JP4884064B2 - Vehicle state detection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that a vehicle is detected to be in an understeer state even if a driver returns a steering wheel, in a vehicular state detecting device using road surface reaction torque. <P>SOLUTION: The vehicular state detecting device detects actual road surface reaction torque which a vehicular tire receives from a road surface by a road surface reaction torque detecting means 101, computes standard road surface reaction torque by a standard road surface reaction torque computing means 102 on the basis of a traveling state of a vehicle, detects a steering state of a driver driving a vehicle by a steering state detecting means 103, and detects an unstable behavior state of the vehicle by a vehicular behavior state detecting means 104 on the basis of the output of the road surface reaction torque detecting means and the output of the standard road surface reaction computing means. When the steering state detecting means detects that the steering state of the driver is returning, the detection of the unstable behavior state of the vehicle by the vehicular behavior state detecting means is prohibited. <P>COPYRIGHT: (C)2008,JPO&amp;INPIT

Description

  The present invention relates to a vehicle state detection device that detects an unstable behavior state such as understeer of a running vehicle.

  A conventional vehicle state detection device that detects an unstable behavior state such as understeer of a running vehicle is a side slip angle measuring device that detects an actual side slip angle, and a standard that calculates a standard alignment torque that corresponds to a standard road surface reaction force torque An alignment torque calculator, an alignment torque measuring device that detects an actual alignment torque corresponding to the actual road surface reaction torque received by the running vehicle from the road surface, and an absolute value of the deviation between the actual alignment torque and the reference alignment torque An alignment torque deviation calculator that calculates the deviation, and a vehicle behavior stability discriminator that compares the alignment torque deviation with a predetermined amount and determines that the vehicle behavior is unstable when the alignment torque deviation is equal to or larger than the predetermined amount. The absolute value of the deviation between the standard alignment torque and the actual alignment torque It is as in determining the instability of the vehicle during traveling with. (For example, see Patent Document 1)

JP 2003-341538 A

  In the conventional vehicle state detection device, the absolute value of the deviation between the reference alignment torque and the actual alignment torque is used to determine the unstable behavior state of the running vehicle. Therefore, although it is possible to determine understeer in a simple unstable state estimated from the deviation between the reference alignment torque and the actual alignment torque, understeer is detected even when the driver is turning back the steering wheel. There was a risk of misjudgment. Moreover, if understeer is suppressed based on erroneous determination, there is a problem that the vehicle's rotational movement is promoted.

The present invention has been made to solve such a problem in the conventional vehicle state detection device, and provides a vehicle state detection device that can accurately detect an understeer state of a vehicle without erroneous determination. The purpose is to do.

The vehicle state detection device according to the present invention includes road surface reaction force torque detecting means for detecting an actual road surface reaction force torque received by a vehicle tire from the road surface, and a reference road surface reaction in the traveling state based on the traveling state of the vehicle. Reference road surface reaction force torque calculation means for calculating force torque, steering state detection means for detecting the steering state of the driver who drives the vehicle, output of the road surface reaction force torque detection means, and reference road surface reaction force calculation means Vehicle behavior state detection means for detecting an understeer state of the vehicle based on the output of the vehicle, and the absolute value of the deviation between the output of the reference road surface reaction force torque calculation means and the output of the road surface reaction force torque detection means is greater than a threshold value , when said steering state detecting section determines that a state where no switch back the steering state of the driver, the under of the vehicle by the vehicle behavior state detecting means It is obtained to detect the steering state.

Further, the vehicle state detection device according to the present invention includes a road surface reaction force torque detecting means for detecting an actual road surface reaction force torque received by a vehicle tire from the road surface, and a norm in the traveling state based on the traveling state of the vehicle. It is determined whether the reference road surface reaction torque calculating means for calculating the road surface reaction force torque and the output direction of the road surface reaction force torque detecting means are the same as the output direction of the reference road surface reaction torque calculation means. Road surface reaction force direction determination means, vehicle behavior state detection means for detecting an understeer state of the vehicle based on an output of the road surface reaction force torque detection means and an output of the reference road surface reaction force calculation means, the reference road surface absolute value greater than the threshold value of the output deviation of the output and the road surface reaction torque detecting means of the reaction force torque calculation means, the road surface reaction force direction determination means, towards the output of the road surface reaction torque detecting means When the direction of the output of the reference road surface reaction torque calculating means determines that match the is obtained to detect the understeer of the vehicle by the vehicle behavior state detection means.

