Apparatus and method for controlling air suspension of a vehicle

Abstract

Disclosed are an apparatus and a method of controlling an air suspension of a vehicle. The apparatus includes a compressor configured to supply compressed air, a reservoir configured to store the compressed air supplied from the compressor and supply the stored compressed air to the air suspension during vehicle height control, a road information provider configured to provide road condition information of a road ahead of the vehicle during travel of the vehicle, and a controller configured to determine a vehicle height control position of the air suspension based on the road condition information and operate the compressor before the vehicle reaches the determined vehicle height control position, thereby filling the reservoir with the compressed air such that an internal pressure of the reservoir reaches at least a predetermined reference pressure.

Description

TECHNICAL FIELD

[0001] The present application relates to an apparatus and method for controlling an air suspension of a vehicle. BACKGROUND

[0002] Generally, a suspension applying a stainless steel spring has limitations in satisfying both ride comfort and handling stability at the same time. For example, when the stainless steel spring is set to be soft, the handling stability is reduced. On the other hand, when the stainless steel spring is set to be hard in order to enhance the handling stability, the ride comfort is degraded. That is, in the case of a suspension applying a soft stainless steel spring, the spring can easily absorb an impact caused by a rough road surface, and thus, the ride comfort can be improved. However, in this case, the vehicle body can be unstable, and thus, the handling stability can be degraded. On the other hand, in the case of a suspension applying a hard stainless steel spring, the vehicle body can be stable, and thus, the handling stability can be improved. However, in this case, it can be difficult to effectively absorb an impact transmitted from a road unevenness, and thus, the ride comfort can be degraded.

[0003] In order to eliminate the drawbacks of the suspension using the above-described stainless steel spring, an air suspension using an air spring has been developed. The air spring can be hardened or softened by appropriately controlling the air pressure therein. Specifically, the air spring applied to the air suspension can also adjust the height of the vehicle body (vehicle height) by controlling the air pressure therein.

[0004] In a conventional case, the adjustment of the vehicle height using the air spring can be achieved by storing air of a sufficient pressure in a reservoir by using a compressor configured to generate compressed air, and supplying the high-pressure air from the reservoir to the air spring. In addition, when the pressure in the reservoir is insufficient, the compressor is controlled to operate to supply the air stored in the reservoir to the air spring.

[0005] However, under the condition that the pressure in the reservoir is insufficient, the pressure of the air supplied to the air spring by the compressor is insufficient. Thus, the vehicle height control time is delayed, and thus, there can be a problem in that the vehicle height control cannot be completed at an appropriate time.

[0006] The above-described information disclosed in this section is only for the purpose of enhancing the understanding of the overall background of the present application, and should not be regarded as a recognition or any form of suggestion of the related art that has been known to those skilled in the art. SUMMARY

[0007] The present invention relates to an apparatus and method for controlling an air suspension of a vehicle. The present invention relates to an apparatus and method for controlling an air suspension of a vehicle, which can pre-secure a reservoir pressure based on a driving position of the vehicle, thereby enabling the use of the air suspension to increase a vehicle height at an appropriate time.

[0008] Embodiments of the present invention provide an apparatus and method for controlling an air suspension of a vehicle, which can determine a time at which a vehicle height needs to be increased, and can secure a sufficient reservoir pressure based on the determined time, so as to enable effective vehicle height control using the air suspension at an appropriate time.

[0009] According to embodiments of the present invention, the above and other objects can be achieved by providing an apparatus for controlling an air suspension of a vehicle, including: a compressor configured to supply compressed air; a reservoir configured to store the compressed air supplied from the compressor and supply the stored compressed air to the air suspension during vehicle height control; a road information provider configured to provide road condition information of a road located ahead of the vehicle during driving of the vehicle; and a controller configured to determine a vehicle height control position of the air suspension based on the road condition information, and operate the compressor before the vehicle reaches the determined vehicle height control position, thereby filling the reservoir with the compressed air such that an internal pressure of the reservoir becomes greater than or equal to a predetermined reference pressure.

[0010] The controller can calculate a distance between a current position of the vehicle and the vehicle height control position of the air suspension, and operate the compressor when the distance between the current position of the vehicle and the vehicle height control position is less than a predetermined first reference distance, thereby filling the reservoir with the compressed air such that the internal pressure of the reservoir becomes greater than or equal to the predetermined reference pressure.

