Brake switch state determination method and system

Abstract

This invention relates to the field of vehicle braking technology, specifically to a method and system for determining the state of a brake switch. The method includes the following steps: determining whether the brake switch signal is reliable; when the brake switch signal is unreliable, determining whether a fault indication signal indicating a brake switch malfunction has been received; when a fault indication signal is received, receiving a first signal and determining whether the first signal is less than a first threshold; when the first signal is less than the first threshold, determining that the brake switch is not activated; when the first signal is greater than or equal to the first threshold, determining that the brake switch is activated. By adding the determination of whether the brake switch is faulty and the first signal when the brake switch signal is unreliable, this method avoids situations where, for example, the brake switch is activated but the brake switch signal is unreliable, resulting in the brake lights failing to illuminate when the brake pedal is pressed, or the brake lights failing to illuminate when the preceding vehicle brakes, preventing following vehicles from promptly judging the driving behavior of the preceding vehicle and potentially leading to traffic accidents.

Description

Technical Field

[0001] This invention relates to the field of vehicle braking technology, and specifically to a method and system for determining the state of a brake switch. Background Technology

[0002] Vehicles are primarily used for transporting people and / or goods, and their use has expanded rapidly with economic development. When driving a vehicle, the driver brakes as needed. By pressing the brake pedal, the brake switch sends a signal to the vehicle's control system, illuminating the brake lights. If the brake switch malfunctions, the control system cannot receive the signal and therefore cannot illuminate the brake lights. If the vehicle in front brakes and the following vehicle cannot determine the driver's actions by observing the brake lights, a traffic accident is highly likely. Summary of the Invention

[0003] Therefore, the present invention provides a method for determining the status of a brake switch, which solves or partially solves the problem in the prior art where a malfunction in the vehicle brake switch causes the brake lights to fail to illuminate, which can easily lead to traffic accidents.

[0004] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0005] A method for determining the state of a brake switch includes the following steps:

[0006] Determine whether the brake switch signal is reliable;

[0007] When the brake switch signal is unreliable, determine whether a fault indication signal indicating a brake switch malfunction has been received.

[0008] Upon receiving a fault indication signal, the system receives the first signal and determines whether the first signal is less than the first threshold.

[0009] When the first signal is less than the first threshold, it is determined that the brake switch is not activated;

[0010] When the first signal is greater than or equal to the first threshold, the brake switch is determined to be activated.

[0011] Optionally, after determining whether the brake switch signal is reliable, the process further includes the following steps:

[0012] When the brake switch signal is reliable, the brake switch is determined to be activated.

[0013] Optionally, after determining whether a fault indication signal indicating a brake switch malfunction has been received when the brake switch signal is unreliable, the step further includes the following steps:

[0014] If no fault indication signal is received, it is determined that the brake switch is not in operation.

[0015] Optionally, determining whether the brake switch is faulty includes the following steps:

[0016] Determine whether the brake switch signal is reliable;

[0017] When the brake switch signal is unreliable, determine whether the second signal is greater than the second threshold.

[0018] When the second signal is greater than the second threshold, it is determined that the brake switch is faulty, and a fault indication signal is transmitted.

[0019] When the second signal is less than or equal to the second threshold, the brake switch is determined to be fault-free, and no fault indication signal indicating a fault is transmitted.

[0020] Optionally, after determining whether the brake switch signal is reliable, the process further includes the following steps:

[0021] When the brake switch signal is reliable, the brake switch is determined to be fault-free, and no fault indication signal is transmitted.

[0022] Optionally, after determining that the brake switch is faulty and transmitting a fault indication signal when the second signal is greater than the second threshold, the step further includes the following steps:

[0023] Transmit a fault indication signal indicating a malfunction to the warning device.

[0024] Optionally, the method for determining the state of the brake switch includes,

[0025] The first component is used to receive a fault indication signal and a first signal indicating that the brake switch is faulty, and to determine the status of the brake switch.

[0026] The second component is used to determine whether the brake switch is faulty and to transmit a fault indication signal and a first signal indicating that a fault exists.

[0027] Optionally, the first component is a body controller, and the second component is a stability control system;

[0028] When the stability control system determines that the brake switch is faulty, the valves and motors in the stability control system do not operate.

[0029] Optionally, both the first signal and the second signal are the main cylinder pressure values.

