Sensor system, mobile object, method of controlling sensor system, control program for sensor system, and computer-readable recording medium on which computer program is recorded

Abstract

The present invention compensates for the visual field of a reflective sensor that has entered an abnormal state. A controller of a sensor system performs sensing with respect to a measurement subject on the basis of a sensing result from a first reflective sensor and a sensing result from a second reflective sensor in a first visual field pattern in which the visual field of the first reflective sensor and the visual field of the second reflective sensor are adjacent to one another in a first direction. If a predetermined modification condition is satisfied, the controller sets the visual field pattern to a second visual field pattern. The second visual field pattern is configured so that, in the first direction, a visual field center orientation and / or a viewing angle of the first reflective sensor is modified, and an overlap region between the modified visual field of the first reflective sensor and the visual field of the second reflective sensor in the first visual field pattern is increased so as to be greater than in the first visual field pattern. The controller performs sensing with respect to the measurement subject on the basis of the sensing result from the first reflective sensor in the second visual field pattern.

Description

Sensor system, mobile body, sensor system control method, sensor system control program, and computer-readable recording medium having computer program recorded thereon

[0001] The technology disclosed in this specification relates to a sensor system.

[0002] With the advancement of AD (Autonomous Driving) and ADAS (Advanced Driver-Assistance Systems), research and development of LiDAR (Light Detection and Ranging) is underway as one of the measurement devices used to grasp the surrounding environment and estimate the vehicle's position while driving. LiDAR is equipped with a reflective sensor. The reflective sensor projects (irradiates) laser light onto a measurement target and receives the reflected light that is reflected back from the measurement target. LiDAR outputs information about the measurement target by measuring the distance to the measurement target based on the time difference between the time when the reflective sensor projects the laser light and the time when it receives the reflected light.

[0003] A sensor system including, for example, a first reflective sensor and a second reflective sensor is disposed in a moving body (e.g., a vehicle). The field of view of the first reflective sensor is different from the field of view of the second reflective sensor. Therefore, if, for example, the second reflective sensor is unable to perform sensing normally due to a malfunction or the like, sensing of the field of view of the second reflective sensor cannot be performed. Therefore, a technique of separately disposing a complementary sensor having a complementary field of view has been known. The complementary sensor has a field of view that complements the field of view of the second reflective sensor. Therefore, even if the second reflective sensor fails or the like, the field of view of the second reflective sensor is complemented by the complementary sensor (see, for example, Patent Document 1).

[0004] Special Publication No. 2022-512092

[0005] The conventional sensor system described above requires the provision of a separate complementary sensor, leaving room for improvement. Note that this issue is not limited to sensor systems installed on moving objects, but is a common issue in sensor systems equipped with multiple reflective sensors with different fields of view.

[0006] This specification discloses a technique that can solve the above-mentioned problems.

[0007] The technology disclosed in this specification can be realized, for example, in the following forms.

[0008] (1) A sensor system disclosed in this specification includes a first reflective sensor, a second reflective sensor, and a controller. The controller senses a measurement target based on detection results from the first reflective sensor and the second reflective sensor in a first field of view pattern in which the fields of view of the first reflective sensor and the second reflective sensor are adjacent to each other in a first direction, and sets the field of view pattern to a second field of view pattern when a predetermined change condition is satisfied. The second field of view pattern is a pattern in which at least one of the orientation of the field of view center and the field of view angle of the first reflective sensor in the first direction is changed, and an overlap area between the changed field of view of the first reflective sensor and the field of view of the second reflective sensor in the first field of view pattern is increased compared to the first field of view pattern. The controller senses the measurement target based on detection results from the first reflective sensor in the second field of view pattern. According to this sensor system, when a predetermined change condition is satisfied, at least one of the direction of the center of the field of view and the field of view angle of the first reflective sensor can be changed to compensate for the field of view of the second reflective sensor.

[0009] (2) In the sensor system, the predetermined change condition may include the controller detecting an abnormality in the second reflective sensor. According to this sensor system, when an abnormality occurs in the second reflective sensor, at least one of the direction of the center of the field of view and the field of view angle of the first reflective sensor can be changed to compensate for the field of view of the second reflective sensor.

