JP6949439B2 - Vehicle condition judgment device - Google Patents

Description

The present invention relates to a vehicle state determination device for determining whether or not a vehicle is traveling.

Conventionally, a wheel speed sensor is used to calculate the vehicle speed of a vehicle such as an automobile. The wheel speed sensor includes a rotor made of a magnetic material attached to a shaft that rotates with the rotation of the wheel, and an electromagnetic pickup provided in non-contact with the rotor. A change in the magnetic field accompanying the rotation of the rotor is detected as a change in the resistance value in the electromagnetic pickup, and this change in the resistance value is output as a pulse signal, which is calculated as a vehicle speed in, for example, an ESC ECU of an automobile (see, for example, Patent Document 1). ).

Japanese Unexamined Patent Publication No. 2014-190789

In vehicle control, when the ignition switch is turned off, the engine drive is stopped and the power supply to the electrical components electrically connected to the ignition switch is also stopped.

On the other hand, the vehicle may remain in a running state even after the ignition switch is turned off and the engine drive is stopped. In such a case, it is necessary to make a part of the traveling system of the vehicle such as EPS operable, and the acquisition of the pulse signal from the wheel speed sensor and the calculation of the vehicle speed by the ESC ECU are executed.

However, the operation of the ESCECU after the ignition switch is turned off increases the power consumption and may cause the battery to run down. Therefore, in the above-mentioned exceptional operation, the ESCECU is operated only when it can be determined that the vehicle is running. It is preferable to operate it.

However, where a wheel speed sensor is used to determine whether a vehicle is running, the wheel speed sensor is subject to external vibrations, etc., even when the vehicle is stopped due to transportation or other reasons. , There is a risk that the rotor will move due to the resonance of the undercarriage of the chassis, tires, etc., and a pulse signal will be output. In this case, the ESC ECU calculates the pulse signal as the vehicle speed, resulting in power consumption.

The present invention has been made in view of the above problems, and provides a vehicle state determination device capable of reducing erroneous detection of vehicle speed by a wheel speed sensor and accurately determining a vehicle state. The purpose is.

In order to achieve the above object, an aspect of the present invention is obtained from the acceleration and angular speed of the vehicle and the wheel speed sensor when the ignition switch of the vehicle is off and a signal is obtained from the wheel speed sensor of the vehicle. It is a vehicle state determination device that determines whether or not the vehicle is running based on the signal.

As another aspect of the present invention, the vehicle state determination device on the side surface of the present invention is provided, the ignition switch of the vehicle is off, and a signal can be obtained from the wheel speed sensor of the vehicle. If it is determined that the vehicle is not running, the state determination device may be a vehicle control device that stops the operation.

The present invention as described above has the effect of reducing erroneous detection of the vehicle speed by the wheel speed sensor and making it possible to accurately determine the state of the vehicle.

A block diagram showing a configuration of a vehicle state determination device and a control device according to an embodiment of the present invention. Flow chart of operation of vehicle state determination device and control device according to the embodiment of the present invention Flow chart of operation of vehicle state determination device and control device according to the embodiment of the present invention

FIG. 1 is a block diagram showing a configuration of a vehicle state determination device of an automobile as an example and a control device having the same according to an embodiment of the present invention. As shown in FIG. 1, in the vehicle control device 1 according to the present embodiment, the ESC ECU 10 operates by receiving electric power from a power source via an ignition switch 40, and controls the vehicle in cooperation with the BODY ECU 20. Is. The ESC ECU 10 includes a microcomputer 11 including hardware such as a CPU and a memory, a YAWG sensor 12 that detects the acceleration and angular velocity of the vehicle, and a CAN driver 13 that communicates with the BODY ECU 20 and other ECUs via the CAN bus 30.

