VEHICLE FRONT BUMPER, FRONT BUMPER SYSTEM AND VEHICLE

Abstract

A vehicle front fascia system includes an active hood system and a vehicle front fascia. The fascia includes an outer body structure providing a front surface of a vehicle equipped with the vehicle front fascia system, a compliant mechanism disposed within the outer body structure of the vehicle, and a sensor tube disposed within the jaw portion of the compliant mechanism. The compliant mechanism includes an arm portion and the jaw portion. The arm portion is movable relative to the impact beam to apply a compressive force to the jaw portion based on an impact to the outer body structure. The sensor tube generates a signal indicative of the impact to the outer body structure based on the detection of the compressive force at the jaw portion.

Description

INTRODUCTION

[0001] The present invention relates to a vehicle front fascia, a front fascia system, and a vehicle. The present disclosure generally relates to an active hood system for a vehicle.

[0002] The document DE 10 2013 018 323 A1, for example, discloses a vehicle front apron according to the preamble of claim 1, a front apron system according to the preamble of claim 9 and a vehicle according to the preamble of claim 10. The documents US 2020 / 0 276 952 A1, WO 2019 / 082 286 A1, WO 2019 / 082 287 A1, WO 2019 / 082 288 A1, WO 2019 / 082 289 A1 and JP 2019 - 172 154 A describe related vehicle front aprons.

[0003] Active hood systems are integrated into vehicles to protect pedestrians in the event of a low-speed impact. The purpose of an active hood system is to increase the amount of deformable space on a vehicle's hood and front fascia area to absorb the impact of a pedestrian contacting the front end of the vehicle. Larger vehicles, such as trucks and sport utility vehicles (SUVs), benefit from a front fascia large enough to create sufficient deformable space within the fascia, thereby reducing the need for an active hood system. However, smaller vehicles, such as sedans, sports cars, and coupes, are often designed with aggressive front fascia styling, generally resulting in a smaller front fascia that is low relative to the ground.Consequently, for these types of smaller vehicles, an active hood system may be integrated into the vehicle in an attempt to increase the amount of deformable space that provides protection for a pedestrian during a low-speed impact.

[0004] Active hood systems use sensors to detect an impact with an object near the front fascia and change characteristics of the hood when an impact is detected. For example, an active hood system may pivot the hood at a region near a hood pivot point in an attempt to create a deformable space in an area below the hood. Creating a deformable space allows the hood, as well as other components located near the front fascia, to move and / or deform more easily in response to an applied load. If the applied load is caused by a pedestrian making contact with the front fascia, the front fascia and associated components are allowed to move and / or deform more easily, gradually absorbing the energy associated with the applied load.

[0005] While conventional active hood systems mitigate the effects of a pedestrian contacting a vehicle's hood, such systems restrict the design of the front fascia to ensure that sensors associated with the active hood system can accurately and reliably detect an applied load. For example, active hood systems may require the front fascia to be constructed of a material with a specific hardness and / or may require the front fascia to have a specific shape or profile. Such requirements, while ensuring the proper function of the active hood system and its associated sensors, are often limiting from a design perspective.

[0006] It is an object of the invention to overcome the aforementioned disadvantages of the prior art. SUMMARY

[0007] The above object is achieved by a vehicle front apron according to claim 1, a front apron system according to claim 9 and a vehicle according to claim 10. Advantageous developments of the invention are specified in the subclaims.

[0008] One aspect of the disclosure provides a vehicle front fascia. The vehicle front fascia includes an outer body structure providing a front surface of a vehicle equipped with the vehicle front fascia, a compliant mechanism disposed within the outer body structure of the vehicle, and a sensor tube disposed within a claw portion of the compliant mechanism. The compliant mechanism includes an arm portion and the claw portion, the arm portion being movable relative to the impact beam to apply a compressive force to the claw portion based on an impact to the outer body structure. The sensor tube generates a signal indicative of the impact to the outer body structure based on the detection of the compressive force at the claw portion.

[0009] Implementations of the disclosure may include one or more of the following optional features. In some examples, an energy absorber is disposed between the outer body structure and the impact beam of the vehicle, the energy absorber being compressible between the outer body structure and the impact beam based on the impact at the outer body structure. In some further examples, the energy absorber comprises at least one selected from the group consisting of (i) a foam energy absorber and (ii) a plastic energy absorber. In some still further examples, the compliant mechanism is integrally formed with the energy absorber.

