JP2008265513A - Vehicle control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize the proper vehicle control by accurately determining whether the racing noise is caused or not. <P>SOLUTION: In ABS-ECU 30, a racing noise determination section 32 determines whether the racing noise that the car speed higher than the real speed is detected due to vibration of a vehicle is caused or not based on a determination whether the car speed more than a predetermined value is detected or not. A car speed computing section 34 computes the speed more than a predetermined threshold value as the car speed in the case wherein a determination that the racing noise is caused is done, and outputs the computed car speed to an EPS-ECU 40 for starting operation of an electric power steering mechanism 22 when a predetermined threshold value of car speed is input. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a vehicle control apparatus, and more particularly, to a vehicle control apparatus that controls equipment mounted on a vehicle according to a detected vehicle speed.

  A wheel speed sensor is provided around the wheel of the vehicle, and this wheel speed sensor outputs a signal indicating the rotation speed of the wheel to an electronic control unit provided in the vehicle body. The electronic control unit calculates the vehicle speed using a signal input from the wheel speed sensor, and further performs anti-skid control such as ABS (AntilockBrakeSystem) using the calculated vehicle speed.

On the other hand, when the engine speed increases, even when the vehicle is not moving, the engine vibration is transmitted to the rotor via the drive shaft and the vehicle is stopped. Nevertheless, it is known that so-called “racing noise” is generated in which the speed is detected by the wheel speed sensor. When such racing noise occurs, anti-skid control that is originally unnecessary may be executed. For this reason, for example, when the vehicle is in a stopped state and the engine speed is larger than the set speed, an anti-skid control device that sets a prohibition flag that prohibits execution of anti-skid control is proposed as the engine is in a racing state. (For example, refer to Patent Document 1). Further, for example, a traction control device that suppresses execution of traction control when the engine speed exceeds a predetermined speed has been proposed (see, for example, Patent Document 2).
JP-A-9-11882 JP 2005-96552 A

  Since racing noise is generated when the engine rotates at a high speed while the vehicle is stopped, the vehicle when the engine is rotated at a high speed while the vehicle is stopped is determined by determining whether the racing noise is generated. Control can be performed. For this reason, in the case of employing such vehicle control, it is extremely important to appropriately detect whether racing noise has occurred or not when implementing appropriate vehicle control.

  On the other hand, as a result of the inventor's earnest research and development, it has been found that the speed may be detected even when the vehicle is stopped, for example, due to the vibration of the vehicle when the door is closed. As a result, it has become clear that it is difficult to accurately determine whether or not racing noise has occurred, for example, only by determining whether or not the speed is detected by the wheel speed sensor while the vehicle is stopped.

  The present invention has been made in view of these problems, and an object of the present invention is to realize appropriate vehicle control by accurately determining whether or not racing noise has occurred.

  In order to solve the above-described problems, in a vehicle control device according to an aspect of the present invention, has racing noise generated to detect a vehicle speed due to vehicle vibration generated by engine operation even when the vehicle is stopped? A racing noise determining means for determining whether or not racing noise has occurred, a speed equal to or higher than a predetermined threshold is calculated as a vehicle speed, and the calculated vehicle speed is applied to the vehicle using the input vehicle speed. Vehicle speed calculation means for outputting to vehicle equipment control means for controlling the operation of the mounted equipment. The racing noise determination means determines whether racing noise has occurred based on whether a vehicle speed having a value within a predetermined range is detected.

  According to this aspect, the predetermined value is set to be larger than the speed that can be detected by the vibration of the vehicle, for example, by closing the door, even though the racing noise is not generated by the vibration of the vehicle. Therefore, it is possible to avoid erroneous determination that racing noise has occurred, and it is possible to appropriately control equipment mounted on the vehicle.

  Another aspect of the present invention is also a vehicle control device. This device includes racing noise determining means for determining whether or not a racing noise for detecting a vehicle speed due to the vibration of the vehicle generated by the operation of the engine even when the vehicle is stopped, and the generation of the racing noise. When it is determined that the vehicle speed has been determined, a speed equal to or greater than a predetermined threshold is calculated as the vehicle speed, and the calculated vehicle speed is output to the vehicle device control means that controls the operation of the device mounted on the vehicle using the input vehicle speed. Vehicle speed calculation means. The racing noise determination means determines whether racing noise has occurred based on whether the engine is operating.

