Pedestrian protection apparatus of vehicle

A pedestrian protection apparatus of a vehicle includes a first pressure sensor installed at a first side of a front side of the vehicle and a second pressure sensor installed at a second side of the front side of the vehicle. A hollow tube extends between and is connected with each of the first and second pressure sensors. A control unit is configured to receive pressure values output by the first and second pressure sensors and determine whether a collision object is a pedestrian based on the received pressure values.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from and the benefit of Korean Patent Application Number 10-2014-0043221, filed on Apr. 10, 2014, which is hereby incorporated by reference for all purposes as if fully set forth herein.

BACKGROUND

Field

Exemplary embodiments relate to a pedestrian protection apparatus of a vehicle, and more particularly, to a pedestrian protection apparatus of a vehicle that determines a type and a position of an object colliding with the vehicle.

SUMMARY

Exemplary embodiments provide a pedestrian protection apparatus of a vehicle.

Exemplary embodiments provide a pedestrian protection apparatus of a vehicle that senses a change in gas pressure in a tube in a pedestrian protection apparatus installed on the vehicle to protect the pedestrian. The pedestrian protection apparatus determines a collision position of an object, and accurately determines whether the collision is with a pedestrian so as to perform an operation to protect the pedestrian.

An exemplary embodiment of the present invention discloses a pedestrian protection apparatus of a vehicle, including: a hollow tube connected with each of a plurality of pressure sensors; and a control unit configured to determine whether a collision object is a pedestrian based on a plurality of pressure values received from the plurality of pressure sensors.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

Hereinafter, the present invention will be described with reference to drawings for describing a pedestrian protection apparatus of a vehicle by exemplary embodiments of the present invention.

FIG. 1Ais a front view of a pedestrian protection apparatus of a vehicle according to an exemplary embodiment of the present invention.FIG. 1Bis a sectional view of a pedestrian protection apparatus of a vehicle according to an exemplary embodiment of the present invention.FIG. 2is a front view of the pedestrian protection apparatus of a vehicle according to the exemplary embodiment of the present invention.

The pedestrian protection apparatus of a vehicle according to the preferred embodiment may be modified by those skilled in the art and in the exemplary embodiment of the present invention, the pedestrian protection apparatus is preferred.

Referring toFIGS. 1A, 1B, and 2, the pedestrian protection apparatus of a vehicle according to the exemplary embodiment of the present invention includes a plurality of pressure sensor modules100installed at both sides of a front bumper500of the vehicle and a tube200disposed between the plurality of pressure sensor modules100and connected with the plurality of respective pressure sensor modules100. The tube200is hollow and flexible or compressible (i.e., crushable) such that upon external contact with an object, gas flows into the respective pressure sensor modules100.

The plurality of pressure sensor modules100may be installed at both sides of a front cross member300of the vehicle, but the present invention is not limited thereto and the plurality of pressure sensor modules100may be installed at both sides, and may include other elements such as foam400, a sensor bumper fascia, and the like in the bumper500of the vehicle. Each of the plurality of pressure sensor modules100is connected with the hollow tube200, respectively. The plurality of pressure sensor modules100may be directly connected with both sides of the tube200and the plurality of pressure sensor modules100may be connected with the both sides of the tube200with another member inserted therebetween.

A pressure sensor may be provided inside a casing of the pressure sensor module100. In more detail, the pressure sensor may be disposed below the casing in order to precisely sense a change amount of internal pressure, but the present invention is not limited thereto. In this case, the pressure sensor may be positioned below the tube200.

Referring toFIG. 2, the hollow tube200, in which gas can flow, is disposed between the plurality of pressure sensor modules100(100a,100b) and connected with each of the plurality of pressure sensor modules100a,100b.

The diameter of an inlet end connected with the tube200of the pressure sensor module100may be larger or smaller than that of the tube, and as a result, the diameter is not limited to any particular size. The pressure sensor module100may determine the pressure of the gas in the tube and transmit information on the pressure to a control unit.

The pressure sensor module100may include the pressure sensor therein. The pressure sensor may derive a pressure value indicating the pressure of the gas in the tube and provide the derived pressure value to the control unit. The control unit receives pressure values from two pressure sensors and may determine a type and/or a position of the object colliding with the vehicle based on the received pressure values.

FIG. 3is a block diagram illustrating components of the pedestrian protection apparatus of a vehicle according to the exemplary embodiment of the present invention.FIG. 4is a flowchart illustrating a method for controlling a pedestrian protection apparatus of a vehicle according to another exemplary embodiment of the present invention.

Referring toFIGS. 3 and 4, the pedestrian protection apparatus of a vehicle according to the exemplary embodiment of the present invention may include a plurality of pressure sensors30installed at both sides of a front side of the vehicle and a control unit10connected with each of the plurality of pressure sensors30and configured to determine a collision position with an external object based on a plurality of pressure values received from the hollow tube and the plurality of pressure sensors30.

