Step detection device and step detection method

Abstract

To arrange an irradiator and an imager used for detecting a step integrally or at near positions.SOLUTION: A step detection device 101 comprises: an emission control unit 11 that emits diffusion light of a reference emission pattern which can irradiate a peripheral road surface with a predetermined reference irradiation pattern when the peripheral road surface of a vehicle 31 is a flat reference road surface from an irradiator 21 mounted on the vehicle 31 toward the peripheral road surface; and a step detection unit 12 that extracts a real irradiation pattern applied to the peripheral road surface by the diffusion light of the reference emission pattern from a captured image of the peripheral road surface photographed by an imager 22 mounted on the vehicle 31, and detects a step on the peripheral road surface through comparison of the real irradiation pattern and the reference irradiation pattern in size.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a technology for detecting a step on a road surface. [Background technology]

[0002] Patent Document 1 describes a road surface condition estimation device that detects deformation of an irradiation pattern on a road surface by capturing an image of a pattern emitted from an illuminator with an image capturer, and estimates a road surface gradient.

[0003] However, in the road surface condition estimation device of Patent Document 1, because parallel light is emitted from the illuminator, if the axis of the incident light from the illuminator to the detection object and the axis of the reflected light from the detection object to the imager are the same or close to each other, deformation of the irradiation pattern cannot be detected with high accuracy. Therefore, it is necessary to place the illuminator and the imager at a certain distance or more, and there is a problem that a realizable configuration requires space. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2013-205196 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure has been made to solve the above problems, and has an object to dispose an illuminator and an imager used for detecting a step integrally or in close proximity to each other. [Means for solving the problem]

[0006] The step detection device disclosed herein includes an emission control unit that causes an illuminator mounted on the vehicle to emit diffuse light of a reference emission pattern, which is capable of irradiating a predetermined reference irradiation pattern onto the surrounding road surface when the surrounding road surface is a flat reference road surface, toward the surrounding road surface, and a step detection unit that extracts an actual irradiation pattern irradiated onto the surrounding road surface by the diffuse light of the reference emission pattern from an image of the surrounding road surface captured by an imager mounted on the vehicle, and detects steps in the surrounding road surface based on a comparison of the size of the actual irradiation pattern and the reference irradiation pattern. Effect of the Invention

[0007] According to the step detection device of the present disclosure, a step is detected based on the size of the pattern of diffused light irradiated from the illuminator onto the surrounding road surface. Therefore, the illuminator and the imager can be disposed integrally or in close proximity to each other. [Brief description of the drawings]

[0008] [Figure 1] 1 is a configuration diagram of a step detection device according to a first embodiment. [Diagram 2] FIG. 2 is a configuration diagram of an irradiator according to the first embodiment. [Diagram 3] FIG. 13 is a diagram showing how diffuse light is irradiated onto a road surface from an illuminator. [Figure 4] 1A and 1B are diagrams illustrating differences in irradiation patterns on a reference road surface, a curb, and a groove. [Diagram 5] FIG. 13 is a diagram showing a display example of a warning notifier. [Figure 6] 4 is a flowchart showing the operation of the step detection device according to the first embodiment. [Figure 7] FIG. 13 is a diagram showing the configuration of an irradiator of a comparative example having a mesh-type emission pattern. [Figure 8] FIG. 11 is a configuration diagram of a step detection device according to a second embodiment. [Figure 9] FIG. 13 is a diagram showing a travel route when the steering angle is small. [Figure 10] FIG. 13 is a diagram showing a travel route when a steering angle is large. [Figure 11]It is a diagram showing the irradiation range when the rudder angle is small. [Figure 12] It is a diagram showing the irradiation range when the rudder angle is large. [Figure 13] It is a diagram showing the irradiation range when the rudder angle is small and some of the light sources are turned off. [Figure 14] It is a diagram showing the irradiation range when the rudder angle is large and some of the light sources are turned off. [Figure 15] It is a diagram showing the change in the reference irradiation range according to the distance between the light source and the slit. [Figure 16] It is a diagram showing the case where the irradiation range of some of the light sources is expanded and the number of lit light sources is reduced. [Figure 17] It is a flowchart showing the emission control process by the step detection device according to Embodiment 2. [Figure 18] It is a diagram showing the hardware configuration of the step detection device. [Figure 19] It is a diagram showing the hardware configuration of the step detection device.