In the ESC ECU 10, the microcomputer 11 receives a pulse signal input from the wheel speed sensor 50 including the FR wheel speed sensor 50a, the FL wheel speed sensor 50b, the RR wheel speed sensor 50c, and the RL wheel speed sensor 50d, and based on this, the vehicle speed is calculated. Calculate the speed of Further, the microcomputer 11 determines the state of the vehicle by using the calculated vehicle speed and the acceleration / angular velocity information described later acquired from the YAWG sensor 12, and obtains the above determination result according to the off signal from the ignition switch 40. Based on this, it executes control to turn off (shut down) its own power supply.

The BODYECU 20 has a microcomputer and a CAN driver similar to the ESCECU 10, and communicates with the ESCECU 10 to control the operation of the electric steering lock mechanism 21 of the vehicle. The electric steering lock mechanism 21 is a means for locking the rotation of the steering of the vehicle, and operates so as to release the lock while the power is on and to lock while the power is off.

Further, the ignition switch 40 is an interface for receiving an operation input from a vehicle user, is a switch for turning on the power supply to the ESCECU 10, and is a means for outputting a control signal for turning off the power supply to the ESCECU 10. ..

In the above configuration, the ESC ECU 10 corresponds to the vehicle state determination device and the vehicle control device of the present invention.

Since the vehicle state determination device of the present embodiment has the above configuration, when a pulse signal is input from the wheel speed sensor 50, the vehicle is in a running state by acquiring a signal from the YAWG sensor 12. Determine if it is in. Further, the vehicle control device uses the determination result of the determination device of the vehicle state determination device to perform control for turning off its own power supply.

Hereinafter, an example of control by the vehicle state determination device of the present embodiment will be described with reference to the flowchart of FIG. First, when the ESCECU 10 receives the input of the pulse signal from the wheel speed sensor 50 (S10), the microcomputer 11 samples and calculates the pulse signal (S11). Further, the ESCECU 10 acquires acceleration / angular velocity information from the YAWG sensor 12 (S12). Here, the acceleration / angular velocity information includes three types of information: acceleration in the front-rear direction of the vehicle, acceleration in the lateral direction of the vehicle, and yaw rate, and is information used for detecting changes in the translation direction and the rotation direction of the vehicle. ..

Next, the ECU ECU 10 determines whether the acceleration / angular velocity information acquired from the YAWG sensor 12 has a value equal to or higher than a preset significant value (S13), and if it is greater than or equal to the significant value, the wheel in S11. The calculation result based on the pulse signal of the speed sensor 50 is set as speed information (S14), and is output to the BODY ECU 20 and other ECUs as the vehicle speed (S16).

On the other hand, when it is determined in S13 that the acceleration / angular velocity information is less than a significant value, the calculation result of S11 is reset to 0 (S15), this is set as the speed information, and the BODY ECU 20 and other ECUs are set as the vehicle speed. Output to (S16).

The generation of the pulse signal by the wheel speed sensor 50 is not only due to the drive of the wheels, but also due to the resonance of the undercarriage of the chassis, tires, etc. caused by vibration from the outside, the rotor attached to the shaft moves, and the magnetic field changes. It also occurs by doing. On the other hand, in the present embodiment, in S12 to S13, it is determined whether or not the generation of the pulse signal is due to the traveling of the vehicle by referring to the acceleration / angular velocity information of the YAWG sensor. Specifically, the presence or absence of running based on the accelerator operation in the vehicle is estimated by detecting the acceleration in the front-rear direction, and the presence or absence of running based on the steering wheel operation in the vehicle is estimated by detecting the acceleration in the lateral direction and the yaw rate.

This makes it possible to distinguish whether the pulse signal output by the wheel speed sensor is caused by the running of the vehicle or caused by other causes, reduce false detection of the vehicle speed, and accurately determine the state of the vehicle. There is.

