KR20230006666A - Brake system and controlling method thereof - Google Patents

Abstract

The present invention relates to a brake system and a control method thereof. According to one embodiment of the present invention, the brake system, which has an advantage of being simple and economical, includes: a first control unit which can control a brake operation in a normal state; a second control unit which performs a redundancy role for the first control unit when the first control unit is in an abnormal state; and a switching unit which switches a plurality of wheel speed sensors detecting a speed for each wheel to be connected to the first control unit or the second control unit. The switching unit connects a part of the plurality of wheel speed sensors to the first control unit and connects the remaining to the second control unit during an operation to check whether the first control unit is normal.

Description

Brake system and its control method {BRAKE SYSTEM AND CONTROLLING METHOD THEREOF}

The present invention relates to a brake system and a control method thereof, and more particularly, to a brake system including a main control unit and an auxiliary control unit performing a redundancy role for the main control unit and a control method thereof.

Recently, as interest in autonomous vehicles or electric vehicles increases, a brake system having stronger braking force and stability is required. To this end, an integrated electronic brake system (IDB) is built by using an electronic master booster instead of a conventional hydraulic system and integrating an anti-lock brake system (ABS) and an electric stability control (ESC) system. : Integrated Dynamic Brake) was developed.

By using this IDB system, it is possible to reduce the size and weight of the brake system, and while providing various functions, stability is also greatly improved. However, since the conventional IDB system consists of a large portion of electronic equipment, there is a risk of failure.

If a breakdown occurs while the vehicle is driving and the brake system is in a non-operating state, it may lead to a serious accident, and thus it is necessary to prepare for the inoperable state of the brake system. Accordingly, a brake system (hereinafter, referred to as a “redundancy brake system”) including a main control unit and an auxiliary control unit performing a redundancy role for the main control unit is provided.

In this redundancy brake system, the main control unit and the auxiliary control unit can determine whether each other is in a normal state through CAN communication. However, when a situation in which CAN communication is impossible, such as a disconnection of a CAN communication line, occurs, there is a problem in that it is impossible to grasp such a normal state between the main control unit and the auxiliary control unit.

KR10- 2020-0140754 A

In order to solve the problems of the prior art as described above, an object of the present invention is to provide a technology capable of determining a normal state between a main control unit and an auxiliary control unit even in a situation where CAN communication is not possible.

However, the problem to be solved by the present invention is not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the description below. There will be.

A brake system according to an embodiment of the present invention for solving the above problems includes a first control unit having control initiative of a brake operation in a normal state; a second control unit performing a redundancy role for the first control unit when the first control unit is in an abnormal state; and a switching unit configured to connect a plurality of wheel speed sensors that sense speeds of each wheel to the first control unit or the second control unit.

The switching unit may connect some of the plurality of wheel speed sensors to the first controller and connect the rest to the second controller during an operation for checking whether the first controller is normal.

When there is no decrease in vehicle speed corresponding to the driver's brake pedal operation during the operation for the confirmation, control initiative of the brake operation may be handed over to the second controller.

The first control unit may determine whether or not the vehicle speed corresponding to the brake pedal operation is reduced through the partial wheel speed sensors, and the second control unit may determine whether or not the vehicle speed corresponding to the brake pedal operation is reduced by using the remaining wheel speed sensors. It can be identified through the wheel speed sensor of .

If there is a decrease in vehicle speed corresponding to the driver's brake pedal operation during the operation for the confirmation, the first control unit may maintain control initiative of the brake operation, and the switching unit may set the remaining wheel speed sensors to the first It can be connected to the control unit.

For a vehicle in smart cruise driving or autonomous driving, when there is no decrease in vehicle speed for a predetermined time during the operation for checking, the control initiative of the brake operation may be transferred from the first control unit to the second control unit. .

When there is a decrease in vehicle speed within a predetermined time during the operation for confirmation, the first control unit may maintain control initiative of the brake operation, and the switching unit may connect the remaining wheel speed sensors to the first control unit. can

The switching unit includes a plurality of first switches for switching connections between the plurality of wheel speed sensors and the first control unit, and a plurality of second switches for switching connections between the plurality of wheel speed sensors and the second control unit, respectively. can do.

During the checking operation, among the first and second switches connected to the part of the wheel speed sensors, the first switch may be turned on and the second switch may be turned off, and the remaining wheel speed sensors may be turned on. Among the first and second switches connected to the sensor, the first switch may be turned off and the second switch may be turned on.

