Pressure induction type pedestrian protection detection device

Abstract

The utility model relates to a pressure induction type pedestrian protection detection device, and relates to the technical field of vehicle pedestrian protection. The system comprises a plurality of pressure sensing sheets, a pressure collector and a main controller which are arranged in a vehicle body, and the plurality of pressure sensing sheets are arranged in a front bumper in a distributed manner; the output ends of the multiple pressure sensing pieces are electrically connected to the input end of the pressure collector, and the pressure collector is in signal connection with the main controller. The method and the device have the effect of improving the capability of sensing and identifying the impact object under the condition of reducing the cost.

Description

Technical Field

[0001] This application relates to the technical field of vehicle and pedestrian protection, and in particular to a pressure-sensitive pedestrian protection detection device. Background Technology

[0002] The rapid development of automotive technologies in recent years has led to the widespread availability of higher-end features, allowing consumers to enjoy more functionality at more affordable prices. Airbag systems are no exception. To better protect pedestrians, the use of pedestrian airbags is becoming increasingly common. Currently, the mainstream type of pedestrian airbag is the hood airbag. Its principle involves sensors detecting the contact between a pedestrian and the bumper, and determining the impact intensity to trigger the hood airbag's deployment, causing the rear of the hood to pop up. During the time it takes for a pedestrian to roll over the hood and reach the windshield, the hood pops up, covering not only the bottom of the windshield but also potentially dangerous hard points such as the wiper shaft and hood brackets, effectively reducing the severity of injury.

[0003] Current airbag systems detect pedestrians using a combination of pressure sensors and accelerometers. The detection principle involves horizontally slotted energy-absorbing foam blocks inside the front bumper, with rubber tubes installed within these slots. A pressure sensor is mounted at each end of the rubber tube, and the sensors are sealed to both ends of the tube. When a pedestrian comes into contact with the front bumper, the pressure sensors detect changes in air pressure within the rubber tubes and transmit the pressure signal to the airbag main controller via the PSI5 bus. The main controller then uses algorithms and calibrated thresholds to determine whether to deploy the pedestrian airbag.

[0004] However, because the pressure change in the rubber hose during a pedestrian collision is small and the duration is short, it poses a challenge for algorithm recognition. Furthermore, relying solely on pressure recognition cannot accurately pinpoint the location of the pedestrian (or obstacle) impact, often resulting in the hood not popping up or popping up falsely in the event of a minor collision. Therefore, pedestrian protection detection typically adds 2-3 acceleration sensors for auxiliary judgment. Generally, two acceleration sensors are added to the left and right positions of the pressure sensors, and some systems also add an additional acceleration sensor in the middle of the rubber hose to prevent false identification.

[0005] In summary, the entire pedestrian protection detection system requires at least two barometric pressure sensors and two accelerometers. The large number of sensors required results in high costs, and even with the addition of accelerometers for auxiliary judgment, there is still a certain rate of false recognition. Utility Model Content

[0006] In order to improve the ability to detect and identify impacting objects while reducing costs, this application provides a pressure-sensitive pedestrian protection detection device.

[0007] The pressure-sensitive pedestrian protection detection device provided in this application adopts the following technical solution:

[0008] A pressure-sensitive pedestrian protection detection device includes a pressure sensor, a pressure collector, and a main controller, all disposed within a vehicle body. Multiple pressure sensors are distributed within the front bumper. The output terminals of the multiple pressure sensors are electrically connected to the input terminal of the pressure collector, and the pressure collector is signal-connected to the main controller.

[0009] By adopting the above technical solution, multiple pressure sensors are distributed and installed inside the front bumper, which can fully cover the front area of ​​the vehicle and ensure that the position of the pedestrian and the force of the collision can be accurately detected in the event of a collision. When the front bumper of the vehicle is hit, the pressure sensor at the impact position can output a pressure signal. By setting only one pressure acquisition unit, one or more pressure signals can be collected and output to the main controller, so that the main controller can determine whether the airbag needs to be deployed based on the position and number of pressure signals. Through the above structure, the number of sensors used can be reduced, thereby reducing costs.

[0010] Preferably, the pressure acquisition device includes a processing unit, an interface chip, and peripheral circuitry. The output terminals of the plurality of pressure sensing elements are respectively electrically connected to the plurality of input terminals of the processing unit. The processing unit is signal-connected to the main controller through the interface chip.

[0011] By adopting the above technical solution, the signals from multiple pressure sensors can be processed efficiently, and the interface chip can be used to communicate with the main controller to ensure the stability and real-time performance of signal transmission.

