JP2007145186A - Controller for vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a controller for avoiding the deterioration of the stability of the behavior of a vehicle even when any abnormality is generated in a vehicle in the case of controlling the roll status of a vehicle by applying a torque to a wheel. <P>SOLUTION: The controller of a vehicle is provided with: a suspension mechanism supported by a vehicle independently of front and rear wheels; a driving/braking torque control means for independently controlling the driving torque and braking torque of the front and rear wheels, a roll detection means for detecting the roll status of the vehicle; and a roll control means for controlling the roll status by giving a driving torque or a braking torque to the front and rear wheels by the driving/braking torque control means according to the roll status, and for controlling the roll status. This controller is provided with vehicle abnormality detection means (steps S101 to S103) for detecting the abnormality of the vehicle and a roll control changing means (steps S101 to S103) for changing the control content of the roll status by the roll control means when the abnormality of the vehicle is detected by the vehicle abnormality detecting means. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a vehicle control device that controls the behavior of a vehicle by independently controlling the torque applied to the wheels of the vehicle.

  In recent years, so-called in-wheel motor vehicles have been developed as one form of electric vehicles, in which a motor is incorporated in a wheel and the wheel is directly driven by the motor. As an advantage of this in-wheel motor type electric vehicle, each motor (drive wheel) is individually controlled for rotation, that is, each motor is individually controlled for power running or regenerative control, and given to each drive wheel. The driving force or braking force of the vehicle can be individually controlled, and the driving force and braking force of the vehicle can be appropriately controlled according to the running state, and the conventional drive train such as the engine or transmission is eliminated. As a result, it is possible to widen the space such as the interior of the vehicle or the trunk room.

  Of these, by making use of the fact that the driving torque or braking torque applied to each wheel can be controlled individually, by providing a difference in the magnitude of the driving torque (or braking torque) between the left and right front wheels A control device has been studied in which a vertical force is generated on a vehicle body to suppress a roll of the vehicle body that occurs during turning.

  In the control device for an in-wheel motor vehicle as described above, when a roll is generated in the vehicle body, the deviation obtained by subtracting the drive torque acting on the front wheels from the drive torque acting on the rear wheels on which the vehicle body sinks is large. Thus, by controlling the driving torque or braking torque applied to the front and rear wheels, a force for lifting the vehicle body is generated on the side where the vehicle body sinks during rolling, and the vehicle body is lifted when rolling. By controlling the driving torque or braking torque applied to the front and rear wheels so that the deviation obtained by subtracting the driving torque acting on the front wheels from the driving torque acting on the rear wheels is reduced, The force of pushing down is generated, and the roll of the vehicle body is suppressed.

  Therefore, a force to lift the vehicle body, that is, a force to suppress the vehicle body sinking when rolling, is generated on the side where the vehicle body sinks when the vehicle body rolls, and on the side where the vehicle body floats when rolling the vehicle body Controlling the roll of the vehicle body by controlling the driving torque or braking torque applied to each wheel so as to generate a force to push down the vehicle body, that is, a force to suppress the lifting of the vehicle body when rolling Can do.

  However, when executing the roll control for suppressing the roll of the vehicle body as described above, for example, the tire air pressure of the wheel is decreased, the various sensors / devices used for the roll control have failed, or when turning If an abnormality such as the turning inner ring floating from the ground contact surface occurs, the desired roll control may not be performed properly. For example, if the normal roll control is continued when the tire pressure of one of the wheels is lower than that of the other wheels, the tire stiffness of the wheel whose tire pressure has decreased is reduced, so only that wheel There is a possibility that control responsiveness is reduced, and an unintended yaw moment is generated during roll control, or a moment that promotes the roll is generated. Thus, there is still room for improvement in the prior art.

  The present invention has been made paying attention to the above technical problem, and is a case where an abnormality occurs in the vehicle when controlling the roll state of the vehicle body by individually controlling the torque applied to each wheel. Another object of the present invention is to provide a vehicle control device capable of avoiding that the roll control is continued and the stability of the behavior of the vehicle is reduced.

  In order to achieve the above object, the invention of claim 1 is directed to a suspension mechanism for independently supporting at least front and rear wheels on a vehicle body, and braking / driving torque for independently controlling driving torque and braking torque of the front and rear wheels. A driving means or a braking torque is applied to the front and rear wheels by the braking / driving torque control means in accordance with the roll state detected by the control means, a roll detecting means for detecting the roll state of the vehicle body, and the roll detecting means. In a vehicle control device comprising a roll control means for controlling the roll state, when a vehicle abnormality is detected by the vehicle abnormality detection means for detecting abnormality of the vehicle and the vehicle abnormality detection means, And a roll control changing means for changing the control content of the roll state by the roll control means. It is the location.

  The invention according to claim 2 is the invention according to claim 1, wherein the vehicle abnormality detection means detects the filling gas pressure of the tires of the front and rear wheels and determines whether or not the pressure is lower than a predetermined filling gas pressure. Including a means for determining, and when the roll control changing means detects that the filling gas pressure of one of the front and rear tires is lower than a predetermined filling gas pressure by the vehicle abnormality detection means. The control device includes means for reducing drive torque or braking torque applied to the front and rear wheels for controlling the roll state.

  In this case, when the vehicle abnormality detection means detects that the filling gas pressure of one of the front and rear wheels is lower than a predetermined filling gas pressure, the control of the roll state is performed. Therefore, the means for reducing the driving torque or braking torque applied to the front and rear wheels is “when the vehicle abnormality detection means detects a decrease in the filling gas pressure of any tire of the front and rear wheels,” Means for reducing the driving torque or braking torque applied to the front and rear wheels to “0” for the control of the roll state ”, that is,“ the vehicle abnormality detection means When a decrease is detected, a means for not outputting drive torque or braking torque applied to the front and rear wheels for controlling the roll state, in other words, “front If the decrease of the filling gas pressure of any tire of the front and rear wheels is detected by the vehicle abnormality detection means includes means "to prohibit the execution of control of the roll state.

  Further, the invention according to claim 3 is the invention according to claim 1 or 2, wherein the vehicle abnormality detection means detects the filling gas pressure of the tires of the front and rear wheels and is lower than a predetermined filling gas pressure. And a means for identifying a wheel in which a decrease in the filling gas pressure has occurred, and the roll control change means is configured to reduce the filling gas pressure of any of the front and rear wheels by the vehicle abnormality detection means. When detected, a decrease in the filling gas pressure of the tire is not detected with respect to the control of the roll state in which a driving torque or a braking torque is applied to the wheel in which a decrease in the filling gas pressure of the tire is detected. It is a control device including means for executing control of the roll state for applying driving torque or braking torque to a wheel with a predetermined delay time.