An operation of the first switch may be controlled by a first controller, and an operation of the second switch may be controlled by a second controller.

The operation for confirmation may be an operation in a situation in which communication between the first and second controllers is disconnected.

A control method of a brake system according to an embodiment of the present invention includes the steps of having a control initiative of a brake operation by a first control unit; Checking whether the first control unit is normal; And as a result of the normality check, when the first control unit is in a normal state, the first control unit maintains control initiative of the brake operation, and when the first control unit is in an abnormal state, redundancy for the first control unit ( and transferring control initiative of the brake operation to the second control unit performing a redundancy role.

The checking may include connecting some of the plurality of wheel speed sensors for detecting the speed of each wheel to the first control unit and connecting the rest to the second control unit.

The checking may include determining whether the first control unit is in a normal state or an abnormal state according to whether a vehicle speed corresponding to a driver's brake pedal operation is reduced.

The checking may include determining, by the first controller, whether or not the vehicle speed corresponding to the brake pedal operation is reduced through the some wheel speed sensors, and the second controller, which determines whether or not the vehicle speed corresponding to the brake pedal operation is reduced. It may include determining whether or not is reduced through the remaining wheel speed sensors.

The checking may include determining that the first control unit is in a normal state or an abnormal state according to whether or not the vehicle speed decreases within a preset time for the vehicle in smart cruise driving or autonomous driving.

The brake system includes a plurality of first switches for switching connections between the plurality of wheel speed sensors and the first control unit, and a plurality of second switches for switching connections between the plurality of wheel speed sensors and the second control unit, respectively. The switching step may include turning on a first switch and turning off a second switch among first and second switches connected to some of the wheel speed sensors, and turning on the other wheel speed sensors. Among the connected first and second switches, the first switch may be turned off and the second switch may be turned on.

The present invention configured as described above has an advantage of being able to determine a normal state between the main control unit and the auxiliary control unit even in a situation where CAN communication is impossible.

In addition, since the present invention does not require a separate hardware connection line between the main control unit and the auxiliary control unit, there is an advantage in that it is simple and cost-effective.

The effects obtainable in the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below. will be.

1 shows a schematic configuration diagram of a brake system 100 according to an embodiment of the present invention.
2 is a diagram of wheel speed sensors (WSS) 81, 82, 83, when the first control unit 30 has the initiative to control the brake operation in the brake system 100 according to an embodiment of the present invention. 84) and a connection configuration diagram between the first and second control units 30 and 50.
3 shows wheel speed sensors 81, 82, 83, 84 and first and second controllers 81, 82, 83, and 84 when the second control unit 50 takes control of the brake operation in the brake system 100 according to an embodiment of the present invention. 2 shows a configuration diagram of the connection between the control units 30 and 50.
FIG. 4 shows an example of an operation for checking whether the first controller 30 is normal in FIG. 2 .
5 shows a flow chart of a control method according to an embodiment of the present invention.

The above objects and means of the present invention and the effects thereof will become clearer through the following detailed description in conjunction with the accompanying drawings, and accordingly, those skilled in the art to which the present invention belongs can easily understand the technical idea of the present invention. will be able to carry out. In addition, in describing the present invention, if it is determined that a detailed description of a known technology related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted.

Terms used in this specification are for describing the embodiments and are not intended to limit the present invention. In this specification, singular forms also include plural forms in some cases unless otherwise specified in the text. In this specification, terms such as "comprise", "have", "provide" or "have" do not exclude the presence or addition of one or more other elements other than the mentioned elements.

In this specification, terms such as “or” and “at least one” may represent one of the words listed together, or a combination of two or more. For example, "or B" and "at least one of B" may include only one of A or B, or may include both A and B.

In this specification, descriptions following "for example" may not exactly match the information presented, such as cited characteristics, variables, or values, and tolerances, measurement errors, limits of measurement accuracy and other commonly known factors It should not be limited to the embodiments of the present invention according to various embodiments of the present invention with effects such as modifications including.

In this specification, when a component is described as being 'connected' or 'connected' to another component, it may be directly connected or connected to the other component, but there may be other components in the middle. It should be understood that it may be On the other hand, when a component is referred to as 'directly connected' or 'directly connected' to another component, it should be understood that no other component exists in the middle.