Further, the vehicle state detection device according to the present invention includes a road surface reaction force torque detecting means for detecting an actual road surface reaction force torque received by a vehicle tire from the road surface, and a norm in the traveling state based on the traveling state of the vehicle. Reference road surface reaction torque calculation means for calculating road reaction force torque, hand release state determination means for determining the release state of the handle of the driver who drives the vehicle, output of the road surface reaction force torque detection means, and the reference road surface Vehicle behavior state detection means for detecting an understeer state of the vehicle based on the output of the reaction force calculation means, and an absolute value of a deviation between the output of the reference road surface reaction torque calculation means and the output of the road surface reaction force torque detection means There greater than the threshold, when the hands-off state determination means determines not to be let go state of said handle, said Anne of the vehicle by the vehicle behavior state detecting means Sutea is obtained to detect the.

According to the vehicle state detecting device according to the present invention, when the steering state detecting section determines that a state where no switch back the steering state of the driver, understeer of the vehicle by the vehicle behavior state detecting means since so as to detect, it can be detected without any precise understeer of the vehicle to misjudgment.

According to the vehicle state detection device of the present invention, the road surface reaction force direction determination means matches the output direction of the road surface reaction force torque detection means with the output direction of the reference road surface reaction force torque calculation means. and as when it is determined by, so was to detect the understeer of the vehicle by the vehicle behavior state detecting means can be detected without any precise understeer of the vehicle to misjudgment.

Furthermore, according to the vehicle state detection device of the present invention, when the hand release state determination unit determines that the handle is not released, the vehicle behavior state detection unit detects the understeer of the vehicle. Therefore, it is possible to accurately detect the understeer state of the vehicle without erroneous determination.

Embodiment 1 FIG.
FIG. 1 is a block diagram showing a vehicle state detection apparatus according to Embodiment 1 of the present invention. In the following description of the first embodiment, detection of understeer as an unstable state of the vehicle will be described. In FIG. 1, a road surface reaction force torque detecting means 101 detects an actual road surface reaction force torque that a vehicle tire receives from a road surface.

  The reference road surface reaction torque calculating means 102 calculates a reference road surface reaction torque, which is an ideal road reaction force torque, from the amount of travel state of the vehicle. The steering state determination unit 103 determines the steering state of the driver. The vehicle behavior state detection unit 104 receives signals from the road surface reaction force torque detection unit 101, the standard road surface reaction torque calculation unit 102, and the steering state determination unit 103, and detects the vehicle behavior state.

  The road surface reaction force torque detecting means 101 may be configured by using a well-known technique. For example, as shown in Japanese Patent Application Laid-Open No. 2005-324737, from the steering torque of the driver and the assist torque of the electric power steering, The actual road surface reaction torque may be estimated, or the actual road surface reaction torque may be directly measured using a load cell or the like.

  The standard road surface reaction torque calculation means 102 may be configured by using a well-known technique. For example, as disclosed in Japanese Patent Application Laid-Open No. 2005-324737, the steering wheel angle, the traveling speed of the vehicle, and the standard road surface reaction. You may comprise so that a reference | standard road surface reaction force torque may be calculated from the map of the handle | steering-wheel angle / travel speed and reference | standard road surface reaction force torque in which the relationship with force torque was described.

  The detection results and calculation results of the road surface reaction torque detection means 101, the standard road surface reaction torque calculation means 102, the steering state determination means 103, and the vehicle behavior state detection means 104 are stored in a memory (not shown). .

  Next, the operation of the vehicle state detection apparatus according to the first embodiment will be described based on the flowchart shown in FIG. When the program starts, first, in step S101, the steering angle is detected by the steering state detection means 103, and the detection result is stored in the memory. Next, proceeding to step S102, the steering torque is similarly detected by the steering state detection means 103, and the detection result is stored in the memory.

  Next, proceeding to step S103, the road surface reaction torque detection means 101 detects the actual road surface reaction torque, and the detection result is stored in the memory. In step S104, the reference road surface reaction torque is calculated by the reference road surface reaction torque detection means 102, and the detection result is stored in the memory.

