9). Otherwise, it is determined that no disturbance is mixed in the output signal of the wheel speed sensor 22 attached to the right rear wheel RR (step S10).

  Further, the left front wheel disturbance determination unit 13 examines whether the conditions (I), (II), and (III) are successful for the left front wheel FL (steps S11 to S13). When the disturbance is mixed due to at least one of the conditions (I), (II), and (III), the output signal of the wheel speed sensor 23 associated with the left front wheel FL is It is determined that a disturbance is mixed (step S14). Otherwise, it is determined that no disturbance is mixed in the output signal of the wheel speed sensor 23 associated with the left front wheel FL (step S15).

  Further, the left rear wheel disturbance determination unit 14 examines the success or failure of the conditions (I), (II), and (III) for the left rear wheel RL (steps S16 to S18). When the disturbance is mixed due to at least one of the conditions (I), (II), and (III), the output signal of the wheel speed sensor 24 associated with the left rear wheel RL. It is determined that a disturbance is mixed in (step S19). Otherwise, it is determined that no disturbance is mixed in the output signal of the wheel speed sensor 24 attached to the left rear wheel RL (step S20).

  Therefore, the right wheel rotation speed output unit 15 refers to the output signal of the wheel speed sensor 21 attached to the right front wheel FR according to the determination results by the right front wheel disturbance determination unit 11 and the right rear wheel disturbance determination unit 12. Alternatively, it is selected whether to refer to the output signal of the wheel speed sensor 22 associated with the right rear wheel RR. That is, if no disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR (step S21), the wheel speed sensor 21 associated with the right front wheel FR is in the nearest unit time (for example, 50 milliseconds). ) Is output as a value suggesting the rotational speed of the right front wheel FR and thus the vehicle speed (step S22). At the same time, information indicating a determination result that no disturbance is mixed in the output signal of the wheel speed sensor 21 (which may be reset of a 1-bit flag) is also output.

  On the other hand, if the disturbance is mixed in the output signal of the wheel speed sensor 21 associated with the right front wheel FR, but the disturbance is not mixed in the output signal of the wheel speed sensor 22 associated with the right rear wheel RR ( In step S23), the number of pulses output by the wheel speed sensor 22 associated with the right rear wheel RR within the latest unit time (50 milliseconds) is output as an alternative value indicating the rotational speed of the right front wheel FR (step S23). S24). At the same time, information indicating a determination result that no disturbance is mixed in the output signal of the wheel speed sensor 22 (which may be reset of a 1-bit flag) is also output. The output of the front wheel side sensors 21 and 23 is given priority because the front wheels FR and FL, which are steered wheels, draw more than the rear wheels RR and RL when driving a vehicle for parking. This is because the radius of the locus (turning radius) is large and the amount of rotation or the rotation speed is also large.

  If disturbance is also present in the output signal of the wheel speed sensor 21 associated with the right front wheel FR and the output signal of the wheel speed sensor 22 associated with the right rear wheel RR, the wheel speed sensor associated with the right front wheel FR. The number of pulses 21 output within the latest unit time (50 milliseconds) is output as a value suggesting the rotational speed of the right front wheel FR (step S25). However, since an error is expected to be mixed in the value of the rotational speed, information indicating a determination result that a disturbance is mixed in the output signal of the wheel speed sensor 21 (with a 1-bit flag set) May also be output.

  In steps S22, S24, and S25, the value of the rotational speed of the right front wheel FR and the information of the determination result are written in the memory or auxiliary storage device of the ECU 1, and / or via an in-vehicle network such as CAN (Controller Area Network). The data is transmitted to other ECUs that are communicably connected, for example, an ECU that controls an internal combustion engine or an electric motor mounted as a vehicle drive source, or an ECU that constitutes a parking assistance or other driving assistance system.