In the present specification, when an element is described as being 'on' or 'in contact with' another element, it may be in direct contact with or connected to the other element, but another element may be present in the middle. It should be understood that On the other hand, if an element is described as being 'directly on' or 'directly in contact with' another element, it may be understood that another element in the middle does not exist. Other expressions describing the relationship between components, such as 'between' and 'directly between', can be interpreted similarly.

In this specification, terms such as 'first' and 'second' may be used to describe various elements, but the elements should not be limited by the above terms. In addition, the above terms should not be interpreted as limiting the order of each component, and may be used for the purpose of distinguishing one component from another. For example, a 'first element' may be named a 'second element', and similarly, a 'second element' may also be named a 'first element'.

Unless otherwise defined, all terms used in this specification may be used in a meaning commonly understood by those of ordinary skill in the art to which the present invention belongs. In addition, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless explicitly specifically defined.

Hereinafter, a preferred embodiment according to the present invention will be described in detail with reference to the accompanying drawings.

1 shows a schematic configuration diagram of a brake system 100 according to an embodiment of the present invention.

The brake system 100 according to an embodiment of the present invention controls the braking force of a vehicle as a redundancy brake system. Referring to FIG. 1 , a brake system 100 according to an embodiment of the present invention is connected to a brake pedal 10 that is pressurized or released by a driver to instruct braking of a vehicle, and the brake pedal 10 It may include a pedal sensor 20 that detects a brake pedal operation 10 and a first controller 30 that controls a brake operation of the vehicle according to a signal detected by the pedal sensor 20 (ie, a sensor value). there is.

Of course, when the vehicle is in automatic driving such as smart cruise driving or autonomous driving, the first controller 30 may control the brake operation of the vehicle according to the automatic driving situation regardless of the sensor value of the pedal sensor 20. That is, when a signal for a situation in which braking force needs to be provided is transmitted from various other sensors or an electronic control unit (ECU) (not shown) during automatic driving of the vehicle, the first control unit 30 responds to the corresponding transmission signal. brake operation can be controlled.

In addition, the brake system 100 includes a second control unit 50 that is an auxiliary control unit that performs a redundancy role with respect to the first control unit 30 that functions as a main control unit of the redundancy brake system. That is, in the brake system 100, when the first control unit 30 is in a normal state, the first control unit 30 maintains the control initiative for the brake operation of the vehicle, and when the first control unit 30 is in an abnormal state. In this case, the control initiative for the brake operation of the vehicle is transferred from the first control unit 30 to the second control unit 50.

The first and second controllers 30 and 50 may be implemented as ECUs. For example, the first and second controllers 30 and 50 may include a micro controller unit (MCU) that provides a control function and various drivers (valve drivers, motor drivers, etc.) controlled by the MCU. , but is not limited thereto.

On the other hand, when the first controller 30 has the control initiative for the brake operation, the first controller 30 mechanically operates to provide the sensor value of the pedal sensor 20 or the braking force of the vehicle in an automatic driving situation. By controlling the hydraulic device 40, the brake operation of the vehicle can be controlled. In this case, the flow of hydraulic pressure delivered to the wheel cylinders provided in the respective wheels 71, 72, 73, and 74 of the vehicle may be controlled by the main hydraulic device 40.

Of course, when the second control unit 50 takes control of the brake operation, the second control unit 50 may control the brake operation of the vehicle by controlling the auxiliary hydraulic pressure device 60 . In this case, the auxiliary hydraulic device 60 may control the flow of hydraulic pressure transmitted to the wheel cylinder.

However, the present invention is not limited thereto, and the first and second controllers 30 and 50 control the operation of various types of mechanical devices other than the main hydraulic device 40 and the auxiliary hydraulic device 60, thereby controlling the vehicle's Brake operation can be controlled.

FIG. 2 shows wheel speed sensors (WSS) (81, 82, 83, 84) and a connection configuration diagram between the first and second control units 30 and 50. 3 shows the wheel speed sensors 81, 82, 83, and 84 and the first control unit 50 in the brake system 100 according to an embodiment of the present invention when the second control unit 50 takes control of the brake operation. And a connection configuration diagram between the second control units 30 and 50 is shown. Also, FIG. 4 shows an example of an operation for checking whether the first controller 30 is normal in FIG. 2 .