[0010] In some implementations, the compliant mechanism spans a length of the impact beam.

[0011] In some aspects, the compliant mechanism spans only a portion of a length of the sensor tube.

[0012] In some examples, the front surface of the vehicle is located at a height above a height of the impact beam of the vehicle.

[0013] In some implementations, the sensor tube is fixed relative to the impact beam.

[0014] In some aspects, the signal is transmitted to a front fascia system of the vehicle. In some further aspects, the front fascia system activates an active hood system of the vehicle based on the signal from the sensor tube.

[0015] Another aspect of the disclosure provides a front fascia system. The front fascia system includes an active hood system and a vehicle front fascia. The vehicle front fascia includes an outer body structure providing a front surface of the vehicle equipped with the vehicle front fascia, a compliant mechanism disposed within the outer body structure of the vehicle, and a sensor tube disposed within a jaw portion of the compliant mechanism. The compliant mechanism includes an arm portion and the jaw portion, wherein the arm portion is movable relative to the impact beam to apply a compressive force to the jaw portion based on an impact to the outer body structure.The sensor tube generates a signal indicating the impact on the outer body structure based on the detection of the compression force at the claw portion, the signal is transmitted to the front fascia system and activates the vehicle's active hood system.

[0016] Implementations of this aspect of the disclosure may include one or more of the following optional features. In some examples, an energy absorber is disposed between the outer body structure and the impact beam of the vehicle, wherein the energy absorber is compressible between the outer body structure and the impact beam based on the impact to the outer body structure.

[0017] In some implementations, the energy absorber comprises at least one selected from the group consisting of (i) a foam energy absorber and (ii) a plastic energy absorber. In some further implementations, the compliant mechanism is integrally formed with the energy absorber.

[0018] In some aspects, the front surface of the vehicle is disposed at a height above a height of the impact beam of the vehicle.

[0019] In some examples, the sensor tube is fixed relative to the impact beam.

[0020] Yet another aspect of the disclosure provides a vehicle. The vehicle includes a front fascia system. The front fascia system includes an active hood system and a vehicle front fascia. The vehicle front fascia includes an exterior body structure providing a front surface of a vehicle equipped with the vehicle front fascia, a compliant mechanism disposed within the exterior body structure of the vehicle, and a sensor tube disposed within a jaw portion of the compliant mechanism. The compliant mechanism includes an arm portion and the jaw portion, the arm portion being movable relative to the impact beam to apply a compressive force to the jaw portion based on an impact to the exterior body structure.The sensor tube generates a signal indicating the impact on the outer body structure based on the detection of the compression force at the claw portion, the signal is transmitted to the front fascia system and activates the vehicle's active hood system.

[0021] Implementations of this aspect of the disclosure may include one or more of the following optional features. In some examples, an energy absorber is disposed between the outer body structure and the impact beam of the vehicle, the energy absorber being compressible between the outer body structure and the impact beam based on the impact at the outer body structure, the energy absorber comprising at least one selected from the group consisting of (i) a foam energy absorber and (ii) a plastic energy absorber. In some further examples, the compliant mechanism is integrally formed with the energy absorber.

[0022] In some implementations, the front surface of the vehicle is located at a height above a height of the impact beam of the vehicle and the sensor tube is fixed relative to the impact beam. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings described here are for illustrative purposes only and show selected configurations; Fig. 1 a side view of a vehicle; Fig. 2 a cross-sectional view of a front apron of the vehicle of Fig. 1, showing a leading edge of the front apron; Fig. 3A is a perspective view of a compliant mechanism for an active hood system according to the principles of the present disclosure; Fig. 3B is a perspective view of the compliant mechanism of Fig. 3A, which is integrated into an energy absorption material of the active hood system; Fig. 4A is a diagram of the compliant mechanism of Fig. 3A in an unloaded state; Fig. 4B is a diagram of the compliant mechanism of Fig. 3A in a loaded state; Fig. 5A is a top view of an impact beam with a compliant mechanism disposed along a length of the entire impact beam; and Fig. 5B is a top view of an impact beam with multiple compliant mechanisms arranged at different locations on the impact beam.

