JP7103302B2 - Relay device - Google Patents

Description

The present disclosure relates to an in-vehicle relay device that relays a signal between a sensor or an actuator and an ECU.

A technique for diagnosing a failure of a sensor that detects the amount of depression of the accelerator pedal of a vehicle (hereinafter referred to as an accelerator pedal sensor) is known. Patent Document 1 proposes a failure diagnosis device in a control system provided with two accelerator pedal sensors. In this device, failure diagnosis is performed based on the difference between the input signals from each accelerator pedal sensor to the ECU.

Japanese Unexamined Patent Publication No. 2003-120385

Here, it is assumed that the signal from the accelerator pedal sensor is input to the ECU via the relay device. In such a case, as described in Patent Document 1, even if the failure diagnosis is performed based on the difference in the input signals from each accelerator pedal, a failure occurs in either the accelerator pedal or the relay device. It may not be possible to determine whether or not.

One aspect of the present disclosure preferably detects anomalies in the relay device.

One aspect of the present disclosure is a relay device (1) mounted on a vehicle and relaying an input signal from a sensor to another device or an input signal from another device to an actuator. The relay device includes a setting unit (13), a generation unit (13), a relay unit (13,14), a first detection unit (S105, S115), and a second detection unit (S130, S140). .. The setting unit sets the relay state to the normal mode or the pseudo mode. The generation unit generates a pseudo output signal having an expected value according to the input signal. In the normal mode, the relay unit relays by outputting an input signal as a normal output signal, and in the pseudo mode, relays by outputting a pseudo output signal instead of the input signal. The first detection unit detects an abnormality based on the comparison result between the measured value of the input signal and the measured value of the normal output signal in the normal mode. The second detection unit detects an abnormality based on the comparison result between the expected value of the pseudo output signal and the measured value of the pseudo output signal in the pseudo mode.

According to such a configuration, the relay device compares the relayed input / output signals by a method corresponding to the normal mode or the pseudo mode. As a result, the relay abnormality can be detected correctly.
The reference numerals in parentheses described in this column and the claims indicate the correspondence with the specific means described in the embodiment described later as one embodiment, and limit the technical scope of the present disclosure. It's not something to do.

It is a block diagram of a relay device. It is a flowchart of failure diagnosis processing.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.
[1. Constitution]
The relay device 1 shown in FIG. 1 is mounted on a vehicle and is configured to relay a signal between the sensor and the ECU 3. The sensor may output a signal indicating an operation received from a user such as a driver who is in the vehicle, for example. Further, the sensor may detect peripheral information of the vehicle such as light and temperature, and output the detected information as a signal. In this embodiment, as an example, the sensor is configured as an accelerator pedal sensor 2. Then, the relay device 1 has a function of suppressing sudden start or sudden acceleration of the vehicle when a mistake in stepping on the accelerator occurs.

The accelerator pedal sensor 2 detects the amount of depression of the accelerator and outputs a signal indicating the accelerator opening corresponding to the detected amount of depression. The signal is output to the ECU 3 via the relay device 1.
The ECU 3 controls the driving force of the vehicle according to the accelerator opening degree indicated by the signal input from the accelerator pedal sensor 2 via the relay device 1. The ECU 3 sets the throttle opening degree according to, for example, the accelerator opening degree indicated by the signal.

The relay device 1 may be mounted on the vehicle at the time of manufacturing the vehicle. Further, the relay device 1 is at a stage after the vehicle equipped with the accelerator pedal sensor 2 and the ECU 3 into which the above signal from the accelerator pedal sensor 2 is directly input is manufactured (for example, the vehicle is distributed on the market). After that), it may be additionally mounted on the vehicle.

Hereinafter, the signal input from the accelerator pedal sensor 2 to the relay device 1 will be referred to as an input signal, and the signal relayed from the relay device 1 to the ECU 3 will be referred to as an output signal.
The relay device 1 includes an input terminal 11, an output terminal 12, a control circuit 13, and a switching circuit 14.

The input terminal 11 is connected to the accelerator pedal sensor 2, and an input signal from the accelerator pedal sensor 2 is input.
The output terminal 12 is connected to the ECU 3, and the output signal from the relay device 1 is output to the ECU 3 via the output terminal 12.

The switching circuit 14 has, for example, a switching element such as a relay, a transistor, or a MOS FET. By changing the state of the switching element, the path through which the input signal input from the input terminal 11 flows through the relay device 1 is changed.