  According to a fourth aspect of the present invention, in the first aspect of the invention, the vehicle abnormality detecting means includes means for detecting an abnormality of a device used for controlling the roll state, and the roll control changing means includes: A control device comprising: means for prohibiting execution of the roll state control when an abnormality of the device is detected by the vehicle abnormality detection means.

  Further, the invention of claim 5 is the invention according to any one of claims 1 to 4, wherein the suspension mechanism is configured such that the center of instantaneous rotation in a side view of the vehicle is located between the front wheel and the rear wheel. The roll control means includes means for controlling the roll state by providing a difference in driving torque or braking torque between the front and rear wheels applied by the braking / driving torque control means. It is a control device.

  According to a sixth aspect of the present invention, the braking / driving torque control means includes means for controlling the driving torque and braking torque by controlling rotation of an electric motor that independently applies torque to the front and rear wheels. Is a control device characterized by

  According to the first aspect of the present invention, the driving torque or braking torque applied to the front and rear wheels is independently controlled, and the vertical force is applied to the vehicle body via the suspension mechanism, whereby the vehicle body roll state The roll control for controlling is executed. At this time, when the state of the vehicle is detected and it is detected that the vehicle state is abnormal, the control content of the roll control is appropriately changed. Therefore, even when an abnormality occurs in the vehicle during execution of the roll control, it can be avoided that the roll control is continued and the stability of the behavior of the vehicle is lowered.

  According to the invention of claim 2, when the roll control is executed, the filling gas pressure of the front and rear tires is higher than a predetermined filling gas pressure that is predetermined as the filling gas pressure of the tire in a normal state. If it is detected that the driving force is also reduced, the driving torque and braking torque applied to each wheel in order to execute the roll control are reduced. Alternatively, the driving torque and braking torque applied to each wheel to perform roll control are made zero, that is, the driving torque and braking torque applied to each wheel to perform roll control are not output, in other words Execution of roll control is prohibited. Therefore, it is possible to avoid or suppress a situation where inappropriate roll control is continued and the stability of the behavior of the vehicle is reduced.

  Further, according to the invention of claim 3, when the roll control is executed, when it is detected that the filling gas pressure of the tire of any one of the front and rear wheels is lower than the predetermined filling gas pressure, Roll control that applies driving torque or braking torque to a wheel with normal tire filling gas pressure, compared to roll control that applies driving torque or braking torque to a wheel in which a decrease in the charging gas pressure of the tire is detected, It is executed with a predetermined delay time. For this reason, it is possible to avoid or suppress the occurrence of imbalance in control responsiveness and the inadequate roll control being continued to reduce the stability of the behavior of the vehicle.

  According to the fourth aspect of the present invention, when roll control is executed, if an abnormality is detected in various devices such as sensors and actuators used for roll control, the roll control is prohibited from being executed. Is done. Therefore, even when an abnormality occurs in the vehicle during execution of the roll control, it can be avoided that the roll control is continued and the stability of the behavior of the vehicle is lowered.

  Furthermore, according to the invention of claim 5, the suspension mechanism for supporting the front and rear wheels on the vehicle body is such that the center of instantaneous rotation in the vehicle side view is always located between the front wheel and the rear wheel in the front-rear direction of the vehicle. A difference in driving torque or braking torque applied to the front wheel and the rear wheel, that is, a difference in magnitude or direction of torque applied to the front wheel and the rear wheel, in other words, the front wheel By making the torque (driving torque or braking torque) applied to the rear wheel different from each other, a vertical force is applied to the vehicle body. Therefore, the driving torque or braking torque to be applied to the front wheels and the driving torque or braking torque to be applied to the rear wheels are provided with at least a difference between them, in other words, they are different from each other and controlled to an arbitrary magnitude. By doing so, the vertical force applied to the vehicle body can be arbitrarily set, and roll control can be easily executed.

  According to the sixth aspect of the present invention, the torque applied to the front and rear wheels is controlled by independently controlling the rotation of the electric motor incorporated in each wheel. Therefore, roll control can be easily executed.

  Next, an embodiment of the present invention will be described with reference to the drawings. First, FIG. 4 shows the configuration and control system of a vehicle to which the present invention is applied. As a typical mode for carrying out the present invention, at least the front wheels 1 and 2 and the rear wheels 3 and 4 are independently supported on the vehicle body Bo, and are applied to the wheels 1, 2, 3 and 4, respectively. Braking / driving torque control means mainly comprising a motor 6 and an inverter 7 and a battery 8 for independently outputting driving torque and braking torque to be controlled, and an electronic control device 9 for controlling them, and a stroke sensor 10 for the suspension 5 And a roll detection means for detecting the roll state of the vehicle body Bo based on detection values of the lateral acceleration sensor 11 and the like, and each wheel 1, by the braking / driving torque control means according to the roll state of the vehicle body Bo detected by the roll detection means. Roll control means for applying driving torque or braking torque to 2, 3 and 4 and controlling the roll state of the vehicle body BoAnd, for example, a decrease in the filling gas pressure of the tire of each wheel 1, 2, 3, 4 estimated by a detection value of the wheel speed sensor 12 or detected by a gas pressure sensor (not shown) or the like, or For example, when the abnormality of the vehicle Ve is detected by the vehicle abnormality detecting means for detecting abnormality of the vehicle Ve such as the wheel speed sensor 12 or the failure of other sensors / devices, and the abnormality of the vehicle Ve is detected by the vehicle abnormality detecting means, the roll control described above is performed. Roll control changing means for changing the control content of the roll state of the vehicle body Bo by the means.

  Specifically, the vehicle Ve shown in FIG. 4 has left and right front wheels 1 and 2 and left and right rear wheels 3 and 4, and each wheel 1, 2, 3 and 4 is connected via a suspension 5. It is supported by the vehicle body Bo of the vehicle Ve. A motor 6 is incorporated in each wheel 1, 2, 3, 4 inside the wheel. That is, the motors 6 of the wheels 1, 2, 3 and 4 are so-called in-wheel motors, and the rotation of the motors 6 is independently controlled, so that the wheels 1, 2, 3 and 4 are controlled. The applied driving force and braking force can be controlled independently. Each of these motors 6 is an AC synchronous motor, for example, and is connected to a battery 8 via an inverter 7. The inverter 7 is connected to an electronic control unit (ECU) 9 that controls the rotation of each motor 6.