[0024] Corresponding reference numerals indicate corresponding parts throughout the drawings. DETAILED DESCRIPTION

[0025] The terminology used herein is for the purpose of describing specific example configurations only and is not intended to be limiting. As used herein, the singular articles "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore indicate the presence of features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein should not be construed as necessarily requiring their performance in the particular order discussed or illustrated unless specifically identified as such an order of performance.Additional or alternative steps may be used.

[0026] When an element or layer is described as being "on," "engaging," "connected," "attached to," or "coupled to" another element or layer, it may be directly on, engaging, connected, attached to, or coupled to the other element or layer, or intermediate elements or layers may be present. Conversely, when an element is described as being "directly on," "directly engaging," "directly connected to," "directly attached to," or "directly coupled to" another element or layer, no intermediate elements or layers may be present. Other words used to describe the relationship between elements should be interpreted in a similar manner (e.g., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.).As used herein, the term “and / or” includes any combination of one or more of the related listed items.

[0027] The terms "first," "second," "third," etc., may be used herein to describe various elements, components, regions, layers, and / or sections. These elements, components, regions, layers, and / or sections should not be limited by these terms. These terms may only be used to distinguish one element, component, region, layer, or section from another region, layer, or section. Terms such as "first," "second," and other numerical terms do not imply a sequence or order unless clearly indicated by the context.Accordingly, a first element, component, region, layer, or section discussed below could be referred to as a second element, component, region, layer, or section without departing from the teachings of the example configurations.

[0028] In this application, including the definitions below, the term "module" may be replaced with the term "circuit." The term "module" may refer to, be a part of, or include an application-specific integrated circuit (ASIC); a digital, analog, or mixed analog / digital discrete circuit; a digital, analog, or mixed analog / digital integrated circuit; a combinational logic circuit; a field-programmable gate array (FPGA); a processor (shared, dedicated, or group) that executes code; memory (shared, dedicated, or group) that stores code executed by the processor; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system on a chip.

[0029] The term "code," as used above, may include software, firmware, and / or microcode, and may refer to programs, routines, functions, classes, data structures, and / or objects. The term "shared processor" includes a single processor that executes some or all of the code from multiple modules. The term "group processor" includes a processor that, in combination with additional processors, executes some or all of the code from one or more modules. The term "shared memory" includes a single memory that stores some or all of the code from multiple modules. The term "group memory" includes memory that, in combination with additional memory, stores some or all of the code from one or more modules. The term "memory" may be a subset of the term "computer-readable medium."The term "computer-readable medium" does not encompass transitory electrical and electromagnetic signals propagating through a medium and can therefore be considered tangible and non-transitory memory. Non-limiting examples of non-transitory memory include tangible computer-readable medium with non-volatile memory, magnetic memory, and optical memory.

[0030] The devices and methods described in this application may be implemented partially or entirely by one or more computer programs executed by one or more processors. The computer programs include processor-executable instructions stored on at least one non-transitory tangible computer-readable medium. The computer programs may also include and / or be based on stored data.

[0031] A software application (i.e., a software resource) may refer to computer software that causes a computing device to perform a task. In some examples, a software application may be referred to as an "application," "app," or "program." Example applications include, but are not limited to, system diagnostic applications, system management applications, system maintenance applications, word processing applications, spreadsheet applications, messaging applications, media streaming applications, social networking applications, and gaming applications.

[0032] Non-transitory memory may be physical devices used to store programs (e.g., sequences of instructions) or data (e.g., program state information) on a temporary or persistent basis for use by a computing device. Non-transitory memory may be volatile and / or non-volatile addressable semiconductor memory. Examples of non-volatile memory include, but are not limited to, flash memory and read-only memory (ROM) / programmable read-only memory (PROM) / erasable programmable read-only memory (EPROM) / electronically erasable programmable read-only memory (EEPROM) (e.g., typically used for firmware such as boot programs).Examples of volatile memory include, but are not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), phase change memory (PCM), and disk or tape.

[0033] These computer programs (also known as programs, software, software applications, or code) comprise machine instructions for a programmable processor and may be implemented in a high-level procedural and / or object-oriented programming language and / or assembly / machine language. As used herein, the terms "machine-readable medium" and "computer-readable medium" refer to any computer program product, non-transitory computer-readable medium, device, and / or apparatus (e.g., magnetic disks, optical disks, random access memory, programmable logic devices (PLDs)) used to deliver machine instructions and / or data to a programmable processor, including a machine-readable medium that receives machine instructions as a machine-readable signal.The term “machine-readable signal” refers to any signal used to convey machine instructions and / or data to a programmable processor.