  Next, proceeding to step S105, the absolute value of the road surface reaction force torque deviation, which is the deviation between the actual road surface reaction force torque stored in the memory and the reference road surface reaction force torque, is calculated, and the calculation result is stored in the memory. Next, in step S106, it is determined whether or not the absolute value of the road surface reaction force torque deviation calculated in step S105 is larger than a threshold value. If the absolute value of the road surface reaction force torque deviation is larger than the threshold value (Yes). Advances to step S107, and if smaller than the threshold (No), returns to the start.

  If it is determined in step S107 whether or not the driver's operation is in the switchback state based on the steering angle and the steering torque stored in the memory, and it is detected that the driver switches back the steering wheel (Yes) Returns to the start, and if it is determined that the driver's operation is not switched back (No), the process proceeds to step S108. In step S108, an understeer detection flag is output and the program operation is terminated.

  The determination in step S107 may be performed by detecting the steering wheel angle and the steering torque that the driver steers and by determining the product of the sign of the steering angle and the steering torque, or by using known techniques such as the steering angle and the steering angular velocity. It may be used to determine whether the steering state is increased, maintained, or switched back.

  According to the vehicle state detection device according to the first embodiment described above, when the absolute value of the road surface reaction torque deviation, which is the deviation between the standard road surface reaction torque and the actual road surface reaction torque, is larger than the threshold, It is determined whether or not the steering state is reversing, and when it is determined that reversing, understeer detection is prohibited, thereby detecting understeer when the driver is reversing the steering wheel. A misjudgment is prevented, and an accurate vehicle state can be detected.

Embodiment 2. FIG.
FIG. 3 is a block diagram showing a vehicle state detection apparatus according to Embodiment 2 of the present invention. In FIG. 3, a road surface reaction force torque detecting means 201 detects an actual road surface reaction force torque received by a vehicle tire from the road surface. The reference road surface reaction torque calculating unit 202 calculates a reference road surface reaction force torque, which is an ideal road surface reaction force torque, from the running state quantity of the vehicle. The road surface reaction force direction determination unit 203 determines the direction of the road surface reaction force torque based on the signal from the road surface reaction force torque detection unit 201 and the signal from the reference road surface reaction force torque calculation unit 202.

  The vehicle behavior state detection means 204 is based on the signal from the road surface reaction force torque detection means 201, the signal from the reference road surface reaction force torque calculation means 202, and the signal from the road surface reaction force direction determination means 203. Is detected. The respective detection results and calculation results by the road surface reaction force torque detection means 201, the reference road surface reaction torque calculation means 202, and the road surface reaction force direction determination means 203 are stored in a memory (not shown).

  The road surface reaction force torque detecting means 201 may be configured by using a well-known technique. For example, as shown in Japanese Patent Application Laid-Open No. 2005-324737, from the steering torque of the driver and the assist torque of the electric power steering, The actual road surface torque may be estimated, or the actual road surface torque may be directly measured using a load cell or the like.

  The standard road surface reaction torque calculation means 202 may be configured using a well-known technique. For example, as disclosed in JP-A-2005-324737, the steering wheel angle, the vehicle traveling speed, and the standard road surface reaction are described. You may comprise so that a reference | standard road surface reaction force torque may be calculated from the map of the handle | steering-wheel angle / travel speed and reference | standard road surface reaction force torque in which the relationship with force torque was described.

  Next, the operation of the vehicle state detection apparatus according to the second embodiment will be described based on the flowchart shown in FIG. When the program starts, first, in step S201, the road surface reaction torque detection means 201 detects the actual road surface reaction torque and stores it in the memory. In step S202, the reference road surface reaction torque is calculated by the reference road surface reaction torque calculating means 202 and stored in the memory.

  Next, proceeding to step S203, the absolute value of the road surface reaction torque deviation, which is the deviation between the actual road surface reaction torque stored in the memory and the reference road surface reaction torque, is calculated and stored in the memory, and the road surface reaction force is calculated. It is determined whether or not the absolute value of the torque deviation is larger than the threshold value. If the absolute value of the road surface reaction force torque deviation is larger than the threshold value (Yes), the process returns to the start.

  In step S204, the road surface reaction force direction determination means 203 determines whether or not the actual road surface reaction torque stored in the memory and the output direction of the reference road surface reaction torque coincide with each other. As a result of the determination, when the directions of the actual road surface reaction force torque and the standard road surface reaction force torque match (Yes), the process proceeds to step S205 to output the understeer detection flag, and the output directions do not match ( No) returns to the start.