[0030] In the brake switch state determination method of the present invention, the reliability of the brake switch signal is determined. If the brake switch signal is unreliable, it is further determined whether a fault indication signal indicating a brake switch malfunction has been received. If a fault indication signal is received, the brake switch is considered faulty. At this point, a first signal is received, and it is determined whether the first signal is less than a first threshold to determine the state of the brake switch. That is, when the brake switch signal is unreliable, by adding the determination of whether the brake switch is faulty and the first signal, the determination of the brake switch state is enhanced. This avoids situations where, for example, the brake switch is activated but the brake switch signal is unreliable, resulting in the brake pedal being pressed but the brake lights not illuminating, or the following vehicle braking but the brake lights not illuminating, preventing the following vehicle from promptly judging the driving behavior of the preceding vehicle and leading to a traffic accident. Therefore, the brake switch state determination method of this application has the advantage of greater safety.

[0031] Another objective of this invention is to provide a brake switch status judgment system to solve or partially solve the problem that a malfunction in the brake switch of an existing vehicle can cause the brake lights to fail to illuminate, which can easily lead to traffic accidents.

[0032] To achieve the above objectives, the technical solution of the present invention is implemented as follows:

[0033] A brake switch status determination system, comprising,

[0034] Brake lights are used to indicate braking status and prevent rear-end collisions.

[0035] Brake switch, used to output brake switch signal;

[0036] A stability control system, connected to the brake switch, is used to determine whether the brake switch is faulty;

[0037] The body controller, connected to the brake lights, the brake switch, and the stability control system, is used to determine the state of the brake switch based on the fault indication signal and the first signal transmitted by the stability control system, and to control the brake lights to illuminate based on the state of the brake switch.

[0038] The brake switch state determination system and the brake switch state determination method described above have the same advantages over the prior art, and will not be repeated here.

[0039] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0040] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of the first step of the brake switch state determination method according to the present invention;

[0042] Figure 2 This is a schematic diagram of the second process of the brake switch state determination method described in this invention;

[0043] Figure 3 This is a connection diagram of the brake switch state determination system described in this invention;

[0044] Explanation of reference numerals in the attached figures:

[0045] 1-Brake light; 2-Brake switch; 3-Stability control system; 4-Body controller; 5-Brake pedal. Detailed Implementation

[0046] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0047] In the description of this invention, it should be noted that the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0048] The brake switch state determination method of this application embodiment can be executed by the vehicle controller, which includes brake light 1, brake switch 2, stability control system 3, body controller 4, etc.

[0049] like Figure 1 As shown, one embodiment of this application discloses a method for determining the state of a brake switch, including the following steps:

[0050] S11, determine whether the brake switch signal is reliable;

[0051] S12, when the brake switch signal is unreliable, determine whether a fault indication signal indicating that brake switch 2 is faulty has been received;

[0052] S13, when a fault indication signal is received, the first signal is received and it is determined whether the first signal is less than the first threshold.

[0053] S14, when the first signal is less than the first threshold, it is determined that the brake switch 2 is not activated;

[0054] S15, when the first signal is greater than or equal to the first threshold, it is determined that the brake switch 2 is activated.

[0055] The vehicle has a brake pedal 5, which is used to limit power and slow down the vehicle to a stop. A brake switch 2 is mounted on the brake pedal 5 and controls the brake lights 1. When the brake pedal 5 is pressed, the brake switch 2 is activated, and the brake lights 1 illuminate. Illuminating the brake lights 1 serves to warn following vehicles of the braking behavior of vehicles in front and behind, preventing rear-end collisions and other accidents.

[0056] When brake switch 2 is activated, it emits a brake switch signal. The reliability of this signal can be determined by, for example, by collecting the output voltage of brake switch 2 and using a high voltage reading to assess its reliability. For instance, if the voltage threshold is 6V, when the driver presses the brake pedal 5, if the output voltage of brake switch 2 collected by the body controller 4 is greater than 6V, the brake switch signal is determined to be reliable (set to 1), and the body controller 4 controls the brake lights 1 to illuminate. If the output voltage of brake switch 2 collected by the body controller 4 is less than or equal to 6V, the brake switch signal is determined to be unreliable (set to 0).

[0057] Both the first and second thresholds are set according to usage requirements.

[0058] If the brake switch 2 is not activated, the brake light 1 will not illuminate; if the brake switch 2 is activated, the brake light 1 will illuminate.

