Sensor cleaning system and fault diagnosis method thereof

Abstract

The present invention relates to a sensor cleaning system and a fault diagnosis method thereof, the sensor cleaning system comprising: an air tank connected to a compressor through a first connector and configured to be filled with high-pressure air by the compressor; a roof module; a rear bumper module; an air flow path connected to the air tank and branched into a first branch air flow path and a second branch air flow path by a second connector, in which the first branch air flow path is connected to the roof module by a third connector and the second branch air flow path is connected to the rear bumper module by a fourth connector; a pressure sensor mounted on each of the air tank, the roof module, and the rear bumper module and configured to measure a pressure of each of the air tank, the roof module, and the rear bumper module; and a controller configured to determine a connection state of the first connector, the second connector, the third connector, and the fourth connector through a pressure difference between the air tank, the roof module, and the rear bumper module.

Description

Technical Field

[0001] The present invention relates to a sensor cleaning system and a fault diagnosis method thereof, and more particularly to a sensor cleaning system and a fault diagnosis method thereof which utilize pressure difference for fault diagnosis. Background Art

[0002] Typically, autonomous vehicles or vehicles equipped with driving assistance equipment use GPS location information and signals obtained from multiple sensors based on road map information to automatically control driving to the destination or assist the driver in driving, thereby achieving safe driving.

[0003] Therefore, in order to safely perform autonomous driving or assist the driver in driving the vehicle, it is very important to correctly identify objects around the vehicle, so the performance of the sensor needs to be ensured.

[0004] Typically, when foreign matter obstructs the sensor, the sensor's performance degrades. This degradation poses a safety risk to autonomous driving, so driving control is usually transferred to the driver or sensor cleaning is performed.

[0005] Such sensor cleaning methods include using a physical wiper, utilizing water or cleaning fluid pressure (washer cleaning), utilizing air pressure (air cleaning), and the like. Summary of the invention

[0006] The present invention aims to provide a sensor cleaning system and a fault diagnosis method thereof, which can correctly diagnose the position or orientation of a fault such as leakage. This is achieved by checking the connection state of each of the air tank, the rear bumper module and the roof module with the connector using the pressure difference detected from the installed pressure sensor when the compressor is driven. In addition, this is achieved by diagnosing whether there is a leak when each pressure sensor is installed on the air tank, the rear bumper module and the roof module and the high-pressure air supplied from the air tank is distributed to the rear bumper module or the roof module to perform cleaning.

[0007] A sensor cleaning system according to an embodiment of the present invention includes: an air tank connected to a compressor through a first connector and configured to be filled with high-pressure air by the compressor; a roof module; a rear bumper module; an air flow path connected to the air tank and branched into a first branch air flow path and a second branch air flow path through a second connector. The first branch air flow path is connected to the roof module through a third connector, and the second branch air flow path is connected to the rear bumper module through a fourth connector. The system also includes a pressure sensor mounted on each of the air tank, the roof module, and the rear bumper module and configured to measure the pressure of each; and a controller configured to determine the connection status of the first connector, the second connector, the third connector, and the fourth connector by the pressure difference between the air tank, the roof module, and the rear bumper module.

[0008] When it is determined that the pressure does not continuously increase while the compressor is driven, the controller determines whether leakage occurs depending on the connection status of the first connector to the fourth connector using the pressure differences between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module.

[0009] When it is determined that each of the pressure differences between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module is less than a set reference pressure difference, the controller determines that a leak has occurred in the first connector.

[0010] In addition, when it is determined that: i) the first connector is normal; ii) the pressure difference between the air tank and the rear bumper module and the pressure difference between the air tank and the roof module exceed the set reference pressure difference; and iii) the absolute value of the pressure difference between the rear bumper module and the roof module is less than the set reference pressure difference, the controller determines that a leak has occurred in the second connector.

[0011] In addition, when it is determined that the first connector and the second connector are normal and the pressure detected from the roof module is less than the pressure detected from the rear bumper module, the controller determines that a leak has occurred in the third connector. In addition, when it is determined that the pressure detected from the roof module is greater than the pressure detected from the rear bumper module, the controller determines that a leak has occurred in the fourth connector.

[0012] The sensor cleaning system according to the first embodiment of the present invention further includes an outside air temperature sensor configured to measure an outside air temperature of the vehicle and detect a change in the outside air temperature.

[0013] The controller determines that a fine leak has occurred when it is determined that a change in the outside air temperature transmitted from the outside air temperature sensor is within a set range and when the compressor is driven more than a set number of times within a set time when a distributor configured to enable air to be distributed from the roof module and the rear bumper module is blocked.

[0014] Furthermore, when determining that no pressure drop is detected from the pressure sensor after distributing air to the roof module and the rear bumper module, the controller determines that the first and second branch air flow paths respectively connected to the roof module and the rear bumper module are in a blocked state.

[0015] The controller determines all pressure changes of the rear bumper module and the roof module, and individually diagnoses the blockage status of all air flow paths connected to the roof module and the rear bumper module.