  Racing noise is generated when the engine is running at high speed, that is, when the engine is operating. According to this aspect, it is possible to avoid erroneous determination that the vehicle speed is detected by the vibration of the vehicle when the engine is not operating and the racing noise is generated, and the devices mounted on the vehicle are appropriately controlled. be able to.

  The vehicle speed calculation means may output the calculated vehicle speed to a power steering mechanism control means for starting the operation of the power steering mechanism when a predetermined threshold vehicle speed is input.

  When the operation of the power steering mechanism is controlled as described above, the operation is performed even when it is erroneously determined that the racing noise has occurred, and there is a possibility that the driver operating the steering wheel may feel uncomfortable. According to this aspect, it is possible to avoid a situation in which the power steering mechanism is erroneously operated due to erroneous determination that racing noise has occurred, and it is possible to prevent the driver from feeling uncomfortable.

  According to the present invention, appropriate vehicle control can be realized by accurately determining whether or not racing noise has occurred.

  Hereinafter, embodiments of the present invention (hereinafter referred to as “embodiments”) will be described in detail with reference to the drawings.

(First embodiment)
FIG. 1 is an overall configuration diagram schematically showing a vehicle 10 according to the first embodiment. The vehicle 10 is configured by assembling a vehicle body 12 with a left front wheel 14FL, a right front wheel 14FR, a left rear wheel 14RL, and a right rear wheel 14RR (hereinafter collectively referred to as “wheels 14” as necessary). . The vehicle 10 is provided with a wheel speed sensor 16 that detects the rotational speed of each of the wheels 14. The wheel speed sensor 16 according to the first embodiment has a Hall IC, and the Hall IC detects unevenness of a pulsar protruding at equal intervals in the circumferential direction of the outer periphery of a drive shaft (not shown) that drives the wheel 14. Then, a digital signal is output as a detection signal indicating the rotational speed of each wheel 14. The vehicle 10 according to the first embodiment is equipped with an ABS (Antilock Brake System) that controls the braking force applied to each wheel 14 in accordance with the rotational speed of each wheel 14. The vehicle 10 is provided with an ABS electronic control unit (hereinafter referred to as “ECU”) 30 for realizing ABS. Each wheel speed sensor 16 is connected to the ABS-ECU 30, and a detection signal detected by the wheel speed sensor 16 is output to the ABS-ECU 30. A magnetoresistive element (MRE) sensor may be employed as the wheel speed sensor 16. Further, instead of the pulsar formed with unevenness, a magnet may be provided on the drive shaft so that the south pole and the north pole pass alternately in the vicinity of the wheel speed sensor 16 during rotation. Of course, the wheel speed sensor 16 is not limited to outputting such a digital signal.

  On the other hand, an electric power steering mechanism 22 is mounted on the vehicle 10. The electric power steering mechanism 22 gives rotational torque to the steering shaft 20. Since the electric power steering mechanism 22 is a known technique, a description of its configuration is omitted. A steering wheel 18 operated by a driver is attached to one end of the steering shaft 20, and the other end of the steering shaft 20 is connected to a turning mechanism (not shown). In the vehicle 10 according to the first embodiment, the left front wheel 14FL and the right front wheel 14FR are configured to be steerable. The steering mechanism converts the rotational motion of the steering shaft 20 into the steering motion of the left front wheel 14FL and the right front wheel 14FR.

  The vehicle 10 is provided with an EPS-ECU (EPS: Electric Power Steering) 40 that controls the operation of the electric power steering mechanism 22. The EPS-ECU 40 applies rotational torque to the steering shaft 20 by controlling the operation of the electric power steering mechanism 22 according to the traveling speed of the vehicle 10 (hereinafter referred to as “vehicle speed”), the steering direction, and the like, Assist the driver's operating force. For this reason, the EPS-ECU 40 is connected to the ABS-ECU 30 and receives data indicating the vehicle speed from the ABS-ECU 30.