[0059] In the brake switch state determination method of this application embodiment, it is determined whether the brake switch signal of brake switch 2 is reliable. When the brake switch signal is unreliable, it is further determined whether a fault indication signal indicating a fault in brake switch 2 has been received. When a fault indication signal is received, brake switch 2 is faulty. At this time, a first signal is received, and it is determined whether the first signal is less than a first threshold to determine the state of brake switch 2. That is, when the brake switch signal is unreliable, by adding the determination of whether brake switch 2 is faulty and the first signal, the determination of the state of brake switch 2 is enhanced. This avoids situations where, for example, brake switch 2 is activated but the brake switch signal is unreliable, the brake pedal 5 is pressed but the brake light 1 cannot be lit, and the following vehicle cannot timely judge the driving behavior of the preceding vehicle, leading to a traffic accident. Therefore, the brake switch state determination method in this application embodiment has the advantage of being safer.

[0060] like Figure 1As shown, in one embodiment, after determining whether the brake switch signal is reliable, the step further includes step S16, whereby if the brake switch signal is reliable, the brake switch 2 is determined to be activated.

[0061] When the brake switch signal is reliable, brake switch 2 is activated, and brake light 1 illuminates. Illuminating brake light 1 alerts following vehicles to the braking action of the vehicle in front, effectively preventing traffic accidents.

[0062] like Figure 1 As shown, in one embodiment, after determining whether a fault indication signal indicating a fault in brake switch 2 is received when the brake switch signal is unreliable, the method further includes step S14, in which if no fault indication signal is received, it is determined that brake switch 2 is not operating.

[0063] If no fault indication signal is received, it is determined that brake switch 2 is not functioning. By adding a check for faults in brake switch 2, the status of brake switch 2 can be accurately determined.

[0064] like Figure 1 As shown, in one embodiment, determining whether the brake switch 2 is faulty includes the following steps:

[0065] S21, determine whether the brake switch signal is reliable;

[0066] S22, when the brake switch signal is unreliable, determine whether the second signal is greater than the second threshold;

[0067] S23, when the second signal is greater than the second threshold, it is determined that the brake switch 2 is faulty, and a fault indication signal is transmitted.

[0068] S24, when the second signal is less than or equal to the second threshold, it is determined that the brake switch 2 is fault-free and no fault indication signal is transmitted.

[0069] When the brake switch signal is unreliable, the system further determines whether brake switch 2 is faulty by checking if the second signal exceeds a second threshold. In other words, when the brake switch signal is unreliable, the system adds a check on the second signal to accurately determine if brake switch 2 is faulty. This determination of brake switch 2's fault status prevents situations where, for example, brake switch 2 operates but the brake switch signal is unreliable, leading to a decision that brake switch 2 is not operating and brake lights 1 fail to illuminate, thus avoiding traffic accidents.

[0070] like Figure 1 As shown, in one embodiment, after determining whether the brake switch signal is reliable, the method further includes step S24, where if the brake switch signal is reliable, the brake switch 2 is determined to be fault-free and no fault indication signal is transmitted.

[0071] like Figure 1 As shown, in one embodiment, after determining that the brake switch 2 is faulty when the second signal is greater than the second threshold and transmitting a fault indication signal, the method further includes step S25, transmitting the fault indication signal to the warning device.

[0072] The warning device is used to alert the driver that the brake switch 2 has malfunctioned, so that the malfunction of the brake switch 2 can be resolved in a timely manner.

[0073] In one embodiment, the warning device is the vehicle's instrument panel. The driver obtains information about a malfunction in the brake switch 2 through the display on the instrument panel, and can repair or replace the brake switch 2 in a timely manner to avoid accidents caused by a malfunction in the brake switch 2.

[0074] like Figure 1 As shown, in one embodiment, it includes two structures: a first component and a second component. The first component is used to receive a fault indication signal and a first signal indicating that the brake switch 2 is faulty, and to determine the state of the brake switch 2. The second component is used to determine whether the brake switch 2 is faulty, and to transmit the fault indication signal and the first signal indicating that the brake switch 2 is faulty.

[0075] The first component is used to execute steps S11 to S16, and the second component is used to execute steps S21 to S25. The first and second components execute different steps to facilitate the implementation of the brake switch state determination method.

[0076] In one embodiment, the first component is the body controller 4, and the second component is the stability control system 3; when the stability control system 3 determines whether the brake switch 2 is faulty, the valve and motor in the stability control system 3 do not operate.

[0077] In automotive engineering, the Body Controller 4 (BCM) refers to the electronic control unit used to control the electrical systems of the vehicle body. The Body Controller 4 can be connected to other on-board electronic control units (ECUs) via a bus.