[0034] Various implementations of the systems and techniques described herein may be embodied in digital electronic and / or optical circuitry, integrated circuitry, specially designed ASICs (Application Specific Integrated Circuits), computer hardware, computer firmware, computer software, and / or combinations thereof. These various implementations may include implementation in one or more computer programs executable or interpretable on a programmable system, including at least one programmable processor, which may be special-purpose or general-purpose, coupled to receive data and instructions from and transmit data and instructions to a memory system, at least one input device, and at least one output device.

[0035] The processes and logic described in this patent specification may be performed by one or more programmable processors, also referred to as data processing hardware, that execute one or more computer programs to perform functions by manipulating input data and generating output. The processes and logic may also be performed by special-purpose logic circuitry, such as an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). Processors suitable for executing a computer program include, by way of example, both general-purpose and special-purpose microprocessors and any one or more processors of any type of digital computer. Generally, a processor receives instructions and data from read-only memory or random-access memory, or both.The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to, one or more mass storage devices for storing data, such as magnetic, magneto-optical disks, or optical disks, or to receive data therefrom or transfer data to them, or both. However, a computer need not include such devices. Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, including, by way of example, semiconductor memory devices, such as EPROM, EEPROM, and flash memory devices; magnetic disks, such asInternal hard disks or removable disks; magneto-optical disks; and CD-ROM and DVD-ROM disks. The processor and memory may be supplemented by or integrated with special-purpose logic circuitry.

[0036] To provide interaction with a user, one or more aspects of the disclosure may be implemented on a computer having a display device, e.g., a CRT (cathode ray tube) monitor, LCD (liquid crystal display) monitor, or touch screen for displaying information to the user, and optionally a keyboard and a pointing device, e.g., a mouse or trackball, through which the user can provide input to the computer. Other types of devices may also be used to provide interaction with the user; for example, feedback provided to the user may be any form of sensory feedback, e.g., visual feedback, auditory feedback, or tactile feedback; and input from the user may be received in any form, including auditory, voice, or tactile input.Additionally, a computer may interact with a user by sending documents to and receiving documents from a device used by the user; for example, by sending web pages to a web browser on a client device of the user in response to requests received from the web browser.

[0037] A front fascia system is included as a feature in many vehicles that works to mitigate the damage and injury that can result from a front-end impact of the vehicle with a pedestrian. The damage and injury mitigation provided by the front fascia system applies to the vehicle itself, the vehicle's occupants, and the pedestrian struck by the vehicle. For vehicles such as sports cars and sedans with aggressive front-end styling, which generally includes angular fascias and low profiles, many front fascia systems include an active hood system. The active hood system works to increase the amount of deformable space provided at the front end of the vehicle during an impact with a pedestrian to increase the amount of energy absorbed by the vehicle and ideally reduce the extent of injury sustained by the pedestrian.When the active hood system is activated, the hood pivots upward at the rear end of the hood closest to the vehicle's windshield, creating additional deformable space at the front end of the vehicle. In doing so, the active hood system increases the amount of energy that can be absorbed by the vehicle during a pedestrian impact, mitigating the impact on the pedestrian.

[0038] In Fig. 1 and Fig. 2, a vehicle 10 is shown including a front portion 12 and a windshield 14 with a base 16. The front portion 12 comprises the entirety of the vehicle 10 disposed forward from the base 16 of the windshield 14. The front portion 12 includes a front fascia 18 defining a front end of the vehicle 10. The front fascia 18 includes an outer body 20 having an arcuate leading edge 22 defining a point that, in one configuration, may be disposed near a ground surface due to the overall shape of the front portion 12. The hood 24 includes a leading edge 26 disposed near the front fascia 18 of the vehicle 10 and a trailing edge 28 disposed near the windshield 14 of the vehicle 10.