2 to 4, the brake system 100 includes a plurality of wheel speed sensors 81, 82, 83, and 84 for detecting the speed of each wheel as a first control unit 30 or a second control unit 30. Switching units 91 and 92 performing a switching operation to be connected to the control unit 50 may be included. That is, the first switching unit 91 includes a plurality of first switches S1, S2, S3, and S4 for switching connections between the plurality of wheel speed sensors 81, 82, 83, and 84 and the first control unit 30. can include In addition, the second switching unit 92 includes a plurality of second switches S5, S6, S7, and S8 for switching connections between the plurality of wheel speed sensors 81, 82, 83, and 84 and the second controller 50. can include

The first switching unit 91 is provided as a separate configuration for the first control unit 30 as shown in FIGS. 2 to 4, or unlike the first control unit 30 as shown in FIGS. 2 to 4 It can be provided with a configuration within. Similarly, the second switching unit 92 may be provided as a separate component for the second controller 50 or as a component within the second controller 50 .

When the first and second switching units 91 and 92 are provided as components within the first and second control units 30 and 50, the plurality of first switches S1, S2, S3, and S4 have a plurality of wheel speeds. Connections between the sensors 81, 82, 83, and 84 and the MCU in the first control unit 30 may be switched, and the plurality of second switches S5, S6, S7, and S8 may include a plurality of wheel speed sensors 81, 82, 83, 84) and the MCU in the second controller 50 may be switched.

Switching of the first switching unit 91 on/off may be controlled by the first control unit 30 or an MCU within the first control unit 30 . That is, the first control unit 30 or the MCU in the first control unit 30 transfers a switching control signal to each of the first switches S1, S2, S3, and S4 of the first switching unit 91 to each first switch. On/off of (S1, S2, S3, S4) can be controlled. Hereinafter, the switching between each of the first switches S1, S2, S3, and S4 and the first control unit 30 by the first switching unit 91 is performed with each of the first switches S1, S2, S3, and S4. 1 It may mean switching between MCUs in the control unit 30.

Similarly, the on/off switching of the second switching unit 92 may be controlled by the second control unit 50 or an MCU within the second control unit 50 . That is, the second control unit 50 or the MCU in the second control unit 50 transmits a switching control signal to each second switch S5, S6, S7, and S8 of the second switching unit 92 to each second switch. On/off of (S5, S6, S7, S8) can be controlled. Hereinafter, the switching between each second switch (S5, S6, S7, S8) and the second control unit 50 by the second switching unit 92 is performed with each second switch (S5, S6, S7, S8). 2 It may mean switching between MCUs in the control unit 50.

However, the first and second switching units 91 and 92 operate such that each wheel speed sensor 81, 82, 83, and 84 is connected to only one of the first and second control units 30 and 50. That is, the first and second switching units 91 and 92 operate so that the respective wheel speed sensors 81, 82, 83 and 84 are not simultaneously connected to the first and second control units 30 and 50.

For example, the first wheel speed sensor 81 may be connected to only one of the first and second controllers 30 and 50, and not be connected to the first and second controllers 30 and 50 at the same time. This connection method is equally applied to the other wheel speed sensors 82, 83, and 84. However, in the present invention, although the number of wheels 71, 72, 73, and 74 and wheel speed sensors 81, 82, 83, and 84 has been illustrated and described as four, the present invention is not limited thereto, and the number is not limited thereto. It may be more or less.

Meanwhile, the first and second controllers 30 and 50 may exchange information about each other's states through CAN communication using CAN communication lines CAN1 and CAN2. However, when a situation in which CAN communication is disconnected (off), such as disconnection of the CAN communication lines CAN1 and CAN2, occurs, it may be impossible for the first and second control units 30 and 50 to grasp each other's states. In order to solve this problem, the brake system 100 according to the present invention performs an operation for checking whether the first controller 30 having the control initiative of the current brake operation is normal (hereinafter, referred to as “check operation”). can be done At this time, the first and second controllers 30 and 50 may control the confirmation operation.

First, referring to FIG. 4 , during a predetermined time (hereinafter, referred to as “confirmation time”) of a confirmation operation, the first and second switching units 91 and 92 operate a plurality of wheel speed sensors 81, 82, A switching operation is performed to connect some of the plurality of wheel speed sensors 83 and 84 to the first controller 30, and a switching operation to connect the rest of the plurality of wheel speed sensors 81, 82, 83 and 84 to the second controller 50. do. Of course, control of the first and second switching units 91 and 92 may be performed by the first and second control units 30 and 50 as described above.