  Similarly, the left wheel rotation speed output unit 16 refers to the output signal of the wheel speed sensor 23 attached to the left front wheel FL according to the determination results by the left front wheel disturbance determination unit 13 and the left rear wheel disturbance determination unit 14, or Alternatively, it is selected whether to refer to the output signal of the wheel speed sensor 24 attached to the left rear wheel RL. That is, if there is no disturbance in the output signal of the wheel speed sensor 23 associated with the left front wheel FL (step S26), the wheel speed sensor 23 associated with the left front wheel FL is within the latest unit time (50 milliseconds). The number of pulses output to is output as a value suggesting the rotational speed of the left front wheel FL and thus the vehicle speed (step S27). At the same time, information indicating the determination result that no disturbance is mixed in the output signal of the wheel speed sensor 23 (which may be reset of a 1-bit flag) is also output.

  On the other hand, if the disturbance is mixed in the output signal of the wheel speed sensor 23 associated with the left front wheel FL, but the disturbance is not mixed in the output signal of the wheel speed sensor 24 associated with the left rear wheel RL ( In step S28, the number of pulses output by the wheel speed sensor 24 associated with the left rear wheel RL within the latest unit time (50 milliseconds) is output as an alternative value indicating the rotational speed of the left front wheel FL (step S28). S29). At the same time, information indicating the determination result that no disturbance is mixed in the output signal of the wheel speed sensor 24 (which may be reset of a 1-bit flag) is also output.

  If disturbance is mixed in the output signal of the wheel speed sensor 23 associated with the left front wheel FL and the output signal of the wheel speed sensor 24 associated with the left rear wheel RL, the wheel speed sensor associated with the left front wheel FL. The number of pulses 23 output within the latest unit time (50 milliseconds) is output as a value suggesting the rotational speed of the left front wheel FL (step S30). However, since it is expected that an error is mixed in the value of the rotational speed, information indicating a determination result that a disturbance is mixed in the output signal of the wheel speed sensor 23 (with a 1-bit flag set). May also be output.

  In steps S27, S29, and S30, the value of the rotational speed of the left front wheel FL and information on the determination result are written in the memory or auxiliary storage device of the ECU 1 and / or connected via an in-vehicle network such as CAN. To other ECUs.

  The ECU 1 repeatedly executes the above steps S1 to S30 every unit time (for example, 50 milliseconds).

  Incidentally, the above condition (III) tries to detect an event in which the wheel speed sensors 21, 22, 23, and 24 output a pulse signal due to a disturbance even though the vehicle is actually stopped. Is. Therefore, the unit time length (100 milliseconds) in the examination of success / failure of the condition (III) is the length of the unit time in the examination of success / failure of the conditions (I) and (II) and the repetition cycle of steps S1 to S30. It is preferable to set longer than (both are 50 milliseconds).

  In the present embodiment, wheel speed sensors 21, 22, 23, and 24 that detect the rotational speed of the wheels FR, RR, FL, and RL are attached to each of the plurality of wheels FR, RR, FL, and RL included in the vehicle. Output signals of the wheel speed sensors 21, 22, 23, 24 associated with the target wheels FR, RR, FL, RL and the wheel speed sensors 21, associated with the other wheels FR, RR, FL, RL, The wheel speed sensors 21, 22, 23, 24 associated with the target wheels FR, RR, FL, RL are compared with the output signals of 22, 23, 24 (conditions (I) and (III)). By comparing the amount of change per unit time of the rotational speed of the target wheels FR, RR, FL, RL obtained by referring to the output signal of the target wheel FR with a threshold (condition (II)), the target wheel FR, Wheels associated with RR, FL, RL Based on the output signals of the wheel speed sensors 21, 22, 23, 24 that determine whether or not disturbance is mixed in the output signals of the sensors 21, 22, 23, and 24, and determine that the disturbance is not mixed A control device 1 that outputs the values of the rotational speeds of the wheels FR, RR, FL, and RL, or outputs a determination result as to whether disturbance is mixed in the output signals of the wheel speed sensors 21, 22, 23, and 24. Configured.