[0010] (3) In the sensor system, the controller may be configured to widen the field of view angle of the first reflective sensor relative to the first field of view pattern and set the second field of view pattern, and the angular resolution of the first reflective sensor in the first field of view pattern may be higher than the angular resolution of the first reflective sensor in the second field of view pattern. This sensor system can improve the sensing accuracy of the first reflective sensor in the first field of view pattern, for example, compared to when the angular resolution of the first reflective sensor in the first field of view pattern is the same as when the second field of view pattern is used.

[0011] (4) The sensor system may further include a third reflective sensor located on the opposite side of the first reflective sensor from the second reflective sensor in the first direction, and the controller may change the orientation of the center of the field of view of the first reflective sensor to set the second field of view pattern, and change at least one of the orientation of the center of the field of view and the field of view angle of the third reflective sensor to increase the overlap area between the changed field of view of the third reflective sensor and the field of view of the first reflective sensor in the first field of view pattern compared to the first field of view pattern. This sensor system can supplement the field of view of the first reflective sensor by changing at least one of the orientation of the center of the field of view and the field of view angle of the third reflective sensor in the second field of view pattern.

[0012] The technology disclosed in this specification can be realized in various forms, such as a sensor system, a mobile object, a control method for a sensor system, a control program for a sensor system, and a computer-readable recording medium on which a computer program is recorded.

[0013] Schematic diagram showing the basic pattern of a plurality of reflective sensors 10 provided on a vehicle 1 in an embodiment. Block diagram showing the general configuration of the reflective sensor 10. Schematic diagram showing the configuration for changing the orientation of the center of the field of view of the reflective sensor 10. Schematic diagram showing the configuration for changing the field of view angle of the reflective sensor 10. Descriptive diagram showing the relationship between the field of view angle and the measurement period. Flowchart showing the surroundings monitoring process. Schematic diagram showing the change pattern of the plurality of reflective sensors 10.

[0014] A. Embodiments: A-1. Configuration of Vehicle 1: FIG. 1 is a schematic diagram showing the basic pattern of multiple reflective sensors 10 provided on a vehicle 1 in this embodiment. FIG. 1 and FIG. 7, which will be described later, show arrows representing each direction based on the position of the vehicle 1. More specifically, each figure shows arrows representing the front (FRONT), rear (REAR), left (LEFT), and right (RIGHT), respectively. The front-to-rear direction and the left-to-right direction are directions that are perpendicular to each other. The vehicle 1 is an example of a moving body.

[0015] 1, the vehicle 1 is a four-wheeled automobile. The vehicle 1 is equipped with a sensor system 11. The sensor system 11 includes a plurality of reflective sensors 10 and a controller 60 (see FIG. 2, which will be described later).

[0016] The multiple reflective sensors 10 include a front center sensor 10A, a front right sensor 10B, a front left sensor 10C, a rear center sensor 10D, a rear right sensor 10E, and a rear left sensor 10F. FIG. 1 shows the fields of view (FOVs) of each of the reflective sensors 10A to 10F in the basic pattern (the sector-shaped shaded areas in FIG. 1). Of the multiple reflective sensors 10, three reflective sensors 10 whose fields of view V are adjacent to each other are examples of a first reflective sensor, a second reflective sensor, and a third reflective sensor. The basic pattern is an example of a first field of view pattern.

[0017] The front center sensor 10A is disposed in the center of the front end of the vehicle 1. For example, the front center sensor 10A is disposed between the right front lamp 2 and the left front lamp 2. The field of view Va1 of the front center sensor 10A in the basic pattern is the front, front side of the vehicle 1. The front light sensor 10B is disposed on the right side of the front end of the vehicle 1. For example, the front light sensor 10B may be disposed near the right front lamp 2 or may be incorporated into the right front lamp 2. The field of view Vb1 of the front light sensor 10B in the basic pattern is the front, right side of the vehicle 1. The front left sensor 10C is disposed on the left side of the front end of the vehicle 1. For example, the front left sensor 10C may be disposed near the left front lamp 2 or may be incorporated into the left front lamp 2. The field of view Vc1 of the front left sensor 10C in the basic pattern is the front, left side of the vehicle 1.