Embodiments for Carrying Out the Invention

[0009] <A. Embodiment 1> <A-1. Configuration> FIG. 1 is a configuration diagram of a step detection device 101 according to Embodiment 1. The step detection device 101 uses an irradiator 21 and an imager 22 mounted on a vehicle to detect a step on the road surface around the vehicle, and outputs the detection result to a warning notifier 23 and a vehicle controller 24.

[0010] The illuminator 21 is mounted on a vehicle and emits diffused light toward a road surface around the vehicle. FIG. 2 is a configuration diagram of the illuminator 21. The light source 211 may be one, or may be multiple as in the example of FIG. 2. Four light sources 211 are shown in FIG. 2. The four light sources 211 are, for example, LEDs (Light-Emitting Diodes), and are arranged side by side so that their respective illumination ranges do not overlap. A plate-shaped light-shielding member 212 is provided parallel to the arrangement direction of the light sources 211. The light-shielding member 212 is provided with four slits 212S that correspond one-to-one to the four light sources 211. The emitted light from each light source 211 passes through the slits 212S and is emitted from the illuminator 21 as one emission pattern.

[0011] A control unit 213 is connected to each light source 211, and the on / off of each light source 211 is controlled by the control unit 213. In addition, a light shielding wall 214 is provided between adjacent light sources 211 so that the emitted light from each light source 211 does not interfere with each other.

[0012] 2, the slit 212S is circular, but may be of another shape. However, the area of ​​the slit 212S is set to be larger than the emission area of ​​the light source 211 so that the light passing through the slit 212S becomes diffused light.

[0013] 2, a configuration in which diffuse light is irradiated using the light blocking member 212 has been described, but this is merely one example of the configuration of the irradiator 21. As long as it is possible to irradiate diffuse light, other configurations may be used for the irradiator 21. For example, a prism may be provided as another optical system instead of the light blocking member 212.

[0014] The imager 22 captures an image of the road surface around the vehicle illuminated by the illuminator 21, and outputs the captured image to the step detection device 101. The imager 22 may be configured in the same housing as the illuminator 21, or may be disposed in a nearby position. The illuminator 21 and the imager 22 may be provided, for example, in one central location or one each on the left and right sides of the front of the vehicle, near door mirrors or bumpers on the left and right sides of the vehicle, or in one central location or one each on the left and right sides of the rear of the vehicle, or may be provided in a plurality of these locations.

[0015] Next, there will be described the configuration of the step detection device 101. As shown in Fig. 1, the step detection device 101 is configured to include an emission control unit 11, a step detection unit 12, and an output control unit 13.

[0016] The emission control unit 11 controls the illuminator 21 to emit diffused light of a reference emission pattern to the road surface around the vehicle. The reference emission pattern is an emission pattern that can irradiate a predetermined reference irradiation pattern onto a reference road surface around the vehicle when the reference road surface around the vehicle is the reference road surface. The reference road surface is a flat road surface without irregularities. In this embodiment, the range of the surrounding road surface irradiated by the illuminator 21 is predetermined, for example, a range of 10 m ahead of the vehicle. The emission control unit 11 is aware of information on the installation position of the illuminator 21, and based on this, controls the illuminator 21 so that the predetermined range of the surrounding road surface is irradiated.

[0017] Under the control of the emission control unit 11, the control unit 213 of the illuminator 21 switches each light source 211 on and off uniformly so that the illuminator 21 irradiates the reference emission pattern.

[0018] The step detection unit 12 analyzes the image of the road surface around the vehicle captured by the imager 22, and extracts the pattern actually irradiated on the surrounding road surface by the diffused light of the irradiator 21. If the surrounding road surface is a flat reference road surface without any irregularities, the reference irradiation pattern should be irradiated on the surrounding road surface. However, if the surrounding road surface has irregularities such as curbs or grooves, the pattern actually irradiated differs from the reference irradiation pattern. Therefore, the pattern actually irradiated on the surrounding road surface is called the actual irradiation pattern.

[0019] Furthermore, the step detection unit 12 compares the actual irradiation pattern with the reference irradiation pattern, and detects steps on the surrounding road surface based on a comparison of the sizes of the two.