  When each motor 6 is driven, the DC power of the battery 8 is converted into AC power by the inverter 7, and the AC power is supplied to each motor 6 so that each motor 6 is powered and a driving torque is applied to the wheels. The Each motor 6 can be regeneratively controlled using the rotational energy of the wheels. That is, at the time of regeneration and power generation of each motor 6, the rotational (kinetic) energy of the wheels is converted into electric energy by each motor 6, and the electric power generated at that time is charged to the battery 8 via the inverter 7. At this time, braking torque based on regeneration and power generation is applied to the wheels.

  Thus, the driving torque and braking torque of each wheel 1, 2, 3, 4 are independently controlled by the motor 6, inverter 7, battery 8, ECU 9, etc. of each wheel 1, 2, 3, 4 respectively. Can do. Accordingly, each motor 6, inverter 7, battery 8, ECU 9 and the like function as braking / driving torque control means in the present invention.

  The suspension 5 that supports each wheel 1, 2, 3, 4 in which the motor 6 is incorporated is supported on the vehicle body Bo, for example, a strut suspension including a strut incorporating a shock absorber, a coil spring, a suspension arm, and the like, It is a known suspension mechanism such as a wishbone type suspension composed of a coil spring, a shock absorber, upper and lower suspension arms, etc., and these various suspension mechanisms can be appropriately selected and employed.

  Further, in each of the suspensions 5 of the wheels 1, 2, 3 and 4, the instantaneous rotation center in the side view of the vehicle Ve is between the front wheels 1 and 2 and the rear wheels 3 and 4 in the longitudinal direction of the vehicle Ve. It is comprised so that it may be located in. Specifically, as shown in FIG. 5, the respective instantaneous rotation centers C1, C2, C3, and C4 in the side view of the vehicle Ve of the suspensions 5 that support the wheels 1, 2, 3, and 4 on the vehicle body Bo, The vehicle Ve is always arranged between the front wheels 1 and 2 and the rear wheels 3 and 4 in the front-rear direction.

  In the vehicle Ve configured as described above, as shown in FIG. 5A, a force F2t in the direction of decelerating or braking the vehicle Ve is applied to the grounding point 2a of the front wheel 2 with respect to the traveling direction of the vehicle Ve. When torque that can be applied (in this case, braking torque) is applied to the front wheel 2, a component force F2sv vertically upward (upward in FIG. 5) is applied to the instantaneous rotation center C2 of the suspension 5 of the front wheel 2. A force F2s having In other words, a force F2sv in the direction of lifting the vehicle body Bo via the suspension 5 of the wheel 2, that is, the direction of suppressing the sinking of the vehicle body Bo during rolling (upward in FIG. 5) acts on the vehicle body Bo. Similarly, a torque (in this case, a driving torque) that can apply a force F4t in the direction of accelerating the vehicle Ve to the ground contact point 4a of the rear wheel 4 with respect to the traveling direction of the vehicle Ve is applied to the rear wheel 4. Then, a force F4s having a component force F4sv upward in the vertical direction acts on the instantaneous rotation center C4 of the suspension 5 of the rear wheel 4. In other words, a force F4sv acts in the vehicle body Bo in the direction of lifting the vehicle body Bo via the suspension 5 of the wheel 4, that is, in the direction of suppressing the sinking of the vehicle body Bo during rolling.

  On the other hand, as shown in FIG. 5B, torque (in this case, driving) that can apply force F1t in the direction of accelerating the vehicle Ve to the ground contact point 1a of the front wheel 1 with respect to the traveling direction of the vehicle Ve. When the torque is applied to the front wheel 1, a force F1s having a component force F1sv in the vertical downward direction (downward in FIG. 5) acts on the instantaneous rotation center C1 of the suspension 5 of the front wheel 1. In other words, a force F1sv acts in the vehicle body Bo in the direction of pushing down the vehicle body Bo via the suspension 5 of the wheel 1, that is, the direction in which the vehicle body Bo is prevented from lifting during rolling (downward in FIG. 5). Similarly, torque (in this case, braking torque) that can apply a force F3t in the direction of decelerating or braking the vehicle Ve to the ground contact point 3a of the rear wheel 3 with respect to the traveling direction of the vehicle Ve is applied to the rear wheel 3. When applied, a force F3s having a downward component force F3sv in the vertical direction acts on the instantaneous rotation center C3 of the suspension 5 of the rear wheel 3. In other words, a force F3sv acts in a direction in which the vehicle body Bo is pushed down via the suspension 5 of the wheel 3, that is, in a direction in which the vehicle body Bo is prevented from being lifted during rolling.

  Therefore, when a roll is generated in the vehicle body Bo of the vehicle Ve configured as described above, the driving torque or braking torque in the state shown in FIG. 5A is applied to the front and rear wheels on the side where the vehicle body Bo sinks. In other words, when the side shown in FIG. 5A is the side on which the vehicle body Bo sinks during rolling, the front wheel 2 is applied so that the force F2s acts on the instantaneous rotation center C2 of the suspension 5 of the front wheel 2. Controlling the in-wheel motor of the rear wheel 4, or controlling the in-wheel motor of the rear wheel 4 so that the force F4s acts on the instantaneous center of rotation C4 of the suspension 5 of the rear wheel 4, or instantaneous rotation of the suspension 5 of the front wheel 2. The in-wheel motors of the front and rear wheels 2 and 4 are controlled so that the force F2s acts on the center C2 and the force F4s acts on the instantaneous rotation center C4 of the suspension 5 of the rear wheel 4. In other words, the body Bo is controlled by controlling the in-wheel motors of the front and rear wheels 2 and 4 so that the deviation obtained by subtracting the torque applied to the front wheel 2 from the torque applied to the rear wheel 4 is increased. It is possible to generate a force Fu (force F2sv or force F4sv, or resultant force of force F2sv and force F4sv) in a direction in which the body Bo is lifted, that is, in a direction in which the body Bo is prevented from sinking during rolling.