[0011] The controller can check the internal pressure of the reservoir when the distance between the current position of the vehicle and the vehicle height control position of the air suspension is less than the predetermined first reference distance, and can operate the compressor when the internal pressure of the reservoir is lower than the predetermined reference pressure, thereby filling the reservoir with the compressed air.

[0012] The reference pressure can be higher than a recommended minimum pressure of the reservoir determined based on a pressure specified in a specification of an air spring provided in the air suspension.

[0013] The controller can control the reservoir to supply air to the air suspension when the distance between the current position of the vehicle and the vehicle height control position of the air suspension is less than a predetermined second reference distance, the predetermined second reference distance being less than the first reference distance.

[0014] According to another embodiment of the present application, there is provided a method for controlling an air suspension of a vehicle, the air suspension including a compressor configured to supply compressed air, and a reservoir configured to store the compressed air supplied from the compressor and supply the stored compressed air to an air spring during vehicle height control. The method includes determining whether vehicle height control is required based on road condition information, calculating a distance from a current position of the vehicle to a position at which vehicle height control is required when it is determined that vehicle height control is required, and filling the reservoir with compressed air by operation of the compressor so that an internal pressure of the reservoir becomes greater than or equal to a predetermined reference pressure when it is determined that the distance from the current position of the vehicle to the vehicle height control position is less than a predetermined first reference distance.

[0015] Filling the reservoir with compressed air can include checking the internal pressure of the reservoir when the distance between the current position of the vehicle and the vehicle height control position of the air suspension is less than the predetermined first reference distance, and operating the compressor to fill the reservoir with compressed air when the internal pressure of the reservoir is lower than the predetermined reference pressure.

[0016] The reference pressure can be higher than a recommended minimum pressure of the reservoir determined based on a pressure specified in a specification of the air spring provided in the air suspension.

[0017] The method can further include controlling the reservoir to supply air to the air spring when the distance between the current position of the vehicle and the vehicle height control position of the air suspension is less than a predetermined second reference distance, the second reference distance being less than the first reference distance.

[0018] The air suspension control apparatus and method according to the embodiment of the present application can achieve stable vehicle height control by determining a vehicle height increase position by using a camera or navigation to previously determine an obstacle existing in front of the vehicle during travel of the vehicle or a road surface condition of a road in front of the vehicle, and securing sufficient internal pressure of the reservoir by considering operation of the compressor performed from a remaining distance to the vehicle height increase position from the current position of the vehicle.

[0019] Accordingly, according to the air suspension control apparatus and method, not only can ride comfort of the vehicle be enhanced, but also discomfort experienced by a passenger of the vehicle can be reduced. BRIEF DESCRIPTION OF DRAWINGS

[0020] The above and other objects, features and other advantages of the present application will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0021] Figure 1 is a block diagram illustrating a coasting regeneration torque application apparatus of a vehicle according to an embodiment of the present application; and

[0022] Figure 2 is a flowchart illustrating an air suspension control method according to an embodiment of the present application using the above-described air suspension control apparatus.

[0023] Effects obtainable in embodiments of the present application are not limited to the above-described effects, and other effects of the present application not described above will be more clearly understood from the following detailed description. DETAILED DESCRIPTION

[0024] Hereinafter, an apparatus and a method for controlling an air suspension according to various embodiments of the present application will be described with reference to the accompanying drawings.

[0025] Figure 1 is a block diagram illustrating a coast regeneration torque application apparatus of a vehicle according to an embodiment of the present application.

[0026] Referring to Figure 1 , the coast regeneration torque application apparatus of a vehicle according to the illustrated embodiment of the present application can include a compressor 10 configured to supply compressed air, and a reservoir 30 configured to store the compressed air supplied from the compressor 10 and supply the stored compressed air to an air spring 20 reservoir of an air suspension during vehicle height control. The coast regeneration torque application apparatus can further include a road information provider 50 configured to provide information of a road ahead of the vehicle during travel of the vehicle, and a controller 100 configured to determine a vehicle height control position of the air suspension based on the road information, and operate the compressor 10 before the vehicle reaches the determined vehicle height control position, thereby filling the reservoir 30 with the compressed air such that an internal pressure of the reservoir 30 becomes greater than or equal to a predetermined reference pressure.

[0027] The compressor 10 is a device configured to blow ambient air at high pressure using a high-speed motor. The compressed air supplied according to the operation of the compressor 10 is stored in the reservoir 30.

[0028] The reservoir 30 is a kind of tank body configured to store the compressed air supplied from the compressor 10 at high pressure. The pressure of the air stored in the reservoir 30 can be controlled to be maintained at greater than or equal to a predetermined reference pressure, to enable stable control of the air spring 20 of the air suspension at a desired time.