[0020] FIG. 3 shows a state in which diffused light is irradiated from the irradiator 21 provided on the vehicle 31 onto the surrounding road surface. In the example of FIG. 3, the imager 22 is configured integrally with the irradiator 21. The configuration of the irradiator 21 is as illustrated in FIG. 2. The diffused light emitted from the four light sources 211 through the slits 212S of the light blocking member 212 is defined as diffused light 361, 362, 363, 364, respectively. When the diffused light 361, 362, 363, 364 is irradiated onto the reference road surface 34 without the curbstone 33 or the groove 35, the reference irradiation patterns A1, A2, A3, A4 by the diffused light 361, 362, 363, 364 are obtained on the reference road surface 34. When the curbstone 33 is present on the surrounding road surface, the irradiation patterns B1, B2 by the diffused light 361, 362 are obtained on the curbstone 33. When a groove 35 is present in the surrounding road surface, irradiation patterns C3 and C4 are obtained at the bottom surface of the groove 35 by diffused lights 363 and 364.

[0021] FIG. 4 shows each irradiation pattern described in FIG. 3. When a curbstone 33 is present, the irradiation patterns B1 and B2 by the diffused lights 361 and 362 are smaller than the reference irradiation patterns A1 and A2. Therefore, when the actual irradiation pattern is smaller than the reference irradiation pattern, the step detection unit 12 can determine that a convex portion such as a curbstone 33 exists relative to the reference road surface 34 at the irradiation position of the actual irradiation pattern. The higher the curbstone 33, the smaller the size of the irradiation patterns A1 and A2. Therefore, the step detection unit 12 can also calculate the height of the convex portion from the ratio of the size of the actual irradiation pattern to the reference irradiation pattern.

[0022] When a groove 35 is present, the irradiation patterns C3 and C4 by the diffused lights 363 and 364 are larger than the reference irradiation patterns A3 and A4. Therefore, when the actual irradiation pattern is larger than the reference irradiation pattern, the step detection unit 12 can determine that a recess such as a groove 35 exists in the irradiation position of the actual irradiation pattern relative to the reference road surface 34. The deeper the groove 35 is, the larger the size of the irradiation patterns C3 and C4 will be. Therefore, the step detection unit 12 can also calculate the depth of the recess from the ratio of the size of the actual irradiation pattern to the reference irradiation pattern.

[0023] In the example of Figure 3, the illuminator 21 and the imager 22 are configured as an integral unit, but even if these are located at separate positions, the step detection unit 12 can detect a step using the method described above.

[0024] The output control unit 13 acquires the step detection result from the step detection unit 12, and when it is determined that the detected step will impede the traveling of the vehicle, it causes the warning notifier 23 to issue a warning to warn the vehicle occupants of the presence of the step. For example, when the height of the step is equal to or greater than a predetermined threshold value such as 30 cm, the output control unit 13 may determine that the step will impede the traveling of the vehicle. The height of the step is the height of the convex part or the depth of the concave part. The warning by the warning notifier 23 is issued by display or sound or both. That is, the warning notifier 23 is equipped with a display or a speaker or both.

[0025] FIG. 5 shows an example of a warning display by the warning notifier 23. In the example of FIG. 5, the warning notifier 23 performs a warning display using the display area 54 between the speedometer 52 and the tachometer 53 of the instrument panel 51. In the display area 54, a vehicle icon indicating the vehicle, a route icon 56 indicating the traveling route of the vehicle, and a step icon 57 indicating a step are displayed. By this display, the driver of the vehicle can recognize that there is a step in the left front of the vehicle and drive to avoid the step.

[0026] Further, when the output control unit 13 determines that the detected step hinders the travel of the vehicle, the output control unit 13 may cause the vehicle controller 24 to control the vehicle so as to avoid the step. In this case, the vehicle 31 is an autonomous vehicle capable of being controlled by the vehicle controller 24 to perform at least one of steering, acceleration, or deceleration. The vehicle controller 24 receives an instruction from the output control unit 13 and controls, for example, the steering of the vehicle so as to avoid a step or brakes the vehicle so as to stop in front of the step.

[0027] <A-2. Operation> FIG. 6 is a flowchart showing the operation of the step detection device 101 according to the first embodiment. Hereinafter, the operation of the step detection device 101 will be described along the flowchart of FIG. 6. The flowchart of FIG. 6 starts with the start of the vehicle travel and is repeatedly performed at any time, such as at a fixed cycle, during the travel.

[0028] First, in step S101, the emission control unit 11 causes the irradiator 21 to emit diffused light of the reference emission pattern onto the surrounding road surface of the vehicle.

[0029] Next, in step S102, the imager 22 captures an image of the surrounding road surface irradiated by the irradiator 21, and the step detection unit 12 analyzes the captured image to extract the actual emission pattern. The step detection unit 12 compares the actual emission pattern with the reference emission pattern and determines the presence or absence of a step from the difference in the sizes of both, and if there is a step, determines its height.

