Control device, optical sensor, control method, control program

Abstract

The processor of the control device is configured to perform: correlating the light reception intensity with each detection pixel for the detection distance and acquiring the light reception intensity in each detection cycle (Cd); monitoring a noise rate (R) of a number of noise pixels (Nn) relative to a number of correction pixels in each detection cycle (Cd), the number of correction pixels being a number of correction pixels after subtracting a number of effective pixels (Nv) of detection pixels that detected an effective echo (Erv) determined to be a reflection echo from the object from a total number (ΣN) of detection pixels, the number of noise pixels (Nn) being a number of detection pixels that detected a noise echo (Ern) determined to be a reflection echo from raindrops falling to the outside; and generating detection data (Dd) that informs a rain state of the outside according to the noise rate (R).

Description

Cross-reference of related applications

[0001] This application is based on Japanese Patent Application No. 2024-012279, filed on January 30, 2024, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0002] This disclosure relates to techniques for controlling optical sensors. Background Technology

[0003] Optical sensors that are controlled to receive reflected echoes from objects in response to projected light beams directed outwards and output detection data are well-known. For example, Patent Document 1 proposes a technique for detecting rainfall by controlling a LiDAR (Light Detection and Ranging) device, which functions as an optical sensor.

[0004] Existing technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 2021-109591 Summary of the Invention

[0005] However, although the technology proposed in Patent Document 1 can determine whether autonomous driving is possible based on the rainfall detection results of LiDAR that effectively utilizes the detection distance, it does not explicitly output the detection results themselves as an accurate indicator of the rainfall status.

[0006] The present disclosure addresses the need for a control device that effectively utilizes an optical sensor for detecting distance in providing an accurate output of rainfall conditions. Another objective of the present disclosure is to provide a control method that effectively utilizes an optical sensor for detecting distance in providing an accurate output of rainfall conditions. Yet another objective of the present disclosure is to provide a control program that effectively utilizes an optical sensor for detecting distance in providing an accurate output of rainfall conditions. A further objective of the present disclosure is to provide an optical sensor that effectively utilizes an optical sensor for detecting distance in providing an accurate output of rainfall conditions.

[0007] The technical means of this disclosure used to solve the problem will be described below.

[0008] The first aspect of this disclosure is a control device having a processor for controlling an optical sensor that receives reflected echoes from an object in each detection cycle in response to a projected light beam projected outwards and outputs detection data. The processor is configured to perform the following processes: For the detection distance to the target corresponding to the light-receiving timing of the reflected echo received by the optical sensor, the light intensity of the reflected echo received by the optical sensor is obtained in each detection cycle by establishing a correlation between each detection pixel of the detection data and the detection distance. In each detection cycle, the noise rate is monitored relative to the number of corrected pixels. The number of corrected pixels is the corrected pixel count, calculated by subtracting the number of valid echoes (identified as reflected echoes from a target) from the total number of detected pixels. The number of noise pixels is the number of detected pixels that are identified as reflected echoes from raindrops falling to the outside. Generate detection data to inform the outside world of rainfall status based on noise rate.

[0009] The second aspect of this disclosure is a control method executed by a processor for controlling an optical sensor that receives reflected echoes from an object in each detection cycle in response to a projected light beam projected outwards and outputs detection data. The control method includes: For the detection distance to the target corresponding to the light-receiving timing of the reflected echo received by the optical sensor, the light intensity of the reflected echo received by the optical sensor is obtained in each detection cycle by establishing a correlation between each detection pixel of the detection data and the detection distance. In each detection cycle, the noise rate is monitored relative to the number of corrected pixels. The number of corrected pixels is the corrected pixel count, calculated by subtracting the number of valid echoes (identified as reflected echoes from a target) from the total number of detected pixels. The number of noise pixels is the number of detected pixels that are identified as reflected echoes from raindrops falling to the outside. Generate detection data to inform the outside world of rainfall status based on noise rate.

[0010] The third aspect of this disclosure is a control program stored in a storage medium for controlling an optical sensor and containing commands for execution by a processor. The optical sensor receives reflected echoes from an object in response to a projected beam projected outwards in each detection cycle and outputs detection data. The control program contains commands for performing the following processes: For the detection distance to the target corresponding to the light-receiving timing of the reflected echo received by the optical sensor, the light intensity of the reflected echo received by the optical sensor is obtained in each detection cycle by establishing a correlation between each detection pixel of the detection data and the detection distance. In each detection cycle, the noise rate is monitored relative to the number of corrected pixels. The number of corrected pixels is the corrected pixel count, calculated by subtracting the number of valid echoes (identified as reflected echoes from a target) from the total number of detected pixels. The number of noise pixels is the number of detected pixels that are identified as reflected echoes from raindrops falling to the outside. Generate detection data to inform the outside world of rainfall status based on noise rate.

[0011] Thus, in the first to third methods, for the detection distance to the target corresponding to the light reception timing of the reflected echo by the optical sensor, the light intensity of the reflected echo is obtained in each detection cycle by establishing a correlation between the optical sensor and each detection pixel of the detection data. Therefore, the first to third methods focus on the correction pixel number, which is the number of effective pixels that are detected and determined to be effective echoes from the target, subtracted from the total number of detection pixels.

[0012] Specifically, according to the first to third methods, the noise rate is calculated in each detection cycle, which is the number of noise pixels that detect noise echoes identified as reflections from raindrops falling to the outside world, relative to the number of detection pixels that do not detect reflections from the target, i.e., the number of correction pixels. This allows the generation of detection data that indicates the rainfall status, based on the noise rate obtained by correcting the influence of noise echoes from raindrops that were not detected through the detection of valid echoes from the target. Therefore, optical sensors for detecting distances can be effectively utilized for accurate output of rainfall status based on the detection data.

[0013] The fourth aspect of this disclosure is a control device having a processor for controlling an optical sensor that receives reflected echoes from an object in each detection cycle in response to a projected light beam projected outwards and outputs detection data. The processor is configured to perform the following processes: For the detection distance to the target corresponding to the light-receiving timing of the reflected echo received by the optical sensor, the light intensity of the reflected echo received by the optical sensor is obtained in each detection cycle by establishing a correlation between each detection pixel of the detection data and the detection distance. The noise rate is defined as the ratio of the number of noise echoes to the number of corrected pixels in each detection cycle. The number of corrected pixels is the total number of detected pixels minus the number of detected pixels that are valid echoes determined to be from reflected echoes originating from an object (i.e., the number of valid pixels). The noise echoes are defined as reflected echoes determined to originate from raindrops falling to the outside. Generate detection data to inform the outside world of rainfall status based on noise rate.

[0014] The fifth aspect of this disclosure is a control method executed by a processor for controlling an optical sensor that receives reflected echoes from an object in each detection cycle in response to a projected beam projected outwards and outputs detection data. The control method includes: For the detection distance to the target corresponding to the light-receiving timing of the reflected echo received by the optical sensor, the light intensity of the reflected echo received by the optical sensor is obtained in each detection cycle by establishing a correlation between each detection pixel of the detection data and the detection distance. The noise rate is defined as the ratio of the number of noise echoes to the number of corrected pixels in each detection cycle. The number of corrected pixels is the total number of detected pixels minus the number of detected pixels that are valid echoes determined to be from reflected echoes originating from an object (i.e., the number of valid pixels). The noise echoes are defined as reflected echoes determined to originate from raindrops falling to the outside. Generate detection data to inform the outside world of rainfall status based on noise rate.

[0015] The sixth aspect of this disclosure is a control program stored in a storage medium for controlling an optical sensor and containing commands for execution by a processor. The optical sensor receives reflected echoes from an object in response to a projected beam projected outwards in each detection cycle and outputs detection data. The control program contains commands for performing the following processes: For the detection distance to the target corresponding to the light-receiving timing of the reflected echo received by the optical sensor, the light intensity of the reflected echo received by the optical sensor is obtained in each detection cycle by establishing a correlation between each detection pixel of the detection data and the detection distance. The noise rate is defined as the ratio of the number of noise echoes to the number of corrected pixels in each detection cycle. The number of corrected pixels is the total number of detected pixels minus the number of detected pixels that are valid echoes determined to be from reflected echoes originating from an object (i.e., the number of valid pixels). The noise echoes are defined as reflected echoes determined to originate from raindrops falling to the outside. Generate detection data to inform the outside world of rainfall status based on noise rate.