Next, an example of the control operation by the vehicle control device using the determination result by the vehicle state determination device of the present embodiment described above will be described with reference to the flowchart of FIG. First, when the ESCECU 10 receives the input of the pulse signal from the wheel speed sensor 50, the microcomputer 11 executes S11 to S16 of the flowchart of FIG. 3 to calculate the vehicle speed (S20). Next, the ESCECU 10 determines whether or not the calculated vehicle speed is 0 (km / h) (S21), and if it is 0, it determines that the vehicle is stopped (S22). Further, if the ignition switch 40 is turned off, the ESC ECU 10 turns itself off (shut down). Along with this, the BODY ECU 20 shuts down itself after locking the steering by stopping the operation of the electric steering lock mechanism 21.

On the other hand, when the ESCECU 10 determines in S21 that the vehicle speed is not 0 (km / h), it determines that the vehicle is running (S23) and then shifts to S24, even if the ignition switch 40 is off. Since the vehicle is not stopped, it does not turn off (shut down) itself (S24), returns to S21 as the vehicle is in a running state, and repeats a series of operations.

By the above operation, it is possible to prevent the ESCECU 10 from operating based on the erroneous detection of the vehicle speed by the wheel speed sensor, and to turn off the operation of the ESCECU 10 in a state where the state of the vehicle is surely confirmed to be stopped. This makes it possible to prevent power consumption from occurring while the vehicle is stopped and to suppress battery exhaustion. Further, it is possible to prevent the function to be operated while the vehicle is stopped, such as the electric steering lock mechanism 21, from becoming inoperable.

As described above, according to the vehicle state determination device according to the embodiment of the present invention, it is possible to reduce erroneous detection of vehicle speed by the wheel speed sensor and accurately determine the state of the vehicle, and control based on this. This makes it possible to prevent problems such as power consumption while the vehicle is stopped, and to suppress battery exhaustion.

However, the present invention is not limited to the above embodiments.

In the above description, in the ESC ECU 10, the microcomputer 11 estimates whether or not the vehicle is traveling based on the steering wheel operation by detecting the acceleration in the front-rear direction, the acceleration in the lateral direction, and the yaw rate as the acceleration / angular velocity information of the YAWG sensor. Although the above description has been given, one of the detection of the lateral acceleration and the detection of the yaw rate may be selectively executed and used together with the detection of the acceleration in the front-rear direction.

Further, in the above description, the vehicle state determination device and the control device are both implemented in the ESC ECU 10, but are assumed to be implemented in the engine ECU, ABS ECU, or any other ECU mounted on the vehicle. May be good.

Further, in the above description, the present invention is assumed to be carried out in an automobile, but the vehicle of the present invention may be carried out in a two-wheeled vehicle, a train, or another vehicle.

As described above, the present invention is a vehicle state determination device, and when the ignition switch of the vehicle is off and a signal is obtained from the wheel speed sensor of the vehicle, the acceleration and angular speed of the vehicle and the wheel speed of the vehicle are obtained. It may be any one that determines whether or not the vehicle is traveling based on the signal obtained from the sensor, and is not limited by other specific purposes, uses, and configurations.

Therefore, the present invention may be carried out as if various modifications were made to the above-described embodiment, including those described above, as long as the present invention does not deviate from the gist thereof.

The present invention as described above has the effect of reducing erroneous detection of vehicle speed by the wheel speed sensor and making it possible to accurately determine the state of the vehicle, and is applied to vehicles such as engine vehicles and hybrid vehicles, for example. It is useful in.

1 Vehicle control device 10 ESCECU
11 Microcomputer 12 YAWG sensor 13 CAN driver 20 BODYECU
21 Electric steering lock mechanism 30 CAN bus 40 Ignition switch 50 Wheel speed sensor 50a FR Wheel speed sensor 50b FL Wheel speed sensor 50c RR Wheel speed sensor 50d RL Wheel speed sensor

Claims (1)

Based on the acceleration and angular velocity of the vehicle and the signal obtained from the wheel speed sensor when the ignition switch of the vehicle is off and a signal is obtained from the wheel speed sensor of the vehicle.
Determining whether the vehicle is running,
Vehicle condition determination device.

Images