[0029] To this end, a pressure sensor 40 configured to measure the internal pressure of the reservoir 30 can be provided. The pressure sensor 40 can be installed at various positions according to various vehicles. In Figure 1In the middle, an example in which the pressure sensor 40 is directly installed at the reservoir 30 is shown. However, in another example, the pressure sensor 40 can be installed at an air delivery line between the reservoir 30 and the air spring 20, and thus can detect the internal pressure of the reservoir 30 according to the opening / closing state of the valves 51 and 52. In this case, for example, when the valve 51 installed on the reservoir 30 side is opened and the valve 52 installed on the air spring 20 side is closed, the pressure sensor 40 installed on the air delivery line between the reservoir 30 and the air spring 20 can measure the internal pressure of the reservoir 30. On the other hand, when the valve 51 installed on the reservoir 30 side is closed and the valve 52 installed on the air spring 20 side is opened, the pressure sensor 40 installed at the air delivery line between the reservoir 30 and the air spring 20 can measure the internal pressure of the air spring 20.

[0030] The road information provider 50 is an element configured to provide road information in front of the vehicle during travel of the vehicle. The road information provider 50 can be implemented by, for example, a camera installed in the vehicle to photograph an image of the front of the vehicle or a navigation. The road information provider 50 can detect the presence of an irregularity or an obstacle on a road in front of the vehicle, such as a speed bump. Such an irregularity or speed bump corresponds to a position at which the vehicle height of the vehicle should be increased by supplying air to the air spring 20 of the air suspension. The road information identified by the road information provider 50 can be provided to the controller 100.

[0031] The controller 100 can determine a position at which the vehicle height control is required based on the information about the irregularity position or the obstacle position provided by the road information provider 50. Then, the controller 100 can operate the compressor 10 so as to fill the reservoir 30 with compressed air such that the internal pressure of the reservoir 30 becomes greater than or equal to the predetermined reference pressure before the vehicle reaches the position at which the vehicle height control is required.

[0032] According to the exemplary embodiment of the present application, the controller 100 can be implemented by a non-volatile storage (not shown) configured to store data configured as an algorithm to control the operation of various constituent elements of the vehicle, or software commands regarding execution of the algorithm, and a processor (not shown) configured to execute the operation using the data stored in the storage as described below. Here, the storage and the processor can be implemented as separate chips, respectively. Alternatively, the storage and the processor can be implemented as a single unified chip. The processor can take the form of one or more processors.

[0033] The controller 100 can use the information on the road surface condition and the obstacle position provided by the road information provider 50 to calculate the distance from the current position of the vehicle to the vehicle height control position. For example, the controller 100 can determine whether the road surface condition or the obstacle position provided by the road information provider 50 is an object requiring an increase in the vehicle height. When it is determined that the road surface condition or the obstacle position is an object requiring an increase in the vehicle height, the controller 100 can calculate the distance from the current position of the vehicle to the vehicle height increase position.

[0034] In addition, when the remaining distance from the current position of the vehicle to the vehicle height increase position is less than a predetermined first reference distance, the controller 100 can check the internal pressure of the reservoir 30. When the internal pressure of the reservoir 30 is lower than a predetermined reference pressure, the controller 100 can operate the compressor 10 to fill the reservoir 30 with compressed air such that the internal pressure of the reservoir 30 is sufficiently increased.

[0035] On the other hand, when the vehicle approaches the vehicle height increase position, such that the remaining distance from the current position of the vehicle to the vehicle height increase position is less than a predetermined second reference distance, which is less than the predetermined first reference distance, the valves 51 and 52 installed between the reservoir 30 and the air springs 20 of the air suspension can be opened, thereby supplying high-pressure air to the air springs 20 to increase the vehicle height.

[0036] Here, preferably, the reference pressure is higher than a recommended minimum pressure for the reservoir 30 as a reference for determining whether the compressor 10 should be operated to fill the reservoir 30 with air. For example, when the pressure recommended for proper supply of air to the air springs 20 is a minimum of 12 bar, the reference pressure is preferably about 15 bar to be higher than the minimum required pressure.

[0037] The recommended pressure of the reservoir 30 can be determined according to the specifications of the air springs 20. For example, when the required pressure determined in the specifications of the air springs 20 is 8 to 10 bar, the recommended pressure of the reservoir 30 can be determined to be 12 to 18 bar, which is higher than the maximum pressure determined in the specifications of the air springs 20.