[0016] When it is determined that the measured pressure change between the rear bumper module and the roof module is less than a set critical value, the controller determines that the first branch air flow path and the second branch air flow path are in a blocked state. In addition, after a set pause time, the controller can control the pressure sensor to measure the pressure of the rear bumper module and the roof module to determine the pressure change.

[0017] According to another embodiment of the present invention, a method for diagnosing a fault of a sensor cleaning system includes: a first operation step: determining by a controller whether the compressor is driven. The method also includes a second operation step: when it is determined that the pressure does not continuously increase when the compressor is driven, the controller determines the leakage of a first connector, a second connector, a third connector, or a fourth connector installed in an air flow path connecting the air tank, the dash cross member, the roof module, and the rear bumper module through the pressure difference between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module.

[0018] The second operation step includes determining that a leak has occurred in the first connector when it is determined that each pressure difference between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module is less than a set reference pressure difference.

[0019] In addition, the second operating step includes: when it is determined that: i) the first connector is normal; ii) the pressure difference between the air tank and the rear bumper module, and the pressure difference between the air tank and the roof module exceed the set reference pressure difference; and iii) the absolute value of the pressure difference between the rear bumper module and the roof module is less than the set reference pressure difference, it is determined that a leak has occurred in the second connector.

[0020] In addition, the second operation step includes: when it is determined that the first connector and the second connector are normal, and the pressure detected from the roof module is less than the pressure detected from the rear bumper module, determining that a leak has occurred in the third connector. The second operation step also includes: when it is determined that the pressure detected from the roof module is greater than the pressure detected from the rear bumper module, determining that a leak has occurred in the fourth connector.

[0021] In addition, the second operation step includes determining that a fine leak has occurred when it is determined that: i) a change in the outside air temperature transmitted from the outside air temperature sensor is within a set range, and ii) the compressor is driven more than a set number of times within a set time when a distributor configured to enable air to be distributed from the roof module and the rear bumper module is blocked.

[0022] According to another embodiment of the present invention, a method for diagnosing a fault in a sensor cleaning system includes: a first operation step: in a stopped state of a vehicle, when it is determined that no pressure drop is detected from a plurality of pressure sensors after air is distributed to a rear bumper module and a roof module, a controller diagnoses that the air flow path is blocked. The method also includes a second operation step: in a rear bumper module or a roof module that is initially diagnosed as blocked, the pressure is measured by distributing air to a first sensor connected to a corresponding first channel among a plurality of channels. The second operation step also includes: in the rear bumper module or the roof module, the controller compares the measured pressure by distributing air to a second sensor connected to a corresponding second channel among a plurality of channels. The method also includes a third operation step: when it is determined that the pressure change between the first sensor and the second sensor in the rear bumper module or the roof module is less than a set critical value, the controller finally diagnoses the blocked state of the second channel.

[0023] The third operation step includes determining all pressure changes in a plurality of channels connected to a plurality of sensors in the rear bumper module or the roof module, and individually diagnosing blockage states of all channels connected to the plurality of sensors in the rear bumper module or the roof module.

[0024] The second operation step includes: when the pressure is continuously measured by distributing air to the first sensor or the second sensor, after a set pause time has passed, measuring the pressure of the first sensor and measuring the pressure of the second sensor, and comparing the pressures.

[0025] According to the present invention, when the compressor is driven, by checking the connection state of each of the air tank, the rear bumper module and the roof module with the connector using the pressure difference detected from the installed pressure sensor, the occurrence position of a fault such as leakage can be correctly diagnosed. In addition, this is achieved by diagnosing whether there is a leak in each of the pressure sensors installed on the air tank, the rear bumper module and the roof module, and when the high-pressure air supplied from the air tank is distributed to the rear bumper module or the roof module to perform cleaning.

[0026] In addition, according to the present invention, even if the outside air temperature does not change and the high-pressure clean air is not distributed, when the compressor is operated to maintain the internal pressure at a set minimum pressure or higher, it can be diagnosed that a fine leak has occurred. Therefore, it is possible to effectively determine whether a fine leak has occurred.

[0027] In addition, according to the present invention, after clean air is distributed to the rear bumper module and the roof module, when it is determined that no pressure drop is detected from the pressure sensor, it can be determined that the nozzles connected to the rear bumper module and the roof module are in a blocked state. Therefore, it is possible to diagnose whether there is a blocked state, i.e., blocked, blocked, partially blocked, etc.

[0028] It should be understood that the terms "vehicle" or "vehicle-like" or other similar terms used herein generally include motor vehicles. Such motor vehicles may include passenger cars including sports utility vehicles (SUVs), buses, trucks, various commercial vehicles, watercraft including various boats and ships, aircraft, etc. Such motor vehicles may also include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels obtained from resources other than petroleum). As described herein, a hybrid vehicle is a vehicle having two or more power sources, for example, a vehicle powered by gasoline and electricity.