[0016] Thus, in the fourth to sixth methods, for the detection distance to the target corresponding to the light reception timing of the reflected echo by the optical sensor, the light intensity of the reflected echo is obtained in each detection cycle by establishing a correlation between the optical sensor and each detection pixel of the detection data. Therefore, the fourth to sixth methods focus on the correction pixel number, which is the number of effective pixels that are detected and determined to be effective echoes from the target, subtracted from the total number of detection pixels.

[0017] Specifically, according to methods four through six, the noise rate is defined as the ratio of the number of noise echoes identified as reflected echoes from raindrops falling to the outside world during each detection cycle to the number of detection pixels that do not detect reflected echoes from the target, i.e., the number of correction pixels. Thus, detection data indicating the rainfall status can be generated based on the noise rate obtained by correcting the influence of noise echoes from raindrops that were not detected through the detection of valid echoes from the target. Therefore, optical sensors for detecting distances can be effectively utilized for accurate output of rainfall status based on the detection data.

[0018] The seventh aspect of this disclosure is an optical sensor that receives reflected echoes from an object in response to a projected light beam projected outwards in each detection cycle and outputs detection data, comprising: The control unit is configured to include the control device described in the first or fourth manner, and generates detection data; The projection unit projects a beam of light according to the control of the control unit; and The light-receiving part receives the reflected echoes under the control of the control part.

[0019] Such a seventh type of optical sensor can achieve the same effect as the control device based on the first or fourth type. Attached Figure Description

[0020] Figure 1 This is a cross-sectional view showing the overall structure of the optical sensor according to the first embodiment.

[0021] Figure 2 This is a block diagram illustrating the functional structure of the optical sensor according to the first embodiment.

[0022] Figure 3 This is a schematic diagram showing the light-emitting light source unit of the first embodiment.

[0023] Figure 4 This is a schematic diagram showing the light-receiving detection unit of the first embodiment.

[0024] Figure 5 This is a schematic diagram used to illustrate the detection data of the first embodiment.

[0025] Figure 6 This is a flowchart illustrating the control flow of the first embodiment.

[0026] Figure 7 This is a diagram used to illustrate the control flow of the first embodiment.

[0027] Figure 8 This is a diagram used to illustrate the control flow of the first embodiment.

[0028] Figure 9This is a diagram used to illustrate the control flow of the first embodiment.

[0029] Figure 10 This is a diagram used to illustrate the control flow of the first embodiment.

[0030] Figure 11 This is a schematic diagram illustrating the control flow of the first embodiment.

[0031] Figure 12 This is a flowchart illustrating the control flow of the second embodiment.

[0032] Figure 13 This is a schematic diagram illustrating the detection data of the second embodiment.

[0033] Figure 14 This is a schematic diagram illustrating the relationship between the detection data and the detection field of view in the second embodiment.

[0034] Figure 15 This is a flowchart illustrating the control flow of the third embodiment.

[0035] Figure 16 This is a flowchart illustrating the control subroutine of the third implementation method.

[0036] Figure 17 This is a flowchart illustrating the control flow of the fourth embodiment.

[0037] Figure 18 This is a diagram used to illustrate the control flow of the fourth embodiment. Detailed Implementation

[0038] Hereinafter, several embodiments of the present disclosure will be described based on the accompanying drawings. Furthermore, in each embodiment, the same reference numerals are used to label corresponding constituent elements, and repeated descriptions are sometimes omitted. Additionally, where only a portion of the structure is described in each embodiment, structures from other previously described embodiments can be applied to the remaining parts of that structure. Moreover, not only combinations of structures explicitly shown in the descriptions of each embodiment are possible, but structures from multiple embodiments can be partially combined with each other even if not explicitly shown, provided that such combinations do not present particular obstacles.

[0039] like Figure 1As shown, the optical sensor 10 of the first embodiment of this disclosure is configured to be mounted on a moving body 1 and is a LiDAR (Light Detection and Ranging / Laser Imaging Detection and Ranging) for optically detecting the external environment of the moving body 1. The moving body 1, to which the optical sensor 10 is applied, is a vehicle, such as an automobile, capable of at least one of manual driving, autonomous driving, and remote driving. Furthermore, in the following description, unless otherwise stated, the directions shown as front, rear, up, down, left, and right are defined based on the moving body 1 on a horizontal plane. Additionally, in the following description, the horizontal direction and the vertical direction refer to the direction parallel to and perpendicular to the horizontal plane of the moving body 1, respectively. However, in… Figure 1 In the diagram, the portion to the left of the single-dot line along the vertical direction (the side of panel 12 described later) is actually illustrated as a cross section perpendicular to the portion to the right of the single-dot line (the sides of parts 21 and 41 described later).

[0040] The optical sensor 10 is disposed, for example, at at least one part of the moving body 1 in the front, left and right sides, rear, and upper roof. Figure 1 , Figure 2 As shown, the optical sensor 10 projects a projection beam Bp toward the detection area Ad, which corresponds to the placement location in the moving body 1 and the detection field of view in the outside world. The optical sensor 10 detects the reflected beam Er, which is the projection beam Bp reflected back by the object Ot in the detection area Ad. Thus, the projection beam Bp, which becomes the reflected echo Er, selects light in the near-infrared region, which is difficult for humans to visually confirm.

[0041] The optical sensor 10 detects an object Ot in the detection area Ad by receiving the reflected echo Er reflected relative to the projected beam Bp. Here, the detection of the object Ot refers to multiple sensing methods, including at least distance and intensity, such as the distance from the optical sensor 10 to the object Ot, the intensity of the reflected echo Er reflected from the object Ot, and the direction in which the object Ot exists.

[0042] The object Ot that serves as a representative detection target in the optical sensor 10 applied to the moving body 1 can be, for example, at least one of moving objects such as pedestrians, cyclists, animals other than humans, and other vehicles. The object Ot that serves as a representative detection target in the optical sensor 10 applied to the moving body 1 can also be, for example, at least one of stationary objects such as guardrails, road signs, roadside structures, and objects fallen on the road.

[0043] like Figure 1As shown, the optical sensor 10 includes a housing portion 11, a light-emitting portion 21, a scanning portion 31, a light-receiving portion 41, and a control portion 51. The light-shielding housing portion 11 is formed into a box shape, for example, by metal or resin. The housing portion 11 houses the light-emitting portion 21, the scanning portion 31, and the light-receiving portion 41 inside. An opening in the housing portion 11 that extends through the inside and outside is closed by a cover panel 12. The light-transmitting cover panel 12 is formed, for example, by resin or glass, and separates the inside and outside of the housing portion 11. Thus, the outer surface of the cover panel 12 forms a detection surface 12a exposed to the outside in the optical sensor 10.

[0044] like Figure 1 , Figure 2 As shown, the light-projecting unit 21 includes a light-projecting light source unit 22 and a light-projecting lens unit 26. (As shown...) Figure 3 As shown, the light source unit 22 is constructed by mounting multiple light source elements 24 in an array on a substrate. Each light source element 24 is arranged in a single row along the vertical direction. Figure 3 Examples of laser diodes (e.g., multiple rows, not shown in the diagram) are used. Each light source element 24 generates laser light in a pulsed manner as a part of the projected beam Bp according to the control signal from the control unit 51. Each light source element 24 can be an edge-emitting laser or a vertical-cavity surface-emitting laser (VCSEL).

[0045] The light source unit 22 has a light source window 25 formed on one side of the substrate. The light source window 25 is simulated to have a rectangular outline that is longer in the vertical direction and shorter in the horizontal direction. The light source window 25 is configured as an aggregation of laser oscillation openings in each light source element 24. Laser light projected from the laser oscillation openings of each light source element 24 is projected from the light source window 25 as a projection beam Bp, which is assumed to be a linear beam that is longer in the vertical direction, at least in the external detection area Ad.

