External recognition aid device

Abstract

The present invention provides an external recognition assistance device that ensures sufficient visibility through the windshield even during heavy rainfall or snowfall. [Solution] The external recognition assistance device comprises a front hood 6 that constitutes the vehicle body 2 in front of the windshield 5, a connecting mechanism 26 provided at the front of the front hood 6 that connects the front hood 6 to the vehicle body frame, a pair of left and right height adjustment mechanisms 30 provided at the rear of the front hood 6 that can adjust the height of the rear of the front hood 6, and a visibility control unit 50. The visibility control unit 50 controls the operation of the pair of left and right height adjustment mechanisms 30 so that the height of the rear of the front hood 6 is higher than the reference position during rainfall.

Description

Technical Field

[0001] The present invention relates to an external recognition assistance device that assists in recognizing the outside of a vehicle from the inside of the windshield.

Background Art

[0002] Conventionally, a driving environment recognition device has been put into practical use in which an imaging unit such as a camera is provided inside the front windshield of a vehicle to recognize the driving environment outside the vehicle. The driving environment information recognized by such a driving environment recognition device is used for various driving support controls.

[0003] In order to ensure a view through the front windshield, water droplets or the like adhering to the front windshield during rainfall or snowfall are removed by wiping using a wiper or the like. As a technique for improving the wiping performance of the wiper, for example, the technique disclosed in Patent Document 1 is known. Patent Document 1 discloses a technique in which a plate-like member extending in the longitudinal direction of the vehicle is provided in a cowl portion between the front windshield and the front hood, and washer fluid sprayed from a washer nozzle is carried by the traveling wind and guided to an area within the angle of view of an imaging means.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, for example, during rainfall or snowfall with a large amount of precipitation, it may be difficult to sufficiently secure a view only by wiping the front windshield using a wiper. In such a case, it may be difficult to recognize the driving environment in front of the vehicle, and there may be a risk that it becomes difficult to continue driving support control or the like.

[0006] The present invention aims to provide an external recognition assistance device that can ensure sufficient visibility through the windshield even during heavy rainfall or snowfall. [Means for solving the problem]

[0007] An external vehicle recognition assistance device according to one aspect of the present invention comprises a front hood that constitutes the vehicle body in front of the windshield, a connecting mechanism provided at the front of the front hood and connecting the front hood to the vehicle body frame, at least one height adjustment mechanism provided at the rear of the front hood and capable of adjusting the height of the rear of the front hood, and a processor, wherein the processor controls the operation of the at least one height adjustment mechanism so that the height of the rear of the front hood becomes higher than a reference position during rainfall. [Effects of the Invention]

[0008] According to the vehicle exterior recognition assistance device of the present invention, sufficient visibility through the windshield can be ensured even during heavy rainfall or snowfall. [Brief explanation of the drawing]

[0009] [Figure 1] Schematic diagram of the external vehicle recognition assistance device [Figure 2] Front view of the vehicle [Figure 3] Side view of the vehicle [Figure 4] Cross-sectional view of the main parts of the front hood and height adjustment mechanism. [Figure 5] Cross-sectional view of the front hood and key parts of the height adjustment mechanism when the height adjustment mechanism is in operation. [Figure 6] Cross-sectional view of the main parts of the front hood and height adjustment mechanism when the front hood is open. [Figure 7] Front view of the vehicle when the height adjustment mechanism is in operation. [Figure 8] Side view of the vehicle when the height adjustment mechanism is in operation. [Figure 9] Plan view showing the airflow layers formed when the height adjustment mechanism is in operation. [Figure 10] Flowchart showing the external vehicle recognition assistance control routine [Figure 11] Chart showing the relationship between precipitation and wiper operation status. [Figure 12] A modified example, showing the front view of the vehicle when the height adjustment mechanism is in operation. [Figure 13] A modified example, a plan view showing the airflow layers formed when the height adjustment mechanism is in operation. [Modes for carrying out the invention]

[0010] The embodiments of the present invention will be described below with reference to the drawings. The drawings relate to one embodiment of the present invention, where Figure 1 is a schematic configuration diagram of the external recognition assistance device, Figure 2 is a front view of the vehicle, Figure 3 is a side view of the vehicle, and Figure 4 is a cross-sectional view of the main parts of the front hood and height adjustment mechanism.