  On the other hand, the driving torque or braking torque in the state shown in FIG. 5B is applied to the front and rear wheels on the side where the vehicle body Bo is lifted, that is, the side shown in FIG. Is the sinking side, the in-wheel motor of the front wheel 1 is controlled so that the force F1s acts on the instantaneous rotation center C1 of the suspension 5 of the front wheel 1, or the instantaneous rotation center C3 of the suspension 5 of the rear wheel 3 The in-wheel motor of the rear wheel 3 is controlled so that the force F3s acts on the wheel, or the force F1s acts on the instantaneous rotation center C1 of the suspension 5 of the front wheel 1 to the instantaneous rotation center C3 of the suspension 5 of the rear wheel 3. Controlling the in-wheel motors of the front and rear wheels 1 and 3 so that the force F3s acts, in other words, applying the torque applied to the rear wheel 3 to the front wheel 1 By controlling the in-wheel motors of the front and rear wheels 1 and 3 so as to reduce the deviation obtained by subtracting the generated torque, the force Fd in the direction of pushing down the vehicle body Bo against the vehicle body Bo, that is, in the direction of suppressing the vehicle body Bo from being lifted during rolling. (Force F1sv or force F3sv, or resultant force of force F1sv and force F3sv) can be generated.

  In this manner, by controlling the rotation of each motor 6 so that the driving torque or braking torque in the state shown in FIG. Force Fu in the direction (vertical direction in FIG. 5), that is, the direction in which the vehicle body Bo is lifted, that is, the direction in which the body Bo is prevented from sinking when the vehicle body Bo rolls (upward in FIG. 5) It is possible to apply a force Fd in a direction in which Bo is pushed down, that is, a direction in which the body Bo is prevented from being lifted when the body Bo rolls (downward in FIG. 5).

  Returning to FIG. 4, stroke sensors 10 for detecting the stroke amount of each suspension 5 are provided at predetermined positions corresponding to the respective wheels 1, 2, 3, 4 of the vehicle body Bo. Further, a lateral acceleration sensor 11 that detects lateral acceleration generated in the vehicle body Bo is provided at a predetermined position of the vehicle body Bo. Each of the stroke sensor 10 and the lateral acceleration sensor 11 is connected to the ECU 9 and configured to detect a roll state of the vehicle body Bo such as a roll amount or a roll angle based on the detection result. Has been. Accordingly, each of the stroke sensor 10, the lateral acceleration sensor 11, the ECU 9, and the like function as roll detecting means in the present invention. Instead of the stroke sensor 10 described above, for example, a vehicle height sensor (not shown) is placed at a predetermined position corresponding to each wheel 1, 2, 3, 4 of the vehicle body Bo, or a vertical acceleration sensor (not shown). ) At predetermined positions corresponding to the wheels 1, 2, 3, and 4 of the vehicle body Bo, and the roll state of the vehicle body Bo can be detected by detecting or calculating the stroke amount of each suspension 5. is there.

  As described above, each of the suspensions 5 described above with respect to the roll of the vehicle body Bo detected by the roll detection means including the stroke sensor 10, the lateral acceleration sensor 11, the ECU 9, etc. The instantaneous rotation centers C1, C2, C3, and C4 are configured to be positioned between the front wheels 1 and 2 and the rear wheels 3 and 4, respectively, and include the motor 6, the inverter 7, the battery 8, the ECU 9, and the like. By controlling the braking / driving torque control means to be applied, a force Fu in a direction to suppress the sinking of the vehicle body Bo or a force Fd in a direction to suppress the lifting of the vehicle body Bo is applied, so that the roll state of the vehicle body Bo is, for example, It can control appropriately so that it may suppress. Accordingly, the suspensions 5, the motors 6, the inverter 7, the battery 8, the ECU 9, and the like function as roll control means in the present invention.

  Further, wheel speed sensors 12 for detecting the rotational speeds of the respective wheels 1, 2, 3, 4 are provided at predetermined positions corresponding to the respective wheels 1, 2, 3, 4 of the vehicle body Bo. Each wheel speed sensor 12 is connected to the ECU 9 to detect the rotational speed of each wheel 1, 2, 3, 4 and based on the detection result, the speed (vehicle speed) in the front-rear direction of the vehicle body Bo. And the acceleration in the longitudinal direction of the vehicle body Bo (longitudinal acceleration), or the traveling state of the vehicle Ve such as the slip state or the locked state of each wheel 1, 2, 3, 4 can be detected or calculated. Yes. Instead of the wheel speed sensor 12 described above, for example, by detecting a control signal for controlling the rotation of each motor 6 or a current value of electric power supplied to each motor 6, the vehicle speed and the front and rear of the vehicle body Bo are detected. It is also possible to detect acceleration and the like. Further, the longitudinal acceleration of the vehicle body Bo can be detected by providing a longitudinal acceleration sensor (not shown).

  A brake pedal sensor 13 that detects a depression amount (depression angle) or depression pressure of a brake pedal (not shown), and an accelerator that detects an depression amount (depression angle) or depression pressure of an accelerator pedal (not shown). A pedal sensor 14 and a steering angle sensor 15 for detecting the steering direction and the amount of steering angle of the steering wheel are provided. The brake pedal sensor 13, the accelerator pedal sensor 14, and the steering angle sensor 15 are connected to the ECU 9, and detect or calculate the traveling state of the vehicle Ve based on the detection results thereof, and the detection results thereof. Based on the above, each motor 6, or a hydraulic pump (not shown) for power steering or an electric motor (not shown) is appropriately controlled.

  As described above, the present invention provides a sensor / device when performing roll control for controlling the roll state of the vehicle body Bo by individually controlling the driving torque or braking torque applied to each of the wheels 1, 2, 3 and 4. If the vehicle Ve malfunctions, such as a failure of the wheel, a decrease in the filling gas pressure of the tires of the wheels 1, 2, 3, 4 or a phenomenon that the turning inner wheel is lifted during turning, the roll control is in a normal state. The purpose of the present invention is to appropriately control the roll state of the vehicle body Bo by avoiding a decrease in the stability of the behavior of the vehicle Ve, and for this purpose, the control device of the present invention performs the following control. Is configured to run.