The control unit10may control various components of the vehicle. For example, the control unit10receives the pressure values from the plurality of pressure sensors30and may determine what the object colliding with the vehicle is based on the received pressure values.

The control unit10may receive the pressure value from the pressure sensor30(S10). The control unit10may determine which position of the front side of the vehicle the collision occurs at, from the plurality of pressure values received from the plurality of pressure sensors30. The control unit10may have an output signal of the pressure sensor30, which is controlled without noise as an input, by using a low pass filter (not shown).

The control unit10determines a pressure value indicating a change in pressure of the gas in the tube connected with the pressure sensor30to determine a mass of the collision object. The control unit10may determine whether the collision object is a pedestrian by taking into consideration the speed of the vehicle, the collision position, and the like.

The control unit10may determine the collision position by differences among points of time when the pressure values are received from the plurality of pressure sensors30(S20). The control unit10may determine the points of time when the pressure values are received from the plurality of pressure sensors30. When the control unit10receives the plurality of pressure values, the control unit10may determine the respective received points of time and determine intervals among time among the points of time. The control unit10may then determine the position based upon the known positions of the pressure sensors30that transmit the pressure values.

The control unit10may determine that the collision occurs at a position adjacent to the pressure sensor30that first transmits the pressure value, among the plurality of pressure sensors30. The control unit10may determine where the collision occurs from a pressure value transmission point of time of the pressure sensor30that transmits the pressure value later among the plurality of pressure sensors30.

For example, when the plurality of pressure values are simultaneously received, the control unit10may determine that the collision occurs on the front of the vehicle. For example, when the control unit10receives the pressure value from the left pressure sensor30and thereafter, receives the pressure value from the right pressure sensor30, the control unit10may determine that the collision occurs at a position adjacent to the left pressure sensor.

The control unit10may determine that the collision occurs at a position adjacent to the pressure sensor that first transmits the pressure value. The control unit10may determine how far the collision occurs at a position from the pressure sensor30that first transmits the pressure value according to a time between a point of time of receiving the pressure value later and a point of time of receiving the pressure value first.

When the control unit10receives the pressure value from the pressure sensor30, the control unit10may control a signal width of the output signal based on the received pressure value. When the received pressure value is equal to or more than a first pressure value, the control unit10may increase a signal width variable. When the received pressure value is equal to or less than a second pressure value, the control unit10may decrease the signal width variable. When the pressure value output by the pressure sensor30has a magnitude between a first pressure value and a second pressure value, the control unit10may output an output signal having a signal width with a predetermined size, and when the pressure value is over a range between the first pressure value and the second pressure value, the control unit may increase or decrease the signal width of the output signal depending a degree that the value is over the range.

The control unit10may control the signal width in a hysteresis manner, but the present invention is not limited thereto. The control unit10may decide the output signal width based on the pressure value.

The control unit10outputs the pressure signal to determine whether the output value is the pedestrian. The control unit10may determine whether pressure over a threshold value is generated so as to determine whether the pressure value is the pedestrian by outputting the pressure signal. The control unit10may determine a pulse width from the pressure signal. The control unit10may determine whether the vehicle collides with the pedestrian by determining the relationship between the pulse width of the pressure signal and the pressure value.

The control unit10may receive the pressure value from at least one of the plurality of pressure sensors30. When the control unit10receives the pressure value from any one of the pressure sensors30disposed at both sides of the tube, respectively, the control unit10may determine whether the collision occurs by using another pressure sensor. For example, when the control unit10receives the pressure value from any one of the pressure sensors30disposed at both sides of the tube, respectively, the control unit10may determine whether another pressure sensor senses pressure which is equal to or more than the threshold value.

Although the control unit10receives the pressure value from any one pressure sensor, when another pressure sensor may not sense the pressure which is equal to or more than the threshold value, the control unit10may determine that the collision is not with a pedestrian.

When both pressure sensors sense the pressure, the control unit10may determine that the vehicle collides with the object. For example, when any one of both pressure sensors30senses the pressure, the control unit10may determine whether the other pressure sensor30senses the pressure.

When the control unit10receives the pressure values from the plurality of pressure sensors30, the control unit10may determine whether a pedestrian collision condition is satisfied.

The control unit10may calculate an accumulation value acquired by adding up pressure values for a predetermined time. The control unit10may determine whether the collision object is the pedestrian by considering the accumulation value and the pressure values.

The control unit10may determine the collision position by differences among points of time when the plurality of pressure sensors30senses the pressure. The control unit10sets a plurality of time ranges and may determine the collision position based on a time range to which the differences among the points of time when the plurality of pressure sensors30senses the pressure belong.

For example, the control unit10may set a first time range to a time range which is less than 2 ms, a second time range to a time range of 2 ms to 4 ms, and a third time range to a time range which is equal to or more than 4 ms. When the differences among the points of time of sensing the pressure is in the first time range, the control unit10may determine that the collision occurs at the center.