[0011] As shown in Figures 1 to 3, a vehicle (own vehicle) 1 such as an automobile has a windshield 5 and a front hood 6 at the front of the vehicle body 2.

[0012] The windshield 5 is positioned at a predetermined angle of elevation from the front to the rear of the vehicle body 2. This windshield 5 separates the front of the passenger compartment from the outside of the vehicle. A camera unit 10 is installed inside the passenger compartment, which is inside the windshield 5. A wiper device 11 is also installed near the front end of the windshield 5.

[0013] The camera unit 10 is fixed, for example, at the upper center of the front part inside the vehicle cabin of the vehicle 1. In the present embodiment, the camera unit 10 has a stereo camera composed of a main camera 10a and a sub-camera 10b. The main camera 10a and the sub-camera 10b image the driving environment in the traveling direction (mainly forward) of the vehicle 1 through the windshield 5 respectively. Image processing such as stereo matching is performed on the driving environment images captured by the main camera 10a and the sub-camera 10b using an image processing unit (not shown) and the like. Thereby, the camera unit 10 recognizes various objects and the like existing around the road on which the vehicle 1 travels as driving environment information. Here, the objects recognized by the camera unit 10 include, for example, other vehicles (preceding vehicles, side-by-side vehicles, etc.) traveling in front of or to the side of the vehicle 1, pedestrians walking in front or trying to cross in front, bicycles, motorcycles and other moving objects such as three-dimensional objects, signal displays (lighting color, blinking state, arrow direction, etc.), road signs, stop lines, lane boundary lines and other road markings. Further, the objects include buildings adjacent to the road, walls, sound insulation walls, guardrails and the like.

[0014] The wiper device 11 has a wiper link 15, a wiper motor 16, and a wiper blade 17. The wiper link 15 is constituted by, for example, a parallel type link mechanism. The wiper link 15 converts the rotational motion of the wiper motor 16 into a reciprocating motion and transmits it to the wiper blade 17. By this reciprocating motion, the wiper blade 17 wipes the windshield 5. Here, the wiping range of the windshield 5 by the wiper blade 17 includes the regions of the respective viewing angles of the main camera 10a and the sub-camera 10b.

[0015] The front hood 6 constitutes the vehicle body 2 in front of the windshield 5. This front hood 6 covers the upper part of a space such as an engine room formed in the front part of the vehicle body 2. As shown in FIGS. 1 and 4, a striker 21 and a pair of hinge arms 22 are respectively fixed to the back surface of the front hood 6.

[0016] The striker 21 is fixed to the approximate center of the front portion of the front hood 6. The striker 21 is engageable with a locking mechanism 25 provided at the front portion of the vehicle body 2. The locking mechanism 25 is fixed to a radiator core support 20 or the like that constitutes the vehicle body skeleton. By engaging with such a locking mechanism 25, the striker 21 connects the front portion of the front hood 6 to the vehicle body skeleton. That is, the striker 21 and the locking mechanism 25 constitute a connecting mechanism 26 for connecting the approximate center of the front portion of the front hood 6 to the vehicle body skeleton.

[0017] As shown in FIG. 1, each hinge arm 22 is fixed to both end portions in the vehicle width direction (both left and right end portions) at the rear portion of the front hood 6. Here, each hinge arm 22 connects the rear portion of the front hood 6 to the vehicle body skeleton by the same connection configuration. Therefore, in the following description, unless necessary, only one of the pair of left and right connection structures will be described.

[0018] The hinge arm 22 is connected to the hinge base 27 in a rotatable state. The hinge base 27 is supported by the vehicle body 2 via a height adjustment mechanism 30 described later. Thus, the hinge arm 22 and the hinge base 27 constitute a hood hinge 28 for connecting the front hood 6 to the vehicle body skeleton in a swingable manner.