  FIG. 2 is a functional block diagram of the vehicle 10 according to the first embodiment. In FIG. 2, the ABS-ECU 30 includes a CPU that executes various arithmetic processes, a ROM that stores various control programs, hardware such as a RAM that is used as a work area for data storage and program execution, and software. The functional blocks to be realized are drawn. Therefore, these functional blocks can be realized in various forms by a combination of hardware and software.

  The ABS-ECU 30 includes a racing noise determination unit 32, a vehicle speed calculation unit 34, and a braking control unit 36. The vehicle speed calculation unit 34 calculates the rotation speed of each wheel 14 using the detection signal input from the wheel speed sensor 16 and converts the rotation speed of each wheel 14 to the vehicle speed when the wheel rotates at the rotation speed. The wheel speed that is the calculated value is calculated. Note that the vehicle 10 according to the first embodiment is a front wheel drive vehicle, and the vehicle speed calculation unit 34 normally calculates the average value of the wheel speeds of the left front wheel 14FL and the right front wheel 14FR, which are drive wheels, as the vehicle speed. The vehicle speed calculation unit 34 calculates the calculated vehicle speed in addition to the EPS-ECU 40, an engine ECU (not shown) that controls the operation of the engine, a vehicle speed meter provided on an instrument panel in the cabin of the vehicle 10, and the vehicle 10 is output to other vehicle control systems for controlling 10.

  The braking control unit 36 is connected to a pressure increasing solenoid valve and a pressure reducing solenoid valve in the hydraulic actuator via a drive circuit. The braking control unit 36 utilizes the calculated wheel speeds of the wheels 14 and the like, so that a target braking mechanism provided for each of the wheels 14 is provided so as to apply an appropriate braking force to each of the wheels 14. Determine wheel cylinder pressure. The brake control unit 36 increases or decreases the wheel cylinder pressure of each brake mechanism to the target wheel cylinder pressure by supplying a control current to the drive circuit and controlling the duty of the current supplied to these solenoid valves. Anti-skid control for controlling the braking force applied to each of the wheels 14 is performed. Note that the structure of the hydraulic actuator and the brake mechanism and the control method of the anti-skid control are well-known techniques, and thus description thereof is omitted.

  The engine ECU controls the operation of the engine based on the vehicle speed input from the ABS-ECU 30. However, the engine ECU according to the first embodiment, for example, when the vehicle 10 is in a muddy state, the vehicle load is applied, and the vehicle speed is high even though the engine is rotating at a high speed. May fail if almost no is detected. On the other hand, when the vehicle is in such a state, racing engine is generated because the engine rotates at a high speed even though the vehicle does not travel. For this reason, the inventor determines whether or not racing noise has occurred, and when racing noise occurs, the vehicle speed is higher than the vehicle speed calculated from the average wheel speed of the drive wheels. The present inventors have found a technique for outputting a predetermined speed at which the vehicle 10 is traveling at a very low speed to the engine ECU as a vehicle speed. Thereby, even when the vehicle 10 is stuck in the mud as described above, a vehicle speed at which the vehicle is moving at a very low speed is input to the engine ECU, so that the occurrence of a failure of the engine ECU is suppressed. It becomes possible to do.

  Therefore, the racing noise determination unit 32 calculates the wheel speed of each of the wheels 14 using the detection signal of the wheel speed sensor 16, and determines whether racing noise is generated using the calculated wheel speed. judge. When it is determined that racing noise is occurring, the vehicle speed calculation unit 34 suppresses the occurrence of a failure of the engine ECU by calculating a predetermined speed as the vehicle speed. In the first embodiment, in this case, the vehicle speed calculation unit 34 sets the wheel speed of the wheel 14 having the smallest wheel speed among the four wheels 14 to 1.75 km or less if the wheel speed is greater than 1.75 km. Then, 1.75 km is calculated as the vehicle speed.

  On the other hand, in recent years, with the wheel speed sensor being digitized, it is possible to detect the rotation even when the wheel rotates at a very slow rotation speed. Even when the inventor performs an action of applying vibration to the vehicle 10 by, for example, closing the door of the vehicle 10 due to such high accuracy of the wheel speed sensor, the wheel speed sensor 16 is driven by the vibration of the vehicle 10. It has been discovered that 14 rotations may be detected. For this reason, for example, even when the ignition switch is turned on but the engine has not yet been started, even when racing noise cannot be generated, the driver closes the door of the vehicle 10 to cause the wheel speed sensor 16 to move to the wheel 14. May be erroneously determined that racing noise has occurred. When such an erroneous determination occurs, a speed higher than the vehicle speed calculated from the average value of the wheel speeds of the drive wheels is output to the EPS-ECU 40, etc., even though no racing noise has occurred.

