KR20030035128A - System and method for monitoring the tire inflation pressure of an automobile using CAN - Google Patents

Abstract

The present invention uses a CAN which enables the driver to recognize the abnormality of tire inflation pressure by using the EBC2 [OC FF 19 0B] message, which stores the wheel speed, among CAN messages transmitting signals from various electronic control devices. A tire air pressure monitoring system of a vehicle and a method thereof are provided.

The monitoring method according to the present invention for achieving this is a first step of comparing the average vehicle speed (B _FRT ) of the front wheel drive shaft and the respective drive speeds (B2, B3) of both wheels, and the average vehicle speed (B _FRT ) is set deviation A second step of determining whether it is out of range, and a third step of determining whether one wheel driving speed B2 is within a deviation range if the average vehicle speed B _FRT and the respective driving speeds B2 and B3 are not equal in the first step. And a fourth step of determining whether the other wheel driving speed B3 is in the deviation range when the driving speed B2 is out of the deviation range, for each tire row.

In addition, the monitoring system according to the present invention receives a brake control device (ABS ECU) that communicates through the CAN bus, and a message containing the wheel speed per unit time among the messages transmitted through the CAN bus receives the driving state and It is characterized by consisting of a controller that calculates whether each wheel is greater than or equal to the set deviation and determines the pneumatic state, and an indicator for warning this according to the pneumatic state.

In a preferred embodiment of the invention, the controller is equipped with a processor for determining the pneumatic state, wherein the processor is configured to compare the average vehicle speed (B _FRT ) of the front wheel drive shaft and the respective driving speeds (B2, B3) of both wheels. Step 1, a second step of determining whether the average vehicle speed B _FRT is out of a set deviation range, and one wheel if the average vehicle speed B _FRT is not equal to each driving speed B2, B3 in the first step. Each tire row includes a third step of determining whether the driving speed B2 is within the deviation range, and a fourth step of determining whether the other wheel driving speed B3 is within the deviation range when the driving speed B2 is out of the deviation range. It is characterized by detecting each.

Description

System and method for monitoring the tire inflation pressure of an automobile using CAN}

The present invention relates to a system for monitoring tire inflation pressure of a vehicle using a CAN and a method thereof. More particularly, the present invention compares the actual average vehicle speed of a drive shaft stored in a CAN message with the vehicle speed of a corresponding wheel to allow a driver to recognize an abnormal tire pressure. The present invention relates to a tire inflation pressure monitoring system for a vehicle using a CAN, and a method thereof.

Recently, many electronic control devices have been applied to vehicles. Such electronic control devices communicate in one or two directions between a sensing unit such as a sensor, a controller, and an operating unit.

In recent years, many methods such as CAN (SAE J1939) have been adopted. The CAN transmits a lot of messages from various electronic control devices. Among the messages transmitted from the brake control device, EBC2 [OC FF 19 0B] stores information for monitoring each wheel speed in units of 50 ms. .

The present invention uses a CAN which enables the driver to recognize the abnormality of tire inflation pressure by using the EBC2 [OC FF 19 0B] message, which stores the wheel speed, among CAN messages transmitting signals from various electronic control devices. It is an object of the present invention to provide a vehicle tire pressure monitoring system and method thereof.

1 is a block diagram showing a tire pressure monitoring system according to the present invention,

2 is a flow chart for explaining a tire air pressure monitoring method according to the present invention,

[Description of Symbols for Main Parts of Drawing]

10: brake control unit (ABS ECU) 20: controller

21: CAN bus 30: indicator

The monitoring method according to the present invention for achieving this is a first step of comparing the average vehicle speed (B _FRT ) of the front wheel drive shaft and the respective drive speeds (B2, B3) of both wheels, and the average vehicle speed (B _FRT ) is set deviation A second step of determining whether it is out of range, and a third step of determining whether one wheel driving speed B2 is within a deviation range if the average vehicle speed B _FRT and the respective driving speeds B2 and B3 are not equal in the first step. And a fourth step of determining whether the other wheel driving speed B3 is in the deviation range when the driving speed B2 is out of the deviation range, for each tire row.

In addition, the monitoring system according to the present invention receives a brake control device (ABS ECU) that communicates through the CAN bus, and a message containing the wheel speed per unit time among the messages transmitted through the CAN bus receives the driving state and It is characterized by consisting of a controller that calculates whether each wheel is greater than or equal to the set deviation and determines the pneumatic state, and an indicator for warning this according to the pneumatic state.