[0019] The height adjustment mechanism 30 includes a housing 31, a pedestal 32, a gear mechanism 33, and a lifting motor 34 as an actuator.

[0020] As shown in FIG. 4, the housing 31 is provided, for example, on a front upper side frame 40 that constitutes the vehicle body skeleton. This housing 31 has, for example, a concave shape with an open upper end and a predetermined depth downward.

[0021] The base 32 is positioned inside the housing 31 so as to be movable in the vertical direction of the housing 31. The hinge base 27 of the hood hinge 28 is fixed to this base 32. As a result, the hood hinge 28 is connected to the front upper side frame 40 so as to be movable in the vertical direction.

[0022] The gear mechanism 33 includes a rack gear 33a and a pinion gear 33b. The rack gear 33a extends downward from, for example, the back surface of the base 32. The pinion gear 33b is connected to the drive shaft of the lifting motor 34 in a state of meshing with the rack gear 33a.

[0023] The lifting motor 34 is fixed, for example, to the bottom of the housing 31. The lifting motor 34 transmits driving force to the pinion gear 33b. This causes the lifting motor 34 to change the meshing position between the pinion gear 33b and the rack gear 33a, thereby moving the base 32 in the vertical direction.

[0024] In such a configuration, for example, as shown in Figure 1, the wiper motor 16 and the pair of lifting motors 34 are operated and controlled by the visibility control unit 50. Here, all or part of the visibility control unit 50 is composed of a processor including hardware. The processor is composed of a well-known configuration and peripheral devices, such as a central processing unit (CPU), RAM (Random Access Memory), ROM (Read Only Memory), non-volatile memory, non-volatile storage, and non-transitory computer readable medium. ROM, non-volatile memory, non-volatile storage, etc., pre-store software programs executed by the CPU, data tables, and other fixed data.

[0025] The visibility control unit 50 is connected to, for example, a water droplet sensor 51, a communication device 52, a vehicle speed sensor 53, and a wiper switch 54.

[0026] The water droplet sensor 51 includes, for example, an infrared LED (not shown) and a photodiode. The water droplet sensor 51 measures the amount of infrared light reflected from the windshield 5 by the photodiode. Here, infrared light irradiated onto the part of the windshield 5 where water droplets are attached does not reflect off the surface of the windshield 5 but passes through the water droplets. Therefore, the more water droplets attached to the surface of the windshield 5, the less reflected light is incident on the photodiode. Based on this principle, the water droplet sensor 51 detects the amount of water droplets attached to the windshield 5 (i.e., the amount of rainfall).

[0027] The communication device 52 can communicate wirelessly with weather infrastructure and other devices outside the vehicle. Through this wireless communication, the communication device 52 obtains weather information for the area in which the vehicle 1 is currently traveling. The weather information obtained by the communication device 52 includes information on precipitation.

[0028] The wiper switch 54 is a switch for operating the wiper blade 17 at multiple speeds in response to operation by a driver or the like. In this embodiment, the wiper switch 54 can select three speeds for the operation speed of the wiper blade 17, for example, consisting of the first stage (low wiper speed), the second stage (medium wiper speed), and the third stage (high wiper speed).

[0029] When the visibility control unit 50 detects precipitation such as rain or snow while the vehicle 1 is in motion, it activates the lifting motor 34 to adjust the height of the rear of the front hood 6. Specifically, when information regarding the amount of precipitation is input from the water droplet sensor 51 and the communication device 52, the visibility control unit 50 uses the lifting motor 34 to raise the rear of the front hood 6 to a position higher than the reference position. Here, the reference position for the height of the rear of the front hood 6 is the height at which the front hood 6 completely covers the upper part of the space such as the engine compartment (see Figures 2-4). When the rear of the front hood 6 is raised to a position higher than the reference position, the front hood 6 tilts with the coupling mechanism 26 as the pivot point (see Figures 5, 7, and 8). As a result, the slope of the front hood 6 increases compared to when the rear of the front hood 6 is at the reference position. This increase in the slope of the front hood 6 causes the front hood 6 to guide the airflow upward. As a result, the front hood 6 forms a film of airflow caused by the driving wind at a position away from the windshield 5 (see the dashed line in Figure 8 and the dotted area W in Figure 9). This film of airflow repels rain, snow, etc., and reduces the amount of rain, snow, etc. that reaches the windshield 5 (see Figure 8).