  FIG. 1 is a flowchart for explaining an example of control by the control device of the present invention. The routine shown in this flowchart is repeatedly executed every predetermined short time. In FIG. 1, first, roll control is performed to control the driving torque or braking torque applied to each wheel 1, 2, 3, 4 according to the roll state of the vehicle body Bo, and to control the roll state of the vehicle body Bo to a desired state. Whether or not a fail signal is output from various sensors / devices used in execution, such as the motor 6, inverter 7, stroke sensor 10, wheel speed sensor 12, etc., that is, there is an abnormality in these various sensors / devices. It is determined whether or not it has occurred (step S101). If the determination in step S101 is affirmative due to the detection of a fail signal from various sensors / devices, this routine is temporarily terminated without performing the subsequent control. That is, the execution of roll control is prohibited or stopped.

  On the other hand, when a failure signal from various sensors / devices is not detected, that is, when there is no abnormality in the various sensors / devices used when performing roll control, a negative determination is made in step S101. In step S102, the filling gas pressures of the tires of the wheels 1, 2, 3, and 4 are set to predetermined filling gas pressures (normal values) that are predetermined as tire filling gas pressures at which the vehicle Ve can normally travel. It is determined whether it is lower than the lower limit.

  As described above, when the tire filling gas pressure is reduced below the normal value, the tire stiffness is lowered, and the driving torque or braking torque output from each motor 6 of each wheel 1, 2, 3, 4 is changed to each wheel. The control responsiveness when driving force or braking force is generated by being applied to 1, 2, 3, 4 is reduced. If roll control is performed in this state as usual, an unbalance occurs in the magnitude or generation time of the driving force or braking force output from the wheels 1, 2, 3, and 4, for example, an unnecessary moment in the yaw direction. There is a possibility that proper roll control cannot be executed due to occurrence of a moment in the direction of promoting the roll or the like. Therefore, in this step S102, an abnormal state in which the filling gas pressure of the tires of the wheels 1, 2, 3, 4 is lowered is detected.

  Therefore, the filling gas pressure of the tire of each wheel 1, 2, 3, 4 is lower than the predetermined filling gas pressure, that is, the filling gas pressure of the tire of each wheel 1, 2, 3, 4 is abnormally lowered. If the determination in step S102 is affirmative, the routine is temporarily terminated without performing the subsequent control. That is, the execution of roll control is prohibited or stopped.

  On the other hand, the tire filling gas pressure of each wheel 1, 2, 3, 4 is equal to or higher than a predetermined filling gas pressure, that is, the tire filling gas pressure of each wheel 1, 2, 3, 4 is normal. When a negative determination is made in step S12, the process proceeds to step S103, and it is determined whether or not the turning inner wheel load is “0” or less. This is because the roll of the vehicle body Bo becomes large at the time of a sudden turn at a high speed, and the wheel on the turning inner wheel side is lifted from the ground contact surface (road surface), that is, the wheel load on the turning inner wheel side becomes “0” or less. This is control for detecting a so-called inner ring floating state. When the inner ring floats, even if the roll control is executed, the force for controlling the roll state of the vehicle body Bo cannot be transmitted to the road surface, and the appropriate roll control cannot be performed. The state is to be detected.

  Therefore, if the turning inner ring load is “0” or less, that is, if the inner ring floating occurs during turning, affirmative determination is made in step S103, the routine is not performed and this routine is not performed. Is temporarily terminated. That is, the execution of roll control is prohibited or stopped.

  On the other hand, if the turning inner ring load is larger than “0”, that is, the inner ring floating during turning has not occurred, and if the determination in step S103 is affirmative, the process proceeds to the next step, the lateral acceleration sensor 11 or a detected value of the stroke sensor 10 or the like is input to the ECU 9 (step S104). Then, based on those detected values, that is, the lateral acceleration Gy of the vehicle body Bo, or the stroke amount St in each suspension 5 of each wheel 1, 2, 3, 4, the roll angle RA representing the roll state occurring in the vehicle body Bo. Is calculated (step S105).

  When the roll angle RA is calculated, it is determined whether or not the roll angle RA is “0”, that is, whether or not a roll is generated in the vehicle body Bo (step S106). If the roll angle RA is “0”, that is, no roll is generated in the vehicle body Bo, and if it is determined affirmatively in this step S16, it is not necessary to perform roll control. This routine is temporarily terminated.

  On the other hand, if the roll angle RA is not “0”, that is, if the roll is generated in the vehicle body Bo, a negative determination is made in step S106, the process proceeds to step S107, where the roll angle is less than “0”. It is determined whether or not it is large. This is a determination step for detecting the direction of the roll generated in the vehicle body Bo based on whether the roll angle RA is positive or negative. In this control example, the left side of the vehicle body Bo (the wheels 1 and 3 side) is lifted up. The roll angle RA at which the right side of Bo (wheels 2 and 4 side) sinks is set as a positive direction, and on the contrary, the right side of vehicle body Bo (wheels 2 and 4 side) is lifted, and the left side of vehicle body Bo (wheels 1 and 2) The roll angle RA in which the (3 side) sinks is in the negative direction.

  Therefore, if the roll angle RA is larger than “0”, that is, if the roll is generated in the vehicle body Bo at the roll angle RA in the positive direction, if the determination in step S107 is affirmative, Proceeding to S108, the torque ΔTr obtained according to the magnitude of the roll angle RA is increased to the driving torque of the left front wheel 1 and is decreased from the driving torque of the left rear wheel 3. In other words, a driving torque ΔTr for roll control is applied to the left front wheel 1, and a braking torque ΔTr for roll control is applied to the left rear wheel 3. That is, a vertical downward force (force Fd shown in FIG. 5 (b) described above) for suppressing the lifting of the left side of the vehicle body Bo (wheels 1 and 3) is applied to the vehicle body Bo. Driving torque ΔTr is applied, and braking torque ΔTr is applied to the left rear wheel 3.

  At the same time, the torque ΔTr is decreased from the driving torque of the right front wheel 2 and is increased to the driving torque of the right rear wheel 4 (step S109). In other words, the braking torque ΔTr for roll control is applied to the right front wheel 2, and the driving torque ΔTr for roll control is applied to the right rear wheel 4. That is, in order to apply a vertically upward force (force Fu shown in FIG. 5A) for suppressing the sinking of the right side of the vehicle body Bo (wheels 2 and 4) to the vehicle body Bo, the right front wheel 2 Braking torque ΔTr is applied to the right rear wheel 4 and driving torque ΔTr is applied to the right rear wheel 4. Thereafter, this routine is once terminated.