The control circuit 13 includes a microcomputer having a CPU and a semiconductor memory (hereinafter, memory) including a ROM and a RAM. The CPU executes a program stored in the memory. The function of the relay device 1 is realized when the CPU executes a program stored in a memory which is a non-volatile recording medium. Moreover, when this program is executed, the method corresponding to the program is executed. The control circuit 13 may be provided with one CPU or may be provided with a plurality of CPUs. Further, the method for realizing the function of the relay device 1 is not limited to software, and some or all of the functions may be realized by using an electronic circuit. In this case, the electronic circuit may be configured as a digital circuit, an analog circuit, or a combination thereof.

The control circuit 13 sets the signal relay state to the normal mode or the pseudo mode in response to an instruction from the outside.
In the normal mode, the relay is performed by outputting the input signal as it is to the ECU 3 as a normal output signal.

On the other hand, the pseudo mode is a mode for suppressing sudden acceleration or sudden start when a mistake in stepping on the accelerator occurs. In the pseudo mode, the relay is performed by outputting the pseudo output signal generated based on the input signal to the ECU 3 instead of the normal output signal.

The control circuit 13 sets the switching circuit 14 so that when the mode shifts to the normal mode, the input signal input from the input terminal 11 is directly output from the output terminal 12 as a normal output signal via the switching circuit 14. Switch.

On the other hand, in the pseudo mode, the control circuit 13 generates a pseudo output signal having an expected value corresponding to the input signal. When shifting to the pseudo mode, the control circuit 13 replaces the input signal input from the input terminal 11 with the switching circuit 14 so that the pseudo output signal is output from the output terminal 12 via the switching circuit 14. To switch. The control circuit 13 generates a signal in which the degree of increase in the accelerator opening is suppressed as a pseudo output signal in order to suppress the acceleration of the vehicle when the accelerator opening indicated by the input signal suddenly increases.

Further, the control circuit 13 has a function of detecting an abnormality in relaying by the relay device 1. Specifically, in the normal mode, an abnormality is detected based on the comparison result between the measured value of the input signal and the measured value of the normal output signal. On the other hand, in the pseudo mode, an abnormality is detected based on the comparison result between the expected value of the pseudo output signal calculated based on the input signal and the measured value of the pseudo output signal.

[2. process]
Next, the failure diagnosis process will be described with reference to the flowchart of FIG. The failure diagnosis process may be periodically executed by the CPU of the control circuit 13.

In the failure diagnosis process, a relay abnormality is detected based on the measured value of the input signal measured at the input terminal 11 and the measured value of the normal or pseudo output signal measured at the output terminal 12. Specifically, the measured value may be, for example, a value of the signal (that is, a voltage value of the signal) at a predetermined time point. Further, the measured value may be, for example, the degree to which the value of the signal changes. That is, the difference between the values of the signals measured at predetermined measurement intervals may be used as the measured value. Further, the measured value may be, for example, an integrated value of the value of the signal in a predetermined integration period. That is, the integrated value of the value of the signal measured a plurality of times in the integration period may be used as the measured value. Hereinafter, the measured value of the input signal is set to X, and the measured values of the normal output signal and the pseudo output signal are set to Y1 and Y2, respectively.

In S100, the CPU determines whether the current mode is a normal mode or a pseudo mode. In the normal mode, the CPU shifts the process to S105, and in the pseudo mode, the CPU shifts the process to S130.

In S105, the CPU measures the input signal to obtain X, and follows the input signal during the first measurement period from the measurement timing of the input signal to the elapse of a predetermined time (hereinafter, T1), and the normal output signal. Determines if is changing.

That is, the CPU calculates a normal value, which is a value that the normal output signal should reach during the first measurement period, based on X. The normal value may be X. Further, X-x0 may be used as the determination value in consideration of the voltage drop when the relay device 1 relays the input signal. Note that x0 is a correction value corresponding to the voltage drop that occurs during relay. Further, the CPU may calculate a normal range, which is a range of values that the normal output signal should reach during the first measurement period, based on X. Specifically, the normal range may be a range of values including a normal value. As an example, the range of values in which the normal value is located in the center may be regarded as the normal range.

Then, the CPU measures the normal output signal in the first measurement period to obtain Y1, and also determines whether Y1 becomes a normal value or Y1 becomes a normal range in the first measurement period. judge. If an affirmative determination is obtained (S105: Yes), the relay is regarded as normal (S110), and this process is terminated. On the other hand, if a negative determination is obtained (S105: No), the process proceeds to S115.

In S115, the CPU determines whether or not the normal output signal changes following the input signal during the second measurement period from the end of the first measurement period to the elapse of a predetermined time (hereinafter, T2). do.