[0018] The rear center sensor 10D is disposed in the center of the rear end of the vehicle 1. For example, the rear center sensor 10D is disposed between the right rear lamp 4 and the left rear lamp 4. The field of view Vd1 of the rear center sensor 10D in the basic pattern is rear of the vehicle 1. The rear light sensor 10E is disposed on the right side of the rear end of the vehicle 1. For example, the rear light sensor 10E may be disposed near the right rear lamp 4 or may be built into the right rear lamp 4. The field of view Ve1 of the rear light sensor 10E in the basic pattern is the right side of the vehicle 1. The rear left sensor 10F is disposed on the left side of the rear end of the vehicle 1. For example, the rear left sensor 10F may be disposed near the left rear lamp 4 or may be built into the left rear lamp 4. The field of view Vf1 of the rear left sensor 10F in the basic pattern is the left side of the vehicle 1.

[0019] A-2. Configuration of the reflective sensor 10: Fig. 2 is a block diagram showing a schematic configuration of the reflective sensor 10. Fig. 2 shows one reflective sensor 10 of the sensor system 11 and a controller 60. Each of the multiple reflective sensors 10 is communicatively connected to the controller 60.

[0020] 2, the reflective sensor 10 functions as a LiDAR and includes a projector 20 that irradiates a measurement object W with emitted light L1 (e.g., a light beam (laser light)) and a receiver 30 that receives reflected light L2 (return light) that is generated when the emitted light L1 is reflected by the measurement object W and returns to the measurement object W. The reflective sensor 10 measures the difference between the timing at which the projector 20 emits the emitted light L1 and the timing at which the receiver 30 receives the reflected light L2 (time of flight of the laser light, hereinafter referred to as "TOF" (Time of Flight)) to acquire information about the measurement object W.

[0021] The reflective sensor 10 assists in detecting objects such as people and other vehicles while the vehicle 1 is traveling, and provides various information to other devices and users that is useful for ensuring the safety of the vehicle driver and those around the vehicle, and for reducing damage to surrounding objects while the vehicle is being driven.

[0022] The light projector 20 includes a light source 22 , a light projecting optical system 24 , a light projecting control device 26 , and a current source 28 .

[0023] The light source 22 includes a light-emitting source having one or more light-emitting elements (not shown), or one or more light-emitting element arrays (e.g., light-emitting elements arranged linearly (one-dimensionally) or planarly (two-dimensionally)). The light-emitting element may be, for example, a laser diode, a surface-emitting laser light-emitting element (e.g., a VCSEL (Vertical Cavity Surface Emitting Laser), hereinafter referred to as a "surface-emitting element"), or a surface-emitting element array (e.g., a VCSEL array) in which a plurality of surface-emitting elements are arranged one-dimensionally or two-dimensionally on a substrate (e.g., a semiconductor substrate, a ceramic substrate, etc.).

[0024] The current source 28 supplies a current corresponding to a control signal input from the light projection control device 26 to the light emitting element that constitutes the light source 22. The current source 28 supplies, for example, a periodic square wave current to the light emitting element for turning on and off the current flowing through the light emitting element.

[0025] The light-projection control device 26 generates a control signal for the current source 28 and inputs it to the current source 28, thereby controlling the current (drive current) supplied to the light-emitting element from the current source 28. The light-projection control device 26 inputs a signal indicating the timing at which the light-emitting element emits light (the timing at which the light-emitting element emits light; hereinafter referred to as "light-projection timing") to the TOF measurement device 40. The light-projection control device 26 periodically controls the on / off of a current flowing through the light-emitting element, for example, to cause the light-emitting element to periodically emit light.

[0026] The light projection optical system 24 adjusts the light distribution of the output light L1 by, for example, applying an optical effect (such as refraction, scattering, or diffraction) to the light emitted by the light source 22. The light projection optical system 24 is configured using optical components such as various lenses, such as collimating lenses, and reflecting mirrors (mirrors).

[0027] The light receiver 30 includes a light receiving section 32 and a light receiving optical system 34 .