[0029] The above features and other features of the present invention are discussed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and other features of the invention are described in detail with reference to certain examples of the invention, which are shown in the accompanying drawings, which are given hereinafter only by way of illustration and therefore not limiting of the invention, and in which:

[0031] Figure 1 is a schematic diagram showing a sensor cleaning system according to one embodiment of the present invention;

[0032] Figure 2 is a schematic diagram showing an outside air temperature sensor of a sensor cleaning system according to one embodiment of the present invention;

[0033] Figures 3A-3E is a graph showing pressure variation trends of an air tank, a roof module, and a rear bumper module when a leak of a sensor cleaning system according to an embodiment of the present invention is determined;

[0034] Figure 4 is a graph showing a trend of pressure change when it is determined that a sensor cleaning system according to one embodiment of the present invention is clogged;

[0035] Figure 5 is a block diagram sequentially illustrating one embodiment of a fault diagnosis method of a sensor cleaning system according to the present invention;

[0036] Figure 6 is a block diagram sequentially showing another embodiment of a fault diagnosis method of a sensor cleaning system according to the present invention; and

[0037] Figure 7 is a block diagram sequentially illustrating another embodiment of a fault diagnosis method of a sensor cleaning system according to the present invention.

[0038] It should be understood that the drawings are not necessarily drawn to scale and thus present a somewhat simplified representation of various features illustrating the basic principles of the invention. The specific design features of the present invention as described herein, including, for example, specific size, orientation, location and shape, should be determined by the specific intended application and use environment.

[0039] In the drawings, reference numbers refer to the same or equivalent parts of the present invention throughout the several views. DETAILED DESCRIPTION

[0040] Embodiments according to the present invention will be described in detail below with reference to the accompanying drawings.

[0041] Advantages and features of the present invention and methods for achieving the same will become clear with reference to the following embodiments described in detail with reference to the accompanying drawings.

[0042] When a controller, component, device, element, part, unit, module, etc. of the present invention is described as having a purpose or performing an operation, function, etc., the controller, component, device, element, part, unit or module should be considered herein as "configured to" meet the purpose or perform the operation or function. Each controller, component, device, element, part, unit or module, etc. may separately embody or include a processor and a memory, such as a non-transitory computer-readable medium, as part of the device.

[0043] However, the present invention is not limited to the embodiments disclosed below, and can be implemented in various different forms. These embodiments are provided only to make the disclosure of the present invention complete, and to fully inform the ordinary technicians of the field to which the present invention belongs. In addition, the present invention is limited only by the scope of the appended claims.

[0044] Furthermore, in the description of the present invention, in the case where it has been determined that the related known technology may obscure the gist of the present invention, the detailed description thereof is omitted.

[0045] Figure 1 is a schematic diagram showing a sensor cleaning system according to one embodiment of the present invention. Figure 2 is a schematic diagram of an outside air temperature sensor illustrating a sensor cleaning system according to an embodiment of the present invention.

[0046] also, Figures 3A-3E is a graph showing pressure variation trends of an air tank, a roof module, and a rear bumper module when a sensor cleaning system according to an embodiment of the present invention is determined to be leaking. Figure 4 is a graph showing a trend of pressure change when it is determined that the sensor cleaning system according to one embodiment of the present invention is clogged.

[0047] like Figure 1 As shown, the sensor cleaning system according to the present embodiment includes: an air tank 100 , a roof module 200 , a rear bumper module 300 , a pressure sensor 400 and a controller 500 .

[0048] The air tank 100 is formed to be filled with high-pressure air through the air flow path L1 by the compressor 1 connected by the first connector 10 and driven.

[0049] In other words, the air tank 100 is disposed in a power electric (PE) compartment located at the front side of the vehicle body together with the compressor 1. The air tank 100 is configured to be filled with high-pressure air by the compressor 1. Therefore, the air tank 100 is connected to the compressor 1 through a first connector 10 disposed along the air flow path L1.

[0050] Furthermore, the roof module 200 and the rear bumper module 300 are respectively disposed along air flow paths L3 (ie, first branch air flow path) and L4 (ie, second branch air flow path formed by branching from the air flow path L2 connected to the air tank 100 from the second connector 20).

[0051] More specifically, the roof module 200 and the rear bumper module 300 are connected to branch air flow paths L3 and L4 formed by branching from the second connector 20 through the third connector 30 and the fourth connector 40, respectively. High-pressure clean air is distributed through the branch air flow paths L3 and L4.

[0052] The roof module 200 and the rear bumper module 300 include a plurality of sensors for autonomous driving. The sensors may include, for example, radio detection and ranging (radar), light detection and ranging (LiDAR), cameras, etc. In addition, high-pressure air flowing through each of the first and second branch air flow paths L3 and L4 is sprayed to the sensor to perform cleaning.

[0053] The roof module 200 and the rear bumper module 300 are each connected to a plurality of sensors through a plurality of channels. Under the control of the dispensers 202, 302 using the controller 500, individual cleaning by spraying fluid (eg, air, etc.) is selectively performed.

[0054] The pressure sensor 400 is installed in each of the air tank 100 , the roof module 200 , and the rear bumper module 300 to measure corresponding pressures.