[0012] Preferably, the interface chip communicates bidirectionally with the main controller via current-tuned encoding / decoding.

[0013] By adopting the above technical solution, the interface chip communicates bidirectionally with the main controller through current-tuned encoding and decoding, which enhances the accuracy of data transmission and anti-interference capability, ensuring that the system can respond quickly and take corresponding protection measures.

[0014] Preferably, the pressure sensing element is fixed to the energy-absorbing foam or guide groove inside the front bumper by means of screwing, riveting, or snapping.

[0015] By adopting the above technical solution, the pressure sensor can be securely installed inside the front bumper, preventing it from shifting or falling off due to vibrations or other external factors during vehicle operation. This secure mounting improves the stability of the pressure sensor's operation, thereby ensuring the accuracy of pressure signal acquisition and further enhancing the reliability and safety of the pedestrian protection system.

[0016] Preferably, the pressure sensing element adopts a piezoelectric, piezoresistive, membrane switch, or electromagnetic signal conversion method.

[0017] By adopting the above technical solutions, and by selecting different signal conversion methods, the pressure sensing element can be flexibly selected according to specific application scenarios, thereby improving the system's adaptability and reliability.

[0018] Preferably, the density of the pressure sensing pads located in the front and side edge areas of the vehicle body is higher than the density of the pressure sensing pads located in the remaining areas.

[0019] By adopting the above technical solution, costs can be saved and excessive placement of sensor sheets in low-probability areas can be avoided.

[0020] In summary, this application includes at least one of the following beneficial technical effects:

[0021] 1. By distributing multiple pressure sensors within the front bumper and using a single pressure sensor to centrally process multiple pressure signals, the number of sensors required is reduced, thereby lowering costs. Simultaneously, this design provides comprehensive coverage of the front area of ​​the vehicle, ensuring accurate detection of pedestrian position and impact force in the event of a collision, thus improving sensing accuracy and system reliability.

[0022] 2. The pressure acquisition unit connects to the main controller via a processing unit and an interface chip. The interface chip uses current-tuned encoding and decoding for bidirectional communication with the main controller, enhancing the accuracy and anti-interference capability of data transmission. This design ensures the stability and real-time performance of signal transmission, enabling the system to respond quickly and take appropriate protective measures.

[0023] 3. Pressure sensing elements can adopt various signal conversion methods such as piezoelectric, piezoresistive, membrane switch, or electromagnetic, allowing the system to be flexibly selected according to specific application scenarios, thereby improving the system's adaptability and reliability. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the overall layout and connection of an embodiment of this application;

[0025] Figure 2 This is a schematic block diagram of an embodiment of this application;

[0026] Figure 3 This is a schematic diagram showing the connection between the computing unit and multiple pressure sensing plates in an embodiment of this application.

[0027] Reference numerals: 1. Pressure sensor; 2. Pressure acquisition unit; 21. Processing unit; 22. Interface chip; 3. Main controller; 4. Hardwire; 5. Bus. Detailed Implementation

[0028] The following is in conjunction with the appendix Figure 1-3 This application will be described in further detail.

[0029] This application discloses a pressure-sensitive pedestrian protection detection device.

[0030] Reference Figure 1 A pressure-sensitive pedestrian protection detection device includes a pressure sensor 1, a pressure collector 2, and a main controller 3, all installed inside a vehicle body. Multiple pressure sensors 1 are distributed within the front bumper. Each pressure sensor 1 is electrically connected to the pressure collector 2 via a hard wire 4. When subjected to force, the pressure sensor 1 outputs a pressure signal. The pressure sensor collects one or more pressure signals and outputs them to the main controller 3. The pressure collector 2 is electrically connected to the main controller 3 via a bus 5. The main controller 3 is used to trigger the airbag. The main controller 3, by acquiring the location and intensity of the pressure signal returned by the pressure collector 2, and combining this with algorithms and calibration parameters, determines the size of the contact area between the pedestrian and the vehicle and the impact intensity, deciding whether to deploy the hood airbag.

[0031] The pressure sensor 1 can employ piezoelectric, piezoresistive, membrane switch, or electromagnetic signal types to convert physical pressure into electrical signals. The type of pressure sensor 1 can be flexibly selected based on the specific application scenario. Multiple pressure sensors 1 are arranged into a strip-shaped sensing array along the length of the front bumper using a flexible PCB board or ribbon cable. The number of pressure sensors 1 within the sensing array and the distance between adjacent pressure sensors 1 can be adjusted according to actual needs. For example, multiple pressure sensors 1 can be evenly distributed along the length of the front bumper; or the density of pressure sensors 1 can be increased in the front and side edge areas of the vehicle, while the density is reduced in the remaining areas, thereby saving costs and avoiding excessive placement of sensors in low-probability areas.