[0046] like Figure 1 As shown, the projection lens unit 26 is configured such that at least one projection lens 27 is held within the lens barrel 28. The light-transmitting projection lens 27 is primarily made of a substrate such as resin or glass and is formed into a lens shape corresponding to the optical function it performs. The projection lens 27 performs at least one optical function on the projected beam Bp from the projection light source unit 22, such as focusing, collimation, and shaping. The projection lens 27 is positioned within a light-shielding lens barrel 28, for example, made of metal or resin. By aligning with the projection light source unit 22, the projection lens unit 26 with this structure forms a projection optical axis that guides the projected beam Bp toward the scanning section 31.

[0047] like Figure 1 , Figure 2As shown, the scanning unit 31 includes a scanning mirror 32 and a scanning motor 35. The scanning mirror 32 is constructed as a plate with a reflective film deposited on a single reflective surface 33, which serves as a substrate. The scanning mirror 32 is supported by the housing 11 and is rotatable about a rotation center line along the vertical direction. The scanning mirror 32 oscillates within a drive range defined by mechanical or electrical stops.

[0048] The scanning motor 35 is, for example, a voice coil motor, a brushed DC motor, or a stepper motor. The output shaft of the scanning motor 35 is directly or indirectly connected to the scanning mirror 32 via a drive mechanism such as a reducer. The scanning motor 35 is held by the housing 11 in such a way that it can drive the scanning mirror 32 to rotate together with the output shaft. The scanning motor 35 rotates (i.e., oscillates) the scanning mirror 32 within a limited drive range according to the control signal from the control unit 51.

[0049] The scanning mirror 32 reflects the projected light beam Bp incident from the projection section 21 through the reflective surface 33 and projects it onto the detection area Ad through the cover panel 12, thereby scanning the area Ad according to the rotation angle of the scanning motor 35. At this time, the scanning of the detection area Ad by the projected light beam Bp is driven by the rotation of the scanning mirror 32, and in this embodiment, it is substantially limited to scanning in the horizontal direction.

[0050] The scanning mirror 32 reflects the reflected echo Er, which is incident on the target Ot in the detection area Ad through the cover panel 12, towards the light-receiving part 41 according to the rotation angle of the scanning motor 35 via the reflecting surface 33. At this time, the speed of the projected beam Bp and the reflected echo Er are sufficiently large relative to the rotational speed of the scanning mirror 32. As a result, the reflected echo Er is reflected by the scanning mirror 32, which can simulate the rotation angle relative to the projected beam Bp as substantially the same, and thus guides the light towards the light-receiving part 41 in a manner that is opposite to the projected beam Bp.

[0051] The light-receiving unit 41 includes a light-receiving lens unit 42 and a light-receiving detection unit 45. For example... Figure 1 As shown, the light-receiving lens unit 42 is constructed such that at least one light-receiving lens 43 is held by a lens barrel 44. The light-transmitting light-receiving lens 43 is mainly composed of a substrate such as resin or glass, and is formed into a lens shape corresponding to the optical function it performs. The light-receiving lens 43 performs an optical function by imaging the reflected echo Er from the scanning mirror 32 onto the light-receiving detection unit 45. The light-receiving lens 43 is positioned within a light-shielding lens barrel 44, for example, made of metal or resin. The light-receiving lens unit 42 with this structure is formed by aligning it with the light-receiving detection unit 45 such that the light-receiving optical axis that guides the reflected echo Er from the scanning unit 31 to the side of the unit 45 is offset from the projection optical axis of the projection lens unit 26 in the vertical direction.

[0052] like Figure 4As shown, the light-receiving detection unit 45 is constructed by mounting a plurality of light-receiving pixels 46 in an array on a substrate. Each light-receiving pixel 46 is arranged at least along the vertical direction. The light-receiving detection unit 45 forms a light-receiving surface 450 on one side of the substrate, which has a rectangular outline that is longer along the vertical direction and shorter along the horizontal direction. The light-receiving surface 450 is configured as an assembly of the incident surfaces of each light-receiving pixel 46. Each light-receiving pixel 46 is composed of, for example, a single-photon avalanche diode, which serves as a plurality of light-receiving elements 460. Figure 1 As shown, each of these light-receiving pixels 46 receives the reflected echo Er incident from the light-receiving lens unit 42 onto the light-receiving surface 450.

[0053] like Figure 1 , Figure 2 As shown, an output circuit 47 is provided in the light-receiving detection unit 45. The output circuit 47 outputs power according to the control signal from the control unit 51 during each detection cycle Cd (see below). Figure 5 The scanning mirror 32 is rotated at an angle corresponding to the rotation angle of the projection light source unit 22, and the sampling process is performed along the scan lines. The rotation angle of the scanning mirror 32 is synchronized with the projection timing of the projection beam Bp. At this time, the output circuit 47 synthesizes the response outputs from the light-receiving elements 460 of each light-receiving pixel 46 according to each detection cycle Cd, thereby generating a detection signal. The generated detection signal is then output from the output circuit 47 to the control unit 51 along the scan lines.

[0054] The control unit 51 is composed of a control device that includes at least one dedicated computer and is mounted on a substrate. The dedicated computer constituting the control unit 51 may also be a sensor ECU (Electronic Control Unit) specifically for controlling the optical sensor 10; in this case, the sensor ECU is housed within the housing 11. Figure 1 (Example). The dedicated computer constituting the control device of the control unit 51 may also be an operation control ECU specifically used to control the operation of the mobile body 1. In this case, the operation control ECU is disposed outside the housing 11 in the mobile body 1 (illustration omitted).

[0055] like Figure 1As shown, the dedicated computer constituting the control unit 51 has at least one memory 51a and one processor 51b. The memory 51a is a non-transitory tangible storage medium, such as semiconductor memory, magnetic medium, and optical medium, that non-transitorily stores programs and data that can be read by the computer. The processor 51b includes, for example, at least one of the following as a core: CPU (Central Processing Unit), GPU (Graphics Processing Unit), RISC (Reduced Instruction Set Computer) CPU, DFP (Data Flow Processor), and GSP (Graph Streaming Processor).

[0056] The control unit 51, with this structure, is connected to the light-emitting light source unit 22, the scanning motor 35, and the light-receiving detection unit 45. The control unit 51 controls the light-emitting light source unit 22 to generate a projected beam Bp according to each detection cycle Cd. Simultaneously, the control unit 51 controls the scanning motor 35 to control the scanning and reflection of the scanning mirror 32, which is synchronized with the light-emitting timing of the light-emitting light source unit 22, according to each detection cycle Cd. Furthermore, the control unit 51 processes the detection signal output from the output circuit 47 of the light-receiving detection unit 45, which is controlled according to the light-emitting of the light-emitting light source unit 22 and the scanning and reflection of the scanning mirror 32, according to each detection cycle Cd.

[0057] Therefore, the control unit 51 can express the detection distance L up to the object Ot in the detection area Ad and the light intensity I of the reflected echo Er from the object Ot in each detection cycle Cd (L and I are described later). Figures 7-10 Generate in the way of ) Figure 5 The detection data Dd shown is output to the moving body 1. At this time, in the detection data Dd, even if the detection distance L and the light intensity I are detected by the same physically lit pixel 46, such as Figure 5 As shown, different scan lines α within the detection period Cd are also reflected in each other as data values ​​that establish association with other detection pixels 46a.

[0058] To specifically implement such control, processor 51b executes multiple commands contained in the control program stored in memory 51a. Thus, control unit 51 constructs multiple functional blocks for controlling optical sensor 10. For example... Figure 2As shown, the multiple functional blocks constructed by the control unit 51 include a detection block 100, a monitoring block 110, and a data generation block 120.

[0059] Through the cooperation of these blocks 100, 110, and 120, the control unit 51 controls the optical sensor 10 according to the control method. Figure 6 The control flow shown is executed repeatedly according to each detection cycle Cd during the startup of moving body 1. Furthermore, each "S" in the control flow refers to a multiple step executed by multiple commands contained in the control program.

[0060] In S100, the detection block 100 obtains the detection signals of each scan line α in the current detection cycle Cd from the output circuit 47. In the following S110, the detection block 100 generates light-receiving data Dr (refer to...) for all detected pixels 46a in the light-receiving detection unit 45 based on the detection signals of each scan line α obtained in the current detection cycle Cd. Figure 5 ).