  FIG. 5 is a block diagram illustrating a configuration of the road surface reaction force direction determination unit 203. The road surface reaction force direction determination means 203 multiplies the reference road surface reaction force torque and the actual road surface reaction force torque by the multiplier 301, and compares the multiplied result with “0” by the comparator 302. For example, it is determined that the directions of the standard road surface reaction torque and the actual road surface reaction torque are the same.

  FIG. 6 is a flowchart of the road surface reaction force direction determination operation in the road surface reaction force determination means 203, which corresponds to the step S206 in FIG. In FIG. 6, when the program starts, first, in step S301, the multiplier 301 multiplies the reference road surface reaction torque stored in the memory by the actual road surface reaction torque stored in the memory, and calculates the product. . Next, the process proceeds to step S302, where the comparator 302 compares whether or not the multiplied product value is greater than “0”. If the comparison result is greater than “0”, the reference road surface reaction torque and the actual road surface are compared. It is determined that the direction of the reaction torque is the same.

  According to the vehicle state detection device according to the second embodiment, when the absolute value of the road surface reaction torque deviation, which is the deviation between the standard road surface reaction torque and the actual road surface reaction torque, is larger than the threshold value, Since the direction of the actual road surface reaction torque is determined and understeer is detected only when these torques are in the same direction, the direction of the normal road surface reaction torque and the direction of the actual road surface reaction torque do not match. Therefore, it is possible to eliminate the erroneous determination of detecting understeer and to accurately detect the vehicle state.

Embodiment 3 FIG.
FIG. 7 is a block diagram showing a vehicle state detection apparatus according to Embodiment 3 of the present invention. In FIG. 7, the road surface reaction torque detection means 401 detects the actual road surface reaction torque received by the vehicle tire from the road surface. The reference road surface reaction torque calculating means 402 calculates a reference road surface reaction force torque that is an ideal road surface reaction force torque from the running state quantity of the vehicle. The release state determination unit 403 detects a state in which the driver releases his / her hand from the steering wheel. The vehicle behavior state detection unit 404 detects the state of the vehicle behavior based on outputs from the road surface reaction force torque detection unit 401, the standard road surface reaction force torque calculation unit 402, and the release state determination unit 403.

  The detection results and calculation results of the road surface reaction torque detection means 401, the standard road surface reaction torque calculation means 402, the hand release state determination means 403, and the vehicle behavior state detection means 404 are stored in a memory (not shown). Remembered.

  The road surface reaction force torque detecting means 401 may be configured by using a well-known technique. For example, as shown in Japanese Patent Application Laid-Open No. 2005-324737, from the steering torque of the driver and the assist torque of the electric power steering, The actual road surface torque may be estimated, or the actual road surface torque may be directly measured using a load cell or the like.

  Further, the standard road surface reaction torque calculation means 402 may be configured by using a well-known technique. For example, as disclosed in Japanese Patent Application Laid-Open No. 2005-324737, the steering wheel angle, the vehicle traveling speed, and the standard road surface reaction. You may comprise so that a reference | standard road surface reaction force torque may be calculated from the map of the handle | steering-wheel angle / travel speed and reference | standard road surface reaction force torque in which the relationship with force torque was described.

  Next, the operation of the third embodiment will be described based on the flowchart of FIG. In step S401, the road surface reaction torque detecting means 401 detects the actual road surface reaction force torque, and the detection result is stored in the memory. Next, in step S402, the reference road surface reaction torque calculation means 402 calculates the reference road surface reaction force torque, and the calculation result is stored in the memory. Next, proceeding to step S403, the absolute value of the road surface reaction torque deviation, which is the deviation between the actual road surface reaction torque stored in the memory and the reference road surface reaction torque, is calculated, and the calculation result is stored in the memory. It is determined whether or not the absolute value of the road surface reaction force torque deviation is greater than a threshold value.

  If the absolute value of the road reaction force torque deviation calculated in step S403 is larger than the threshold (Yes), the process proceeds to step S404, and if smaller than the threshold (No), the process returns to the start. In step S404, it is determined whether or not the hand release state determination means 403 is in the release state where the operator has released the handle. If it is determined that the release state is not the release state (No), the process proceeds to step S405 and the release is performed. When it determines with it being in a state (Yes), it returns to a start. In step S405, an understeer detection flag is output.