  Here, in the EPS-ECU 40 according to the first embodiment, when the engine speed exceeds a predetermined speed (for example, 450 rpm) or the vehicle speed input from the ABS-ECU 30 is a predetermined speed (for example, , 0.1 km / h), the operation of the electric power steering mechanism 22 is started. For this reason, if it is erroneously determined that racing noise has occurred as described above and a vehicle speed of a predetermined value or higher is output to the EPS-ECU 40 even though the vehicle 10 is stopped, the EPS- The ECU 40 can start the operation of the electric power steering mechanism 22 even though the engine of the vehicle 10 is not operating and the vehicle 10 is not traveling. For this reason, for example, when the driver closes the ignition switch while the vehicle is stopped, the driver may feel uncomfortable in the operation of the steering wheel 18 immediately after the door is closed.

  For this reason, the racing noise determination unit 32 according to the first embodiment is based on whether racing noise has occurred or when the door is closed based on whether or not a vehicle speed within a predetermined range is detected. It is determined whether noise is generated due to body vibration. The vehicle speed calculation procedure according to the first embodiment will be described below with reference to FIG.

  FIG. 3 is a flowchart showing the calculation procedure of the vehicle speed according to the first embodiment. The processing in this flowchart starts when the ignition switch is turned on and is repeatedly performed every predetermined time until the ignition switch is turned off.

  The inventor found that in most cases, the wheel speed detected when the vehicle 10 is vibrated, such as closing the door, is smaller than the wheel speed detected when the engine is rotating at high speed. I found For this reason, the racing noise determination unit 32 has a maximum driving wheel speed Vfmax, which is a higher wheel speed among wheel speeds of the left front wheel 14FL and the left front wheel 14FL as driving wheels, larger than a predetermined first speed threshold value Vth1. By determining whether or not, it is determined whether or not the detected wheel speed is due to the action of applying vibration to the vehicle 10 (S10). The first speed threshold value Vth1 is set to a value larger than the wheel speed detected when an action of applying vibration to the vehicle 10 such as closing a door is performed, and is stored in advance in a ROM or the like. In the first embodiment, the first speed threshold value Vth1 is set to 1.75 km / h.

  The racing noise determination unit 32 determines that the average value of the left front wheel 14FL and the right front wheel 14FR is greater than the first speed threshold value Vth1, instead of determining whether the maximum drive wheel speed Vfmax is greater than a predetermined first speed threshold value Vth1. You may determine whether it is large. When the maximum driving wheel speed Vfmax is larger than the first speed threshold Vth1 (Y in S10), it is determined that the detected wheel speed is not due to an action that gives vibration to the vehicle 10, and the racing noise determination unit 32 determines in S12. Transition.

  For example, when the engine rotates at a high speed with a traveling load applied, such as when the vehicle has become muddy, the minimum driving wheel speed Vfmin becomes smaller than the maximum driving wheel speed Vfmax. Therefore, the racing noise determination unit 32 determines whether or not the minimum driving wheel speed Vfmin / the maximum driving wheel speed Vfmax is equal to or less than a predetermined speed ratio K (S12). Note that K is set in advance as a speed ratio of the wheel speeds of the left front wheel 14FL and the right front wheel 14FR that normally appear when the vehicle is muddled, and is stored in a ROM or the like in advance. In the first embodiment, K is set to 0.6.

  When it is determined that the minimum driving wheel speed Vfmin / the maximum driving wheel speed Vfmax is equal to or lower than K (Y in S12), the racing noise determination unit 32 calculates the vehicle speed Vc calculated by averaging the wheel speeds of the left front wheel 14FL and the right front wheel 14FR. It is determined whether or not the vehicle 10 is stopped by determining whether or not the vehicle speed is equal to or less than the second speed threshold value Vth2 (S14). The second speed threshold value Vth2 is set to a value that can determine that the vehicle 10 is stopped if the vehicle speed is lower than that, and is stored in advance in a ROM or the like. In the first embodiment, the second speed threshold value Vth2 is set to 2 km / h.