[0055] The controller 500 determines the pressure difference between the air tank 100, the roof module 200 and the rear bumper module 300. The controller 500 also determines the connection states of the first connector 10, the second connector 20, the third connector 30 and the fourth connector 40 based on the pressure difference between the air tank 100, the roof module 200 and the rear bumper module 300.

[0056] In other words, in a state where the distributors 202, 302 are blocked and the compressor 1 is driven, Figure 3A As shown, the pressures of the air tank 100, the roof module 200, and the rear bumper module 300 usually increase continuously. In this case, when the pressures do not increase continuously, it can be determined that a leak has occurred.

[0057] Therefore, in this embodiment, the controller 500 can determine whether a leakage occurs due to the connection state of the first connector 10 to the fourth connector 40 by utilizing the pressure difference between the air tank 100 and the rear bumper module 300, the pressure difference between the roof module 200 and the rear bumper module 300, and the pressure difference between the air tank 100 and the roof module 200.

[0058] This is because, even if the distributor 202, 302 is blocked and the compressor 1 is driven, when the high voltage is not generated, the sensor cleaning system can be diagnosed to be in a complete leakage state. Therefore, when the pressure difference is utilized, the component in a complete leakage state due to the ground fault of the connector can be correctly checked.

[0059] To this end, when it is determined that each pressure difference occurring between the air tank 100 and the rear bumper module 300, between the roof module 200 and the rear bumper module 300, and between the air tank 100 and the roof module 200 is less than a set reference pressure difference, the controller 500 first determines that a leak has occurred in the first connector 10.

[0060] In other words, Figure 3B As shown, all three pressure values ​​measured from the air tank 100, the roof module 200 and the rear bumper module 300 are, for example, between 0.5 and 0.7, and their difference is ±0.01. Therefore, it can be seen that the air supplied from the air tank 100 is distributed to the roof module 200 and the rear bumper module 300 without significant loss, so in this case, it can be determined that a leak has occurred in the first connector 10.

[0061] As mentioned above, the reason for utilizing this (pressure) difference is that errors in the absolute voltage value may occur depending on the connected power / ground state. However, by relying on this difference, relative values ​​between sensors can be identified rather than absolute values. This approach effectively solves problems associated with possible errors.

[0062] The controller 500 can determine that the first connector 10 is normal, that is, there is no leakage or blockage, by the above method, and when it is determined that the pressure difference between the air tank 100 and the rear bumper module 300 and the pressure difference between the air tank 100 and the roof module 200 exceeds the set reference pressure difference, it can be determined that a leak has occurred in the second connector 20. In addition, when it is determined that the absolute value of the pressure difference between the rear bumper module 300 and the roof module 200 is less than the set reference pressure difference, the controller 500 can determine that a leak has occurred in the second connector 20.

[0063] In other words, Figure 3C As shown, when a high pressure of, for example, 0.9 is measured from the air tank 100 and the pressure difference between the rear bumper module 300 and the roof module 200 is low, there is no problem in air distribution between the rear bumper module 300 and the roof module 200. However, if a significant pressure difference occurs between the air tank 100, the rear bumper module 300, and the roof module 200, it can be determined that a leak has occurred in the second connector 20 connected to the dash cross member.

[0064] The controller 500 may determine that the first connector 10 and the second connector 20 are in order, and when determining that the pressure detected from the roof module 200 is relatively lower than the pressure detected from the rear bumper module 300 , may determine that a leak has occurred in the third connector 30 .

[0065] In other words, Figure 3D As shown, the pressure values ​​of the air tank 100 and the rear bumper module 300 are slightly higher, for example, 0.9 and 0.7, respectively. However, when the pressure value detected by the roof module 200 is lower, especially relative to the same input pressure reference, it can be determined that a leak has occurred in the third connector 30 because only the pressure value detected from the roof module 200 is considered to be lower.

[0066] Likewise, if Figure 3E As shown, the controller 500 may determine that the first connector 10, the second connector 20, and the third connector 30 are in order. However, when it is determined that the pressure detected from the roof module 200 is relatively higher than the pressure detected from the rear bumper module 300, when the first to third connectors 10 to 30 are operating normally, a low pressure value is detected from the rear bumper module 300. Therefore, it may be determined that a leak has occurred in the fourth connector 40.

[0067] Therefore, in the present embodiment, since it can be correctly determined whether leakage occurs in the first to fourth connectors 10 to 40 for connecting a plurality of components, a failure due to leakage can be effectively diagnosed.

[0068] like Figure 2 As shown, the sensor cleaning system according to the present embodiment further includes an outside air temperature sensor 600 configured to measure the outside air temperature of the vehicle and detect a change in the outside air temperature.

[0069] More specifically, when it is determined that the compressor 1 is driven a set number of times (e.g., 3 times or more) within a set time (e.g., 5 minutes), the controller 500 can determine that a slight leak has occurred, provided that the change in the outside air temperature transmitted from the outside air temperature sensor 600 is within a set range (e.g., within 10°C) and the distributors 202, 302 for enabling air to be distributed from the roof module 200 and the rear bumper module 300 are blocked.