In a preferred embodiment of the invention, the controller is equipped with a processor for determining the pneumatic state, wherein the processor is configured to compare the average vehicle speed (B _FRT ) of the front wheel drive shaft and the respective driving speeds (B2, B3) of both wheels. Step 1, a second step of determining whether the average vehicle speed B _FRT is out of a set deviation range, and one wheel if the average vehicle speed B _FRT is not equal to each driving speed B2, B3 in the first step. Each tire row includes a third step of determining whether the driving speed B2 is within the deviation range, and a fourth step of determining whether the other wheel driving speed B3 is within the deviation range when the driving speed B2 is out of the deviation range. It is characterized by detecting each.

Hereinafter, with reference to the accompanying drawings, the configuration and effect of the present invention will be described.

1 is a block diagram showing a tire pressure monitoring system according to the present invention.

The present invention uses a CAN communication method for transmitting a signal generated from each tire to a brake control device (ABS ECU), the tire pressure monitoring system according to the present invention is a brake control device for obtaining a signal for the air pressure from each tire ( ABS ECU) 10, a controller 20 that receives a message through a CAN bus 21 for inputting and outputting signals to and from the device 10, and an indicator 30 for displaying an air pressure state according to signal control of the controller. Consists of

Here, the brake control device (ABS ECU) 10 is used in the conventional technology that controls the driving speed and braking force of the wheel to control the braking force of the bra, the CAN bus 21 is such a brake A typical transmission scheme used for inputting and outputting control signals to the control apparatus 10 and other components such as an ECU, such as an ECU, which requires vehicle speed and braking force, is shown.

In addition, the controller 20 calculates the rotational speed per unit time of each wheel from a message containing a signal for a vehicle speed among various messages transmitted through the CAN bus 21, for example, EBC2 [OC FF 19 0B]. The air pressure state of the tire is detected and displayed on the indicator 30 by analyzing it. To this end, the controller 20 is equipped with a processor for detecting the tire pressure by comparing and analyzing these messages.

The processor detects tire inflation pressure according to a tire inflation pressure monitoring method of a vehicle using a CAN according to the present invention, which is described with reference to FIG. Describe with monitoring method.

In the tire air pressure monitoring method according to the present invention, as a first step, the average vehicle speed B _FRT for one row of front wheels is compared with driving speeds B2 and B3 of both wheels. Here, the average vehicle speed B _FRT is a value obtained by dividing the wheel speed input from the tire for one row of front wheels by two, and the driving speeds B2 and B3 are values obtained by detecting the actual driving speed of both front wheels. . If the average vehicle speed B _FRT obtained as described above is equal to each of the driving speeds B2 and B3 of both driving wheels, the processor determines that the tire pressure is normal. However, if not equal to the above, if the average vehicle speed B _FRT is within each of the driving speeds B2 and B3 of both drive wheels within the set deviation C3 range, a second detecting whether the difference value is within a preset deviation range The steps will be carried out.

In the second step, first, it is determined whether the average vehicle speed B _FRT is within a first set deviation C1. At this time, if the average vehicle speed B _FRT is within the first set deviation C1 range, the processor determines that the tire pressure is in a normal state (display 3), and returns to the first stage again, and compares the vehicle speed again in each step. If the average vehicle speed B _FRT is out of the first set deviation C1 range, it is determined whether the average vehicle speed B _FRT is higher than the second set deviation C2.

Here, the set deviations C1 and C2 are obtained by calculating a difference value between the average speeds of the rear row 1st row and the second row, that is, the average vehicle speed B _{FRT of the} front row 1 row and the average vehicle speeds of the rear row 1st row and the second row, respectively. It is a difference value obtained by subtracting the average vehicle speed of the first and second columns from the average vehicle speed B _FRT , and in a preferred embodiment of the present invention, the first set deviation C1 is 1 to 5 Km / h and the second set deviation C2. ) Is preferably set to 5 Km / h or more.

In the second step, if the average vehicle speed B _FRT is out of the second set deviation C2 range, the tire inflation pressure is abnormal (display 1), that is, the driving speed of the rear wheels is higher than the driving speed of the front wheels. It is determined that it is running too slowly, and it is judged to be an abnormal state. Further, if the average vehicle speed B _FRT is within the second set deviation C2 range, the average vehicle speed B _FRT is outside the first set deviation C1 (out of the average vehicle speed range in the rear row 1). Since it does not deviate from the second set deviation C2 (without the average vehicle speed range of the second row of the rear wheels), it is determined that the vehicle needs to be inspected because it can travel but can reach a dangerous state (display 2). .

On the other hand, if the driving wheels B2 and B3 different from the average vehicle speed B _FRT differ from the front wheel tire set deviation, that is, the third set deviation C3 in the first step, is the air pressure of the rear tire out of the deviation range? Will be judged. That is, in the first step, the average vehicle speed B _FRT is equal to each of the driving speeds B2 and B3 of the front wheel tire, and the absolute value obtained by subtracting each driving speed B2 and B3 from the average vehicle speed B _FRT is set. It means that it is within the deviation C3.