[0039] In Fig. 2, the front portion 12 includes a cavity 30 disposed rearward of the outer body 20 of the front fascia 18. A first energy absorber 32 is disposed within the cavity 30 and is shaped to generally conform to the shape of the outer body 20. The first energy absorber 32 generally comprises a foam or foam-like material, however, it should be recognized that the composition of the first energy absorber 32 may be any material capable of absorbing an impact of an applied pressure. A second energy absorber 34 is also contained within the cavity 30 and is positioned rearward of the first energy absorber 32. The second energy absorber 34 generally comprises a plastic material, however, it should be recognized that the composition of the second energy absorber 34 may be any material capable of absorbing an impact of an applied pressure.Rearward of the second energy absorber 34, within the cavity 30, is an impact beam 36 made of a rigid material capable of both transferring a load from an impact on the front fascia 18 to other parts of the vehicle 10 and maintaining the structural integrity of the vehicle 10 during an impact.

[0040] With continued reference to Fig. 1 and Fig. 2 and with reference to Fig. 3A-4B, a compliant mechanism 38 is shown disposed within the cavity 30. The compliant mechanism 38 includes an arm portion 40 and a claw portion 42 extending from the arm portion 40. As shown in Fig. 3A, the arm portion 40 is positioned forward of the claw portion 42 within the cavity 30 such that the arm portion 40 is located closer to the apron 18 than the claw portion 42. The arm portion 40 is generally positioned at or near the first energy absorber 32, while the claw portion 42 is generally positioned between the first energy absorber 32 and the second energy absorber 34. Further, the arm portion 40 is positioned at a location directly or closely rearward of the leading edge 22 of the outer body 20 such that an impact at the leading edge 22 is applied to the arm portion 40. The compliant mechanism 38 comprises a relatively rigid material including a plurality of pivot points 44a, 44b that allow relative movement of the arm portion 40 and the claw portion 42 when a force is applied to the compliant mechanism 38 at the arm portion 40.The hinge points 44a, 44b include pivoting capabilities due to the material at the hinge points 44a, 44b having a reduced thickness compared to the rest of the compliant mechanism 38. As such, the hinge points 44a, 44b form movable joints that allow the material of the compliant mechanism 38—at the hinge points 44a, 44b—to deform either elastically or plastically. When a force is applied to the arm portion 40 and the hinge points 44a, 44b allow relative movement of the arm portion 40 and the claw portion 42, the claw portion 42 compresses, as shown in FIG. Fig. 4B shown.

[0041] Optionally, instead of the compliant mechanism 38 being an independent element disposed in the cavity 30, an alternative compliant mechanism 38a may be integrated into the first energy absorber 32, the second energy absorber 34, or both energy absorbers 32, 34 as a unitary piece, as shown in Fig. 3B. Forming the compliant mechanism 38a, the first energy absorber 32, and / or the second energy absorber 34 as a unitary piece can accommodate design constraints of the front portion 12 of the vehicle 10, as well as reduce the complexity of the components contained within the cavity 30. Whether the compliant mechanism 38 is an independent element or integrally formed with the first energy absorber 32 and / or the second energy absorber 34, the function of the claw portion 42, which is compressed when a force is applied to the arm portion 40, remains unchanged.

[0042] A sensor tube 46 may be disposed within the jaw portion 42 of the compliant mechanism 38 and may detect the applied pressure. In operation, when the sensor tube 46 detects an amount of applied pressure above a calibrated threshold, the sensor tube 46 sends a signal to activate an active hood system 100. The sensor tube 46 and the active hood system 100 may be in communication with processing hardware 200 and memory hardware 202, which may be components of a stand-alone controller or integrated into a controller of the vehicle 10, such as a body control module (BCM) (not shown). The processing hardware 200 and memory hardware 202 cooperate to control the operation of the active hood system 100 in response to information from the sensor tube 46.In particular, the memory hardware 202 may store instructions that, when executed by the processing hardware 200, cause the processing hardware 200 to perform operations, including activating the active hood system 100 when the sensor tube 46 detects an applied force above a predetermined threshold caused by the sensor tube 46 being compressed within the compliant mechanism 38. In particular, when the sensor tube 46 detects a force of a predetermined amount, the processing hardware 200 may activate the active hood system 100, which, in one configuration, causes the hood 24 to pivot near the rear edge 28. In doing so, the size of the cavity 30 is effectively increased, allowing the vehicle 10 to more easily absorb the energy associated with the applied force.As can be appreciated, allowing the vehicle 10 to absorb more energy associated with an applied load directs the energy away from a pedestrian when the applied load is caused by the pedestrian contacting the leading edge 22. As such, activating the active hood system 100 mitigates the effects of the pedestrian contacting the vehicle 10 at the leading edge 22 and protects the pedestrian.