[0030] Thereafter, in step S103, the output control unit 13 determines whether there is a step that hinders running. For example, when the height of the step detected in step S102 is equal to or greater than the threshold value, step S103 becomes Yes, and the process of the step detection device 101 proceeds to step S104.

[0031] In step S104, the output control unit 13 causes the warning notifier 23 to notify the driver of the vehicle that there is a step on the vehicle's path. Note that the output control unit 13 may perform vehicle control to forcibly avoid the step in addition to the warning notification in this step.

[0032] If no step is detected in step S102, or if the height of the step detected in step S102 is less than the threshold value, step S103 becomes No, and the process of the step detection device 101 ends.

[0033] <A-3. Comparative Example> In FIGS. 2 to 4, the emission pattern by the irradiator 21 has been described as circular. The emission pattern by the irradiator 21 is not limited to circular, but it is preferably circular. Hereinafter, the case where the emission pattern by the irradiator 21 is a mesh type will be described as a comparative example, and the effects of the circular emission pattern will be explained.

[0034] FIG. 7 shows the configuration of the irradiator 21 of a comparative example that emits diffused light of a mesh-type pattern as the emission pattern. In the comparative example, the slit 212S1 provided in the light shielding member 212 is not circular but mesh type. In this case, since the distance to the light source 211 varies depending on the part of the slit 212S1, the diffusion ratio on the road surface fluctuates depending on which diffused light passes through the slit 212S1. Therefore, diffused light with an easy size determination cannot be generated, leading to a decrease in determination accuracy. In order to avoid this, it is necessary to arrange a large number of light sources according to the mesh shape of the slit 212S1, which increases the circuit complexity, causes the configuration of the irradiator 21 to become larger, and requires more installation space.

[0035] On the other hand, when the slit 212S is circular as shown in FIG. 2, since the distance between the light source 211 and the slit 212S can be kept constant, the diffusion ratio on the peripheral road surface can be kept constant throughout the entire irradiation pattern. Therefore, a small irradiator 21 can irradiate diffused light with an easily determinable size.

[0036] <A-4. Effect> The step detection device 101 according to Embodiment 1 includes an emission control unit 11 that emits diffused light of a reference emission pattern capable of irradiating a reference irradiation pattern predetermined on the peripheral road surface when the peripheral road surface of the vehicle 31 is a flat reference road surface, from the irradiator 21 mounted on the vehicle 31 toward the peripheral road surface, and a step detection unit 12 that extracts an actual irradiation pattern irradiated on the peripheral road surface by the diffused light of the reference emission pattern from a captured image of the peripheral road surface captured by the imager 22 mounted on the vehicle 31, and detects a step on the peripheral road surface based on a comparison of the sizes of the actual irradiation pattern and the reference irradiation pattern. Since the step detection device 101 detects a step using the irradiation pattern of diffused light in this way, the irradiator 21 and the imager 22 can be arranged integrally or at a short distance.

[0037] <B. Embodiment 2> <B-1. Configuration> FIG. 8 is a diagram showing the configuration of a step detection device 102 according to Embodiment 2. The step detection device 102 includes a path estimation unit 14 in addition to the configuration of the step detection device 101 according to Embodiment 1.

[0038] The path estimation unit 14 acquires the current steering angle of the vehicle from the steering 25 of the vehicle, and estimates a traveling path that the vehicle is likely to pass through in the future based on the steering angle. The traveling path of the vehicle estimated by the path estimation unit 14 is referred to as an estimated path. The estimated path may be estimated within the range where diffused light is irradiated from the irradiator 21. For example, when the irradiator 21 irradiates diffused light on the peripheral road surface 10 m ahead of the vehicle, the path estimation unit 14 may also estimate the traveling path up to 10 m ahead of the vehicle.

[0039] The emission control unit 11 acquires an estimated route of the vehicle from the route estimation unit 14, and sets the irradiation range of the diffused light by the irradiator 21 so as to include the estimated route.