  When it is determined that the vehicle speed Vc is equal to or lower than the second speed threshold value Vth2 (Y in S14), the racing noise determination unit 32 determines that the vehicle 10 is stopped and the left front wheel 14FL that is normally generated when the vehicle 10 gets muddy and the right Since the speed ratio with the front wheel 14FR is also detected, it is determined that racing noise has occurred. When it is determined that the racing noise has occurred, the vehicle speed calculation unit 34 sets a value equal to or higher than the predetermined vehicle speed Vc1 as the vehicle speed Vc in order to suppress the occurrence of a failure in the engine ECU. Output. Note that the predetermined vehicle speed Vc1 is set to a value that does not cause the engine ECU to fail even if it is input to the engine ECU when it gets stuck, and is stored in the ROM in advance. In the first embodiment, the predetermined vehicle speed Vc1 is set to 1.75 km / h.

  Specifically, the vehicle speed calculation unit 34 determines whether or not the predetermined vehicle speed Vc1 is greater than the lowest wheel speed Vmin that is the lowest value among the wheel speeds of the four wheels 14 (S16). If the predetermined vehicle speed Vc1 is greater than the minimum wheel speed Vmin (Y in S16), the predetermined vehicle speed Vc1 is calculated as the vehicle speed Vc (S18). If the predetermined vehicle speed Vc1 is equal to or lower than the minimum wheel speed Vmin (N in S16), the minimum wheel speed Vmin is calculated as the vehicle speed Vc (S20).

  When it is determined that the maximum drive wheel speed Vfmax is equal to or less than the first speed threshold Vth1 (N in S10), or when it is determined that the minimum drive wheel speed Vfmin / the maximum drive wheel speed Vfmax is greater than K (N in S12), noise Therefore, the average value of the wheel speeds of the left front wheel 14FL and the right front wheel 14FR is directly calculated as the vehicle speed Vc (S22). When it is determined that the vehicle speed Vc is greater than the second speed threshold value Vth2 (N in S14), the racing noise determination unit 32 determines that noise has occurred due to vehicle body vibration caused by closing a door, not racing noise. Then, the average value of the wheel speeds of the left front wheel 14FL and the right front wheel 14FR is directly calculated as the vehicle speed Vc (S22).

  When the vehicle speed Vc is calculated, the ABS-ECU 30 outputs the calculated vehicle speed Vc to each vehicle control device mounted on the vehicle 10 including the EPS-ECU 40 and the engine ECU. At this time, in the vehicle speed calculation process according to the first embodiment, since it is determined that racing noise has occurred due to closing of the door and the like, it is suppressed that a speed greater than the actual value is output. The malfunction of the steering mechanism 22 can be reduced, and the driver's uncomfortable feeling with respect to the operation of the steering wheel 18 can be suppressed.

(Second Embodiment)
The vehicle 10 according to the second embodiment is provided with a crank angle sensor. The crank angle sensor detects a crank angle that is a rotational phase of a crankshaft connected to the piston of the engine. The engine speed can be calculated using the crank angle detected by the crank angle sensor. For this reason, the crank angle sensor also functions as an engine speed sensor for detecting the engine speed. The crank angle sensor is connected to the engine ECU, and a detection signal of the crank angle sensor is output to the engine ECU. The engine ECU calculates the engine speed using the detection signal input from the crank angle sensor. The engine ECU outputs information indicating the calculated engine speed to the ABS-ECU 30. Unless otherwise specified, other configurations and control procedures of the vehicle 10 according to the second embodiment are the same as those of the vehicle 10 according to the first embodiment.

  FIG. 4 is a flowchart showing a calculation procedure of the vehicle speed according to the second embodiment. The processing in this flowchart starts when the ignition switch is turned on and is repeatedly performed every predetermined time until the ignition switch is turned off.