Here, the third set deviation C3 and the fourth set deviation C4 to be described later obtain the average speed values of the first row and the second row of the rear wheels, respectively, and the average vehicle speed B _{FRT of the} first row of the front wheels, respectively. In a preferred embodiment of the present invention, the first set deviation C1 is 1 to 5 Km / h and the second set deviation C2 is set to 5 Km / h or more.

As described above, when the value obtained by subtracting the average values B2 and B3 of each rear wheel axle from the average vehicle speed B _FRT is outside the range of the third set deviation C3, the third step is performed.

In the third step, whether the drive speed B2 of the first row of rear wheels is in the third set deviation C3 range, that is, the sum of the drive speed B2 and the third set deviation C3 is the average vehicle speed B. _FRT ). If the sum of the driving speed B2 and the set deviation C3 is greater than the average vehicle speed B _FRT , the sum of the drive speed B2 and the fourth set deviation C4 is equal to the average vehicle speed B _FRT . Will be compared. At this time, when the driving speed B2 and the fourth set deviation C4 are larger than the average vehicle speed B _FRT , the tires in the rear row first row become more than the set deviation compared to the average vehicle speed of the front wheel tire, so that driving is difficult. (display 5). In addition, if the sum of the driving speed B2 and the fourth set deviation C4 is smaller than the average vehicle speed B _FRT , the rear wheel first row tires may be driven, but the tire inflation pressure may be slightly different. You are judged to be in the state you need (display 4). In the fourth step, the result of detecting the state of the rear wheel second row tire is compared with the average vehicle speed B _FRT .

Finally, if the sum of the driving speed B2 and the third set deviation C3 is less than the average vehicle speed B _FRT , the fourth step is performed. In the fourth step, the driving speed B3 of the rear wheel second row tire is compared with the sum of the fourth set deviation C4. If the sum of the fourth set deviation C4 is greater than the average vehicle speed B _FRT , the rear wheel first row tire is also higher than the average vehicle speed B _FRT . You see it as a display (display 6). Further, if the sum of the driving speed B3 and the fourth set deviation C4 is smaller than the average vehicle speed B _FRT , the rear wheel first row tire is higher than the average vehicle speed B _FRT , but the driving speed B3 of the second row tire is ) Is within the set range, it is possible to drive, but it is judged as a state requiring display (display 7). In the fourth step, the result of detecting the state of the rear second row tire is compared with the average vehicle speed BFRT.

The indicator 30 displays the current state of each tire row in response to a signal from the controller 20 so that the driver can check. Such an indicator 30 is a digital method and shows how many rows of tires are out of the set deviation range so that it is necessary to check or cause a danger in driving, or use LEDs to reduce tire inflation by reducing the speed of the tires. It will show a lack or condition to be checked.

As described above, the present invention is configured to detect and display the air pressure state of the tire through the difference in the vehicle speed from the vehicle speed information generated in the conventional brake control device, thereby obtaining the following effects.

1) Since the tire pressure can be detected through the CAN communication port, which is a standard communication protocol, any vehicle can be applied to a vehicle employing the CAN communication method.

2) Tire pressure monitoring can be performed at a lower cost than conventional air pressure monitoring devices.

3) The display shows the air pressure of the tire through the display, allowing the driver to visually recognize the tire condition.

Claims (3)

A first step of comparing the average vehicle speed B _FRT of the front wheel drive shaft and the respective drive speeds B2 and B3 of both wheels, A second step of determining whether the average vehicle speed B _FRT is out of a set deviation range; A third step of determining whether one wheel driving speed B2 is within a deviation range when the average vehicle speed B _FRT and the driving speeds B2 and B3 are not equal in the first step; And detecting a fourth step of determining whether the other wheel driving speed B3 is within the deviation range for each tire row when the driving speed B2 is out of the deviation range. A brake control unit (ABS ECU) that communicates via a CAN bus, A controller for determining a pneumatic state by receiving a message containing a wheel speed per unit time from among the messages transmitted through the CAN bus, calculating a driving state of the vehicle and whether each wheel is equal to or greater than a set deviation; A tire inflation pressure monitoring system for a vehicle using a car, characterized in that the indicator is configured to warn it according to the inflation pressure. The processor of claim 2, wherein the controller is equipped with a processor for determining an air pressure state. A first step of comparing the average vehicle speed B _FRT of the front wheel drive shaft and the respective drive speeds B2 and B3 of both wheels, A second step of determining whether the average vehicle speed B _FRT is out of a set deviation range; A third step of determining whether one wheel driving speed B2 is within a deviation range when the average vehicle speed B _FRT and the driving speeds B2 and B3 are not equal in the first step; And a fourth step of determining whether the other wheel driving speed B3 is within the deviation range for each tire row if the driving speed B2 is out of the deviation range.