[0030] Here, the visibility control unit 50 controls the height of the rear of the front hood 6 variably according to, for example, the vehicle speed and the amount of rainfall. Specifically, the visibility control unit 50 controls the operation of the lifting motor 34 so that the rear of the front hood 6 rises as the vehicle speed increases. This is to prevent the airflow film from approaching the windshield 5 as the wind speed of the driving air increases. Furthermore, the visibility control unit 50 controls the operation of the lifting motor 34 so that the rear of the front hood 6 rises as the amount of rainfall increases. This is to deflect rain, snow, etc., as far away from the windshield 5 as possible, thereby reducing the probability that rain, snow, etc., will reach the windshield 5. The relationship between vehicle speed, rainfall, and the height of the rear of the front hood 6 is mapped in advance based on experiments, for example, and stored in ROM or non-volatile memory.

[0031] Furthermore, when the vehicle 1 stops, the visibility control unit 50 controls the lifting motor 34 to return the height of the rear of the front hood 6 to the reference position. This is to ensure that the front hood 6 can be opened and closed (see Figure 6).

[0032] Furthermore, the visibility control unit 50 operates the wiper motor 16 when the wiper switch 54 is operated by the driver or the like. In this case, the visibility control unit 50 controls the operation of the wiper motor 16 at a rotational speed corresponding to the operating speed of the wiper blade 17 (any of the 1st to 3rd speeds) selected by the wiper switch 54. As a result, the wiper blade 17 wipes the windshield 5 at the operating speed selected by the wiper switch 54.

[0033] Furthermore, even when the wiper switch 54 is not operated, the visibility control unit 50 automatically activates the wiper motor 16 when it detects precipitation such as rain and snow while the vehicle 1 is in motion. In this case, the visibility control unit 50 controls the operation of the wiper motor 16 at a rotation speed corresponding to the amount of precipitation. That is, the visibility control unit 50 controls the operation of the wiper motor 16 so that the rotation speed increases in stages as the amount of precipitation increases. As a result, the wiper blade 17 wipes the windshield 5 at the operating speed set in the wiper switch 54 (one of the speeds from the 1st to 3rd stages). However, if the height of the rear of the front hood 6 is raised, the visibility control unit 50 lowers the operating speed of the wiper blade 17 by one stage compared to the operating speed corresponding to the amount of precipitation (see, for example, Figure 11). This is because the airflow film formed by the front hood 6 can suppress the amount of rain, snow, etc. that reaches the windshield 5.

[0034] Next, the external vehicle recognition assistance control performed in the visibility control unit 50 will be explained according to the flowchart of the external vehicle recognition assistance control routine shown in Figure 10. This routine is executed repeatedly at set intervals.

[0035] When the routine starts, the visibility control unit 50 checks in step S101 whether or not the vehicle 1 is in motion.

[0036] Then, if it is determined in step S101 that the vehicle 1 is stopped (step S101: NO), the visibility control unit 50 proceeds to step S110.

[0037] On the other hand, if in step S101 it is determined that the vehicle 1 is in motion (step S101: YES), the visibility control unit 50 proceeds to step S102.

[0038] In step S102, the visibility control unit 50 acquires information regarding the amount of rainfall in the area where the vehicle 1 is traveling from the water droplet sensor 51 and the communication device 52, etc.