For example, during the confirmation time, some first switches S1 and S2 are turned on and some second switches (S1 and S2) are turned on so that the first and second wheel speed sensors 81 and 82 are connected to the first control unit 30. S5 and S6) may be turned off. In addition, the remaining first switches S3 and S4 are turned off so that the third and fourth wheel speed sensors 83 and 84 are connected to the second controller 50, and the remaining second switches S7 and S8 are turned off. can be turned on. However, the present invention is not limited thereto. That is, the first and second switching units 91 and 92 may perform a switching operation in a manner different from that described above, and accordingly, each wheel speed sensor 81, 82, 83, and 84 is also controlled in a manner different from that described above. It may be connected to the first and second control units 30 and 50.

Through such a switching operation of the first and second switching units 91 and 92, the first and second control units 30 and 50 use the wheel speed sensors connected to the first and second controllers 91 and 92 to generate braking force at the time when braking force is required during the checking operation. You can check if it works properly (i.e. if the sensor value sensed by the connected wheel speed sensor is reduced) or not.

At this time, the timing at which braking force is required during the checking operation is when the driver operates the brake pedal 10 during the checking time (hereinafter referred to as “first case”), or the vehicle in autonomous driving operates at the vehicle speed for a preset time during the checking time. It may be a case where there is no decrease in (hereinafter referred to as “second case”). That is, in the first case, the driver intervenes for the brake operation, and in the second case, the brake operation is automatically controlled without the driver's intervention.

Hereinafter, the control method of the brake system 100 including the above-described confirmation operation will be described in more detail.

5 shows a flow chart of a control method according to an embodiment of the present invention.

The control method according to an embodiment of the present invention is performed in the brake system 100, and its execution can be controlled by the first and second controllers 30 and 50. That is, referring to FIG. 5 , the control method according to an embodiment of the present invention may include S101 to S103.

S101 is a step in which the first controller 30 takes control of the brake operation. That is, as an initial stage of vehicle operation, the brake operation may be controlled by the first controller 30 , which is the main controller of the brake system 100 .

Thereafter, S102 is a step of performing the above-described confirmation operation. That is, when a situation in which communication is disconnected between the first and second control units 30 and 50 occurs, the first and second control units 30 and 50 determine whether or not the brake operation control of the first control unit 30 is normal. This is the verification step.

At this time, during the confirmation time, among the plurality of wheel speed sensors 81, 82, 83, 84, some 81 and 82 are connected to the first controller 30, and the others 83 and 84 are connected to the second controller 50. ) can be connected to For example, some first switches S1 and S2 are turned on and some second switches S5 and S6 are turned on so that the first and second wheel speed sensors 81 and 82 are connected to the first controller 30. can be turned off. In addition, the remaining first switches S3 and S4 are turned off so that the third and fourth wheel speed sensors 83 and 84 are connected to the second controller 50, and the remaining second switches S7 and S8 are turned off. can be turned on.

Thereafter, whether or not the brake operation control of the first controller 30 is in a normal state may be checked in various ways according to the first case or the second case.

First, in the first case, the first and second controllers 30 and 50 set the first controller 30 to a normal state or an abnormal state according to whether the vehicle speed corresponding to the driver's operation of the brake pedal 10 is reduced. can be judged by That is, if there is no decrease in vehicle speed corresponding to the driver's operation of the brake pedal 10 during the check time, the control of the brake operation by the first control unit 30 corresponds to an abnormal state. At this time, the first and second controllers 30 and 50 may determine whether the brake pedal 10 is operated through sensor values of the pedal sensors 20 connected thereto. In addition, the first control unit 30 may determine whether the vehicle speed corresponding to the operation of the brake pedal 10 is reduced through sensor values of some of the wheel speed sensors 81 and 82 connected thereto. Similarly, the second control unit 50 may determine whether or not the vehicle speed corresponding to the operation of the brake pedal 10 decreases through the remaining wheel speed sensors 83 and 84 connected thereto.