When the differences among the points of time of sensing the pressure is in the second time range, the control unit10may determine that the collision occurs at a portion between the center and the pressure sensor. When the differences among the points of time of sensing the pressure is in the third time range, the control unit10may determine that the collision occurs around the pressure sensor30. However, the time values are not limited to the exemplary times, and may vary depending on the size of the vehicle.

The control unit10may determine the speed of the vehicle at the point of time of receiving the pressure value. The control unit10may determine whether to perform an operation for protecting the pedestrian based on the speed when the vehicle collides. For example, when the pedestrian collides and a predetermined condition is satisfied, the control unit10expands an airbag or deploys a similar protective device on the front side of the vehicle to protect the pedestrian.

For example, when the speed upon the collision of the vehicle is within a predetermined range, the control unit10may perform the operation for protecting the pedestrian. For example, when the speed upon the collision of the vehicle is within the predetermined range, as the speed upon the collision of the vehicle increases, the control unit10may increase the pressure threshold value of performing the operation for protecting the pedestrian.

For example, when the speed upon the collision of the vehicle is in the range of 20 kph to 50 kph, the control unit10may perform the operation for protecting the pedestrian.

The control unit10may differentially apply the pressure threshold value of performing the operation for protecting the pedestrian depending on the collision position of the object. For example, when the speed upon the collision of the vehicle is equal to or more than approximately 30 kph, the control unit10increases the pressure value indicating that the object is the pedestrian to prevent erroneous expansion of the pedestrian protecting operation.

The pedestrian protection apparatus of a vehicle according to the exemplary embodiment of the present invention may further include the acceleration sensor40. The acceleration sensor40may determine an acceleration of the vehicle. The control unit10may reverify whether the pressure value sensed by the pressure sensor30is generated through the collision with the pedestrian depending on a change in acceleration of the vehicle, which is sensed by the acceleration sensor40.

The acceleration sensor40may be used to determine whether the front airbag is expanded when the vehicle collides head-on. The acceleration sensor40may be mounted on a front end module (FEM), a side member or a back beam, and the like. However, the acceleration sensor40may be installed at various positions, and as a result, the installation position is not limited to any one.

When the acceleration sensor40is disposed at the sides and a rear side of the vehicle, the control unit10may determine whether an acceleration accumulation amount (moving sum) of at least any one of left, right, and rear acceleration sensors of the vehicle is over a threshold value.

When the acceleration accumulation amount is not over a predetermined threshold value, the control unit10may prevent the operation for protecting the pedestrian.

The control unit10may determine an X-axis acceleration value sensed by an acceleration sensor in an airbag expansion logic (ACU). The control unit10may determine whether an accumulation amount of the X-axis acceleration value sensed by the acceleration sensor in the airbag expansion logic (ACU) is over the threshold value.

When the accumulation amount of the X-axis acceleration values sensed by the acceleration sensor is over the threshold value, the control unit10determines that the collision condition is a front collision condition such as a vehicle-to-vehicle collision or a fixed wall-to-vehicle collision to prevent the operation of the pedestrian protection apparatus.

Even when the control unit10determines that the vehicle collides with the object based on the pressure value received from the pressure sensor30, the control unit10does not immediately perform the operation for protecting the pedestrian and may determine whether the vehicle has collided with a pedestrian based on the acceleration value sensed by the acceleration sensor.

For example, when the control unit10determines that the acceleration sensed by the acceleration sensor40is changed due to the vehicle-to-vehicle collision or the collision with the object such as a wall, the control unit10may not perform the operation for protecting the pedestrian.

A memory20is connected to a processor of the control unit10, and may include a high-speed random access memory (RAM). The memory20may also include a non-volatile memory such as one or more magnetic disk storage devices, a flash memory device, or other non-volatile virtual memories, but the present invention is not limited thereto and may include a non-transitory computer readable storage medium.

For example, the memory20may include an electronically erasable and programmable read only memory (EEP-ROM), but the present invention is not limited thereto. In the EEP-ROM, information may be written in and erased by the control unit10. The EEP-ROM may be a memory device in which information stored therein is not erased but stored although power is turned off to stop supplying power.

A pedestrian collision position determining apparatus of a vehicle according to an exemplary embodiment may limitatively adopt the configurations and methods of the exemplary embodiments as described, but all or some of the respective exemplary embodiments may be selectively combined and configured so that the exemplary embodiments may be variously modified.

In an aspect, although an external tube is damaged by a dual-path structure tube installed in the pedestrian protection apparatus of a vehicle, protection of the pedestrian by sensing a variation in the amount of pressure of gas in an internal tube is improved based on more accurate determinations.

In an aspect, the pedestrian protection apparatus of a vehicle according to the exemplary embodiment of the present invention may accurately determine a collision position with an object based on differences among points of time when a plurality of pressure sensors sense a change in pressure, and then perform a pedestrian protection operation based thereon to protect the pedestrian.

In a further aspect, the pedestrian protection apparatus of a vehicle according to the exemplary embodiment of the present invention may additionally check whether the collision object is the pedestrian by using an acceleration sensor to prevent initiation of an unnecessary pedestrian protection operation.