[0039] In the following step S103, the visibility control unit 50 checks whether the operating conditions for the external vehicle recognition assistance function are met. This determination is made, for example, based on the amount of rainfall in the area where the vehicle 1 is traveling. In other words, the operating conditions for the external vehicle recognition assistance function include the amount of rainfall being equal to or greater than a set amount. This is because if the amount of rainfall is less than the set amount, there is a high probability that sufficient visibility can be secured without activating the external vehicle recognition assistance function.

[0040] Then, if it is determined in step S103 that the operating conditions are met (step S103: YES), the visibility control unit 50 proceeds to step S105.

[0041] On the other hand, if it is determined in step S103 that the operating conditions are not met (step S103: NO), the visibility control unit 50 proceeds to step S104.

[0042] In step S104, the visibility control unit 50 checks, for example, whether or not there is a visibility problem with the windshield 5 based on an image captured by a stereo camera.

[0043] Then, in step S104, if it is determined that there is no visibility impairment in the windshield 5 (step S104: NO), the visibility control unit 50 proceeds to step S110.

[0044] On the other hand, if in step S104 it is determined that there is poor visibility through the windshield 5 (step S104: YES), the visibility control unit 50 proceeds to step S105.

[0045] When the system proceeds from step S103 or step S104 to step S105, the visibility control unit 50 refers to a pre-set map or the like and calculates the height of the rear of the front hood 6 relative to the reference position.

[0046] In the following step S106, the visibility control unit 50 performs similar operational control on the left and right lifting motors 34 to adjust the height of the rear of the front hood 6 using the height adjustment mechanism 30.

[0047] In the following step S107, the visibility control unit 50 checks whether the wiper switch 54 has been operated by the driver or the like.

[0048] Then, if it is determined in step S107 that an operation has been performed on the wiper switch 54 (step S107: YES), the visibility control unit 50 proceeds to step S109.

[0049] On the other hand, if it is determined in step S107 that no operation has been performed on the wiper switch 54 (step S107: NO), the visibility control unit 50 proceeds to step S108.

[0050] In step S108, the visibility control unit 50 performs automatic control of the wiper device 11 and then exits the routine. That is, the visibility control unit 50 calculates the rotation speed of the wiper motor 16 according to the amount of rainfall. In this case, the visibility control unit 50 calculates a value for the rotation speed of the wiper motor 16 that increases in stages as the amount of rainfall increases. Furthermore, while the height control of the rear of the front hood 6 is being performed, the visibility control unit 50 calculates a value for the rotation speed of the wiper motor 16 that is one step slower than the value corresponding to the amount of rainfall. Then, the visibility control unit 50 operates the wiper motor 16 based on the calculated rotation speed.

[0051] Furthermore, when the process proceeds from step S101 or step S104 to step S110, the visibility control unit 50 controls the lifting motor 34 to return the height of the rear of the front hood 6 to the reference position.

[0052] In the following step S111, the visibility control unit 50 checks whether the wiper device 11 is being automatically controlled.

[0053] Then, if it is determined in step S111 that the wiper device 11 is being automatically controlled (step S111: YES), the visibility control unit 50 proceeds to step S112.

[0054] In step S112, the visibility control unit 50 automatically stops the wiper device 11 and then exits the routine. That is, the visibility control unit 50 automatically stops the wiper motor 16.

[0055] On the other hand, if it is determined in step S111 that the wiper device 11 is not under automatic control (step S111: NO), the visibility control unit 50 proceeds to step S109.

[0056] When the process proceeds from step S107 or from step S111 to step S109, the visibility control unit 50 controls the drive of the wiper device 11 according to the operation status of the wiper switch 54 by the driver or the like, and then exits the routine.