[0070] Generally, the controller 500 controls the compressor 1 to be driven so as to prevent the pressure drop. This is achieved when the pressure drop continues to occur due to a substantial change in the outside air temperature, when the distributor 202, 302 is blocked and the high-pressure air is not ejected to the sensor.

[0071] By using this feature, when the distributor 202, 302 is blocked and the high-pressure air is not ejected to the roof module 200 or the rear bumper module 300, and the compressor 1 is driven to prevent the pressure drop even if the change in the outside air temperature is less than the set range, it can be determined that the pressure drop continues to occur. Thus, the position of the fine leak is not determined, but it can be diagnosed whether the fine leak occurs in the air flow path.

[0072] Therefore, the controller 500 finally diagnoses that a minute leak occurs when the change in the outside air temperature transmitted from the outside air temperature sensor 600 is within 10° C., and the operation of the compressor 1 is driven 3 times or more within 5 minutes when the distributor 202 , 302 is blocked.

[0073] In addition, when it is determined that no pressure drop is detected from the pressure sensor 400 at the distribution position after the air is distributed to the rear bumper module 300 and the roof module 200, the controller 500 can diagnose that the air flow path, i.e., the nozzle connected to the rear bumper module 300 or the roof module 200 is in a clogged state.

[0074] The diagnosis of the controller 500 may be misdiagnosed by the pressure change caused by the driving or movement of the vehicle. Therefore, it is expected that the diagnosis by the controller 500 is performed in the stopped state of the vehicle. In addition, the controller 500 determines the pressure change of both the rear bumper module 300 and the roof module 200. For example, the controller 500 sequentially determines 21 channels connected to the distributors 202, 302 so that air can be distributed from the rear bumper module 300 and the roof module 200, thereby individually diagnosing the clogging status of all nozzles connected to the sensor.

[0075] The following description is made by taking the roof module 200 as an example. Figure 4 As shown, the controller 500 allows air to be continuously sprayed to the corresponding sensor through the first and second passages (P1 and P2) of the roof module 200 connected to the distributors 202 and 302. When it is determined that the spray pressure changes, that is, P1 and P2 are less than the set critical value, and there is no pressure drop even when the spraying starts, it can be diagnosed that the corresponding nozzle is clogged.

[0076] The continuous pressure measurement between the multiple channels for determining the pressure change is controlled to take place after a set pause time has elapsed.

[0077] In other words, when the clogging state of the first channel is diagnosed and the clogging state of the second channel is diagnosed without a pause time, since there is a possibility of misdiagnosis due to the diagnosis of the clogging state of the first channel, the measurement can be controlled by the controller 500 to be performed after the pause time has passed.

[0078] For example, Figure 4 As shown, when the pause time is controlled to be after the time point P1 when the air is injected into the first channel until the time point P2 when the air is injected into the second channel, since it can be confirmed that no pressure change occurs between approximately 7.9 seconds and 10.4 seconds, misdiagnosis due to pressure change during the pause time as described above can be prevented, and the blockage status of all air flow paths can be diagnosed individually.

[0079] In the following, Figure 5 1 and 2 are views sequentially illustrating an embodiment of a fault diagnosis method of a sensor cleaning system according to an embodiment of the present invention. Figure 6 1 is a view sequentially showing another embodiment of a fault diagnosis method of a sensor cleaning system according to one embodiment of the present invention. Figure 7 1 is a view sequentially showing another embodiment of a fault diagnosis method of a sensor cleaning system according to one embodiment of the present invention.

[0080] like Figure 5 As shown, the fault diagnosis method of the sensor cleaning system according to the present embodiment is described in sequence below.

[0081] When the distributors 202, 302 connected to the plurality of sensors are blocked and the compressor 1 is driven, normally, the pressures of the air tank 100, the roof module 200, and the rear bumper module 300 are continuously increased (see Figure 3A ). When there is no continuous increase in pressure, it can be determined that a complete leak has occurred.

[0082] As described above, in order to determine whether a complete leakage occurs, the controller 500 first determines whether the compressor 1 is driven (S120).

[0083] In this case, the controller 500 can use the pressure difference between the air tank 100 and the rear bumper module 300, the pressure difference between the roof module 200 and the rear bumper module 300, and the pressure difference between the air tank 100 and the roof module 200 to determine whether a leakage has occurred depending on the connection status of the first connector 10 to the fourth connector 40.

[0084] This is because, even if the distributor 202, 302 is blocked and the compressor 1 is driven, when no high voltage is generated, it is possible to diagnose that the sensor cleaning system is in a complete leakage state. Therefore, when using the pressure difference, the component in a complete leakage state due to the ground fault of the connector can be correctly checked.

[0085] To this end, when it is determined that the pressure differences between the air tank 100 and the rear bumper module 300, between the roof module 200 and the rear bumper module 300, and between the air tank 100 and the roof module 200 are all less than the set reference pressure difference, the controller 500 determines that a leak has occurred in the first connector 10 (S210).