[0078] Stability Control System 3 is the vehicle's active safety system, a further extension of the Anti-lock Braking System (ABS) and Traction Control System (TCS). It adds yaw rate sensors, lateral acceleration sensors, and steering wheel angle sensors to ensure lateral stability during vehicle cornering. The ECU controls the driving and braking forces of the front and rear, and left and right wheels. Stability Control System 3 includes valves and motors, and its inactivity prevents them from affecting the determination of whether brake switch 2 is malfunctioning.

[0079] like Figure 2 In another embodiment, both the first signal and the second signal are the main cylinder pressure values.

[0080] In another embodiment, determining whether the brake switch 2 is faulty includes the following steps:

[0081] S31, determine whether the brake switch signal is reliable;

[0082] S32, when the brake switch signal is unreliable, determine whether the second signal is greater than the second threshold;

[0083] S33, when the second signal is greater than the second threshold, it is determined that the brake switch 2 is faulty, and a fault indication signal is transmitted.

[0084] S34, when the second signal is less than or equal to the second threshold, it is determined that the brake switch 2 is fault-free, and a fault indication signal indicating that there is no fault is transmitted;

[0085] S35, when the brake switch signal is reliable, determine that brake switch 2 is fault-free and transmit a fault indication signal indicating that there is no fault;

[0086] S36, transmits a fault indication signal indicating a fault to the warning device.

[0087] At this point, the steps for determining brake switch 2 are as follows:

[0088] S41, determine whether the brake switch signal is reliable;

[0089] S42, when the brake switch signal is unreliable, determine whether a fault indication signal is received indicating that brake switch 2 is faulty;

[0090] S43, when a fault indication signal indicating a fault is received, a first signal is received and it is determined whether the first signal is less than a first threshold.

[0091] S44, when the first signal is less than the first threshold, it is determined that the brake switch 2 is not activated;

[0092] S45, when the first signal is greater than or equal to the first threshold, it is determined that the brake switch 2 is activated;

[0093] S46, when the brake switch signal is reliable, it is determined that brake switch 2 is activated;

[0094] S47, when a fault indication signal indicating that there is no fault is received, it is determined that brake switch 2 is not activated.

[0095] In the brake switch status determination method of this application embodiment, the stability control system 3 and the body controller 4 respectively add determination strategies for whether the brake switch 2 is faulty and the behavior of the brake switch 2, so as to avoid the problem that the brake switch 2 cannot remind the following vehicle that the front vehicle is braking due to a fault, which is very likely to cause traffic accidents.

[0096] An embodiment of this application also discloses a brake switch status determination system, including a brake light 1, a brake switch 2, a stability control system 3, a body controller 4, and a brake pedal 5. The brake light 1 is used to warn of the braking status to prevent rear-end collisions; the brake switch 2 is used to output a brake switch signal; the stability control system 3 is connected to the brake switch 2 and is used to determine whether the brake switch 2 is faulty; the body controller 4 is connected to the brake light 1, the brake switch 2, and the stability control system 3, and is used to determine the status of the brake switch 2 based on the fault indication signal and the first signal transmitted by the stability control system 3, and control the brake light 1 to illuminate based on the status of the brake switch 2.

[0097] Specifically, in a typical vehicle, brake lights 1 include the high-mounted brake light and the side brake lights, etc.

[0098] In practical applications, the working strategy of the brake switch status determination system is as follows:

[0099] The body controller 4 collects the output voltage of the brake switch 2 via a hardwired connection and determines the reliability of the brake switch signal based on the validity of the high voltage. For example, if the voltage threshold is set to 6V, when the driver presses the brake pedal 5, if the output voltage of the brake switch 2 collected by the body controller 4 is greater than 6V, the brake switch signal is determined to be valid and reliable (set to 1), and the body controller 4 controls the brake light 1 to illuminate; if the output voltage of the brake switch 2 collected by the body controller 4 is less than or equal to 6V, the brake switch signal is determined to be unreliable (set to 0); if the brake switch signal is determined to be unreliable, the next step of judgment is then performed.

[0100] The master cylinder pressure signal of the stability control system 3 is adjusted to remain valid even when a fault is detected in brake switch 2. When there is no valve or motor operation, the brake switch signal is 0. When the master cylinder pressure exceeds the second threshold, a fault is detected in brake switch 2. At this time, the stability control system 3 transmits a fault indication signal for brake switch 2 and continues to send the actual value of the master cylinder pressure, which serves as the first signal, to the CAN network.