[0038] In the embodiment of the present application, the controller 100 can perform control to pre-fill the reservoir 30 with air at a pressure higher than the recommended minimum pressure of the reservoir 30, so that air is more quickly supplied to the air springs 20 at a position requiring an increase in the vehicle height. Accordingly, a rapid increase in the vehicle height can be achieved. At the same time, even when unexpected vehicle height control frequently occurs, since the predetermined reservoir pressure can always be ensured, the time taken for subsequent vehicle height control can be reduced.

[0039] Figure 2is a flowchart showing an air suspension control method according to an embodiment of the present application using the above-described air suspension control apparatus.

[0040] With reference to Figure 2 The air suspension control method according to the illustrated embodiment of the present application can start from step Sll, in which the controller 100 receives road condition information of a road ahead of the vehicle during vehicle travel when the road information provider 50 provides the road condition information, the controller 100 checks whether the road condition information includes unevenness or an obstacle based on the road condition information, and the controller 100 determines whether the vehicle height of the vehicle should be increased by supplying air to the air springs 20 in the air suspension of the vehicle based on the checked road condition information.

[0041] Thereafter, when it is determined based on the road condition information that there is an object requiring vehicle height increase, the controller 100 can identify the position of the object requiring vehicle height increase, and can calculate a remaining distance from the current position of the vehicle to the position of the object requiring vehicle height increase (S12).

[0042] The remaining distance calculation in step S12 can be performed using techniques known in the art to which the present application pertains. For example, when the road information provider 50 is a camera, the remaining distance can be calculated by analyzing the positions of objects such as lane marking lines, boulevards, or street lamps present in an image taken by the camera as a reference, and analyzing the position of the object requiring vehicle height increase (unevenness or an obstacle). In another example, when the road information provider 50 is a navigation, the remaining distance from the current position of the vehicle to the object requiring vehicle height increase can be derived.

[0043] Subsequently, upon determining that the remaining distance from the current position of the vehicle to the object requiring vehicle height increase is less than a predetermined first reference distance A (S13), the controller 100 can check the internal pressure of the reservoir 30. When the internal pressure of the reservoir 30 is lower than a predetermined reference pressure B (S14), the controller 100 can then operate the compressor 10 to fill the reservoir 30 with air such that the internal pressure of the reservoir 30 is sufficiently increased (S15). When the internal pressure of the reservoir 30 is not lower than the predetermined reference pressure B (NO at S14), the method can bypass S15.

[0044] Thereafter, when the remaining distance from the current position of the vehicle to the vehicle height increase position is less than a predetermined second reference distance C, which is smaller than the predetermined first reference distance A, when the vehicle moves very close to the vehicle height increase position (S16), the controller 100 opens the valves 51 and 52 installed between the reservoir 30 and the air springs 20 of the air suspension, thereby supplying high-pressure air to the air springs 20 to increase the vehicle height (S17).

[0045] As is apparent from the foregoing description, the air suspension control apparatus and method of the embodiments of the present application can achieve stable vehicle height control by determining a vehicle height increase position by using a camera or navigation to determine an obstacle present in front of the vehicle during travel of the vehicle or a road surface state of a road in front of the vehicle in advance, and securing sufficient internal pressure of the reservoir by considering operation of the compressor performed from a remaining distance to the vehicle height increase position from a current position of the vehicle. Accordingly, according to the air suspension control apparatus and method, not only can ride comfort of the vehicle be improved, but also discomfort of a passenger of the vehicle can be reduced.

[0046] While preferred embodiments of the present application have been disclosed in detail above, it will be understood by those skilled in the art that various modifications, additions and substitutions can be made hereto without departing from the scope and spirit of the application as disclosed in the accompanying claims.

Claims

1. A device for controlling an air suspension system of a vehicle, the device comprising: The compressor is configured to supply compressed air; A storage unit is configured to store the compressed air supplied from the compressor and to supply the stored compressed air to the air suspension during vehicle height control. A road information provider is configured to provide road condition information of the road ahead of the vehicle during the vehicle's travel. as well as The controller is configured to determine the vehicle height control position of the air suspension based on the road condition information, and to operate the compressor before the vehicle reaches the determined vehicle height control position, thereby filling the reservoir with compressed air such that the internal pressure of the reservoir reaches at least a predetermined reference pressure. The controller is configured to: calculate the distance between the current position of the vehicle and the vehicle height control position of the air suspension; and operate the compressor when the distance between the current position of the vehicle and the vehicle height control position is less than a predetermined first reference distance, thereby filling the reservoir with compressed air such that the internal pressure of the reservoir reaches at least the predetermined reference pressure. The controller is configured to supply compressed air to the air suspension when the distance between the current position of the vehicle and the vehicle height control position of the air suspension is less than a predetermined second reference distance, wherein the predetermined second reference distance is less than the predetermined first reference distance.