  FIG. 9 is a block diagram showing a configuration of the hand release state determination unit 403. In the hand-off state determination unit 403, the actual road surface reaction torque detected by the road surface reaction force torque detection unit 401 and the friction torque of the steering mechanism are compared by a comparator 501, and the actual road surface reaction torque is less than the friction torque of the steering mechanism. If so, it is determined that the hand is released.

  FIG. 10 is a flowchart of the release state determination operation by the release state determination unit 403, which corresponds to the step S404 in FIG. When the program starts, first, the actual road surface reaction force torque stored in the memory is read in step S501. Next, the actual road surface reaction force torque read in step S502 is compared with the friction torque of the steering mechanism by the comparator 501, and when the actual road surface reaction force torque is smaller than the friction torque of the steering mechanism (Yes), it is in the hand-off state. It is determined that If the actual road surface reaction torque is greater than or equal to the friction torque of the steering mechanism (No), the process returns to the start.

  According to the third embodiment, when the absolute value of the road reaction force torque deviation, which is the deviation between the reference road reaction torque and the actual road reaction torque, is larger than the threshold value, the release state determination unit determines the release state. Because the understeer is detected only when the driver is not in the let-off state, the erroneous determination that the understeer is detected when the driver releases the hand from the steering wheel can be eliminated. The state can be detected.

Embodiment 4 FIG.
FIG. 11 is a block diagram showing a vehicle state detection apparatus according to Embodiment 4 of the present invention. In FIG. 11, the road surface reaction force torque detecting means 601 detects the actual road surface reaction force torque received by the vehicle tire from the road surface. The reference road surface reaction torque calculating means 602 calculates a reference road surface reaction force torque that is an ideal road surface reaction force torque from the running state quantity of the vehicle. The steering state determination unit 603 determines the steering state of the driver. The road surface reaction force direction determination means 604 determines the direction of the actual road surface reaction force torque. Hand release state determination means 605 detects a state in which the driver has released his hand from the steering wheel.

  The vehicle behavior state detection means 606 is based on outputs from the road surface reaction force torque detection means 601, the reference road surface reaction force torque calculation means 602, the steering state determination means 603, the road surface reaction force direction determination means 604, and the hand-off state determination means 605. The behavior state of the vehicle is detected. A memory (not shown) for storing detection results and calculation results is provided. Of the road surface reaction force torque detection means 601, the standard road surface reaction force torque calculation means 602, the steering state determination means 603, the road surface reaction force direction determination means 604, the hand release state determination means 605, and the vehicle behavior state detection means 606, Each detection result and calculation result are stored in a memory (not shown).

  In the fourth embodiment, the steering state detection means 603 corresponding to the steering state detection means 103 in the first embodiment and the road surface reaction force direction determination corresponding to the road surface reaction force direction determination means 203 in the second embodiment. The means 605 is combined with the hand release state determination means 604 corresponding to the hand release state determination means 403 in the third embodiment.

  In the fourth embodiment, the vehicle understeer is detected when the driver's steering is in an increased state or a steered state, and the direction of the actual road surface reaction force coincides with the driver not in the state of letting it go. . Therefore, understeer is detected when the driver is turning back the steering wheel, when the driver releases the handle, and when the directions of the normal road reaction torque and the actual road reaction torque are not the same. It is possible to accurately detect the vehicle state without erroneous determination of performing.

  In the fourth embodiment, the steering state determination unit 603, the road surface reaction force direction determination unit 604, and the hand release state determination unit 605 are all combined, but at least any two of these are combined, You may make it determine the understeer of a vehicle.