[0086] In other words, Figure 3BAs shown, all three pressure values ​​measured from the air tank 100, the roof module 200 and the rear bumper module 300 are, for example, between 0.5 and 0.7, and their difference is ±0.01. Therefore, it can be seen that the air supplied from the air tank 100 is distributed to the roof module 200 and the rear bumper module 300 without obvious loss, so it can be determined that a leak has occurred in the first connector 10.

[0087] As described above, the reason for utilizing the (pressure) difference is that the method for detecting pressure includes a voltage value, and an error in the absolute value of the voltage itself may occur based on the connected power / ground state. However, since the (pressure) difference can be utilized to identify a relative value between sensors rather than an absolute value, the problem caused by the generation of the error can be solved.

[0088] The controller 500 can determine that the first connector 10 is normal through the above method, and when it is determined that the pressure difference between the air tank 100 and the rear bumper module 300, and the pressure difference between the air tank 100 and the roof module 200 exceed the set reference pressure difference, it is determined that a leak has occurred in the second connector 20. In addition, when the absolute value of the pressure difference between the rear bumper module 300 and the roof module 200 is less than the set reference pressure difference, the controller 500 can determine that a leak has occurred in the second connector 20 (S310).

[0089] In other words, when a high pressure of, for example, 0.9 is measured from the air tank 100 (see Figure 3C ) and the pressure difference between the rear bumper module 300 and the roof module 200 is low, there is no problem in the air distribution of the rear bumper module 300 and the roof module 200. Alternatively, it can be determined that a leak has occurred between the air tank 100, the rear bumper module 300 and the roof module 200, generating a large pressure difference therebetween. Therefore, it can be determined that a leak has occurred in the second connector 20 connected to the dash cross member.

[0090] The controller 500 may determine that the first connector 10 and the second connector 20 are in order (S200 and S300), and when it is determined that the pressure detected from the roof module 200 is lower than the pressure detected from the rear bumper module 300 (S400), determine that a leak has occurred in the third connector 30 (S410).

[0091] In other words, the pressure values ​​of the air tank 100 and the rear bumper module 300 are slightly higher, for example, 0.9 and 0.7 respectively (see Figure 3DIn the case where the pressure value detected by the roof module 200 is low, especially relative to the same input pressure reference, it can be determined that a leak has occurred in the third connector 30 because only the pressure value detected from the roof module 200 is considered to be low.

[0092] Similarly, refer to Figure 3E , the controller 500 may determine that the first connector 10, the second connector 20, and the third connector 30 are in order (S200 to S400). However, when it is determined that the pressure detected from the roof module 200 is higher than the pressure detected from the rear bumper module 300 (S500), when the first connector 10 to the third connector 30 are working normally, a low pressure value is detected from the rear bumper module 300. Therefore, it may be determined that a leak has occurred in the fourth connector 40 (S510).

[0093] like Figure 6 As shown, in the fault diagnosis method of the sensor cleaning system according to the present embodiment, when it is determined that the change in the outside air temperature transmitted from the outside air temperature sensor 600 is within a set range, for example, 10° C. (S200), it can be determined that a fine leak has occurred (S410). In addition, when the distributors 202, 302 for distributing air from the roof module 200 and the rear bumper module 300 are blocked (S100), when the controller 500 drives the compressor 1 (S300) a set number of times (for example, 3 times) or more within a set time (for example, 5 minutes) (S400), it can be determined that a fine leak has occurred (S410).

[0094] Generally, the controller 500 controls the compressor 1 to be driven to prevent the pressure drop because the pressure drop continuously occurs when the external air temperature varies greatly when the distributors 202, 302 are blocked and the high-pressure air is not sprayed to the sensor.

[0095] By using this feature, when the distributor 202, 302 is blocked, the high-pressure air is not ejected to the roof module 200 or the rear bumper module 300 (S100), and even if the change in the outside air temperature is less than the set range (S200), the compressor 1 is driven to prevent the pressure drop (S300 to S400), it can be determined that the pressure drop occurs continuously. Therefore, the position of the fine leak may not be specified, but it can be diagnosed whether the fine leak occurs on the air flow path (S410).

[0096] Therefore, when the change of the outside air temperature transmitted from the outside air temperature sensor 600 is within 10°C and the operation of the compressor 1 is driven more than 3 times within 5 minutes, the controller 500 finally diagnoses that a fine leak occurs. This diagnosis occurs when the distributor 202, 302 is blocked.

[0097] like Figure 7 As shown, after the air is distributed to the rear bumper module 300 and the roof module 200, when it is determined that no pressure drop is detected from the pressure sensor 400 at the distribution position (see Figure 4 ), the controller 500 may diagnose that the air flow path, ie, the nozzle connected to the rear bumper module 300 or the roof module 200 is in a clogged state.

[0098] Since the diagnosis of the controller 500 may be misdiagnosed due to pressure changes caused by the vehicle running, it is first determined whether the vehicle is in a stopped state (S100).