[0028] The light receiving optical system 34 collects reflected light L2, which is light L1 emitted from the projector 20 and reflected by the measurement target W or the like, onto the light receiving unit 32. The light receiving optical system 34 is configured using optical components such as various lenses, such as a collecting lens, various filters, such as a wavelength filter, and a reflecting mirror (mirror).

[0029] The light receiving unit 32 has a plurality of light receiving elements. The light receiving elements are, for example, photodiodes, SPADs (Single Photon Avalanche Diodes), balanced photodetectors, etc. The light receiving unit 32 performs photoelectric conversion on the reflected light L2 incident from the light receiving optical system 34 to generate a light receiving signal with a current level or voltage level corresponding to the intensity of the reflected light L2. The light receiving unit 32 inputs, to the TOF measurement device 40, a signal indicating the timing at which the light receiving elements constituting the light receiving unit 32 receive the reflected light L2 (hereinafter referred to as "light receiving timing"), and the light receiving signal generated by the light receiving elements.

[0030] The reflective sensor 10 further includes a TOF measurement device 40 , a control circuit 42 , and a communication I / F (Interface) 50 .

[0031] The TOF measurement device 40 calculates the TOF based on a signal indicating the light projection timing input from the light projection control device 26 and a signal indicating the light reception timing input from the light receiving unit 32. The TOF measurement device 40 has, for example, a time measurement IC (Integrated Circuit) equipped with a TDC (Time to Digital Converter) circuit. The TOF measurement device 40 inputs the calculated TOF and the light reception signal input from the light receiving unit 32 to the control circuit 42.

[0032] The control circuit 42 has a processor (such as a CPU (Central Processing Unit), MPU (Micro Processing Unit), ASIC (Application Specific Integrated Circuit), FPGA (Field Programmable Gate Array), DSP (Digital Signal Processor)). Based on the light receiving signal and TOF input from the TOF measurement device 40, the control circuit 42 generates information used for various measurements such as detection of the measurement object W and distance measurement. The information includes, for example, a histogram used in time-correlated single photon counting, distances to each point on the measurement target W, a point cloud (point cloud information), etc. The control circuit 42 also controls the light-projection control device 26 and the light-receiving unit 32. The control circuit 42 controls the light-projection timing and light-receiving timing described above, for example, by controlling the light-projection control device 26 and the light-receiving unit 32, so as to speed up or optimize the processing involved in generating the histogram. The information generated by the control circuit 42 is provided (transmitted) via the communication I / F 50 to the controller 60 and devices that use the information (hereinafter referred to as "various use devices").

[0033] Various utilization devices perform, for example, the creation of environmental maps using point clouds, and self-location estimation (SLAM (Simultaneous Localization and Mapping)) using scan matching algorithms (NDT (Normal Distributions Transform), ICP (Iterative Closest Point), etc.).

[0034] The controller 60 is configured using, for example, a CPU, a multi-core CPU, or a programmable device (for example, an FPGA (Field Programmable Gate Array) or a PLD (Programmable Logic Device)). The controller 60 controls the operations of the multiple reflective sensors 10.

[0035] The controller 60 individually determines whether each of the multiple reflective sensors 10 is in an abnormal state. An abnormal state of the reflective sensor 10 refers to a state in which the reflective sensor 10 cannot perform sensing normally, and examples of such states include the following: The reflective sensor 10 stops operating due to a malfunction or a broken wire; The light emission intensity of the light source 22 of the projector 20 exceeds a specified value, causing a feel-safe function to stop the reflective sensor 10 from sensing (light emission and reception); The reflective sensor 10 operates normally, but foreign matter such as dust adheres to or is damaged in the light-projecting optical system 24 or the light-receiving optical system 34, preventing normal sensing (such as a restricted field of view). The controller 60 can determine whether the above-mentioned abnormal state exists by detecting that the amount of light received by the light-receiving unit 32 is below a predetermined level or by receiving a detection signal from a central control device (not shown) of the vehicle 1.

[0036] The controller 60 includes a storage device. The storage device is configured, for example, with a ROM, RAM, HDD (hard disk drive), or SSD (solid-state drive). The storage device stores various programs and data, and is used as a work area and data storage area when executing various processes. For example, the storage device stores a computer program for executing the measurement process and the surroundings monitoring process described below. This computer program is provided in a state stored on a computer-readable recording medium (not shown), such as a CD-ROM, DVD-ROM, or USB memory, or is provided in a state that can be obtained from an external device via a communication interface (not shown), and is stored in the storage device in a state that is operable on the sensor system 11.