[0061] Specifically, in S110, the detection distance L to the target Ot is obtained based on the elapsed time from the projection timing of the projected beam Bp from the projection light source unit 22 to the light receiving timing at the peak of the reflected echo Er from the light receiving detection unit 45. The obtained detection distance L is used as the data value of the light receiving data Dr used in the generation of the detection data Dd described later, and is associated with each detection pixel 46a according to the detection data Dd. At the same time, in S110, the light receiving intensity I at the peak of the reflected echo Er from the light receiving detection unit 45 is also obtained and associated with each detection pixel 46a as the data value of the light receiving data Dr. At this time, the light receiving intensity I of the reflected echo Er can be corrected, for example, by subtracting the intensity of the background light estimated based on the light receiving intensity I associated with the detection pixel 46a that did not detect the peak of the reflected echo Er. Thus, in the light receiving data Dr, the detection distance L and the light receiving intensity I are also associated with each detection pixel 46a respectively.

[0062] In the following S120, the monitoring block 110 determines the type of reflected echo Er detected by each detection pixel 46a based on the light-receiving data Dr generated for the current detection cycle Cd. For example... Figures 7-9 As shown, the reflected echo Er of a given type includes noise echo Ern and effective echo Erv. Therefore, in order to determine the noise echo Ern and the effective echo Erv respectively, the noise range Lin and the effective range Liv are defined.

[0063] Specifically, the noise range LIn and the effective range LIV are as follows: Figures 7-10As shown, regarding the light intensity I, the threshold intensity It corresponding to the detection distance L is defined as the upper and lower limits, respectively. The threshold intensity It is set to decrease monotonically as the detection distance L increases. The threshold intensity It can be as follows: Figures 7-10 As illustrated, the greater the detection distance L, the more gradually the rate of reduction per unit distance decreases.

[0064] like Figures 7-10 As shown, the noise range Lin and the effective range Liv are further defined with respect to the detection distance L as a range greater than the near threshold distance Lt1 and less than the far threshold distance Lt2. The near threshold distance Lt1 is set to a range exceeding zero, corresponding to the position of the detection surface 12a in the optical sensor 10, for example, in the separation distance between the detection surface 12a and the light-receiving surface 450. The far threshold distance Lt2 is set to a distance corresponding to the detection limit distance of the optical sensor 10, for example, the separation distance between the far point of the depth of field provided by the light-receiving lens unit 42 and the detection surface 12a.

[0065] Through this specification and setting, the noise range LIn is used to determine the reflected echo Er from the detection distance L, which is above the near threshold distance Lt1 and below the far threshold distance Lt2. Figure 7 , Figure 8 The condition range shown is for noise echo Ern that is below the threshold intensity It, where the light intensity I is the upper limit boundary. Therefore, even if the light intensity I is below the threshold intensity It, reflected echo Er at a detection distance L that is less than the near threshold distance Lt1 or greater than the far threshold distance Lt2 is excluded from the determination of noise echo Ern. On the other hand, the effective range Liv becomes the range used to determine reflected echo Er from detection distances L that are greater than the near threshold distance Lt1 and less than the far threshold distance Lt2. Figure 9 The condition range for valid echo Erv is shown when the light intensity I exceeds the threshold intensity It at the lower limit boundary. Therefore, even if the light intensity I exceeds the threshold intensity It, the reflected echo Er is excluded from the determination of valid echo Erv if the detection distance L is less than the near threshold distance Lt1 or exceeds the far threshold distance Lt2.

[0066] In addition, Figures 7-10 In the example, the near-field threshold distance Lt1 is set to a common value in both the noise range Lin and the effective range Liv, but it can also be set to different values ​​in the noise range Lin and the effective range Liv. The far-field threshold distance Lt2 is... Figures 7-10In the example, both the noise range Lin and the effective range Liv are set to the same value, but they can also be set to different values. Regarding the light intensity I, a noise range Lin less than the threshold intensity It and an effective range Liv greater than the threshold intensity It can also be used for the detection distance L that is above the near threshold distance Lt1 and below the far threshold distance Lt2.

[0067] exist Figure 6 In S120, the reflected echo Er, associated with the detection distance L and the light intensity I within the noise range LIn of the detected pixel 46a, is defined as the noise echo Ern. In the first embodiment, the earliest reflected echo Er within the current detection period Cd of each detected pixel 46a is defined as... Figure 7 , Figure 8 The noise echo Er is determined by the reflected echo Er within the noise range Lin, based on the detection distance L and the light intensity I shown. Here, the earliest light timing is equivalent to the shortest detection distance L within the noise range Lin, assigned light intensity I according to the detection pixel 46a, in the current detection period Cd. The noise echo Er determined in this way is distinguished from the reflected echo Er from the object Ot that is originally the object to be detected, and is defined as the reflected echo Er from raindrops falling to the outside.

[0068] On the other hand, in S120, the reflected echo Er associated with the detection distance L and the light intensity I within the effective range LIV of the detection pixel 46a is determined as the effective echo Erv. At this time, in the first embodiment, according to the detection pixel 46a, the earliest reflected echo Er in the current detection cycle Cd is selected, such as... Figure 9 The detection distance L and the light intensity I are defined as the reflected echo Er within the effective range Liv, and the effective echo Erv is determined. Here, the earliest light receiving timing is equivalent to the shortest detection distance L within the effective range Liv assigned light intensity I by detection pixel 46a in the current detection period Cd. The effective echo Erv determined in this way is defined as the reflected echo Er from the object Ot other than raindrops.

[0069] like Figure 6 As shown, in the following S130, monitoring block 110 extracts the Cd value for the current detection cycle. Figure 11 The number of noise pixels shown is used as the detection pixel 46a for the noise echo Ern determined by S120. That is, in Figure 6 In step S130, the number of noise pixels Nn, i.e., the number of noise pixels Nn, that are detected as noise echo Ern in the current detection cycle Cd, is counted. Simultaneously, in S130, the monitoring block 110 extracts the data for the current detection cycle Cd. Figure 11The number of effective pixels shown is used as the number of detection pixels 46a for which the effective echo Erv was determined via S120. That is, in Figure 6 In S130, the number of valid pixels (Nv) that detect valid echo Erv in the current detection cycle Cd is also counted.

[0070] like Figure 6 As shown, in the following S140, the monitoring block 110 monitors the noise rate R, which is counted by S130 and related to the number of noise pixels Nn and the number of effective pixels Nv, for the current detection period Cd. At this time, the noise rate R is defined according to Equation 1 as the proportion of the number of noise pixels Nn relative to the number of corrected pixels after subtracting the number of effective pixels Nv from the total number of detected pixels 46a ΣN. Here, particularly as described above, in the first embodiment where the noise echo Ern is limited to the earliest reflected echo Er, the number of noise pixels Nn is substantially the same as the number of noise echo Ern. Therefore, the noise rate R of the first embodiment is also equivalent to the proportion of the number of noise echo Ern relative to the number of corrected pixels after subtracting the number of effective pixels Nv from the total number of detected pixels 46a ΣN.

[0071] Formula 1 At this time, during the monitoring in S140, the number of noise pixels Nn and the number of effective pixels Nv can also be limited to the values ​​in the current detection period Cd. During the monitoring in S140, for each of the number of noise pixels Nn and the number of effective pixels Nv, in addition to the value in the current detection period Cd, an average value obtained by averaging the values ​​accumulated over a set number of past detection periods Cd can also be used. Here, when using the latter average value, the set number of past values ​​added to the current value can be, for example, preset to the most recent 9 times, so that the value of 10 values ​​is averaged in the total of the current and past values.

[0072] like Figure 6As shown, in the following S150, the data generation block 120 generates detection data Dd to be output to the moving body 1, such that it includes light-receiving data Dr containing the amount of all detected pixels 46a, and notifies the outside world of the rainfall status based on the noise rate R monitored by S140. At this time, the rainfall status can also be output based on the detection data Dd as diagnostic information notifying the amount of rainfall Q at each set time, which is defined according to the following Equation 2 using a function F of a monomial or polynomial as a physical quantity related to the noise rate R. The rainfall status can also be output based on the detection data Dd as a warning message notifying of heavy rainfall in response to the noise rate R rising above or exceeding the warning range of the noise threshold. Here, the warning range can be preset to the range of noise rate R corresponding to the amount of rainfall that requires a warning to the moving body 1 equipped with the optical sensor 10.