[0099] When it is determined that the vehicle is in a parking state ( S100 ), air is continuously injected to corresponding sensors through the first and second passages connected to the distributors 202 , 302 to diagnose a clogging state ( S200 and S300 ).

[0100] When the first channel and the second channel (i.e. Figure 4 When the pressure change between the time points P1 and P2 in the flow chart is less than a set critical value (S400), the controller 500 can diagnose that the corresponding nozzle is clogged (S410).

[0101] In other words, in a normal state, when air is continuously ejected through the first and second passages connected to the distributors 202, 302, the change in ejection pressure between time points P1 and P2 should exceed the set critical value, that is, a pressure drop should occur. However, in a blocked state, the pressure change between time points P1 and P2 becomes smaller than the set critical value (see Figure 4 ).

[0102] Therefore, when there is no pressure drop even though air is injected to the first and second passages connected to the distributors 202 and 302, it can be diagnosed that the nozzle is clogged.

[0103] The controller 500 determines all pressure changes of the rear bumper module 300 and the roof module 200. Specifically, the controller 500 sequentially determines all pressure changes in 21 channels (i.e., consecutive channels such as the third channel and the fourth channel) connected to the distributors 202, 302 to enable air to be distributed in the rear bumper module 300 and the roof module 200. This sequential check facilitates individual diagnosis of the clogging status of all nozzles connected to the sensor (S500).

[0104] The continuous pressure measurement between the plurality of channels for determining the pressure change is controlled to take place after a set pause time has elapsed.

[0105] In other words, when the clogging state of the first channel is diagnosed and the clogging state of the second channel is diagnosed without a pause time, since there is a possibility of misdiagnosis due to the diagnosis of the clogging state of the first channel, the measurement can be controlled by the controller 500 to be performed after the pause time has passed.

[0106] For example, when the pause time is controlled to be after the time point P1 when the air is injected into the first channel until the time point P2 when the air is injected into the second channel, it can be confirmed that no pressure change occurs between about 7.9 seconds and 10.4 seconds (see Figure 4 ). As described above, this measurement helps prevent misdiagnosis due to pressure changes during the pause time, thereby ensuring accurate individual diagnosis of the blockage status of all air flow paths.

[0107] According to the present invention, the location where a fault such as leakage occurs can be correctly diagnosed by checking the connection state of each of the air tank, the rear bumper module, and the roof module with the connector. This is achieved by using the pressure difference detected from the installed pressure sensor when the compressor is driven. Whether there is a leak is diagnosed by using a pressure sensor on each of the air tank, the rear bumper module, and the roof module, where high-pressure air supplied from the air tank is distributed to the rear bumper module and the roof module for cleaning.

[0108] In addition, according to the present invention, even if the outside air temperature does not change and the high-pressure clean air is not distributed, when the compressor is operated to maintain the internal pressure at a set minimum pressure or higher, it can be diagnosed that a fine leak has occurred. Therefore, it is possible to effectively determine whether a fine leak has occurred.

[0109] In addition, according to the present invention, after clean air is distributed to the rear bumper module and the roof module, when it is determined that no pressure drop is detected from the pressure sensor, it can be determined that the nozzles connected to the rear bumper module and the roof module are in a clogged state, and thus it can be diagnosed whether the clogged state exists.

[0110] The present invention has been described above with reference to the embodiments shown in the accompanying drawings. However, it should be understood that this is merely illustrative, and a person skilled in the art may make various modifications according to the present invention. All or part of the above embodiments may also be configured in their selective combination. Therefore, the actual protection scope of the present invention should be determined by the technical spirit of the appended claims.

Claims

1. A sensor cleaning system, comprising: an air tank connected to the compressor via a first connector and configured to be filled with high-pressure air from the compressor; Roof module; Rear bumper module; an air flow path connected to the air tank and branched into a first branch air flow path and a second branch air flow path through a second connector, wherein the first branch air flow path is connected to the roof module through a third connector, and the second branch air flow path is connected to the rear bumper module through a fourth connector; a pressure sensor mounted on each of the air tank, the roof module, and the rear bumper module and configured to measure the pressure of each; and A controller is configured to determine connection states of the first connector, the second connector, the third connector, and the fourth connector by pressure differences among the air tank, the roof module, and the rear bumper module.

2. The sensor cleaning system according to claim 1, wherein: The controller is further configured to: When it is determined that the pressure does not continuously increase in the state where the compressor is driven, it is determined whether leakage depending on the connection state of the first connector to the fourth connector occurs using the pressure difference between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module.

3. The sensor cleaning system according to claim 2, wherein: The controller is further configured to: When it is determined that each of the pressure differences between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module is less than a set reference pressure difference, it is determined that a leak has occurred in the first connector.

4. The sensor cleaning system according to claim 2, wherein: The controller is further configured to: When it is determined that: i) the first connector is not leaking or blocked; ii) the pressure difference between the air tank and the rear bumper module and the pressure difference between the air tank and the roof module exceed the set reference pressure difference; and iii) the absolute value of the pressure difference between the rear bumper module and the roof module is less than the set reference pressure difference, it is determined that a leak has occurred in the second connector.