[0040] 9 and 10 show the difference in the travel path due to the difference in the steering angle. FIG. 9 shows the travel path when the steering angle is smaller than that of FIG. 10, and FIG. 10 shows the travel path when the steering angle is larger than that of FIG. 9. In these figures, the travel path T1 of the vehicle 31 when the vehicle 31 travels from the current position X1 to the future position X2 is shown by a matte finish, the travel path T2 of the front wheels is shown by a solid line, and the travel path T3 of the rear wheels is shown by a dashed line. For example, when the vehicle 31 is slowly traveling at a speed of 10 km / h, the future position X2 is a position where the vehicle 31 will arrive in about 4 seconds. From a comparison between FIG. 9 and FIG. 10, it can be seen that the travel path T1 of the vehicle 31 is wider when the steering angle is large compared to when the steering angle is small, and the difference between the travel path T2 of the front wheels and the travel path T3 of the rear wheels is larger.

[0041] If the direction of the diffused light from the illuminator 21 is constant, the step detection range of the step detection device 102, i.e., the range of the diffused light from the illuminator 21, needs to be set wide in advance so as to include the entire travel path T1 of the vehicle 31 at any steering angle. The wide preset illumination range is shown in Figs. 11 and 12. In these figures, the illuminator 21 has eight light sources with different illumination ranges. The illumination ranges D1-D8 of the diffused light from the eight light sources are arranged without gaps, and an illumination range 61 of the illuminator 21 is obtained by these. The illumination range 61 is set so as to illuminate the travel path T1 without omissions at any steering angle, so that unnecessary ranges are generated depending on the actual steering angle. In the example of Fig. 11, the illumination ranges D3-D7 can cover the travel path T1 of the vehicle 31, and the illumination ranges D1, D2, and D8 are unnecessary. Also in the example of FIG. 12, the travel route T1 of the vehicle 31 can be covered by the illumination range D3-D8, and the illumination ranges D1 and D2 are not necessary.

[0042] Therefore, the emission control unit 11 decides to turn off the light sources 211 whose predetermined illumination ranges do not overlap the travel route T1, and instructs the illuminator 21. The control unit 213 of the illuminator 21 turns off some of the light sources 211 in accordance with the instruction from the emission control unit 11. As a result, the illumination range of the diffuse light from the illuminator 21 becomes as shown in Figs. 13 and 14. In this way, the power consumption of the illuminator 21 is reduced by turning off the light sources 211 whose illumination ranges include a range that is not necessary for detecting a step on the travel route T1 of the vehicle 31.

[0043] The emission control unit 11 may instruct the illuminator 21 to change the irradiation range of each light source in addition to turning on or off each light source of the illuminator 21. The control unit 213 of the illuminator 21 performs control to expand or reduce the irradiation range of each light source according to the instruction of the emission control unit 11.

[0044] FIG. 15 shows a method for expanding or reducing the irradiation range of the irradiator 21. The irradiation range on the reference road surface 42 without a step by the diffused light emitted from one light source 211 is set as the reference irradiation range R1, and the irradiation range on the step 41 is set as the step irradiation range R2. If the distance between the light source 211 and the slit 212S is shortened, the reference irradiation range R1 and the step irradiation range R2 become larger, and if the distance between the light source 211 and the slit 212S is lengthened, the reference irradiation range R1 and the step irradiation range R2 become smaller. In this way, the irradiation range of the diffused light can be expanded or reduced by adjusting the distance between the light source 211 and the slit 212S. Note that the step 41 in FIG. 15 is a convex step, but the same applies to a concave step.

[0045] If the distance between the light source 211 and the slit 212S is shortened to increase the irradiation range, the difference between the reference irradiation range R1 and the step irradiation range R2 increases, improving the calculation accuracy of the step height or depth, in other words, improving the accuracy of judging whether or not there is a step. Also, if the distance between the light source 211 and the slit 212S is lengthened to reduce the irradiation range, the resolution of the detectable step, i.e., the detection accuracy of the size such as the width of the step, improves.

[0046] Therefore, as shown in FIG. 16, in addition to turning off the light sources corresponding to the irradiation ranges D1 and D2 that do not overlap with the traveling route T1 of the vehicle 31, the emission control unit 11 turns off the light sources corresponding to the irradiation ranges D3, D5, and D7, and may expand the irradiation ranges D4, D6, and D8. Thereby, a wide range can be covered with a small number of light sources, and the detection accuracy regarding the presence or absence of steps in the irradiation ranges D4, D6, and D8 is improved. When a step is detected in the irradiation ranges D4, D6, and D8, the emission control unit 11 reduces the irradiation ranges D4, D6, and D8 and turns on the light sources corresponding to the irradiation ranges D5 and D7. Thereby, the detection accuracy of the width of the detected step is improved.