[0073] Formula 2 Thus, during the startup of mobile body 1, if the current execution of the control flow in the current detection cycle Cd ends due to the completion of S150, the next execution of the control flow in the next detection cycle Cd will begin.

[0074] (Effects) The effects of the first embodiment described above will be explained below.

[0075] In the first embodiment, for the detection distance L to the target Ot corresponding to the light reception timing of the reflected echo Er by the optical sensor 10, the light intensity I of the reflected echo Er by the optical sensor 10 is associated with the detection pixel 46a of the detection data Dd and acquired in each detection cycle Cd. Therefore, the first embodiment focuses on the correction pixel number, which is the number of effective pixels Nv of the detection pixels 46a that have detected the effective echo Erv determined to be the reflected echo Er from the target Ot, subtracted from the total number ΣN of the detection pixels 46a.

[0076] Specifically, according to the first embodiment, in each detection cycle Cd, the noise pixel number Nn of the noise echo Ern, which is determined to be the reflected echo Er from raindrops falling to the outside, is monitored relative to the number of detection pixels 46a of the undetected reflected echo Er from the target Ot, i.e., the number of correction pixels, representing the noise rate R. Here, the noise rate R in the first embodiment can also be described as the ratio of the number of noise echo Ern to the number of correction pixels. Based on such monitoring, detection data Dd of the rainfall state can be generated, which is the noise rate R obtained by correcting the influence of the undetected noise echo Ern from raindrops based on the detection of the effective echo Erv from the target Ot. Therefore, the optical sensor 10 with a detection distance L can be effectively utilized for accurate output of the rainfall state based on the detection data Dd.

[0077] According to the first embodiment, within a noise range LIn with an upper limit boundary of a threshold intensity It that decreases as the detection distance L increases with increasing light intensity I, the reflected echo Er associated with the detection distance L and the light intensity I for each detection pixel 46a is determined as noise echo Ern. Therefore, noise echo Ern from raindrops falling to the outside can be accurately identified from the reflected echo Er of each detection pixel 46a. Furthermore, regarding light intensity I, within an effective range LIV with a lower limit boundary of the threshold intensity It, the reflected echo Er associated with the detection distance L and the light intensity I for each detection pixel 46a is determined as effective echo Erv. Therefore, effective echo Erv from the target Ot can be accurately identified from the reflected echo Er of each detection pixel 46a. Thus, by monitoring the noise rate R, which reflects the determination results of accurately identified noise echo Ern and effective echo Erv, the output accuracy of the rainfall state corresponding to the noise rate R can be improved.

[0078] According to the first embodiment, for each detection pixel 46a, the earliest reflected echo Er in each detection period Cd, whose detection distance L and light intensity I are within the noise range Lin, is determined as the noise echo Ern. On the other hand, for each detection pixel 46a, the earliest reflected echo Er in each detection period Cd, whose detection distance L and light intensity I are within the effective range Liv, is determined as the effective echo Erv. By determining these noise echoes Ern and effective echoes Erv, the processor 51b can quickly determine the number of noise pixels Nn and the number of effective pixels Nv corresponding to each echo, thus shortening the generation time for outputting the detection data Dd corresponding to the rainfall state with noise rate R.

[0079] According to the first embodiment, among the reflected echoes Er within the noise range Lin of the detection distance L and the light intensity I, the noise echo Er is determined by defining the earliest light-receiving echo Er in each detection cycle Cd as defined by the detection pixel 46a. Therefore, from determining the noise echo Er to knowing the number of noise pixels Nn, the processing speed of the processor 51b can be increased, thus improving the time required to generate detection data Dd for outputting the rainfall state corresponding to the noise rate R.

[0080] According to the first embodiment, the noise echo Ern and the effective echo Erv are determined based on the reflected echo Er at a detection distance L greater than or equal to the detection surface 12a exposed to the outside environment in the optical sensor 10 at a proximity threshold distance Lt1. Conversely, reflected echo Er at a detection distance L less than the proximity threshold distance Lt1 is excluded from the determination of the noise echo Ern and the effective echo Erv. Thus, reflected echo Er caused by factors other than raindrops, such as obstructions or dirt on the detection surface 12a, can be excluded, and the noise echo Ern and the effective echo Erv can be accurately determined. Therefore, by monitoring the noise rate R, which reflects such accurate determination results, the output accuracy of the rainfall state corresponding to the noise rate R can be improved.

[0081] According to the first embodiment, the detection data Dd can also be generated by notifying the rainfall status as the rainfall amount Q, which is related to the noise rate R. In this case, the rainfall status can be accurately output based on the rainfall amount Q.

[0082] According to the first embodiment, detection data Dd can also be generated in a manner that notifies the user of the rainfall status in response to a situation where the noise rate R rises to a warning range that warns the mobile body 1 equipped with the optical sensor 10. In this case, it is not limited to accurately outputting the rainfall status corresponding to the noise rate R within the warning range, but the optical sensor 10 can also be effectively used to ensure the safety of the mobile body 1 during movement.

[0083] (Second Implementation) The second embodiment is a variation of the first embodiment. For example... Figure 12 As shown, in the control flow of the second embodiment, S2130, S2140, and S2150, which respectively replace S130, S140, and S150 of the first embodiment, are executed independently for multiple pixel regions 46b. Here, each pixel region 46b is as follows: Figure 13 As shown in the shading of points with different roughness, each is defined as containing a predetermined number of detection pixels 46a, thereby respectively relating to the entire detection field of view Vd of all scan lines α of the optical sensor 10, as shown in the figure. Figure 14 The partitioned Vdb corresponds to the partition shown.

[0084] Specifically, in S2130, the monitoring block 110 counts the number of pixels Nn and Nv according to each pixel region 46b. Therefore, in S2140, the monitoring block 110 monitors the noise rate R according to the pixel region 46b. Furthermore, in S2150, the data generation block 120 generates detection data Dd, which contains the light-receiving data Dr of all detected pixels 46a, and notifies the rainfall status corresponding to the noise rate R according to the pixel region 46b. Thus, during the startup of the moving body 1, if the execution of the control flow in the current detection cycle Cd ends upon completion of S2150, the next execution of the control flow in the next detection cycle Cd begins.

[0085] According to this second embodiment, since the noise rate R is monitored in pixel regions 46b, each containing a predetermined number of detection pixels 46a, the rainfall status of each segmented partition Vdb corresponding to each pixel region 46b in the detection field of view Vd can be output based on the detection data Dd. Therefore, even for a relatively wide detection field of view Vd, the rainfall status can be detailed for each segmented partition Vdb.

[0086] (Third implementation method) The third embodiment is a variation of the first embodiment. For example... Figure 15 As shown, in the control flow of the third embodiment, S3140, which replaces S140 and S150 of the first embodiment, is executed.

[0087] Specifically, in S3140, execution Figure 16 The control subroutine is shown. In S3141 of this control subroutine, the monitoring block 110, as the value of the effective pixel number Nv, extracts, in addition to the value counted by S130 for the current detection period Cd, the average value obtained by averaging the values ​​of the past detection periods Cd counted by S130 for a set number of past detection periods. Here, in the extraction of the effective pixel number Nv, the set number of past values ​​added to the current value can be preset to, for example, the most recent 9 times, so that the value of 10 values ​​is averaged in the sum of the current and past values.

[0088] In step S3141, monitoring block 110 determines whether the average value of the current and past effective pixel counts Nv has decreased below a first effective threshold or is within a monitoring range of the first effective threshold. Here, the monitoring range can be preset to the range of effective pixel count Nv for which the noise rate R needs to be monitored, assuming a rainfall condition where the effective pixel count Nv decreases. If a positive determination is made in S3141, the control subroutine proceeds to S3142.