[0037] A-3. Configuration for Changing the Orientation of the Field of View Center O and the Field of View Angle of the Reflective Sensor 10: FIG. 3 is a schematic diagram showing a configuration for changing the orientation of the field of view center of the reflective sensor 10. As shown in FIG. 3, the reflective sensor 10 is installed on the vehicle 1 so as to be rotatable about an axis Q along the vertical direction. Therefore, when the reflective sensor 10 is rotated, the field of view of the reflective sensor 10 is changed from a first field of view V1 to a second field of view V2. The first field of view V1 and the second field of view V2 have the same field of view angle θ but have different orientations of the field of view center O. In other words, the reflective sensor 10 is configured so that the orientation of the field of view center O can be changed without changing the field of view angle θ of the reflective sensor 10.

[0038] FIG. 4 is a schematic diagram showing a configuration for changing the field of view of the reflective sensor 10. As shown in FIG. 4, the reflective sensor 10 is configured to be able to change the field of view angle θ (width of the horizontal field of view). In FIG. 4, the field of view of the reflective sensor 10 is changed from a third field of view V3 to a fourth field of view V4. The third field of view V3 and the fourth field of view V4 have the same orientation of the field of view center O but different field of view angles θ (θ1<θ2). In other words, the reflective sensor 10 is configured to be able to change the field of view angle θ of the reflective sensor 10 without changing the orientation of the field of view center O. For example, the control circuit 42 can change the field of view angle θ of the reflective sensor 10 by changing at least one of the light projection range of the light emitter 20 and the light reception range of the light receiver 30.

[0039] 5 is an explanatory diagram showing the relationship between the field of view V and the measurement period. The upper part of Fig. 5 shows a virtual third field of view V3, and the lower part shows a virtual fourth field of view V4. The receiver 30 (light receiving unit 32) has a plurality of light receiving elements arranged two-dimensionally, and each of the plurality of light receiving elements corresponds to a measurement point P in the third field of view V3.

[0040] The horizontal field of view angle θ1 of the third field of view V3 is narrower than the horizontal field of view angle θ2 of the fourth field of view V4 (see FIG. 4). Therefore, as shown in FIG. 5, the horizontal field of view of the third field of view V3 is narrower than the horizontal field of view of the fourth field of view V4. The angular resolution of the reflective sensor 10 in the third field of view V3 is higher than the angular resolution of the reflective sensor 10 in the fourth field of view V4. In other words, the distance R1 between adjacent measurement points P in the third field of view V3 (hereinafter referred to as the "measurement-to-measurement distance") is narrower than the measurement-to-measurement distance R2 in the fourth field of view V4.

[0041] The number of measurement points P in the horizontal field of view of the third field of view V3 is the same as the number of measurement points P in the horizontal field of view of the fourth field of view V4. Therefore, the measurement period of the horizontal field of view of the third field of view V3 in one frame is the same as the measurement period of the horizontal field of view of the fourth field of view V4 in one frame. In other words, although the third field of view V3 has a narrower field of view angle than the fourth field of view V4, it is possible to perform high-precision sensing with high angular resolution while maintaining the measurement period. Note that the third field of view V3 and the fourth field of view V4 have the same vertical field of view.

[0042] A-4. Surroundings Monitoring Process: FIG. 6 is a flowchart showing the surroundings monitoring process. The surroundings monitoring process is a process in which multiple reflective sensors 10 are used to sense objects and the like around the vehicle 1. For example, when the controller 60 receives an instruction to start measurement from a device being used, the controller 60 executes the surroundings monitoring process shown in FIG. 6. The controller 60 determines whether the sensing timing has arrived (S110). The sensing timing is the timing that triggers the start of measurement processing for each reflective sensor 10 in one frame unit. Sensing (measurement processing) includes, for example, detecting the measurement target, measuring the distance to the measurement target, measuring the shape of the measurement target, and the like. If the controller 60 determines that the sensing timing has not arrived (S110: NO), it waits.