[0043] With continued reference to Fig. 4A-4B, the sensor tube 46 is sized to fit within the jaw portion 42 and experience little to no applied pressure when the compliant mechanism 38 is in an uncompressed state 38b. However, when the compliant mechanism 38 is in a compressed state 38c, the jaw portion 42 compresses to an extent that applies pressure to the sensor tube 46 sufficient to trigger the active hood system 100.

[0044] With reference to Fig. 5A-5B, the location of the compliant mechanism 38 within the cavity 30 can vary without affecting its function. Although the sensor tube 46 can span a length L36 of the impact beam 36 that extends the entirety of the front fascia 18, multiple compliant mechanisms 38 can be positioned at various locations across the impact beam 36. The sensor tube 46 is routed through each jaw portion 42 of each compliant mechanism 38 included in this particular configuration. Alternatively, a single compliant mechanism 38 extending the entire length L36 of the impact beam 36 can be used. The compliant mechanism 38 in this configuration creates a continuous and uninterrupted arm portion 40 and jaw portion 42, with the sensor tube 46 disposed within the continuous jaw portion 42.Considerations regarding what configuration may be included in the vehicle 10 may include space and design constraints of the front fascia 18.

[0045] In operation and with renewed reference to Fig.2, the compliant mechanism 38 is disposed within the cavity 30 in a manner such that the arm portion 40 lies directly behind the leading edge 22 of the outer body 20. During an impact at the front fascia 18 of the vehicle 10, it is the leading edge 22 that receives the brunt of the impact since the leading edge 22 is the forwardmost portion of the vehicle 10. Due to varying exterior designs among different types of vehicles, and in particular, varying designs on the front fascia 18, the leading edge 22 may be angular as opposed to a flat, planar surface, providing little surface area at the leading edge 22. Furthermore, different designs on the front fascia 18 among different vehicles may position the leading edge 22 above or below the impact beam 36.However, the compliant mechanism 38 can be used to enable virtually any configuration of the front fascia 18 to be used in conjunction with the sensor tube 46 to enable the sensor tube 46 to accurately and reliably detect an impact. Indeed, provided that the arm portion 40 is positioned directly behind the leading edge 22 and the claw portion 42 is positioned forward of the impact beam 36 such that the sensor tube 46 is fixed relative to the impact beam 36, the processing hardware 200 of the vehicle 10 can successfully activate the active hood system 100 in response to the sensor tube 46 experiencing a force of a predetermined magnitude.

[0046] Continuing the operation of the disclosure, an example is described in which the vehicle 10 collides with a pedestrian at the front fascia 18. During the collision, a majority of the force from the pedestrian impact is applied at the leading edge 22 because the leading edge 22 is the forwardmost portion of the front fascia 18 and, consequently, of the vehicle 10. The force of the impact is partially absorbed by both the first energy absorber 32 and the second energy absorber 34, which are disposed within the cavity 30 in front of the rigid impact beam 36. However, because most of the force is applied to the leading edge 22, much of the force from the impact is transferred to the arm portion 40 of the compliant mechanism 38. The force at the arm portion 40 causes pivoting to occur at the pivot points 44a, 44b, which causes the jaw portion 42 of the compliant mechanism 38 to compress.As the claw portion 42 compresses, the sensor tube 46 disposed within the claw portion 42 experiences an increased amount of compression force. Once the sensor tube 46 experiences a compression force greater than the calibrated threshold, a signal is sent to the processing hardware 200, which in turn activates the active hood system 100. At this point, the active hood system 100 immediately intervenes, causing the hood 24 of the vehicle 10 to pivot at the leading edge 26, moving the trailing edge 28 upward. By pivoting the hood 24 at the leading edge 26, which consequently moves the hood 24 upward at the trailing edge 28, an increased amount of deformable space is created because pivoting the hood 24 creates an increased gap between the hood 24 and the rest of the vehicle 10.The more deformable space created by the vehicle 10 during an impact with a pedestrian, the greater the amount of force that can be absorbed by the vehicle 10 from the pedestrian. Creating additional deformable space is the primary purpose of the active hood system 100, as creating an increased amount of deformable space provides better protection for the pedestrian during an impact with the front fascia 18.