That is, the CPU measures the normal output signal in the second measurement period to obtain Y1, and in the second measurement period, Y1 becomes the above-mentioned normal value, or Y1 becomes the above-mentioned normal range. Judge whether or not. If an affirmative determination is obtained (S115: Yes), it is considered that the first abnormality has occurred (S120), and this process is terminated. On the other hand, when a negative determination is obtained (S115: No), it is considered that the second abnormality has occurred (S125), and this process is terminated.

In S130, which shifts to the pseudo mode, the CPU measures the input signal to obtain X, and calculates the expected value (hereinafter, Z) of the pseudo output signal based on X. Then, it is determined whether or not the pseudo output signal reaches Z in the third measurement period from the measurement timing of the input signal to the elapse of a predetermined time (hereinafter, T3). Further, the CPU may calculate an expected range, which is a range of values that the pseudo output signal should reach during the third measurement period, based on X. Specifically, the expected range may be a range of values including Z. As an example, the range of values in which Z is located in the center may be the expected range.

Then, the CPU measures the pseudo output signal in the third measurement period to obtain Y2, and determines whether Y2 becomes Z or Y2 falls within the expected range in the third measurement period. do. If an affirmative determination is obtained (S130: Yes), the relay is regarded as normal (S135), and this process is terminated. On the other hand, if a negative determination is obtained (S130: No), the process proceeds to S140.

In S140, the CPU determines whether or not the pseudo output signal reaches Z in the fourth measurement period from the measurement timing of the input signal to the elapse of a predetermined time (hereinafter, T4).
That is, the CPU measures the pseudo output signal in the fourth measurement period to obtain Y2, and in the fourth measurement period, does Y2 become the Z described above, or does Y2 fall within the expected range described above? Judge whether or not. If an affirmative determination is obtained (S140: Yes), it is considered that a third abnormality has occurred (S145), and this process is terminated. On the other hand, when a negative determination is obtained (S140: No), it is considered that the fourth abnormality has occurred (S150), and this process is terminated.

The CPU may store the detection result of the relay abnormality in a non-volatile storage device (for example, a flash memory) provided in the control circuit 13. Then, the CPU may output the detection result stored in the storage device to the outside via a communication line such as an in-vehicle LAN in response to an instruction from the outside. Further, the CPU may output the detection result of the relay abnormality to the outside as it is without storing it in the storage device.

Further, the first abnormality may mean that a sign of an abnormality has occurred in the relay of the signal. Further, if Y1 does not reach a normal value or a normal range within a predetermined measurement period without distinguishing between the first and second abnormalities, it may be considered that a relay abnormality has occurred.

Similarly, the third abnormality may mean that a sign of an abnormality has occurred in the relay of the signal. Further, if Y2 does not reach Z or the expected range within a predetermined measurement period without distinguishing between the third and fourth anomalies, it may be considered that a relay abnormality has occurred.

Further, the control circuit 13 may detect the voltage of the power supply of the ECU 3, the temperature and impedance of an element such as a switching element, or the admittance, temperature, humidity and the like. Then, the CPU may correct x0, the normal range, the Z, the expected range, and T1 to T4 based on these detection results.

[3. effect]
According to the embodiment described in detail above, the following effects are obtained.
(3a) The relay device 1 compares the relayed input / output signals by a method corresponding to the normal mode or the pseudo mode. As a result, the relay abnormality can be detected correctly. Further, since the relay abnormality can be correctly detected in the relay device 1, if there is an abnormality in the signal relayed by the relay device 1, whether the cause is in the relay device 1 or other than the relay device 1 such as a sensor or the like. It is easy to distinguish whether it is in the part of.

(3b) Further, the measured values of the input signals and the normal or pseudo output signals compared in S105, S115, S130, and S140 of the failure diagnosis process are the values of these signals and the degree to which these signals change. , Or the integrated value of these signals. Therefore, the abnormality of the relay can be suitably detected.

(3c) Further, the sensor is a sensor such as the accelerator pedal sensor 2 that outputs a signal indicating an operation received from a user such as a driver in a vehicle. Therefore, the abnormality of signal relay can be detected correctly.

(3d) Further, the relay device 1 additionally mounted on the vehicle can also detect the abnormality of the relay. Further, since the relay abnormality can be correctly detected in the relay device 1, if there is an abnormality in the signal relayed by the relay device 1, whether the cause is in the relay device 1 or other than the relay device 1 such as a sensor or the like. It is easy to distinguish whether it is in the part of.
[4. Other embodiments]
Although the embodiments of the present disclosure have been described above, the present disclosure is not limited to the above-described embodiments, and can be implemented in various modifications.