[0047] <B-2. Operation> FIG. 17 is a flowchart showing the emission control process by the step detection device 102. In advance, in the emission control unit 11, the irradiation range of the irradiator 21 is determined so as to cover the traveling routes of the vehicle for all possible steering angles at a point separated from the vehicle by a predetermined distance such as 10 m in front of the vehicle.

[0048] In step S201, the route estimation unit 14 acquires the steering angle information of the steering 25. Next, in step S202, the route estimation unit 14 estimates the traveling route of the vehicle based on the steering angle information of the steering 25. Thereafter, in step S203, the emission control unit 11 sets at least a part of the light sources 211 whose irradiation ranges do not overlap with the traveling route to be off. In this step, the emission control unit 11 may expand the irradiation ranges of some of the light sources 211 among the plurality of light sources 211 whose irradiation ranges overlap with the traveling route and set the remaining light sources 211 to be off.

[0049] <B-3. Effect> The step detection device 102 according to the second embodiment includes a route estimation unit 14 that estimates a traveling route planned for the vehicle to travel on the surrounding road surface based on the steering angle of the steering 25 of the vehicle 31 in addition to the configuration of the step detection device 101. The emission control unit 11 causes the irradiator 21 to emit the diffused light of the reference emission pattern toward the traveling route. Therefore, according to the step detection device 102, a step on the traveling route can be detected.

[0050] The plurality of light sources 211 irradiate the peripheral road surface in front of or behind the vehicle 31 at a predetermined distance from the vehicle, and when all of the plurality of light sources 211 are on, the irradiation range of the plurality of light sources 211 is at a position at a predetermined distance from the vehicle 31 in the forward or backward direction of the vehicle 31. It includes all the driving routes assumed when the steering is made variable from the maximum steering angle in one direction to the maximum steering angle in the other direction. The emission control unit 11 controls at least one of the plurality of light sources 211 to be turned off according to the driving route estimated by the route estimation unit 14. Thereby, by turning off the light source 211 whose irradiation range does not overlap with the driving route, it is possible to suppress unnecessary irradiation for step detection.

[0051] The emission control unit 11 controls the distance between at least one of the plurality of light sources 211 and the optical system according to the driving route estimated by the route estimation unit 14. Thereby, the irradiation range of each light source 211 can be expanded or reduced, and the detection accuracy of the step and the measurement accuracy of the width of the step can be improved.

[0052] <C. Hardware Configuration> In the above-described step detection devices 101 and 102, the emission control unit 11, the step detection unit 12, the output control unit 13, and the route estimation unit 14 are realized by the processing circuit 81 shown in FIG. 18. That is, the processing circuit 81 includes an emission control unit 11, a step detection unit 12, an output control unit 13, and a route estimation unit 14 (hereinafter, referred to as "emission control unit 11 etc."). A dedicated hardware may be applied to the processing circuit 81, or a processor that executes a program stored in a memory may be applied. The processor is, for example, a central processing unit, a processing device, an arithmetic device, a microprocessor, a microcomputer, a DSP (Digital Signal Processor), or the like.

[0053] When the processing circuit 81 is a dedicated hardware, the processing circuit 81 corresponds to, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination of these. Each function of the parts such as the emission control unit 11 may be realized by a plurality of processing circuits 81, or the functions of each part may be realized by a single processing circuit.

[0054] When the processing circuit 81 is a processor, the functions of the emission control unit 11 and the like are realized by a combination of software, etc. (software, firmware, or software and firmware). The software, etc. is written as a program and stored in a memory. As shown in FIG. 19, a processor 82 applied to the processing circuit 81 realizes the functions of each unit by reading and executing a program stored in a memory 83. That is, the step detection devices 101, 102 include a memory 83 for storing a program that, when executed by the processing circuit 81, results in the processing of the emission control unit 11 and the like. In other words, this program can be said to cause a computer to execute the procedure or method of the emission control unit 11 and the like. Here, the memory 83 may be, for example, a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), or an EEPROM (Electrically Erasable Programmable Read Only Memory), a HDD (Hard Disk Drive), a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD (Digital Versatile Disk) and its drive device, or any storage medium to be used in the future.

[0055] The above describes a configuration in which the functions of the emission control unit 11 and the like are realized either by hardware or software, etc. However, the present invention is not limited to this, and a configuration in which a part of the emission control unit 11 and the like is realized by dedicated hardware and another part is realized by software, etc. For example, the function of the emission control unit 11 can be realized by a processing circuit as dedicated hardware, and the other functions can be realized by the processing circuit 81 as the processor 82 reading and executing a program stored in the memory 83.