[0043] When the controller 60 determines that the sensing timing has arrived (S110: YES), it sets the field of view patterns of the multiple reflective sensors 10 to a reference pattern and causes each of the multiple reflective sensors 10 to perform sensing (S120). The reference pattern is the field of view pattern shown in FIG. 1. The reference pattern is an example of a first field of view pattern. The reference pattern is a pattern in which sensing is performed all around the vehicle 1 using six reflective sensors 10 (sensors 10A to 10F), and the fields of view of two adjacent reflective sensors 10 barely overlap each other.

[0044] The controller 60 determines whether or not there is an abnormal reflective sensor 10 (hereinafter, sometimes referred to as an "abnormal sensor") among the multiple reflective sensors 10 (S130). The controller 60 determines whether or not there is an abnormal sensor based on, for example, the light reception results of each reflective sensor 10 in the sensing executed immediately before, a notification signal from an external device, etc. If the controller 60 determines that there is no abnormal sensor (S130: NO), it returns to S110, and when the next sensing timing arrives (S110: YES), it causes each of the multiple reflective sensors 10 to execute sensing while maintaining the reference pattern (S120).

[0045] When the controller 60 determines that there is an abnormal sensor (S130: YES), it changes the field of view patterns of the multiple reflective sensors 10 from the reference pattern to a modified pattern (S140). The modified pattern is an example of a second field of view pattern. The modified pattern is a pattern in which at least one of the orientation of the field of view center and the field of view angle of a reflective sensor 10 in a normal state (hereinafter sometimes referred to as a "normal sensor") is changed relative to the reference pattern, thereby increasing the overlap area between the field of view of the normal sensor after the change and the field of view of the abnormal sensor in the reference pattern. By setting the modified pattern, the field of view missing due to the abnormal sensor is complemented.

[0046] 7 is a schematic diagram showing change patterns for multiple reflective sensors 10. Fig. 7 illustrates an example of a change pattern when the rear center sensor 10D becomes an abnormal sensor. In the reference pattern, the reflective sensors 10 whose fields of view are adjacent to the rear center sensor 10D in the horizontal direction are the rear right sensor 10E and the rear left sensor 10F.

[0047] 7 , in the modified pattern, the orientation of the field of view center O of the rear light sensor 10E is changed relative to the reference pattern, thereby increasing the overlapping area between the modified field of view Ve2 of the rear light sensor 10E and the field of view Vd1 of the rear center sensor 10D (the abnormal sensor). In other words, the orientation of the field of view center O of the rear light sensor 10E is changed toward the field of view Vd1 of the rear center sensor 10D, so that the modified field of view Ve2 of the rear light sensor 10E complements a portion of the field of view Vd1 of the rear center sensor 10D. In the modified pattern, the orientation of the field of view center O of the rear left sensor 10F is changed relative to the reference pattern, thereby increasing the overlapping area between the modified field of view Vf2 of the rear left sensor 10F and the field of view Vd1 of the rear center sensor 10D (the abnormal sensor). In other words, by changing the orientation of the field of view center O of the rear left sensor 10F toward the field of view Vd1 of the rear center sensor 10D, the changed field of view Ve2 of the rear left sensor 10F complements a portion of the field of view Vd1 of the rear center sensor 10D.

[0048] In the modified pattern, the orientation of the field of view center O of the front light sensor 10B is changed relative to the reference pattern, thereby increasing the overlapping area between the modified field of view Vb2 of the front light sensor 10B and the pre-change field of view Ve1 of the rear light sensor 10E. In other words, the orientation of the field of view center O of the front light sensor 10B is changed toward the field of view Ve1 of the rear light sensor 10E, so that the modified field of view Vb2 of the front light sensor 10B complements a portion of the pre-change field of view Ve1 of the rear light sensor 10E. In the modified pattern, the orientation of the field of view center O of the front left sensor 10C is changed relative to the reference pattern, thereby increasing the overlapping area between the modified field of view Vc2 of the front left sensor 10C and the pre-change field of view Vf1 of the rear left sensor 10F. In other words, by changing the orientation of the field of view center O of the front left sensor 10C toward the field of view Vf1 of the rear left sensor 10F, the field of view Vf2 after the change of the rear left sensor 10F complements a portion of the field of view Vf1 before the change of the rear left sensor 10F.