Meanwhile, in the second case, the first and second control units 30 and 50 determine whether the first control unit 30 is in a normal state or an abnormal state according to whether or not the vehicle speed of the autonomously driving vehicle decreases within a preset time. can do. That is, when there is no decrease in vehicle speed during a predetermined time period during the confirmation time, the brake operation control of the first control unit 30 may correspond to an abnormal state. This is because a deceleration operation is necessarily performed within a certain time in the case of a vehicle that is normally traveling automatically. In this case, the first control unit 30 may determine whether or not the vehicle speed decreases during a preset time through sensor values of some of the wheel speed sensors 81 and 82 connected thereto. In addition, the second control unit 50 may determine whether or not the vehicle speed decreases during a predetermined time period through sensor values of the remaining wheel speed sensors 83 and 84 connected thereto.

If, in the first or second case, the braking force works properly, the first and second controllers 30 and 50 may determine (confirm) that the first controller 30 is in a normal state.

Specifically, in the first case, in a state in which the sensor value of the pedal sensor 20 indicating that the brake pedal 10 is operating is received, in the wheel speed sensor connected to the first and second controllers 30 and 50, respectively. When the sensed sensor value decreases by the reference value, it is determined that the first controller 30 is in a normal state. At this time, the first control unit 30 may determine that the first control unit 30 is in a normal state if no other DTCs occur other than DTCs (Diagnostic Trouble Codes) related to disconnection (off) with the CAN bus (BUS). In addition, in the second case, when the sensor value detected by the wheel speed sensor connected to the first and second controllers 30 and 50 is reduced by a reference value within a preset time, the first controller 30 is in a normal state. it is judged to be

On the other hand, in the first case, if the braking force does not work properly, the first and second controllers 30 and 50 may determine (confirm) that the first controller 30 is in an abnormal state.

That is, in the first case, in a state in which the sensor value of the pedal sensor 20 indicating that the brake pedal 10 is operated is received, the wheel speed sensor connected to the first and second controllers 30 and 50 respectively detects If the detected sensor value does not decrease by the reference value, it is determined that the first controller 30 is in an abnormal state. At this time, other DTCs related to non-deceleration of vehicle speed may occur in addition to DTCs related to disconnection (off) with the CAN bus (BUS). Further, in the second case, if the sensor values detected by the wheel speed sensors connected to the first and second controllers 30 and 50 do not decrease by the reference value within a preset time, the first controller 30 is in an abnormal state. it is judged to be

Thereafter, S103 is a step in which the vehicle determines the control initiative of the brake operation according to the normality check result of the first control unit 30 confirmed in S102.

That is, when the first control unit 30 is in a normal state as a result of S102, the first control unit 30 maintains control of the brake operation. At this time, after a time corresponding to the confirmation time, the first and second switching units 91 and 92 disconnect the remaining wheel speed sensors 83 and 84 from the second control unit 50, and the remaining wheel speeds The sensors 83 and 84 can be switched to be connected to the first controller 30 again. That is, the connection shown in FIG. 2 may be reconfigured by turning on the remaining first switches S3 and S4 and turning off the remaining second switches S7 and S8. As a result, the first controller 30 can stably control the brake operation using all the wheel speed sensors 81, 82, 83, and 84 connected thereto.

On the other hand, when the first control unit 30 is in an abnormal state as a result of S102, the control initiative of the brake operation is transferred from the first control unit 30 to the second control unit 50. At this time, after a time corresponding to the confirmation time, the second control unit 30 disconnects some of the wheel speed sensors 81 and 82 from the first control unit 30, and the part of the wheel speed sensors 81 and 82 Can be switched to be connected to the second control unit 50. That is, the connection shown in FIG. 3 can be configured by turning on some of the first switches S1 and S2 and turning off some of the second switches S5 and S6. As a result, the second control unit 50 can stably control the brake operation using all the wheel speed sensors 81, 82, 83, and 84 connected thereto.

Of course, in S103, control of the first and second switching units 91 and 92 may be performed by the first and second control units 30 and 50.

The present invention configured as described above has an advantage of being able to determine a normal state between the main control unit and the auxiliary control unit even in a situation where CAN communication is impossible. Accordingly, the present invention can solve the problem of the conventional redundancy brake system in which the state of each other cannot be recognized between the main control unit and the auxiliary control unit in a situation where CAN communication is impossible. In addition, since the present invention does not require a separate hardware connection line between the main control unit and the auxiliary control unit, there is an advantage in that it is simple and cost-effective.

In the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention is not limited to the described embodiments, and should be defined by the following claims and equivalents thereof.