[0056] As described above, the processing circuitry can realize the above-mentioned functions by hardware, software, or a combination of these.

[0057] The step detection device 102 is typically an in-vehicle device, but can also be applied to a system constructed by appropriately combining a PND (Portable Navigation Device), a communication terminal (e.g., a mobile terminal such as a mobile phone, a smartphone, or a tablet), the functions of applications installed thereon, and a server. In this case, the functions or components of the step detection devices 101, 102 described above may be distributed and disposed in each device that constructs the system, or may be centralized and disposed in one of the devices. The step detection devices 101, 102 may include at least one of the illuminator 21 and the imager 22, which have been separate in the above description.

[0058] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments without departing from the scope of the claims.

[0059] Various aspects of the present disclosure are summarized below as appendices.

[0060] (Appendix 1) an emission control unit that emits, from an illuminator mounted on the vehicle, diffused light of a reference emission pattern that can irradiate a predetermined reference irradiation pattern onto the surrounding road surface when the surrounding road surface of the vehicle is a flat reference road surface; A step detection unit extracts an actual irradiation pattern irradiated onto the surrounding road surface by the diffused light of the reference emission pattern from a photographed image of the surrounding road surface photographed by an imager mounted on the vehicle, and detects a step on the surrounding road surface based on a comparison of the size of the actual irradiation pattern and the size of the reference irradiation pattern. Step detection device.

[0061] (Appendix 2) and an output control unit that causes a warning notifier mounted on the vehicle to issue a visual or audio warning that the step exists based on the step detection result. 2. A step detection device as described in appendix 1.

[0062] (Appendix 3) The vehicle is an autonomous vehicle whose steering, acceleration, or deceleration can be controlled by a vehicle controller; An output control unit that causes the vehicle controller to control the vehicle so as to avoid the detected step. 2. The step detection device according to claim 1.

[0063] (Appendix 4) The irradiator; The imager further comprises: The irradiator includes: A plurality of light sources; an optical system that outputs each of the light beams emitted from the plurality of light sources toward the surrounding road surface as diffused light of the reference emission pattern, 4. A step detection device according to any one of claims 1 to 3.

[0064] (Appendix 5) the optical system is a light blocking member having a plurality of circular slits through which the light emitted from the plurality of light sources passes; the area of ​​each of the slits is larger than the emission area of ​​each of the light sources; The plurality of slits are provided in a one-to-one correspondence with the plurality of light sources, The light emitted from each of the light sources passing through each of the slits constitutes one of the reference emission patterns. 5. A step detection device as described in appendix 4.

[0065] (Appendix 6) A route estimation unit is configured to estimate a route along which the vehicle is to travel on the surrounding road surface based on a steering angle of the vehicle. The emission control unit causes the illuminator to emit diffused light of the reference emission pattern toward the planned travel route. A step detection device according to any one of Supplementary Note 1 to Supplementary Note 5.

[0066] (Appendix 7) The plurality of light sources illuminate the surrounding road surface in front of or behind the vehicle, the surrounding road surface being a predetermined first distance away from the vehicle; an illumination range of the plurality of light sources includes, when all of the plurality of light sources are on, all of the planned traveling routes assumed when the steering is varied from a maximum steering angle in one direction to a maximum steering angle in the other direction at a position separated from the vehicle by the first distance in a forward or backward direction of the vehicle; The emission control unit controls at least one of the plurality of light sources to be turned off in accordance with the planned traveling route estimated by the route estimation unit. 7. The step detection device according to claim 6.

[0067] (Appendix 8) The emission control unit controls a distance between at least one of the plurality of light sources and the optical system in accordance with the planned traveling route estimated by the route estimation unit. 8. The step detection device according to claim 7.