  Of course, when the engine is running at a high speed with a running load applied, such as when the vehicle gets stuck, the engine is operating. For this reason, the racing noise determination unit 32 uses the information indicating the engine speed input from the engine ECU to determine whether the engine speed is greater than the predetermined speed Nth, thereby operating the engine. It is determined whether or not (S30). The predetermined rotation speed Nth is set to a rotation speed at which it can be determined that the engine is operating, and is stored in the ROM in advance. In the second embodiment, the predetermined rotation speed Nth is set to 450 rpm.

  If the engine speed is greater than the predetermined speed Nth (Y in S30), it can be determined that the engine is operating, so the racing noise determination unit 32 next determines whether the maximum drive wheel speed Vfmax is zero. That is, it is determined whether or not the wheel speed is detected on the left front wheel 14FL or the right front wheel 14FR which is the driving wheel (S32). When it is determined that the maximum driving wheel speed Vfmax is not zero, the racing noise determination unit 32 proceeds to determination of S34. When the engine speed is equal to or lower than the predetermined speed Nth (N in S30) and when the maximum driving wheel speed Vfmax is zero (N in S32), the racing noise determination unit 32 is in a state where racing noise can be generated. Therefore, it is determined that no racing noise has occurred. When it is determined that no racing noise has occurred, the vehicle speed calculation unit 34 calculates the average value of the wheel speeds of the left front wheel 14FL and the right front wheel 14FR as it is as the vehicle speed Vc (S44). S34 to S44 are the same as S12 to S22 in FIG.

  Thus, the racing noise determination unit 32 according to the second embodiment determines whether or not racing noise has occurred based on whether or not the engine is operating. By determining the occurrence of racing noise in this way, it is possible to suppress erroneous determination that racing noise has occurred, for example, by closing a door even when the engine is not operating.

  The present invention is not limited to the above-described embodiments, and various modifications such as design changes can be added to the embodiments based on the knowledge of those skilled in the art. Embodiments described may also fall within the scope of the present invention. Here are some examples.

  The vehicle 10 may be a rear wheel drive vehicle. In this case, the racing noise determination unit 32 and the vehicle speed calculation unit 34 normally output the average value of the wheel speeds of the left rear wheel 14RL and the right rear wheel 14RR as the vehicle speed Vc. Further, in this case, the maximum driving wheel speed Vfmax is the larger wheel speed of the left rear wheel 14RL and the right rear wheel 14RR, and the minimum driving wheel speed Vfmin is the wheel speed of the left rear wheel 14RL and the right rear wheel 14RR. The wheel speed is the smaller of the two.

1 is an overall configuration diagram schematically showing a vehicle according to a first embodiment. It is a functional block diagram of the vehicle concerning a 1st embodiment. It is a flowchart which shows the calculation procedure of the vehicle speed which concerns on 1st Embodiment. It is a flowchart which shows the calculation procedure of the vehicle speed which concerns on 2nd Embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 vehicle, 12 vehicle main body, 14 wheel, 16 wheel speed sensor, 22 electric power steering mechanism, 30 ABS-ECU, 32 racing noise determination part, 34 vehicle speed calculating part, 36 brake control part, 40 EPS-ECU.

Claims (3)

Racing noise determining means for determining whether or not a racing noise in which the vehicle speed is detected by the vibration of the vehicle generated by the operation of the engine despite the vehicle being stopped, and
When it is determined that racing noise has occurred, a vehicle device that calculates a speed equal to or higher than a predetermined threshold as a vehicle speed and uses the input vehicle speed to control the operation of a device mounted on the vehicle. Vehicle speed calculation means for outputting to the control means;
With
The racing noise determining means determines whether or not racing noise has occurred based on whether or not a vehicle speed having a value within a predetermined range is detected. Racing noise determining means for determining whether or not a racing noise in which the vehicle speed is detected by the vibration of the vehicle generated by the operation of the engine despite the vehicle being stopped, and
When it is determined that racing noise has occurred, a vehicle device that calculates a speed equal to or higher than a predetermined threshold as a vehicle speed and uses the input vehicle speed to control the operation of a device mounted on the vehicle. Vehicle speed calculation means for outputting to the control means;
With
The racing noise determining means determines whether or not racing noise has occurred based on whether or not the engine is operating.   The vehicle speed calculation means outputs the calculated vehicle speed to a power steering mechanism control means for starting the operation of the power steering mechanism when the predetermined vehicle speed is inputted. The vehicle control device described.

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