  On the other hand, when the roll angle RA is smaller than “0”, that is, when the roll is generated in the vehicle body Bo at the negative roll angle RA, the determination is negative in step S107. Advances to step S110, and the torque ΔTr obtained according to the magnitude of the roll angle RA is increased to the driving torque of the right front wheel 2 and is decreased from the driving torque of the right rear wheel 4. In other words, a driving torque ΔTr for roll control is applied to the right front wheel 2, and a braking torque ΔTr for roll control is applied to the right rear wheel 4. That is, a driving torque ΔTr is applied to the right front wheel 2 and a braking torque is applied to the right rear wheel 4 in order to apply a vertically downward force to the vehicle body Bo to suppress the lifting of the right side of the vehicle body Bo (wheels 2 and 4 side). ΔTr is given.

  At the same time, the torque ΔTr is decreased from the driving torque of the left front wheel 1 and increased to the driving torque of the left rear wheel 3 (step S111). In other words, the braking torque ΔTr for roll control is applied to the left front wheel 1, and the drive torque ΔTr for roll control is applied to the left rear wheel 3. That is, a braking torque ΔTr is applied to the left front wheel 1 to drive the left rear wheel 3 in order to apply a vertical upward force to the vehicle body Bo to suppress the sinking of the left side of the vehicle body Bo (wheels 1 and 3 side). Torque ΔTr is applied. Thereafter, this routine is once terminated.

  FIG. 2 is a flowchart for explaining another control example by the control device of the present invention. Like the control example shown in FIG. 1, the routine shown in the flowchart of FIG. Repeated every time. Further, the same control steps as the control contents in the flowchart of FIG. 1 are denoted by the same reference numerals (step numbers) as those in the flowchart of FIG. 1, and detailed description of the control contents is omitted. The above-described control example shown in FIG. 1 is an example of performing control so as to prohibit execution of roll control when the filling gas pressure of the wheel tire is lower than a predetermined filling gas pressure (lower limit of normal value). On the other hand, in the control example shown in FIG. 2, when the filling gas pressure of the tire of the wheel is lower than a predetermined filling gas pressure, the drive applied to each wheel 1, 2, 3, 4 for roll control. This is an example of controlling to reduce the magnitude of torque or braking torque.

  That is, in FIG. 2, first, the filling gas pressures of the tires of the respective wheels 1, 2, 3, and 4 are predetermined predetermined filling gas pressures (normal values) that are predetermined as tire filling gas pressures at which the vehicle Ve can travel normally. It is determined whether it is lower than (lower limit) (step S201). This step is performed when the filling gas pressure of the tire of each wheel 1, 2, 3, 4 is equal to or higher than the predetermined filling gas pressure, that is, the filling gas pressure of the tire of each wheel 1, 2, 3, 4 is normal. When a negative determination is made in S201, the process proceeds to step S103 in the flowchart of FIG. 1 described above, and the subsequent control is similarly executed.

  On the other hand, if it is determined affirmative in step S201 because the filling gas pressure of the tires of the wheels 1, 2, 3, 4 is lower than the predetermined filling gas pressure, the process proceeds to step S202. A reduction rate α for reducing the magnitude of the driving torque or braking torque applied to each wheel 1, 2, 3, 4 for roll control is required. This reduction rate α can be determined empirically and experimentally according to the degree of decrease in the filling gas pressure of the tires of the wheels 1, 2, 3 and 4, for example, a map set empirically and experimentally. Or based on a calculation formula or the like.

  Subsequently, when the control in steps S104 to S107 is executed in the same manner as in the control example shown in FIG. 1 described above, and the roll angle RA is larger than “0”, so that a positive determination is made in step S107. Advances to step S203, and the value obtained by multiplying the torque ΔTr obtained according to the magnitude of the roll angle RA by the reduction rate α is increased to the driving torque of the left front wheel 1, and is decreased from the driving torque of the left rear wheel 3. The In other words, a driving torque “ΔTr × α” for roll control is applied to the left front wheel 1, and a braking torque “ΔTr × α” for roll control is applied to the left rear wheel 3. That is, a vertical downward force (force Fd shown in FIG. 5 (b) described above) for suppressing the lifting of the left side of the vehicle body Bo (wheels 1 and 3) is applied to the vehicle body Bo. Driving torque “ΔTr × α” is applied, and braking torque “ΔTr × α” is applied to the left rear wheel 3.

  In addition, the torque “ΔTr × α” is decreased from the driving torque of the right front wheel 2 and increased to the driving torque of the right rear wheel 4 (step S204). In other words, the braking torque “ΔTr × α” for the roll control is applied to the right front wheel 2, and the driving torque “ΔTr × α” for the roll control is applied to the right rear wheel 4. That is, in order to apply a vertically upward force (force Fu shown in FIG. 5A) for suppressing the sinking of the right side of the vehicle body Bo (wheels 2 and 4) to the vehicle body Bo, the right front wheel 2 The braking torque “ΔTr × α” is applied to the right rear wheel 4 and the driving torque “ΔTr × α” is applied to the right rear wheel 4. Thereafter, this routine is once terminated.

  On the other hand, if the roll angle RA is smaller than “0” and a negative determination is made in step S107, the process proceeds to step S205, where the torque ΔTr obtained according to the magnitude of the roll angle RA is set. A value multiplied by the reduction rate α is increased to the driving torque of the right front wheel 2 and is decreased from the driving torque of the right rear wheel 4. In other words, a driving torque “ΔTr × α” for roll control is applied to the right front wheel 2, and a braking torque “ΔTr × α” for roll control is applied to the right rear wheel 4. That is, in order to apply a vertical downward force to the vehicle body Bo to suppress the lifting of the right side of the vehicle body Bo (wheels 2 and 4 side), a driving torque “ΔTr × α” is applied to the right front wheel 2 and the right rear wheel 4 is applied with a braking torque “ΔTr × α”.

  In addition, the torque “ΔTr × α” is decreased from the driving torque of the left front wheel 1 and increased to the driving torque of the left rear wheel 3 (step S206). In other words, the braking torque “ΔTr × α” for roll control is applied to the left front wheel 1, and the driving torque “ΔTr × α” for roll control is applied to the left rear wheel 3. That is, the braking torque “ΔTr × α” is applied to the left front wheel 1 in order to apply a vertical upward force to the vehicle body Bo to suppress the sinking of the vehicle body Bo left side (wheels 1 and 3 side). A driving torque “ΔTr × α” is applied to the wheel 3. Thereafter, this routine is once terminated.