1 is a block diagram showing a configuration of a vehicle state detection device according to Embodiment 1 of the present invention. 3 is a flowchart showing the operation of the vehicle state detection device according to Embodiment 1 of the present invention. It is a block diagram which shows the structure of the vehicle state detection apparatus which concerns on Embodiment 2 of this invention. It is a flowchart which shows operation | movement of the vehicle state detection apparatus which concerns on Embodiment 2 of this invention. It is a block diagram which shows the structure of the road surface reaction force direction determination means of the vehicle state detection apparatus which concerns on Embodiment 2 of this invention. It is a flowchart which shows operation | movement of the road surface reaction force direction determination means of the vehicle state detection apparatus which concerns on Embodiment 2 of this invention. It is a block diagram which shows the structure of the vehicle state detection apparatus which concerns on Embodiment 3 of this invention. It is a flowchart which shows operation | movement of the vehicle state detection apparatus which concerns on Embodiment 3 of this invention. It is a block diagram which shows the structure of the hand release state determination means of the vehicle state detection apparatus which concerns on Embodiment 3 of this invention. It is a flowchart which shows operation | movement of the hand release state determination means of the vehicle state detection apparatus which concerns on Embodiment 3 of this invention. It is a block diagram which shows the structure of the vehicle state detection apparatus which concerns on Embodiment 4 of this invention.

Explanation of symbols

101, 201, 401, 601 Road reaction force torque detection means 102, 202, 402, 602 Standard road surface reaction torque calculation means 103, 603 Steering state detection means 104, 204, 404, 606 Vehicle behavior state detection means 203, 605 Road surface Reaction force direction determination means 301 Multiplier 302, 501 Comparator 403, 604 Hand release state determination means

Claims (5)

Road surface reaction force torque detecting means for detecting an actual road surface reaction force torque received by a vehicle tire from the road surface, and a reference road surface reaction force torque for calculating a reference road surface reaction force torque in the running state based on the running state of the vehicle An understeer state of the vehicle is calculated based on a calculation means, a steering state detection means for detecting a steering state of a driver driving the vehicle, an output of the road surface reaction force torque detection means and an output of the reference road surface reaction force calculation means. Vehicle behavior state detection means for detecting, an absolute value of a deviation between an output of the reference road surface reaction torque calculation means and an output of the road surface reaction torque detection means is greater than a threshold value, and the steering state detection means is the driver when the steering state is judged to be a state where no switch back was to detect the understeer of the vehicle by the vehicle behavior state detecting means car State detecting device. Road surface reaction force torque detecting means for detecting an actual road surface reaction force torque received by a vehicle tire from the road surface, and a reference road surface reaction force torque for calculating a reference road surface reaction force torque in the running state based on the running state of the vehicle A calculating means, a road reaction force direction determining means for determining whether or not an output direction of the road surface reaction force torque detecting means and an output direction of the reference road reaction force torque calculating means are the same, and the road surface reaction Vehicle behavior state detecting means for detecting an understeer state of the vehicle based on an output of the force torque detecting means and an output of the reference road surface reaction force calculating means, and an output of the reference road surface reaction force torque calculating means and the road surface reaction force larger than the absolute value of the threshold of the output deviation of the torque detecting means, the road surface reaction force direction determination means, out of the direction of the output of the road surface reaction torque detecting means and the reference road surface reaction force torque calculation means When the direction of is determined to be consistent, the vehicle state detecting device to detect the understeer of the vehicle by the vehicle behavior state detection means.   The road surface reaction force direction determination means is based on the product of the output of the road surface reaction force torque detection means and the output of the reference road surface reaction force torque calculation means, and the direction of the output of the road surface reaction force torque detection means and the reference The vehicle state detection device according to claim 2, wherein it is determined whether or not the output directions of the road surface reaction force torque calculation means are the same. Road surface reaction force torque detecting means for detecting an actual road surface reaction force torque received by a vehicle tire from the road surface, and a reference road surface reaction force torque for calculating a reference road surface reaction force torque in the running state based on the running state of the vehicle An understeer of the vehicle based on the output of the calculation means, the release state determination means for determining the release state of the handle of the driver who drives the vehicle, the output of the road surface reaction force torque detection means and the output of the reference road surface reaction force calculation means Vehicle behavior state detection means for detecting a state, an absolute value of a deviation between an output of the reference road surface reaction force torque calculation means and an output of the road surface reaction force torque detection means is larger than a threshold value, and the release state determination means includes the when determining not let go state of the handle, the vehicle behavior state detecting means according to detect the said understeer of the vehicle has vehicle condition detection Apparatus.   5. The vehicle according to claim 4, wherein the release state determination unit determines that the release state is when the output of the road surface reaction force torque detection unit is smaller than a friction torque of a steering mechanism of the vehicle. State detection device.

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