[0049] In the modified pattern, the field of view angle θ of the front center sensor 10A is wider than that of the reference pattern, which increases the overlapping area between the modified field of view Va2 of the front center sensor 10A and the pre-modified field of view Vb1 of the front right sensor 10B. In other words, the field of view of the front center sensor 10A has expanded toward the field of view Vb1 of the front right sensor 10B, so the modified field of view Va2 of the front center sensor 10A partially complements the pre-modified field of view Vb1 of the front right sensor 10B. In the modified pattern, the field of view angle θ of the front center sensor 10A is wider than that of the reference pattern, which increases the overlapping area between the modified field of view Va2 of the front center sensor 10A and the pre-modified field of view Vc1 of the front left sensor 10C. In other words, the field of view of the front center sensor 10A has expanded toward the field of view Vc1 of the front left sensor 10C, so the modified field of view Va2 of the front center sensor 10A partially complements the pre-modified field of view Vc1 of the front left sensor 10C.

[0050] As described above, in the change pattern, by changing at least one of the orientation of the field of view center O of the normal sensor and the field of view angle θ, the field of view lost by the abnormal sensor is complemented and sensing (field of view) is maintained around the entire circumference of the vehicle 1.

[0051] In the modified pattern, the viewing angle θ of the front center sensor 10A is wider than in the reference pattern, and the measurement period is maintained.

[0052] B. Modifications: The technology disclosed in this specification is not limited to the above-described embodiment, and can be modified in various forms without departing from the spirit of the invention. For example, the following modifications are also possible.

[0053] The configurations of the vehicle 1, sensor system 11, and reflective sensor 10 in the above embodiment are merely examples and can be modified in various ways. For example, the mobile object may be a vehicle other than a four-wheeled vehicle (such as a two-wheeled vehicle), or may be a mobile object other than a vehicle (such as a mobile robot). The sensor system 11 is not limited to a mobile object, and may be fixedly installed in a predetermined location. The sensor system 11 may be configured to include at least two reflective sensors.

[0054] In the above embodiment, in the configuration shown in FIG. 4 , at least one of the light projection range of the projector 20 and the light reception range of the receiver 30 may be changed within the range of the maximum field of view of the reflective sensor 10, thereby changing at least one of the field of view angle θ and the orientation of the field of view center O of the reflective sensor 10. Furthermore, in the above embodiment, the first direction is the horizontal direction, but this is not limited thereto and may be a direction other than the horizontal direction (e.g., the vertical direction or a direction inclined relative to the vertical direction). For example, in a sensor system in which the field of view of a first reflective sensor and the field of view of a second reflective sensor are adjacent to each other in the vertical (perpendicular) direction, at least one of the orientation of the vertical field of view center and the vertical field of view angle of the first reflective sensor may be changed. Furthermore, both the orientation of the vertical field of view center and the vertical field of view angle of the first reflective sensor may be changed.

[0055] In the surroundings monitoring process of the above embodiment, the change condition is exemplified as the detection of an abnormal sensor, but it is not limited to this and may be, for example, when an input operation by the driver or a change instruction is received from a control device on the vehicle side. In the above embodiment, in the change pattern, the measurement period of the front center sensor 10A may be lengthened relative to the reference pattern to maintain the angular resolution.

[0056] This international application claims priority based on Japanese Patent Application No. 2024-021650, filed on February 16, 2024, the entire contents of which are incorporated herein by reference.

[0057] The above descriptions of specific embodiments of the present invention have been presented for purposes of illustration. They are not intended to be exhaustive or to limit the invention to the precise forms described. Numerous modifications and variations will be apparent to those skilled in the art in light of the above description.