[0032] Multiple pressure sensing elements 1 can be installed on the front contact surface of the energy-absorbing foam inside the front bumper or in the guide groove by means of screwing, riveting, or snapping, so as to avoid position displacement or falling off due to vibration or other external factors during vehicle operation, thereby ensuring the accuracy of pressure signal acquisition.

[0033] refer to Figure 2The pressure acquisition unit 2 includes a processing unit 21, an interface chip 22, and peripheral circuitry. The outputs of multiple pressure sensors 1 are electrically connected to multiple signal inputs of the processing unit 21 via hardwires 4. The processing unit 21 is connected to the main controller 3 via a bus 5 through the interface chip 22. The processing unit 21 must support at least multiple analog signal interfaces for acquiring electrical signals such as voltage, current, or resistance from the pressure sensors 1. This meets the data acquisition needs of the distributed pressure sensors 1 and avoids information loss or complex hardware expansion due to insufficient interfaces. The processing unit 21 also has fault detection functions for short circuits to power / ground, etc., of the pressure sensors 1, enabling timely monitoring and feedback of abnormal conditions when a short circuit occurs. The processing unit 21 also needs to perform position association based on the analog signal interfaces connected to different pressure sensors 1 to ensure a clear position-pressure correspondence when the signals are converted to digital signals and transmitted to the main controller 3.

[0034] The interface chip 22 achieves bidirectional communication by employing Manchester decoding or other current modulation encoding / decoding methods, thereby receiving control commands from the main controller 3 and transmitting the pressure signal output by the pressure sensor 1 to the main controller 3. The interface chip 22 also needs to have power supply capability, obtaining the power supply voltage through the bus 5 before supplying power to the processing unit 21. This eliminates the need for an additional power supply module, ensuring the normal operation of the processing unit 21 and reducing hardware complexity and cost.

[0035] refer to Figure 2 and Figure 3 Specifically, one end of each pressure sensor 1 is electrically connected to multiple ADC interfaces of the pressure acquisition unit 2 in a certain order via hard wires 4, so as to identify the output signals of the pressure sensor 1 located at different positions; the other end of the pressure sensor 1 is electrically connected to the ground terminal of the pressure acquisition unit 2.

[0036] The implementation principle of the pressure-sensitive pedestrian protection detection device in this application embodiment is as follows: using the pressure-sensitive pedestrian protection detection and identification scheme, it is not limited by the number of air pressure sensors, nor does it require the addition of acceleration sensors for auxiliary identification. It is convenient to install and the number of sensing points can be increased or decreased according to needs. Moreover, only one pressure collector 2 is required, and there are no restrictions on the installation position of the pressure collector 2 as long as it is connected to multiple effective points of pressure sensing plates 1, so as to reduce costs.

[0037] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A pressure-sensitive pedestrian protection detection device, characterized in that: The device includes a pressure sensor (1), a pressure collector (2), and a main controller (3) installed in the vehicle body. There are multiple pressure sensors (1), and the multiple pressure sensors (1) are distributed in the front bumper. The output terminals of the multiple pressure sensors (1) are electrically connected to the input terminal of the pressure collector (2), and the pressure collector (2) is signal connected to the main controller (3).

2. The pressure-sensitive pedestrian protection detection device according to claim 1, characterized in that: The pressure acquisition device (2) includes a processing unit (21), an interface chip (22) and peripheral circuits. The output terminals of the multiple pressure sensing elements (1) are respectively electrically connected to the multiple input terminals of the processing unit (21). The processing unit (21) is connected to the main controller (3) via the interface chip (22).

3. The pressure-sensitive pedestrian protection detection device according to claim 2, characterized in that: The interface chip (22) communicates bidirectionally with the main controller (3) through current debugging encoding and decoding.

4. The pressure-sensitive pedestrian protection detection device according to claim 1, characterized in that: The pressure sensing element (1) is fixed to the energy-absorbing foam or guide groove inside the front bumper by means of screwing, riveting or snapping.

5. The pressure-sensitive pedestrian protection detection device according to claim 1, characterized in that: The pressure sensing element (1) adopts a signal conversion form of piezoelectric, piezoresistive, membrane switch or electromagnetic.

6. The pressure-sensitive pedestrian protection detection device according to claim 1, characterized in that: The density of the pressure sensing pads (1) located in the front and side edge areas of the vehicle body is higher than the density of the pressure sensing pads (1) located in the remaining areas.

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