[0057] According to this embodiment, the external recognition assistance device comprises a front hood 6 that constitutes the vehicle body 2 in front of the windshield 5, a connecting mechanism 26 provided at the front of the front hood 6 and connecting the front hood 6 to the vehicle body frame, a pair of left and right height adjustment mechanisms 30 provided at the rear of the front hood 6 and capable of adjusting the height of the rear of the front hood 6, and a visibility control unit 50. The visibility control unit 50 controls the operation of the pair of left and right height adjustment mechanisms 30 so that the height of the rear of the front hood 6 is higher than the reference position during rainfall. This ensures sufficient visibility through the windshield 5 even during heavy rainfall or snowfall. Therefore, even during rainfall or snowfall, the camera unit 10 can appropriately recognize driving environment information, and various driving assistance controls can be continued without interruption.

[0058] In the above-described embodiment, an example was explained in which the same operational control was applied to a pair of left and right lifting motors 34 to control the height of the rear of the front hood 6 to be equal on both sides. However, when the vehicle 1 is traveling on a curve, or when the vehicle 1 is traveling under a crosswind, etc., it is also possible to set different control amounts for the pair of left and right lifting motors 34. This makes it possible to set the height of the rear of the front hood 6 to be asymmetrical on the left and right sides, as shown in Figures 12 and 13. With such control, it is possible to form an airflow film in the area including the fields of view of the main camera 10a and the sub-camera 10b, in response to changes in wind direction and changes in the direction of the wind while traveling on a curve.

[0059] The inventions described in the above embodiments are not limited to those forms, and various modifications can be made in the implementation stage without departing from the gist of the invention. Furthermore, the above embodiments include inventions at various stages, and various inventions can be extracted by appropriate combinations of the multiple constituent elements disclosed.

[0060] For example, if the problem described can be solved and the effects described can be obtained even if some of the constituent elements shown in the above form are removed, then the configuration with the removed constituent elements can be extracted as an invention.

[0061] Furthermore, while the above-described embodiment described a configuration for applying the external vehicle recognition assistance device to assist in recognizing the external driving environment using a stereo camera, the device is not limited to this configuration. For example, the external vehicle recognition assistance device can also be applied to assist in recognizing the external driving environment using a monocular camera, and to assist in recognizing the external driving environment by the driver. [Explanation of Symbols]

[0062] 1 ... Vehicle (own vehicle) 2… Vehicle body 5… Windshield 6… Front hood 10 ... Camera unit 10a ... Main camera 10b ... Sub-camera 11… Wiper device 15… Wiper Link 16… Wiper motor 17… Wiper blade 20… Radiator core support 21... Striker 22… Hinge arm 25… Locking mechanism 26 … Connection mechanism 27… Hinge base 28… Hood hinge 30 … Adjustment mechanism 31… Housing 32… Pedestal 33… Gear mechanism 33a ... Rack gear 33b… Pinion gear 34… Lifting motor 40… Front upper side frame 50… Vision control unit 51… Water droplet sensor 52… Communications device 53… Vehicle speed sensor 54… Wiper switch

Claims

1. The front hood, which forms part of the vehicle body in front of the windshield, A connecting mechanism provided at the front of the front hood, which connects the front hood to the vehicle body frame, The rear of the front hood is provided with at least one height adjustment mechanism capable of adjusting the height of the rear of the front hood, Processor and Equipped with, The external vehicle recognition assistance device is characterized in that the processor controls the operation of at least one height adjustment mechanism so that the height of the rear of the front hood becomes higher than the reference position during rainfall.

2. The vehicle exterior recognition assistance device according to claim 1, characterized in that the at least one height adjustment mechanism is provided at both ends of the front hood in the vehicle width direction.

3. The vehicle exterior recognition assistance device according to claim 2, characterized in that the processor is capable of controlling the at least one height adjustment mechanism so that both ends of the front hood in the vehicle width direction are at different heights.

4. The external vehicle recognition assistance device according to claim 1, characterized in that the processor controls the operation of at least one height adjustment mechanism so that the height of the rear of the front hood increases as the amount of rainfall increases during the rain.

5. The vehicle exterior recognition assistance device according to claim 1, characterized in that the processor controls the operating speed of the wipers to be slower when the height of the rear of the front hood is higher than the reference position than when the height of the rear of the front hood is at the reference position.

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