[0058] 1: Vehicle 10: Reflective sensor 10A (10A to 10F): Front center sensor 11: Sensor system 20: Emitter 22: Light source 24: Emitter optical system 26: Emitter control device 28: Current source 30: Receiver 32: Light receiving section 34: Light receiving optical system 40: TOF measuring device 42: Control circuit 50: Communication I / F 60: Controller CPU: Multi-core IC: Time measurement L1: Emitted light L2: Reflected light O: Center of field of view P: Measurement point Q: Axis along W: Measurement object

Claims

1. A sensor system comprising a first reflective sensor, a second reflective sensor, and a controller, wherein the controller: senses a measurement object based on the detection results of the first reflective sensor and the detection results of the second reflective sensor in a first field of view pattern in which the fields of view of the first reflective sensor and the fields of view of the second reflective sensor are adjacent to each other in a first direction; when a predetermined change condition is satisfied, changes at least one of the orientation of the field of view center and the field of view angle of the first reflective sensor in the first direction, and sets an overlapping area between the changed field of view of the first reflective sensor and the field of view of the second reflective sensor in the first field of view pattern to a second field of view pattern that is larger than the first field of view pattern; and senses the measurement object based on the detection results of the first reflective sensor in the second field of view pattern.

2. A sensor system according to claim 1, wherein the predetermined change condition includes the controller detecting an abnormality in the second reflective sensor.

3. A sensor system as described in claim 1, wherein the controller widens the field of view angle of the first reflective sensor relative to the first field of view pattern and sets it to the second field of view pattern, and the angular resolution of the first reflective sensor in the first field of view pattern is higher than the angular resolution of the first reflective sensor in the second field of view pattern.

4. A sensor system as described in claim 1, further comprising a third reflective sensor located on the opposite side of the first reflective sensor from the second reflective sensor in the first direction, wherein the controller changes the orientation of the center of the field of view of the first reflective sensor to set it to the second field of view pattern, and changes at least one of the orientation of the center of the field of view and the field of view angle of the third reflective sensor, thereby increasing the overlap area between the changed field of view of the third reflective sensor and the field of view of the first reflective sensor in the first field of view pattern compared to the first field of view pattern.

5. A moving body comprising the sensor system according to any one of claims 1 to 4, wherein the first reflective sensor and the second reflective sensor are arranged on the front side of the moving body.

6. A control method for a sensor system comprising a first reflective sensor and a second reflective sensor, wherein sensing of a measurement object is performed based on the detection results of the first reflective sensor and the detection results of the second reflective sensor in a first field of view pattern in which the fields of view of the first reflective sensor and the second reflective sensor are adjacent to each other in a first direction, and when a predetermined change condition is satisfied, at least one of the orientation of the field of view center and the field of view angle of the first reflective sensor in the first direction is changed, and an overlapping area between the changed field of view of the first reflective sensor and the field of view of the second reflective sensor in the first field of view pattern is set to a second field of view pattern that is larger than the first field of view pattern, and sensing of the measurement object is performed based on the detection results of the first reflective sensor in the second field of view pattern.

7. A control program for a sensor system that causes a controller of a sensor system comprising a first reflective sensor and a second reflective sensor to perform sensing of a measurement object based on the detection results of the first reflective sensor and the detection results of the second reflective sensor in a first field of view pattern in which the fields of view of the first reflective sensor and the second reflective sensor are adjacent to each other in a first direction, and when a predetermined change condition is satisfied, to change at least one of the orientation of the field of view center and the field of view angle of the first reflective sensor in the first direction, and set the overlap area between the changed field of view of the first reflective sensor and the field of view of the second reflective sensor in the first field of view pattern to a second field of view pattern that is larger than the first field of view pattern, and to perform sensing of the measurement object based on the detection results of the first reflective sensor in the second field of view pattern.

8. A computer-readable recording medium having recorded thereon a computer program for controlling a sensor system comprising a first reflective sensor and a second reflective sensor, the computer program causing the sensor system to: sense a measurement object based on the detection results of the first reflective sensor and the detection results of the second reflective sensor in a first field of view pattern in which the fields of view of the first reflective sensor and the second reflective sensor are adjacent to each other in a first direction; change at least one of the orientation of the field of view center and the field of view angle of the first reflective sensor in the first direction when a predetermined change condition is satisfied, and set a second field of view pattern in which the overlapping area between the changed field of view of the first reflective sensor and the field of view of the second reflective sensor in the first field of view pattern is larger than the first field of view pattern; and sense the measurement object in the second field of view pattern based on the detection results of the first reflective sensor.

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