  According to this embodiment, the accuracy of the vehicle speed information based on the output signals of the wheel speed sensors 21, 22, 23, and 24 can be increased in a low speed range where the vehicle travels slowly. It becomes possible to detect a low vehicle speed of 10 km / h or less and provide the information to a parking assistance system or the like.

  The present invention is not limited to the embodiment described in detail above. For example, in the right wheel rotation speed output unit 15, the number of pulses output by the wheel speed sensor 21 or the wheel speed sensor 22 within a unit time (for example, 50 milliseconds) is integrated for a predetermined time, and the integrated value is added to the right front wheel. You may make it output as a value which suggests the rotational speed or vehicle speed of FR. In this case, the output pulse number of the wheel speed sensor 21 associated with the right front wheel FR is used for each of a plurality of unit times included in the latest predetermined time, or the output of the wheel speed sensor 22 associated with the right rear wheel RR is used. Select whether to use the number of pulses. That is, if it is determined that disturbance is not mixed in the output signal of the wheel speed sensor 21 for a certain unit time, the number of output pulses of the wheel speed sensor 21 is transferred to the integrated value as the number of pulses in the unit time, and the wheel speed is If it is determined that disturbance is mixed in the output signal of the sensor 21 but disturbance is not mixed in the output signal of the wheel speed sensor 22, the number of output pulses of the wheel speed sensor 22 is integrated as the number of pulses in the unit time. Move into the value. Alternatively, if it is determined that disturbance is mixed in the output signals of both the wheel speed sensors 21 and 22, the number of output pulses of the wheel speed sensor 21 is transferred to the integrated value as the number of pulses in the unit time.

  Similarly, in the left wheel rotational speed output unit 16, the number of pulses output by the wheel speed sensor 23 or the wheel speed sensor 24 within a unit time (for example, 50 milliseconds) is integrated for a predetermined time, and the integrated value is obtained as the left front wheel. You may make it output as a value which suggests the rotational speed or vehicle speed of FL. In this case, the number of output pulses of the wheel speed sensor 23 associated with the left front wheel FL is used for each of a plurality of unit times included in the latest predetermined time, or the output of the wheel speed sensor 24 associated with the left rear wheel RL. Select whether to use the number of pulses. That is, if it is determined that disturbance is not mixed in the output signal of the wheel speed sensor 23 for a certain unit time, the number of output pulses of the wheel speed sensor 23 is transferred to the integrated value as the number of pulses in the unit time, and the wheel speed is If it is determined that disturbance is mixed in the output signal of the sensor 23 but that disturbance is not mixed in the output signal of the wheel speed sensor 24, the number of output pulses of the wheel speed sensor 24 is integrated as the number of pulses in the unit time. Move into the value. Alternatively, if it is determined that disturbance is mixed in the output signals of both the wheel speed sensors 23, 24, the number of output pulses of the wheel speed sensor 23 is transferred to the integrated value as the number of pulses in the unit time.

  In addition, the specific configuration of each part, the content of processing, and the like can be variously modified without departing from the spirit of the present invention.

  The present invention can be used for vehicle control.

1 ... Control device (ECU)
21, 22, 23, 24 ... wheel speed sensors FR, RR, FL, RL ... wheels provided in the vehicle

Claims (1)

In a vehicle in which a wheel speed sensor for detecting the rotational speed of the wheel is attached to each of a plurality of wheels included in the vehicle,
Compare the output signal of the wheel speed sensor associated with the target wheel with the output signal of the wheel speed sensor associated with the other wheels, or refer to the output signal of the wheel speed sensor associated with the target wheel. By comparing the amount of change in the rotational speed of the target wheel per unit time obtained per unit time with a threshold value, it is determined whether disturbance is mixed in the output signal of the wheel speed sensor associated with the target wheel. ,
Outputs the value of the rotational speed of the wheel based on the output signal of the wheel speed sensor determined that the disturbance is not mixed, or determines whether the disturbance is mixed in the output signal of the wheel speed sensor. Control device to output.

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