[0089] In S3142, monitoring block 110 monitors the noise rate R related to the number of noisy pixels Nn and the number of effective pixels Nv according to Formula 1 of the first embodiment. That is, in S3142, the noise rate R related to the number of effective pixels Nv when it is reduced to the monitoring range is monitored. However, at this time, the value of the number of effective pixels Nv is the average value, just like in S3141. On the other hand, the value of the number of noisy pixels Nn is the average value obtained by averaging the values ​​obtained by accumulating the values ​​of the detection cycles Cd of the current quantity in S130, in addition to the value obtained by counting the detection cycles Cd of the past set number of times in S130. Here, the set number of past quantities added to the current quantity in the extraction of the number of noisy pixels Nn can be preset to, for example, the most recent 9 times, so that the value of 10 quantities in the sum of the current and past quantities is averaged.

[0090] In step S3142, the monitoring block 110 determines whether the noise rate R monitored based on the average of the current and past pixel counts Nn and Nv has risen above a first noise threshold or exceeded the warning range of the first noise threshold. Here, the warning range can be preset to the range of noise rate R corresponding to the amount of rainfall that requires a warning to the moving body 1 equipped with the optical sensor 10. If an affirmative determination is made by step S3142, the control subroutine moves to step S3143.

[0091] In S3143, the data generation block 120 generates detection data Dd using light-receiving data Dr containing all the detected pixels 46a and in a manner that notifies the outside world of rainfall status based on the noise rate R monitored by S3142. At this time, the rainfall status is output as a warning message indicating heavy rainfall in response to the noise rate R rising above or exceeding the warning range of the first noise threshold, based on the detection data Dd.

[0092] If a negative determination is made in S3142, the control subroutine moves to S3144. In S3144, the monitoring block 110, as in S3142, determines whether the noise rate R monitored based on the average of the current and past pixel numbers Nn and Nv has decreased to below the second noise threshold or is within the clearance rate range of the second noise threshold. Here, the clearance rate range is the range of noise rate R corresponding to the amount of rainfall that can clear the warning to the moving body 1, and can be preset to a range where the noise rate R is smaller than the warning range.

[0093] Furthermore, if a negative determination is made in S3141 above, the control subroutine moves to S3145. In S3145, the monitoring block 110, in the same manner as in S3141, determines whether the average value of the extracted current and past effective pixel counts Nv rises above or exceeds the second effective threshold or exceeds the range of the number of pixels to be removed from the second effective threshold. Here, the range of the number of pixels to be removed is the range of effective pixel counts Nv corresponding to the amount of rainfall that can remove the warning for the moving body 1, and can be preset to a range where the effective pixel count Nv is larger than the monitoring range.

[0094] If a positive determination is made through any of these S3144 and S3145, the control subroutine moves to S3146. In S3146, the data generation block 120 generates light-receiving data Dr containing the amount of all detected pixels 46a and outputs detection data Dd in a manner that signals the end of the rain condition.

[0095] On the other hand, if a negative decision is made via either S3144 or S3145, the control subroutine moves to S3147. In S3147, the data generation block 120 generates detection data Dd, which contains the light-receiving data Dr of all detected pixels 46a, and outputs the notification or cancellation decision based on any one of S3143, S3146, or S3147 regarding the rainfall status in the previous detection cycle Cd. Here, in the rainfall-related decision in the previous detection cycle Cd, particularly in S3147, the notification or cancellation decision from the detection cycle Cd last executed via S3143 or S3146 two weeks prior is inherited.

[0096] Thus, during the startup of mobile body 1, if the current execution of the control flow and control subroutine in the current detection cycle Cd ends due to the completion of any one of S3143, S3146, and S3147, then the next execution of the control flow in the next detection cycle Cd will begin.

[0097] According to the third embodiment described above, detection data Dd is generated in a manner that notifies the user of the rainfall status in response to a situation where the noise rate R rises to a warning range that would alert the moving body 1 equipped with the optical sensor 10. Therefore, not only is the accurate output of the rainfall status corresponding to the noise rate R within the warning range not limited, but the optical sensor 10 can also be effectively utilized to ensure the safety of the moving body 1 during movement.

[0098] Furthermore, according to the third embodiment, the noise rate R is monitored in relation to the effective pixel count Nv (specifically, its average value) when it decreases to within the monitoring range. Therefore, during the period when the effective pixel count Nv rises outside the monitoring range, it can be inferred that the noise pixel count Nn corresponding to rainfall has decreased, and thus it is possible to immediately determine that the noise rate R has decreased to outside the warning range without performing this monitoring. Therefore, the generation time of detection data Dd in cases where the determination of rainfall status corresponding to the noise rate R is substantially unnecessary can be shortened.

[0099] (Fourth Implementation) The fourth embodiment is a variation of the first embodiment. For example... Figure 17 As shown, in the control flow of the fourth embodiment, S4120, S4130, S4140, and S4150, which respectively replace S120, S130, S140, and S150 of the first embodiment, are executed.

[0100] Specifically, in S4120, such as Figure 18 As shown, the monitoring block 110 determines all reflected echoes Er detected within the noise range Linn, that have the same detection period Cd according to the detection pixel 46a, and that are within the noise range Linn of the detection distance L and the light intensity I. That is, if it is the light intensity I within the noise range Linn, not only is the earliest reflected echo Er with the earliest light timing in the current detection period Cd determined as a different noise echo Ern for each detection pixel 46a, but also the reflected echoes Er with the second or subsequent light timing in the current detection period Cd are determined as different noise echoes Ern for each detection pixel 46a. Here, the second or subsequent light timing is equivalent to the detection distance L of the light intensity I within the noise range Linn assigned to the detection pixel 46a becoming the second or subsequent from the shorter side in the current detection period Cd. However, the determination of the effective echo Erv based on S4120 is performed according to S120 of the first embodiment.

[0101] In this fourth embodiment, in the following S4130, as Figure 17 As shown, the monitoring block 110 counts the total number of noise echoes Ern detected in the detection pixel 46a during the current detection cycle Cd as the noise determination number Nne, replacing the noise pixel number Nn. However, the counting of the effective pixel number Nv based on S4130 is performed according to S130 of the first embodiment.

[0102] Furthermore, in the following S4140, the monitoring block 110 monitors the noise rate R, which is counted by S4130 and is related to the noise determination number Nne and the effective pixel number Nv, for the current detection cycle Cd. At this time, the noise rate R is defined according to Equation 3 below, based on the proportion of the noise determination number Nne to the number of corrected pixels after subtracting the effective pixel number Nv from the total number of detected pixels ΣN.

[0103]

Formula 3

[0104]

Formula 4

[0105] Thus, the fourth embodiment also focuses on the corrected pixel number, which is calculated by subtracting the effective pixel number Nv of the detection pixels 46a that detected the effective echo Erv of the reflected echo Er determined to be from the object Ot from the total number of detection pixels ΣN. However, according to the fourth embodiment, the noise determination number Nne, which monitors the number of noise echoes Ern determined to be from raindrops falling to the outside in each detection cycle Cd, is relative to the number of detection pixels 46a that did not detect the reflected echo Er from the object Ot, i.e., the corrected pixel number, as the noise rate R. Therefore, it is possible to generate detection data Dd that informs the rainfall state based on the noise rate R obtained by correcting the influence of the noise echo Ern not detected from raindrops through the detection of the effective echo Erv from the object Ot. Therefore, the optical sensor 10 with a detection distance L can be effectively utilized for accurate output of the rainfall state based on the detection data Dd.

[0106] Furthermore, according to the fourth embodiment, all reflected echoes Er detected by detection pixel 46a in the same detection cycle Cd within the noise range Lin of the detection distance L and the light intensity I are within the noise range Lin. Therefore, noise echoes Ern reflected by raindrops at different detection distances L from the optical sensor 10 can be determined by detection pixel 46a and in each detection cycle Cd and reflected in the noise rate R, thus improving the output accuracy of the rainfall state corresponding to the noise rate R.

[0107] (Other implementation methods) The above describes several embodiments, but this disclosure is not limited to these embodiments and can be applied to various embodiments and combinations without departing from the spirit of this disclosure.

[0108] In a variation, the dedicated computer constituting the control unit 51 may also have at least one of digital circuitry and analog circuitry as a processor. Here, the digital circuitry may be at least one of an ASIC (Application Specific Integrated Circuit), a FPGA (Field Programmable Gate Array), a SOC (System on a Chip), a PGA (Programmable Gate Array), and a CPLD (Complex Programmable Logic Device). Furthermore, such a digital circuitry may also have a memory storing a program.