[0101] The body controller 4 determines whether the driver has pressed the brake pedal 5 by receiving and reading the master cylinder pressure from the CAN network. When the body controller 4 determines that the brake switch signal is set to 0, if no fault indication signal is received, the fault indication signal is 0, and it is determined that the driver has not braked, so the brake light 1 is not illuminated; if a fault indication signal indicating a fault in the brake switch 2 is received, the fault indication signal is 1, and the master cylinder pressure is checked. If the master cylinder pressure is less than the second threshold, it is determined that the driver has not pressed the brake, so the brake light 1 is not illuminated; if the master cylinder pressure is greater than or equal to the second threshold, it is determined that the driver has pressed the brake, so the brake light 1 is illuminated.

[0102] By adding judgment strategies regarding whether brake switch 2 is faulty and the behavior of brake switch 2 to the stability control system 3 and the body controller 4 respectively, the problem of failing to alert following vehicles and preceding vehicles when brake switch 2 is faulty is avoided. The brake switch status judgment system has the advantage of being safer.

[0103] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.

Claims

1. A method for determining the state of a brake switch, characterized in that, Includes the following steps, Determine whether the brake switch signal is reliable; When the brake switch signal is unreliable, determine whether a fault indication signal indicating that the brake switch (2) is faulty has been received; Upon receiving a fault indication signal, the system receives a first signal and determines whether the first signal is less than a first threshold; the first signal is the main cylinder pressure value. When the first signal is less than the first threshold, it is determined that the brake switch (2) is not activated; When the first signal is greater than or equal to the first threshold, the brake switch (2) is determined to be activated; The stability control system and the body controller are respectively equipped with strategies to determine whether the brake switch is faulty and the behavior of the brake switch. When the stability control system determines that the brake switch is faulty, the valves and motors in the stability control system do not operate. The determination of whether the brake switch signal is reliable includes: The output voltage of the brake switch is acquired by hard-wired data acquisition from the vehicle body controller and compared with a preset voltage threshold. If the output voltage is greater than the preset voltage threshold, the brake switch signal is considered reliable; if the output voltage is less than or equal to the preset voltage threshold, the brake switch signal is considered unreliable.

2. The method for determining the state of a brake switch according to claim 1, characterized in that, After determining whether the brake switch signal is reliable, the following steps are also included: When the brake switch signal is reliable, the brake switch (2) is determined to be activated.

3. The method for determining the state of a brake switch according to claim 1, characterized in that, When the brake switch signal is unreliable, after determining whether a fault indication signal indicating a fault in brake switch (2) has been received, the following steps are also included: When no fault indication signal is received, it is determined that the brake switch (2) is not activated.

4. The method for determining the state of a brake switch according to claim 1, characterized in that, Determining whether the brake switch (2) is faulty includes the following steps: Determine whether the brake switch signal is reliable; When the brake switch signal is unreliable, determine whether the second signal is greater than the second threshold; the second signal is the main cylinder pressure value. When the second signal is greater than the second threshold, it is determined that the brake switch (2) is faulty, and a fault indication signal is transmitted. When the second signal is less than or equal to the second threshold, the brake switch (2) is determined to be fault-free and no fault indication signal is transmitted.

5. The method for determining the state of a brake switch according to claim 4, characterized in that, After determining whether the brake switch signal is reliable, the following steps are also included: When the brake switch signal is reliable, the brake switch (2) is determined to be fault-free and no fault indication signal is transmitted.

6. The method for determining the state of a brake switch according to claim 4, characterized in that, After determining that the brake switch (2) is faulty when the second signal is greater than the second threshold and transmitting a fault indication signal, the procedure further includes the following steps: Transmit a fault indication signal indicating a malfunction to the warning device.

7. The method for determining the state of a brake switch according to claim 4, characterized in that, include, The first component is used to receive a fault indication signal and a first signal indicating that the brake switch (2) is faulty, and to determine the state of the brake switch (2); The second component is used to determine whether the brake switch (2) is faulty and to transmit a fault indication signal and a first signal indicating that a fault exists.

8. The method for determining the state of a brake switch according to claim 7, characterized in that, The first component is the body controller (4), and the second component is the stability control system (3).

9. A brake switch state determination system, applied to the brake switch state determination method as described in any one of claims 1-8, characterized in that, include, Brake light (1) is used to warn of braking status to prevent rear-end collisions; Brake switch (2), used to output brake switch signal; The stability control system (3) is connected to the brake switch (2) and is used to determine whether the brake switch (2) is faulty; The body controller (4) is connected to the brake light (1), the brake switch (2) and the stability control system (3), and is used to determine the state of the brake switch (2) according to the fault warning signal and the first signal transmitted by the stability control system (3), and control the brake light (1) to be lit according to the state of the brake switch (2).

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