[0068] (Appendix 9) An image acquisition unit acquires an image of a road surface around the vehicle captured by an image capture device mounted on the vehicle, an emission control unit controls emission of light from an illuminator mounted on the vehicle toward the surrounding road surface; a step detection unit detects a step on the surrounding road surface based on the captured image; The emission control unit controls the illuminator to emit, toward the surrounding road surface, diffused light of a reference emission pattern capable of irradiating the surrounding road surface with a reference irradiation pattern when the surrounding road surface is a substantially flat road surface; The image acquisition unit extracts an actual irradiation pattern irradiated onto the surrounding road surface by the diffused light of the reference emission pattern from the captured image, the level difference detection unit detects the level difference by comparing a size of the actual irradiation pattern with a size of the reference irradiation pattern; Step detection method. [Explanation of symbols]

[0069] 11 emission control unit, 12 step detection unit, 13 output control unit, 14 path estimation unit, 21 irradiator, 22 imaging device, 23 warning notification unit, 24 vehicle controller, 25 steering, 31 vehicle, 33 curb, 34 reference road surface, 35 groove, 41 step, 42 reference road surface, 51 instrument panel, 52 speedometer, 53 tachometer, 54 display area, 56 route icon, 57 step icon, 61 irradiation range, 81 processing circuit, 82 processor, 83 memory, 101, 102 step detection device, 211 light source, 212 light shielding member, 212S, 212S1 slit, 213 control unit, 214 light shielding wall, 361, 362, 363, 364 diffused light, R1 reference irradiation range, R2 Step illumination range, T1, T2, T3 driving route.

Claims

1. an emission control unit that causes an illuminator mounted on the vehicle to emit, toward the surrounding road surface, diffused light of a reference emission pattern that can irradiate the surrounding road surface with a predetermined reference irradiation pattern when the surrounding road surface is a flat reference road surface; a step detection unit that extracts an actual irradiation pattern irradiated onto the surrounding road surface by the diffused light of the reference emission pattern from a photographed image of the surrounding road surface photographed by an imager mounted on the vehicle, and detects a step on the surrounding road surface based on a comparison of the size of the actual irradiation pattern and the size of the reference irradiation pattern. Step detection device.

2. and an output control unit that causes a warning notifier mounted on the vehicle to issue a visual or audio warning that the step exists based on the detection result of the step. The step detection device according to claim 1 .

3. the vehicle is an autonomous vehicle whose steering, acceleration, or deceleration can be controlled by a vehicle controller; an output control unit that causes the vehicle controller to control the vehicle so as to avoid the detected bump; The step detection device according to claim 1 .

4. the irradiator; The imager is further provided. The irradiator comprises: Multiple light sources; an optical system that outputs each of the light beams emitted from the plurality of light sources as diffused light of the reference emission pattern toward the surrounding road surface, The step detection device according to claim 1 .

5. the optical system is a light-blocking member provided with a plurality of circular slits through which the light emitted from the plurality of light sources passes, the area of ​​each of the slits is larger than the emission area of ​​each of the light sources; the plurality of slits are provided in a one-to-one correspondence with the plurality of light sources, the light emitted from each of the light sources passing through each of the slits constitutes one of the reference emission patterns; The step detection device according to claim 4 .

6. a route estimation unit that estimates, as an estimated route, a route that the vehicle is scheduled to travel on the surrounding road surface based on a steering angle of the vehicle; the emission control unit causes the illuminator to emit diffused light of the reference emission pattern toward the estimated path; The step detection device according to claim 5 .

7. the plurality of light sources illuminate the surrounding road surface in front of or behind the vehicle, the surrounding road surface being a predetermined first distance away from the vehicle; an illumination range of the plurality of light sources includes, when all of the plurality of light sources are on, all of the estimated paths that are assumed when the steering is varied from a maximum steering angle in one direction to a maximum steering angle in the other direction at a position that is separated from the vehicle by the first distance in a forward direction or a backward direction of the vehicle; the emission control unit controls at least one light source among the plurality of light sources to be turned off in accordance with the estimated route estimated by the route estimation unit. The step detection device according to claim 6.

8. the emission control unit controls a distance between at least one light source of the plurality of light sources and the optical system in accordance with the estimated path estimated by the path estimation unit. The step detection device according to claim 7.

9. an image acquisition unit acquires an image of a road surface around the vehicle captured by an image capture device mounted on the vehicle; an emission control unit controls emission of light from an illuminator mounted on the vehicle toward the surrounding road surface; a step detection unit detects a step on the surrounding road surface based on the captured image; the emission control unit controls the illuminator to emit, toward the surrounding road surface, diffused light of a reference emission pattern that can irradiate the surrounding road surface with a reference irradiation pattern when the surrounding road surface is a substantially flat road surface; The image acquisition unit extracts from the captured image an actual irradiation pattern irradiated onto the surrounding road surface by the diffused light of the reference emission pattern, the level difference detection unit detects the level difference by comparing the size of the actual irradiation pattern with the size of the reference irradiation pattern; Step detection method.

Images