[0047] The inclusion of the compliant mechanism 38 within the cavity 30 allows for a significant increase in design flexibility on the outer body 20 of the vehicle 10. For example, the leading edge 22 does not need to be directly forward of the impact beam 36, as would be required for an active hood system that does not include a compliant mechanism 38. The leading edge 22 positioned above or below the impact beam 36 can still compress the sensor tube 46 sufficiently to activate the active hood system 100 during an impact at the leading edge 22 with the inclusion of the compliant mechanism 38.Because the force applied to the leading edge 22 during an impact is transferred to the arm portion 40, which compresses the claw portion 42 and applies sufficient pressure to the sensor tube 46 to activate the active hood system 100, the placement of the leading edge 22 on the front fascia 18 is not as restrictive compared to an active hood system without a compliant mechanism 38. Further, the leading edge 22 can be shaped to meet the design considerations of the front portion 12 of the vehicle 10 without requiring the leading edge 22 to be a flat surface. A leading edge that does not provide much surface area may not adequately transfer the force during an impact to a sensor tube in a vehicle that does not include a compliant mechanism.However, if the arm portion 40 of the compliant mechanism 38 is located directly behind the leading edge 22, the surface area of ​​the leading edge 22 can be reduced without sacrificing the amount of force received by the sensor tube 46 during an impact at the leading edge 22, thus increasing design flexibility.

[0048] Not only does the compliant mechanism 38 provide increased design flexibility on the outer body 20, but the components within the cavity 30 and the cavity 30 itself can be designed and arranged in a manner that does not require consideration of whether the sensor tube 46 is correctly positioned to compress it upon a force applied at the leading edge 22. The sensor tube 46 must be contained within the claw portion 42 of the compliant mechanism 38, and the arm portion 40 must be positioned rearward of the leading edge 22 to function correctly and activate the active hood system 100 upon an impact at the leading edge 22. Furthermore, the claw portion 42 must be positioned forward of the impact beam 36.Although the claw portion 42 is not in direct contact with the impact beam 36 because the second energy absorber 34 is disposed between the claw portion 42 and the impact beam 36, the rigidity of the impact beam 36 works to keep the claw portion 42 of the compliant mechanism 38 fixed to the leading edge 22 during an impact. If the claw portion 42 were not fixed, an impact on the arm portion 40 would not cause the pivot points 44a, 44b to pivot, but would rather cause the entire compliant mechanism 38 to simply translate as a result of the impact without any pivoting action.Fixing the claw portion 42 at a location forward of the rigid impact beam 36 helps enable the pivot points 44a, 44b to pivot on the arm portion 40 upon impact, thus compressing the claw portion 42 and creating a sufficient amount of compression force on the sensor tube 46 to activate the active hood system 100. Beyond these requirements, the components within the cavity 30 and the cavity 30 itself can be designed and positioned in a manner that does not require viewing of the sensor tube 46 to function properly during an impact event.

[0049] A number of implementations have been described. Nevertheless, it should be understood that various modifications may be made without departing from the spirit and scope of the disclosure.

[0050] The preceding description has been provided for explanatory and descriptive purposes.