(4a) In the above embodiment, the configuration in which the input signal from one accelerator pedal sensor 2 is relayed to the ECU 3 is illustrated. However, the relay device 1 may relay signals from a plurality of (for example, two) accelerator pedal sensors 2 to the ECU 3. In this case, an input terminal 11, an output terminal 12, and a switching circuit 14 may be provided corresponding to each accelerator pedal sensor 2. Then, the input signal from each accelerator pedal sensor 2 may be relayed to the ECU 3 and the abnormality of the relay may be determined by the corresponding switching circuit 14 and the control circuit 13 in the same manner as in the above embodiment. ..
In the above case, the relay device 1 may relay the input signals from the plurality of accelerator pedal sensors 2 to the ECU 3 in order to carry out the fail-safe control.

(4b) In the above embodiment, the relay device 1 configured to relay the signal between the sensor and the ECU 3 is illustrated. For example, the relay device relays the signal input from the ECU to the actuator. It may be configured as follows. The actuator may operate another device such as a motor in response to the relayed signal. In this case, the relay device may set the signal relay state to two modes (that is, a normal mode and a pseudo mode) in response to an instruction from the outside, as in the above embodiment. In the normal mode, relay may be performed by outputting the input signal as it is to the actuator as a normal output signal. In the pseudo mode, as in the above embodiment, relay may be performed by outputting the pseudo output signal generated based on the signal output from the ECU to the actuator. Then, the abnormality of the relay may be determined by a method corresponding to the normal mode or the pseudo mode. In addition, this relay device intervenes in the driving force control (for example, setting of the throttle opening) of the vehicle indicated by the signal output from the ECU for actually driving the actuator, and for example, the driving force. Control can be suppressed.

(4c) A plurality of functions possessed by one component in the above embodiment may be realized by a plurality of components, or one function possessed by one component may be realized by a plurality of components. .. Further, a plurality of functions possessed by the plurality of components may be realized by one component, or one function realized by the plurality of components may be realized by one component. Further, a part of the configuration of the above embodiment may be omitted. In addition, at least a part of the configuration of the above embodiment may be added or replaced with the configuration of the other above embodiment.

(4d) In addition to the above-mentioned relay device, the present disclosure shall be realized in various forms such as a system having the relay device as a component, a program for operating a computer as the relay device, and a relay method by the relay device. You can also.

[5. Correspondence of wording]
In the present embodiment, the control circuit 13 corresponds to an example of a setting unit and a generation unit. Further, the control circuit 13 and the switching circuit 14 correspond to a part of the relay unit. Further, S105 and S115 in the failure diagnosis process correspond to the first detection unit. Further, S130 and S140 correspond to the second detection unit.

1 ... Relay device, 2 ... Accelerator pedal sensor, 3 ... ECU, 11 ... Input terminal, 12 ... Output terminal, 13 ... Control circuit, 14 ... Switching circuit

Claims (5)

A relay device (1) mounted on a vehicle that relays an input signal from a sensor to another device or an input signal from another device to an actuator.
The setting unit (13) for setting the relay state to the normal mode or the pseudo mode, and
A generation unit (13) that generates a pseudo output signal having an expected value corresponding to the input signal, and
In the normal mode, the relay unit performs the relay by outputting the input signal as a normal output signal, and in the pseudo mode, the relay unit (13) performs the relay by outputting the pseudo output signal in place of the input signal. , 14) and
In the normal mode, the first detection unit (S105, S115) that detects an abnormality based on the comparison result between the measured value of the input signal and the measured value of the normal output signal,
In the pseudo mode, the second detection unit (S130, S140) that detects an abnormality based on the comparison result between the expected value of the pseudo output signal and the measured value of the pseudo output signal,
A relay device. The relay device according to claim 1.
The measured values of the input signal, the normal output signal, and the pseudo output signal are predetermined values of the respective signals at a predetermined time point, the degree of change of the values of the respective signals, and predetermined values. A relay device that is one of the integrated values of the values of the respective signals during the period. The relay device according to claim 1 or 2.
The sensor is a relay device that outputs a signal indicating an operation received from a user as the input signal to the relay device. The relay device according to claim 3.
The sensor is a relay device, which is an accelerator pedal sensor (2) that outputs a signal indicating an operation on the accelerator pedal of the vehicle as the input signal. The relay device according to any one of claims 1 to 4.
The relay device is configured to be additionally mounted on the vehicle on which the sensor or the actuator and the other device are mounted.

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