  FIG. 3 is a flowchart for explaining still another control example by the control device of the present invention. Like the control examples shown in FIGS. 1 and 2, the routine shown in the flowchart of FIG. It is repeatedly executed every short time. The above-described control example shown in FIG. 1 is an example of performing control so as to prohibit the execution of roll control when the filling gas pressure of the wheel tire is lower than a predetermined filling gas pressure (lower limit of normal value), In the control example shown in FIG. 2 described above, when the filling gas pressure of the wheel tire is lower than a predetermined filling gas pressure (the lower limit of the normal value), each wheel 1, 2, 3, 4 is used for roll control. In the control example shown in FIG. 3, the filling gas pressure of the wheel tire is lower than the predetermined filling gas pressure, whereas the driving torque or the braking torque to be applied is controlled to be reduced. In this case, it is possible to identify an abnormal wheel whose tire filling air pressure is low and apply a driving torque or a braking torque to the abnormal wheel, and a control to apply a driving torque or a braking torque to an abnormal wheel. Set a delay time Te is an example of controlling so as to eliminate the imbalance of the response of the control.

  That is, in FIG. 3, first, the filling gas pressures of the tires of the respective wheels 1, 2, 3, and 4 are predetermined predetermined filling gas pressures (normal values) that are predetermined as tire filling gas pressures at which the vehicle Ve can travel normally. It is determined whether it is lower than (lower limit) (step S301). This step is performed when the filling gas pressure of the tire of each wheel 1, 2, 3, 4 is equal to or higher than the predetermined filling gas pressure, that is, the filling gas pressure of the tire of each wheel 1, 2, 3, 4 is normal. When a negative determination is made in S301, the process proceeds to step S103 in the flowchart of FIG. 1 described above, and the subsequent control is similarly executed.

  On the other hand, when it is determined affirmative in step S301 because the filling gas pressure of the tire of each wheel 1, 2, 3, 4 is lower than the predetermined filling gas pressure, the process proceeds to step S302. A reduction rate that reduces the magnitude of the driving torque or braking torque applied to each wheel 1, 2, 3, 4 for roll control by identifying a wheel whose tire filling gas pressure is lower than a predetermined filling gas pressure α is obtained (step S303).

  Subsequently, when applying driving torque and braking torque to each of the wheels 1, 2, 3, and 4 for roll control, the wheel filled with the tire filling gas pressure is lower than the predetermined filling gas pressure. Control for applying a driving torque or braking torque for roll control to a normal wheel whose tire filling gas pressure is not lower than a predetermined filling gas pressure. A delay time ΔT for delaying by a predetermined time is obtained (step S304). This delay time ΔT can be obtained empirically and experimentally according to the degree of decrease in the filling gas pressure of the tires of the wheels 1, 2, 3, and 4, for example, a map set empirically and experimentally. Or based on a calculation formula or the like.

  When the delay time ΔT is obtained, the process proceeds to step S305, and the control for applying the driving torque or the braking torque for the roll control to the normal wheel in which the tire filling gas pressure is not reduced is set to the delay time ΔT. Executed. In this case, the control for applying the driving torque or the braking torque for the roll control to each of the wheels 1, 2, 3 and 4 is the control content in steps S106 to S111 of the flowchart of FIG. It is executed in the same manner as the control contents in steps S106, S107, S203 to S206. Thereafter, this routine is once terminated.

  As described above, according to the control device of the present invention, the driving torque or braking torque applied to each wheel 1, 2, 3, 4 is independently controlled, and the vehicle body Bo is moved up and down via the suspension 5. Roll force control for controlling the roll state of the vehicle body Bo is executed by applying a directional force. At this time, for example, a failure of various sensors and devices such as sensors and actuators used for roll control, a decrease in filling air pressure of tires of the respective wheels 1, 2, 3 and 4, or a so-called inner ring floating state during turning When an abnormality such as the above is detected, the control content of the roll control is appropriately changed. For example, the magnitudes of driving torque and braking torque applied to each wheel 1, 2, 3, 4 for roll control are reduced. Or execution of roll control is prohibited. Therefore, even when the above-described abnormality occurs in the vehicle Ve at the time of executing the roll control, it is possible to avoid the roll control being continued as usual and the stability of the behavior of the vehicle Ve being reduced. .

  Further, when the roll control is executed, the tire filling gas pressure of each of the wheels 1, 2, 3, and 4 is lower than a predetermined filling gas pressure that is predetermined as the tire filling gas pressure in a normal state. When it is detected that the vehicle is running, the driving torque and braking torque applied to each of the wheels 1, 2, 3, and 4 for executing the roll control are reduced. Or execution of roll control is prohibited. When the tire filling gas pressure is reduced, the tire stiffness is lowered, and the responsiveness of the grip force when driving torque or braking torque is applied to the wheels 1, 2, 3, 4 is lowered. Therefore, when roll control is executed in this state, an imbalance of control responsiveness occurs between a wheel having a reduced tire filling gas pressure and a wheel having a normal tire filling gas pressure, and appropriate roll control is performed. However, when the filling gas pressure of the tires of the wheels 1, 2, 3, and 4 is lower than a predetermined filling gas pressure, the wheels 1, 2, and 3 are used to execute the roll control. When the driving torque and braking torque applied to 3 and 4 are reduced, or execution of roll control is prohibited, inappropriate roll control is continued and the stability of the behavior of the vehicle is lowered. This can be avoided or suppressed.

  Further, when the roll control is executed, if it is detected that the filling gas pressure of the tire of each of the wheels 1, 2, 3, 4 is lower than a predetermined filling gas pressure, the tire In contrast to roll control that applies driving torque or braking torque to a wheel in which a decrease in filling gas pressure is detected, roll control that applies driving torque or braking torque to a wheel with normal tire filling gas pressure is It is executed with a delay time ΔT. When roll control is executed in a state where the filling gas pressure of one of the tires is reduced, the control responsiveness between the wheel where the tire filling gas pressure is reduced and the wheel where the tire filling gas pressure is normal is reduced. An imbalance may occur, i.e., there may be a time difference in the response of the roll control, but if any tire fill gas pressure is reduced below a predetermined fill gas pressure, the tire fill gas pressure is relative to a normal wheel. By executing the roll control with a predetermined delay time ΔT, the imbalance in control responsiveness is eliminated, and improper roll control is continued, resulting in a decrease in the stability of the vehicle behavior. It can be avoided or suppressed.