Claims

[1] Vehicle front apron (18), comprising: an outer body structure (20) providing a front surface (22) of a vehicle (10) equipped with the vehicle front fascia (18); a compliant mechanism (38) disposed within the outer body structure (20) of the vehicle (10), the compliant mechanism (38) comprising an arm portion (40) and a claw portion (42) extending from the arm portion (40), the arm portion (40) being movable relative to an impact beam (36) to exert a compressive force on the claw portion (42) based on an impact on the outer body structure (20); and a sensor tube (46) disposed within the claw portion (42) of the compliant mechanism (38), the sensor tube (46) generating a signal indicative of the impact on the outer body structure (20) based on the detection of the compression force on the claw portion (42), characterized by , that the compliant mechanism (38) comprises a material including a first pivot point (44a) and a second pivot point (44b), wherein the first pivot point (44a) enables relative movement of the arm portion (40) and the claw portion (42) and the second pivot point (44b) enables compression of the claw portion (42) when a force is applied to the compliant mechanism (38) at the arm portion (40). [2] The vehicle front fascia (18) of claim 1, wherein an energy absorber (34) is disposed between the outer body structure (20) and the impact beam (36) of the vehicle (10), the energy absorber (34) being compressible between the outer body structure (20) and the impact beam (36) based on the impact on the outer body structure (20). [3] The vehicle front fascia (18) of claim 2, wherein the energy absorber (34) comprises at least one selected from the group consisting of (i) a foam energy absorber and (ii) a plastic energy absorber. [4] Vehicle front apron (18) according to claim 3, wherein the compliant mechanism (38) is formed integrally with the energy absorber (34). [5] The vehicle front fascia (18) of claim 1, wherein the compliant mechanism (38) spans a length of the impact beam (36) or only a portion of a length of the sensor tube (46). [6] The vehicle front fascia (18) of claim 1, wherein the front surface (22) of the vehicle (10) is disposed at a height above a height of the impact beam (36) of the vehicle (10). [7] Vehicle front apron (18) according to claim 1, wherein the sensor tube (46) is fixed relative to the impact beam (36). [8] The vehicle front fascia (18) of claim 1, wherein the signal from the sensor tube (46) is transmitted to a front fascia system of the vehicle (10), the front fascia system activating an active hood system (100) of the vehicle (10) based on the signal. [9] Front apron system, which includes: an active hood system (100); and a vehicle front apron (18) comprising: an outer body structure (20) providing a front surface (22) of a vehicle (10) equipped with the vehicle front fascia (18), the front surface (22) being disposed at a height above a height of an impact beam (36) of the vehicle; a compliant mechanism (38) disposed within the outer body structure (20) of the vehicle (10), the compliant mechanism (38) comprising an arm portion (40) and a claw portion (42) extending from the arm portion (40), the arm portion (40) being movable relative to the impact beam (36) to exert a compressive force on the claw portion (42) based on an impact on the outer body structure (20), an energy absorber (34) disposed between the outer body structure (20) and the impact beam (36) of the vehicle (10), the energy absorber (34) comprising at least one selected from the group consisting of (i) a foam energy absorber and (ii) a plastic energy absorber, the energy absorber (34) being disposed between the outer body structure (20) and the impact beam (36) based on the impact on the outer body structure (20), and a sensor tube (46) disposed within the claw portion (42) of the compliant mechanism (38), the sensor tube (46) generating a signal indicative of the impact on the outer body structure (20) based on the detection of the compression force on the claw portion (42), the signal being transmitted to the front fascia system and activating the active hood system (100) of the vehicle (10), the sensor tube (46) being fixed relative to the impact beam (36), characterized by , that the compliant mechanism (38) comprises a material including a first pivot point (44a) and a second pivot point (44b), wherein the first pivot point (44a) enables relative movement of the arm portion (40) and the claw portion (42) and the second pivot point (44b) enables compression of the claw portion (42) when a force is applied to the compliant mechanism (38) at the arm portion (40). [10] Vehicle (10) comprising: a front apron system that includes: an active hood system; and a vehicle front apron (18) comprising: an outer body structure (20) providing a front surface (22) of a vehicle (10) equipped with the vehicle front fascia (18), the front surface (22) being disposed at a height above a height of an impact beam (36) of the vehicle (10); a compliant mechanism (38) disposed within the outer body structure (20) of the vehicle (10), the compliant mechanism (38) comprising an arm portion (40) and a claw portion (42) extending from the arm portion (40), the arm portion (40) being movable relative to the impact beam (36) to exert a compressive force on the claw portion (42) based on an impact on the outer body structure (20), an energy absorber (34) disposed between the outer body structure (20) and the impact beam (36) of the vehicle (10), the energy absorber (34) comprising at least one selected from the group consisting of (i) a foam energy absorber and (ii) a plastic energy absorber, the energy absorber (34) being disposed between the outer body structure (20) and the impact beam (36) based on the impact on the outer body structure (20), and a sensor tube (46) disposed within the jaw portion (46) of the compliant mechanism (38), wherein the sensor tube (46) generates a signal indicative of the impact on the outer body structure (20) based on the detection of the compression force on the jaw portion (42), the signal being transmitted to the front fascia system and activating the active hood system (100) of the vehicle (10), wherein the sensor tube (46) is fixed relative to the impact beam (36) characterized by , that the compliant mechanism (38) comprises a material including a first pivot point (44a) and a second pivot point (44b), wherein the first pivot point (44a) enables relative movement of the arm portion (40) and the claw portion (42) and the second pivot point (44b) enables compression of the claw portion (42) when a force is applied to the compliant mechanism (38) at the arm portion (40).

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