5. The sensor cleaning system according to claim 2, wherein: The controller is further configured to: When it is determined that the first connector and the second connector are not leaking or blocked, and the pressure detected from the roof module is less than the pressure detected from the rear bumper module, determining that a leak has occurred in the third connector; and When it is determined that the pressure detected from the roof module is greater than the pressure detected from the rear bumper module, it is determined that a leak has occurred in the fourth connector. 6 . The sensor cleaning system of claim 1 , further comprising an outside air temperature sensor configured to measure an outside air temperature of the vehicle and detect a change in the outside air temperature.

7. The sensor cleaning system according to claim 6, wherein: The controller is configured to: When it is determined that a change in the outside air temperature transmitted from the outside air temperature sensor is within a set range, and when the compressor is driven a set number of times or more within a set time when a distributor configured to enable air to be distributed from the roof module and the rear bumper module is blocked, it is determined that a fine leak has occurred.

8. The sensor cleaning system of claim 1, wherein: The controller is configured to: When it is determined that no pressure drop is detected from the pressure sensor after distributing air to the roof module and the rear bumper module, it is determined that the first and second branch air flow paths respectively connected to the roof module and the rear bumper module are in a blocked state.

9. The sensor cleaning system of claim 8, wherein: The controller is configured to: All pressure changes of the rear bumper module and the roof module are determined, and the blockage states of all the first branch air flow paths and the second branch air flow paths connected to the roof module and the rear bumper module are individually diagnosed.

10. The sensor cleaning system of claim 9, wherein: The controller is configured to: When it is determined that the measured pressure change between the rear bumper module and the roof module is less than a set critical value, determining that the first branch air flow path and the second branch air flow path are in a blocked state; and After a set pause time has passed, the pressure sensor is controlled to measure the pressure of the rear bumper module and the roof module to determine a pressure change.

11. A method for diagnosing a fault in a sensor cleaning system, the method comprising: The first operation step: the controller determines whether the compressor is driven; as well as The second operation step: when it is determined that the pressure does not increase continuously when the compressor is driven, the controller determines the leakage of the first connector, the second connector, the third connector or the fourth connector installed in the air flow path connecting the air tank, the front panel cross beam, the roof module and the rear bumper module through the pressure difference between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module.

12. The method according to claim 11, wherein: The second operation step includes determining that a leak has occurred in the first connector when it is determined that each pressure difference between the air tank and the rear bumper module, between the roof module and the rear bumper module, and between the air tank and the roof module is less than a set reference pressure difference.

13. The method according to claim 11, wherein: The second operation step includes: determining that a leak has occurred in the second connector when it is determined that: i) the first connector is not leaking or blocked; ii) the pressure difference between the air tank and the rear bumper module, and the pressure difference between the air tank and the roof module exceed a set reference pressure difference; and iii) the absolute value of the pressure difference between the rear bumper module and the roof module is less than the set reference pressure difference.

14. The method according to claim 11, wherein: The second operation step comprises: When it is determined that the first connector and the second connector are not leaking or blocked, and the pressure detected from the roof module is less than the pressure detected from the rear bumper module, determining that a leak has occurred in the third connector; and When it is determined that the pressure detected from the roof module is greater than the pressure detected from the rear bumper module, it is determined that a leak has occurred in the fourth connector.

15. The method according to claim 11, wherein: The second operation step comprises: When it is determined that: i) a change in the outside air temperature transmitted from the outside air temperature sensor is within a set range, and ii) the compressor is driven more than a set number of times within a set time when a distributor configured to enable air to be distributed from the roof module and the rear bumper module is blocked, it is determined that a fine leak has occurred.

16. A method for diagnosing a fault in a sensor cleaning system, the method comprising: A first operation step: in a stopped state of the vehicle, when it is determined that no pressure drop is detected from the plurality of pressure sensors after air is distributed to the rear bumper module and the roof module, diagnosing, by the controller, that the air flow path is blocked; A second operation step: in the rear bumper module or the roof module diagnosed as being clogged, measuring pressure by the controller by distributing air to a first sensor among a plurality of pressure sensors connected to a corresponding first channel among a plurality of channels, and measuring pressure by distributing air to a second sensor among a plurality of pressure sensors connected to a corresponding second channel among a plurality of channels, and comparing the measured pressures; as well as The third operation step: when it is determined that the pressure change of the first sensor and the second sensor in the rear bumper module or the roof module is less than a set critical value, the controller finally diagnoses the blockage state of the second channel.

17. The method according to claim 16, wherein: The third operation step comprises: All pressure changes in a plurality of channels connected to a plurality of sensors in the rear bumper module or the roof module are determined, and blockage states of all channels connected to the plurality of sensors in the rear bumper module or the roof module are individually diagnosed.

18. The method according to claim 16, wherein: The second operation step comprises: When the pressure is continuously measured by distributing air to the first sensor or the second sensor, after a set pause time has passed, the pressure of the first sensor is measured and the pressure of the second sensor is measured, and the pressures are compared.

Images