  The suspension 5 that supports the wheels 1, 2, 3, and 4 on the vehicle body Bo is such that the instantaneous rotation centers C1, C2, C3, and C4 in the side view of the vehicle Ve are always the front wheels 1 and 2 in the longitudinal direction of the vehicle Ve. Between the front wheels 1 and 2 and the rear wheels 3 and 4, and by providing a difference in the magnitude or direction of the torque applied to the front wheels 1 and 2 and the rear wheels 3 and 4, The force is applied. Therefore, the driving torque or braking torque to be applied to the front wheels 1 and 2 and the driving torque or braking torque to be applied to the rear wheels 3 and 4 are provided with at least a difference therebetween, in other words, they are different from each other. By controlling to an arbitrary magnitude, the vertical force acting on the vehicle body Bo can be arbitrarily set, and roll control can be easily executed.

  In addition, since the torque applied to each wheel 1, 2, 3, 4 is controlled by independently controlling the rotation of the motor 6 incorporated in each wheel 1, 2, 3, 4, respectively, Roll control can be executed easily.

  Here, the relationship between the above-described specific example and the present invention will be briefly described. The functional means of steps S101 to S103, S201, S301, and S302 described above correspond to the vehicle abnormality detection means of the present invention. The functional means in steps S106 to S111 correspond to the roll control means of the present invention. The functional means of steps S101 to S103, S201 to S206, and S301 to S305 correspond to the roll control changing means of the present invention.

  Note that the present invention is not limited to the above specific example. In the specific example, as means for independently controlling the driving torque and the braking torque of each wheel, a motor disposed inside each wheel, that is, each Although an example in which the driving torque and the braking torque are output by controlling the rotation of a so-called in-wheel motor incorporated in the wheel of the wheel is shown, other than this specific example, for example, the vehicle body corresponding to each wheel The mechanism may be such that the output of the motor installed in is transmitted to each wheel via a drive shaft or the like, and the driving torque of each wheel is controlled independently. Further, for example, a mechanism (for example, a torque split mechanism) that can variably distribute the power output from a power source such as a motor or an internal combustion engine for each wheel can be employed. As a means for independently controlling the braking torque of each wheel, it is possible to employ a mechanism that can automatically control the braking device provided for each wheel separately from the braking operation by the occupant.

  Further, in the above specific example, an example in which the roll state of the vehicle body that occurs at the time of turning is an object of control is shown. However, for example, the roll of the vehicle body caused by other factors such as road surface unevenness and strong wind (crosswind) The state can also be controlled.

It is a flowchart for demonstrating the example of control by the control apparatus of this invention. It is a flowchart for demonstrating the other control example by the control apparatus of this invention. It is a flowchart for demonstrating the further another example of control by the control apparatus of this invention. 1 is a conceptual diagram schematically showing a configuration and a control system of a vehicle to which a control device of the present invention can be applied. It is a schematic diagram for explaining each instantaneous rotation center of a suspension mechanism in a vehicle having a configuration to which the control device of the present invention can be applied, and forces and behaviors acting on each part of the vehicle when roll control is executed.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1, 2 ... Front wheel, 3, 4 ... Rear wheel, 5 ... Suspension, 6 ... Motor (in-wheel motor), 7 ... Inverter, 8 ... Battery, 9 ... Electronic control unit (ECU), 10 ... Stroke sensor, 11 ... Lateral acceleration sensor, 12 ... wheel speed sensor, 13 ... brake pedal sensor, 14 ... accelerator pedal sensor, 15 ... rudder angle sensor, Ve ... vehicle, Bo ... vehicle body.

Claims (6)

A suspension mechanism for independently supporting at least the front and rear wheels on the vehicle body, braking / driving torque control means for independently controlling the driving torque and braking torque of the front and rear wheels, and roll detection means for detecting the roll state of the vehicle body; And a roll control unit that applies a driving torque or a braking torque to the front and rear wheels by the braking / driving torque control unit according to the roll state detected by the roll detection unit, and controls the roll state. In the control device,
Vehicle abnormality detection means for detecting an abnormality of the vehicle;
A vehicle control apparatus comprising: a roll control changing unit that changes the control content of the roll state by the roll control unit when an abnormality of the vehicle is detected by the vehicle abnormality detection unit. The vehicle abnormality detecting means includes means for detecting whether or not the filling gas pressure of the front and rear tires is lower than a predetermined filling gas pressure,
The roll control change means controls the roll state when the vehicle abnormality detection means detects that the filling gas pressure of any of the front and rear tires is lower than a predetermined filling gas pressure. The vehicle control device according to claim 1, further comprising means for reducing driving torque or braking torque applied to the front and rear wheels. The vehicle abnormality detection means detects a filling gas pressure of the tires of the front and rear wheels, determines whether or not the pressure is lower than a predetermined filling gas pressure, and identifies a wheel where the filling gas pressure has decreased. Including means,
The roll control change unit is configured to drive torque to a wheel in which a decrease in the filling gas pressure of the tire is detected when the vehicle abnormality detection unit detects a decrease in the filling gas pressure of one of the front and rear wheels. Alternatively, with respect to the control of the roll state for applying the braking torque, the control of the roll state for applying the driving torque or the braking torque to the wheel in which the decrease in the filling gas pressure of the tire is not detected is performed with a predetermined delay time. The vehicle control device according to claim 1, further comprising means for providing and executing the vehicle control device. The vehicle abnormality detection means includes means for detecting an abnormality of a device used for controlling the roll state,
2. The vehicle according to claim 1, wherein the roll control change unit includes a unit that prohibits execution of control of the roll state when an abnormality of the device is detected by the vehicle abnormality detection unit. Control device. The suspension mechanism is configured such that an instantaneous rotation center in a side view of the vehicle is located between the front wheel and the rear wheel,
2. The roll control means includes means for controlling the roll state by providing a difference in driving torque or braking torque between the front wheels and rear wheels applied by the braking / driving torque control means. 5. The vehicle control device according to any one of 4 to 4.   6. The braking / driving torque control means includes means for controlling the driving torque and braking torque by controlling the rotation of an electric motor that independently applies torque to the front and rear wheels, respectively. The vehicle control device according to any one of the above.

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