[0109] In variations S150, S2150, S3143, S3146, S3147, and S4150, the detection data Dd related to the rainfall state can also be generated independently of the detection data Dd containing the amount of light received data Dr of all detection pixels 46a. In this case, the generation of other detection data Dd containing the amount of light received data Dr of all detection pixels 46a can be performed by the data generation block 120 in S150, S2150, S3143, S3146, S3147, and S4150, or it can be performed by the detection block 100 or the data generation block 120 in S110.

[0110] In a modified example, the process of determining the total internal reflection echo Er within the noise range Lin as noise echo Ern in S4120 of the fourth embodiment can be performed instead of the process of determining the earliest reflected echo Er within the noise range Lin as noise echo Ern in S120 of the first to third embodiments. In this case, in S130 and S2130 of the first to third embodiments, the number of detection pixels 46a that detect at least one noise echo Ern in the current detection cycle Cd, i.e., the number of noise pixels Nn, can be counted.

[0111] In a modified example, the process of determining the total internal reflection echo Er within the effective range LIV as a valid echo Erv based on S4120 of the fourth embodiment can be performed instead of the process of determining the earliest reflected echo Er within the effective range LIV as a valid echo Erv through S120 and S4120 of the first to fourth embodiments. In this case, in S130, S2130, and S4130 of the first to fourth embodiments, the number of detection pixels 46a that detect at least one valid echo Erv in the current detection cycle Cd, i.e., the number of valid pixels Nv, can be counted.

[0112] In a variation, the execution of pixel region 46b in the second embodiment can also be applied to the execution of S130 and S3140 in the third embodiment. In a variation, the execution of pixel region 46b in the second embodiment can also be applied to the execution of S4130, S4140, and S4150 in the fourth embodiment. In a variation, instead of notifying the detection data Dd of the heavy rainfall in response to the increase in noise rate R within the warning range in S3140 and S3143 of the third embodiment, the detection data Dd of the rainfall Q notified by S150 of the first embodiment according to Equation 2 can be executed; or, in addition to notifying the detection data Dd of the heavy rainfall in response to the increase in noise rate R within the warning range in S3140 and S3143 of the third embodiment, the detection data Dd of the rainfall Q notified by S150 of the first embodiment according to Equation 2 can also be executed. In a variation, at least one of the ranges Lin and Liv can be defined as a detection distance L of zero or higher without setting a proximity threshold distance Lt1.

[0113] In a variation, the determination of the noise echo Ern in S4120 of the fourth embodiment can be performed instead of the determination of the noise echo Ern in S120 of the third embodiment. In this case, the counting of the noise determination number Nne in S4130 of the fourth embodiment can be performed instead of the counting of the noise pixel number Nn in S130 of the third embodiment. At the same time, in this case, the monitoring of the noise rate R related to the noise pixel number Nne in S4140 of the fourth embodiment can be performed instead of the monitoring of the noise rate R related to the noise pixel number Nn in S3142 of S3140 of the third embodiment. Furthermore, in this case, instead of notifying the detection data Dd of the heavy rainfall in response to the increase of the noise rate R into the warning range in S3143 of the third embodiment, the detection data Dd of the rainfall Q can be notified in S4150 of the fourth embodiment according to Equation 4. Alternatively, in addition to notifying the detection data Dd of the heavy rainfall in response to the increase of the noise rate R into the warning range in S3143 of the third embodiment, the detection data Dd of the rainfall Q can also be notified in S4150 of the fourth embodiment according to Equation 4.

[0114] In a variation, the control device that executes the control method and control program described above as the control unit 51, and the mobile body 1 that is the object of the optical sensor 10 equipped with the control device, may be, for example, an autonomous robot capable of carrying goods or collecting information through autonomous driving or remote control driving. In another variation, the object of the control device that executes the control method and control program described above as the control unit 51, and the object of the optical sensor 10 equipped with the control device, may be, in addition to the mobile body 1, infrastructure equipment such as a smart pole. Besides the methods described above, the various embodiments and variations described above may also be implemented as the control device of the control unit 51 using a semiconductor device (e.g., a semiconductor chip).

[0115] (Supplementary Explanation) This specification discloses several technical ideas and combinations thereof, as listed below. Furthermore, the symbols in parentheses in this appendix indicate correspondences with specific components described in the previously detailed embodiments, and do not limit the technical scope of this disclosure.

[0116] (Technical Idea 1) A control device having a processor (51b) for controlling an optical sensor (10) that receives, in each detection cycle (Cd) a reflected echo (Er) from a target (Ot) in response to a projected beam (Bp) projected outwards and outputs detection data (Dd), is characterized in that... The processor is configured to perform the following processes: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the noise pixel count (Nn) is monitored relative to the correction pixel count, where the correction pixel count is the number of detected pixels that have detected valid echoes (Erv) determined to be from the total number of detected pixels (ΣN), i.e., the number of valid pixels (Nv). The noise pixel count (Nn) is the number of detected pixels that have detected noise echoes (Ern) determined to be from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

[0117] (Technical Idea 2) A control device having a processor (51b) for controlling an optical sensor (10) that receives, in each detection cycle (Cd) a reflected echo (Er) from a target (Ot) in response to a projected beam (Bp) projected outwards and outputs detection data (Dd), is characterized in that... The processor is configured to perform the following processes: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the ratio of the number of noise echoes (Ern) to the number of corrected pixels is used as the noise rate (R). The number of corrected pixels is the corrected pixel count obtained by subtracting the number of effective echoes (Erv) detected as originating from the reflected echoes determined to originate from the target from the total number of detected pixels (ΣN). The noise echoes (Ern) are the reflected echoes determined to originate from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

[0118] (Technical Idea 3) According to the control device described in technical concept 1 or 2, wherein, The process of monitoring the noise rate includes: Within a noise range (LIn) with respect to the light intensity, where the intensity decreases as the detection distance increases, the reflected echo associated with the detection distance and the light intensity according to the detected pixel is determined as the noise echo; and Within an effective range (LIv) with respect to the light intensity, with the threshold intensity as the lower limit, the reflected echo that is associated with the detection distance and the light intensity according to the detected pixel is determined as the effective echo.

[0119] (Technical Idea 4) According to the control device described in technical concept 3, wherein... The process of monitoring the noise rate includes: The reflected echo, which is the earliest reflected echo of the detected pixel in each detection cycle, along with the detection distance and the light intensity within the noise range, is determined as the noise echo; and The effective echo is determined from the earliest reflected echo of the detected pixel in each detection cycle, the reflected echo of which the detection distance and the light intensity are within the effective range.

[0120] (Technical Idea 5) According to the control device described in technical concept 4, wherein... The process of monitoring the noise rate includes: Among the reflected echoes within the detection distance and the light intensity within the noise range, the noise echo is determined according to the earliest reflected echo with the light timing in each detection cycle, as defined by the detection pixel.

[0121] (Technical Idea 6) According to the control device described in technical concept 4, wherein... The process of monitoring the noise rate includes: The noise echo is defined as all the reflected echoes detected by the detection pixel in the same detection cycle within the detection distance and the light intensity within the noise range.

[0122] (Technical Idea 7) According to any one of technical concepts 3 to 6, the control device wherein... The process of monitoring the noise rate includes: The noise echo and the effective echo are determined based on the reflected echo from the detection distance above the threshold distance (Lt1) corresponding to the position of the detection surface (12a) exposed to the outside in the optical sensor; and The reflected echoes that are less than the threshold distance are excluded from the determination of the noise echoes and the valid echoes.

[0123] (Technical Idea 8) The control device according to any one of technical concepts 1 to 7, wherein, The process of monitoring the noise rate includes: The noise rate is monitored according to a pixel region (46b), which is defined as containing a set number of the detected pixels.

[0124] (Technical Idea 9) The control device according to any one of technical concepts 1 to 8, wherein, The process of generating the detection data includes: The detection data is generated in a manner that notifies the rainfall status by using the rainfall amount related to the noise rate.

[0125] (Technical Idea 10) The control device according to any one of technical concepts 1 to 9, wherein, The process of generating the detection data includes: The detection data is generated in a manner that notifies the rainfall status in response to a situation where the noise rate rises to a warning range that would warn the moving body (1) equipped with the optical sensor.