10: brake pedal 20: pedal sensor
30: first control unit 40: main hydraulic device
50: second control unit 60: auxiliary hydraulic device
71, 72, 73, 74: wheel 81, 82, 83, 84: wheel speed sensor

Claims (15)

a first control unit having control initiative of a brake operation in a normal state;
a second control unit performing a redundancy role for the first control unit when the first control unit is in an abnormal state; and
A switching unit configured to connect a plurality of wheel speed sensors for detecting speeds of each wheel to the first control unit or the second control unit;
The switching unit connects some of the plurality of wheel speed sensors to the first controller and connects the rest to the second controller during an operation to check whether the first controller is normal.
According to claim 1,
When there is no decrease in vehicle speed corresponding to the driver's brake pedal operation during the operation for the confirmation, the control initiative of the brake operation is handed over to the second control unit.
According to claim 2,
The first control unit determines whether the vehicle speed corresponding to the brake pedal operation is reduced through the some wheel speed sensors,
The second control unit determines whether the vehicle speed corresponding to the brake pedal operation is reduced through the remaining wheel speed sensors.
According to claim 2,
If there is a decrease in vehicle speed corresponding to the driver's brake pedal operation during the operation for the confirmation, the first control unit maintains control initiative of the brake operation, and the switching unit transmits the remaining wheel speed sensors to the first control unit. to the brake system.
According to claim 1,
A brake system in which control of the brake operation is passed from the first control unit to the second control unit when there is no decrease in vehicle speed for a predetermined time during the operation for checking, for a vehicle in smart cruise driving or autonomous driving. .
According to claim 5,
When there is a decrease in vehicle speed within a predetermined time during the operation for confirmation, the first control unit maintains control initiative of the brake operation, and the switching unit connects the remaining wheel speed sensors to the first control unit. system.
According to claim 1,
The switching unit includes a plurality of first switches for switching connections between the plurality of wheel speed sensors and the first control unit, and a plurality of second switches for switching connections between the plurality of wheel speed sensors and the second control unit, respectively. brake system to do.
According to claim 7,
During the operation for the confirmation, among the first and second switches connected to the part of the wheel speed sensors, the first switch is turned on and the second switch is turned off, and the first switch is connected to the other wheel speed sensors. Among the first and second switches, the first switch is turned off and the second switch is turned on.
According to claim 7 or 8,
The brake system of claim 1 , wherein an operation of the first switch is controlled by a first control unit and an operation of the second switch is controlled by a second control unit.
According to claim 1,
The operation for confirmation is an operation in a situation in which communication between the first and second controllers is disconnected.
As a control method of the brake system,
a step in which a first control unit takes control of a brake operation;
Checking whether the first control unit is normal; and
As a result of checking the normality, when the first control unit is in a normal state, the first control unit maintains the control initiative of the brake operation, and when the first control unit is in an abnormal state, redundancy for the first control unit ) handing over the control initiative of the brake operation to the second controller performing the role;
The checking step includes connecting some of the plurality of wheel speed sensors to the first control unit and connecting the rest to the second control unit among a plurality of wheel speed sensors for detecting the speed of each wheel.
According to claim 11,
The checking step includes determining that the first control unit is in a normal state or an abnormal state according to whether a vehicle speed corresponding to a driver's brake pedal operation is reduced.
According to claim 12,
The checking may include determining, by the first controller, whether or not the vehicle speed corresponding to the brake pedal operation is reduced through the some wheel speed sensors, and the second controller, which determines whether or not the vehicle speed corresponding to the brake pedal operation is reduced. A control method comprising the step of determining whether or not is reduced through the remaining wheel speed sensors.
According to claim 11,
The checking step includes determining that the first control unit is in a normal state or an abnormal state according to whether or not the vehicle speed decreases within a preset time for the vehicle in smart cruise driving or autonomous driving.
According to claim 11,
The brake system includes a plurality of first switches for switching connections between the plurality of wheel speed sensors and the first control unit, and a plurality of second switches for switching connections between the plurality of wheel speed sensors and the second control unit, respectively. contains,
The switching step may include turning on a first switch among first and second switches connected to some of the wheel speed sensors and turning off a second switch, and turning on the first and second switches connected to the remaining wheel speed sensors. A control method comprising the step of turning off the first switch and turning on the second switch among the two switches.

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