2. The device according to claim 1, wherein, The controller is configured to: check the internal pressure of the reservoir when the distance between the current position of the vehicle and the vehicle height control position of the air suspension is less than the predetermined first reference distance, and operate the compressor to fill the reservoir with compressed air when the internal pressure of the reservoir is lower than the predetermined reference pressure.

3. The device according to claim 2, wherein, The reference pressure is higher than the recommended minimum pressure of the storage device, which is determined based on the pressure specified in the specifications of the air springs installed in the air suspension.

4. A method for controlling an air suspension of a vehicle, the air suspension comprising a compressor configured to supply compressed air and a reservoir configured to store compressed air supplied from the compressor and supply the stored compressed air to an air spring during vehicle height control, the method comprising: Based on road condition information, determine whether vehicle height control is required; When it is determined that vehicle height control is required, the distance from the vehicle's current position to the vehicle height control position is calculated; When it is determined that the distance from the current position of the vehicle to the vehicle height control position is less than a predetermined first reference distance, the reservoir is filled with compressed air by operating the compressor, such that the internal pressure of the reservoir reaches at least a predetermined reference pressure; and When the distance between the current position of the vehicle and the vehicle height control position is less than a predetermined second reference distance, the storage device is controlled to supply compressed air to the air spring, wherein the predetermined second reference distance is less than the predetermined first reference distance.

5. The method according to claim 4, wherein, Filling the reservoir with the compressed air includes: When the distance between the vehicle's current position and the vehicle height control position is less than the predetermined first reference distance, the internal pressure of the storage device is checked; and The compressor is operated when the internal pressure of the reservoir is lower than the predetermined reference pressure, thereby filling the reservoir with compressed air.

6. The method according to claim 4, wherein, The predetermined reference pressure is higher than the recommended minimum pressure of the storage device, which is determined based on the pressure specified in the specifications of the air spring located at the air suspension.

7. A method for controlling an air suspension system in a vehicle, the method comprising: Compressed air is stored in a storage tank; Determine if vehicle height control is required; When it is determined that vehicle height control is required, the distance from the first position of the vehicle to the vehicle height control position is calculated; Determine whether the calculated distance is less than a predetermined first reference distance; When it is determined that the calculated distance is less than the predetermined first reference distance, check the internal pressure of the storage device; When it is determined that the internal pressure of the reservoir is lower than a predetermined reference pressure, the reservoir is filled with additional compressed air so that the internal pressure of the reservoir reaches at least the predetermined reference pressure. Then, when it is determined that vehicle height control is required, Calculate the remaining distance from the second position of the vehicle to the vehicle height control position; and When the remaining distance is less than a predetermined second reference distance, the compressed air in the storage device is supplied to the air spring, wherein the predetermined second reference distance is less than the predetermined first reference distance.

8. The method according to claim 7, wherein, Determining whether the vehicle height control is needed includes: Receive road condition information of the road ahead of the vehicle; Check whether the road condition information includes unevenness or obstacles; and Based on the road condition information examined, it is determined whether the vehicle height should be increased.

9. The method according to claim 8, wherein, The vehicle height control position includes: the uneven position or the position of the obstacle included in the road condition information.

10. The method according to claim 7, wherein, The predetermined reference pressure is higher than the recommended minimum pressure of the storage device.

11. The method according to claim 10, wherein, The recommended minimum pressure of the reservoir is determined based on the pressure specified in the specifications of the air springs located at the air suspension.

12. The method according to claim 7, wherein, Supplying the compressed air from the reservoir to the air spring includes: opening at least one valve installed between the reservoir and the air spring.

13. The method according to claim 7, wherein, The compressed air in the reservoir is supplied to the air spring, which increases the height of the vehicle.

14. The method of claim 7, wherein when the internal pressure of the storage device is not lower than the predetermined reference pressure, Calculate the remaining distance from the second position of the vehicle to the vehicle height control position; and When the remaining distance is less than a predetermined second reference distance, the vehicle height is increased.

15. The method according to claim 14, wherein, Increasing the vehicle height includes supplying compressed air from the reservoir to the air spring by opening at least one valve installed between the reservoir and the air spring.

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