[0126] (Technical Idea 11) According to the control device described in technical concept 10, wherein, The process of monitoring the noise rate includes: The noise rate is related to the number of effective pixels when the monitoring is reduced to the monitoring range.

[0127] (Technical Idea 12) An optical sensor, which receives a reflected echo (Er) from an object (Ot) in each detection cycle (Cd) of a projected light beam (Bp) directed outwards and outputs detection data (Dd), is characterized by comprising: The control unit (51) is configured to include any one of the control devices described in technical concepts 1 to 11, and generates the detection data; The projection unit (21) projects the projected beam according to the control of the control unit; and The light-receiving part (41) receives the reflected echo according to the control of the control unit.

[0128] Furthermore, the aforementioned technical concepts 1 to 11 can also be grasped through the various technical concepts of methods and procedures.

Claims

1. A control device having a processor (51b) for controlling an optical sensor (10), the optical sensor (10) receiving, in each detection cycle (Cd) a reflected echo (Er) from an object (Ot) for a projected beam (Bp) projected outward and outputting detection data (Dd), the control device being characterized in that, The processor is configured to perform the following processes: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the noise pixel count (Nn) is monitored relative to the correction pixel count, where the correction pixel count is the number of detected pixels that have detected valid echoes (Erv) determined to be from the total number of detected pixels (ΣN), i.e., the number of valid pixels (Nv). The noise pixel count (Nn) is the number of detected pixels that have detected noise echoes (Ern) determined to be from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

2. A control device having a processor (51b) for controlling an optical sensor (10), the optical sensor (10) receiving, in each detection cycle (Cd) a reflected echo (Er) from an object (Ot) for a projected beam (Bp) projected outward and outputting detection data (Dd), the control device being characterized in that, The processor is configured to perform the following processes: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the ratio of the number of noise echoes (Ern) to the number of corrected pixels is used as the noise rate (R). The number of corrected pixels is the corrected pixel count obtained by subtracting the number of effective echoes (Erv) detected as originating from the reflected echoes determined to originate from the target from the total number of detected pixels (ΣN). The noise echoes (Ern) are the reflected echoes determined to originate from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

3. The control device according to claim 1 or 2, characterized in that, The process of monitoring the noise rate includes: Within a noise range (LIn) with respect to the light intensity, where the intensity decreases as the detection distance increases, the reflected echo associated with the detection distance and the light intensity according to the detected pixel is determined as the noise echo; and Within an effective range (LIv) with respect to the light intensity, with the threshold intensity as the lower limit, the reflected echo that is associated with the detection distance and the light intensity according to the detected pixel is determined as the effective echo.

4. The control device according to claim 3, characterized in that, The process of monitoring the noise rate includes: The reflected echo, which is the earliest reflected echo of the detected pixel in each detection cycle, and whose detection distance and light intensity are within the noise range, is determined as the noise echo; as well as The effective echo is determined from the earliest reflected echo of the detected pixel in each detection cycle, the reflected echo of which the detection distance and the light intensity are within the effective range.

5. The control device according to claim 4, characterized in that, The process of monitoring the noise rate includes: Among the reflected echoes within the detection distance and the light intensity within the noise range, the noise echo is determined according to the earliest reflected echo with the light timing in each detection cycle, as defined by the detection pixel.

6. The control device according to claim 4, characterized in that, The process of monitoring the noise rate includes: The noise echo is defined as all the reflected echoes detected by the detection pixel in the same detection cycle within the detection distance and the light intensity within the noise range.

7. The control device according to claim 3, characterized in that, The process of monitoring the noise rate includes: The noise echo and the effective echo are determined based on the reflected echo from the detection distance above the threshold distance (Lt1) corresponding to the position of the detection surface (12a) exposed to the outside in the optical sensor; and The reflected echoes that are less than the threshold distance are excluded from the determination of the noise echoes and the valid echoes.

8. The control device according to claim 1 or 2, characterized in that, The process of monitoring the noise rate includes: The noise rate is monitored according to a pixel region (46b), which is defined as containing a set number of the detected pixels.

9. The control device according to claim 1 or 2, characterized in that, The process of generating the detection data includes: The detection data is generated in a manner that notifies the rainfall status by using the rainfall amount related to the noise rate.

10. The control device according to claim 1 or 2, characterized in that, The process of generating the detection data includes: The detection data is generated in a manner that notifies the rainfall status in response to a situation where the noise rate rises to a warning range that would warn the moving body (1) equipped with the optical sensor.

11. The control device according to claim 10, characterized in that, The process of monitoring the noise rate includes: The noise rate is related to the number of effective pixels when the monitoring is reduced to the monitoring range.

12. An optical sensor that receives, in each detection cycle (Cd) a reflected echo (Er) from an object (Ot) in response to a projected light beam (Bp) projected outwards, and outputs detection data (Dd), characterized in that, have: The control unit (51) is configured to include the control device as described in claim 1 or 2, and generates the detection data; The projection unit (21) projects the projected beam according to the control of the control unit; and The light-receiving part (41) receives the reflected echo according to the control of the control unit.

13. A control method executed by a processor (51b) for controlling an optical sensor (10), the optical sensor (10) receiving a reflected echo (Er) from a target (Ot) for a projected beam (Bp) projected to the outside in each detection cycle (Cd) and outputting detection data (Dd), the control method being characterized in that it comprises: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the noise pixel count (Nn) is monitored relative to the correction pixel count, where the correction pixel count is the number of detected pixels that have detected valid echoes (Erv) determined to be from the total number of detected pixels (ΣN), i.e., the number of valid pixels (Nv). The noise pixel count (Nn) is the number of detected pixels that have detected noise echoes (Ern) determined to be from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

14. A control method executed by a processor (51b) for controlling an optical sensor (10), the optical sensor (10) receiving a reflected echo (Er) from an object (Ot) in each detection cycle (Cd) for a projected beam (Bp) projected to the outside and outputting detection data (Dd), the control method being characterized in that it comprises: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the ratio of the number of noise echoes (Ern) to the number of corrected pixels is used as the noise rate (R). The number of corrected pixels is the corrected pixel count obtained by subtracting the number of effective echoes (Erv) detected as originating from the reflected echoes determined to originate from the target from the total number of detected pixels (ΣN). The noise echoes (Ern) are the reflected echoes determined to originate from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

15. A control program stored in a storage medium (51a) for controlling an optical sensor (10) and containing commands for execution by a processor (51b), the optical sensor (10) receiving, in each detection cycle (Cd) a reflected echo (Er) from an object (Ot) in response to a projected beam (Bp) projected outward and outputting detection data (Dd), the control program being characterized in that, The control program contains commands for performing the following processes: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the noise pixel count (Nn) is monitored relative to the correction pixel count, where the correction pixel count is the number of detected pixels that have detected valid echoes (Erv) determined to be from the total number of detected pixels (ΣN), i.e., the number of valid pixels (Nv). The noise pixel count (Nn) is the number of detected pixels that have detected noise echoes (Ern) determined to be from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

16. A control program stored in a storage medium (51a) for controlling an optical sensor (10) and containing commands for execution by a processor (51b), the optical sensor (10) receiving, in each detection cycle (Cd) a reflected echo (Er) from an object (Ot) in response to a projected beam (Bp) projected outwards and outputting detection data (Dd), the control program being characterized in that, The control program contains commands for performing the following processes: For the detection distance (L) to the target corresponding to the light-receiving timing of the optical sensor receiving the reflected echo, the light intensity (I) of the optical sensor on the reflected echo is obtained in each detection cycle in a manner that each detection pixel (46a) of the detection data is associated with the detection distance (L). In each detection cycle, the ratio of the number of noise echoes (Ern) to the number of corrected pixels is used as the noise rate (R). The number of corrected pixels is the corrected pixel count obtained by subtracting the number of effective echoes (Erv) detected as originating from the reflected echoes determined to originate from the target from the total number of detected pixels (ΣN). The noise echoes (Ern) are the reflected echoes determined to originate from raindrops falling to the outside world. The detection data is generated to inform the outside world of the rainfall status based on the noise rate.

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