Control device, optical sensor, control method, and control program

Abstract

In control involving a processor to control an optical sensor that outputs detection data obtained by detecting the distance to a target by receiving a reflected beam from the target in response to a projected light beam projected to a detection area, the processor is configured to: monitor a fluctuation range (δM) of a correction parameter (Mp) specifying the temperature dependency of a distance correction amount (ΔL) in a correction model (M) for correcting the distance detection data depending on the temperature, to thereby update a stored parameter (Mpm) stored in memory as the correction parameter if the fluctuation range (δM) is outside an allowable range; and correct the detection data by the correction amount (ΔL) corresponding to the temperature each time the distance is detected, in accordance with the correction model (M) provided in accordance with the latest stored parameter (Mpm).

Description

Control device, optical sensor, control method, and control program CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Patent Application No. 2023-156249 filed in Japan on September 21, 2023, and Patent Application No. 2023-219876 filed in Japan on December 26, 2023, and the contents of the base applications are incorporated by reference in their entirety.

[0002] The present disclosure relates to techniques for controlling optical sensors.

[0003] The optical sensor disclosed in Patent Document 1 is controlled to detect the distance to the target by receiving a beam reflected from the target in response to a beam projected onto a detection area. As one type of such control technology, Patent Document 1 proposes correcting a measurement time equivalent to the detection distance by using a delay time caused by processing in a control unit as a correction amount.

[0004] Patent No. 6449545

[0005] However, in the optical sensor disclosed in Patent Document 1, the delay time corresponding to the temperature detected by another optical sensor on the same moving object is extracted according to a pre-prepared map. However, errors in the measurement time equivalent to the detection distance are caused not only by the delay time due to processing in the control unit, but also by, for example, aging of the sensor elements that make up the optical sensor and resulting abnormalities. Therefore, with the optical sensor disclosed in Patent Document 1, there is a concern that even if the error changes over time, the detection accuracy of the distance corresponding to the measurement time, which is always corrected according to a constant map, will decrease.

[0006] An object of the present disclosure is to provide a control device that ensures the accuracy of distance detection by an optical sensor. Another object of the present disclosure is to provide an optical sensor equipped with a control device that ensures the accuracy of distance detection. Yet another object of the present disclosure is to provide a control method that ensures the accuracy of distance detection by an optical sensor. Yet another object of the present disclosure is to provide a control program that ensures the accuracy of distance detection by an optical sensor.

[0007] The technical means of the present disclosure for solving the problems will be described below.

[0008] A first aspect of the present disclosure is a control device having a processor for controlling an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, wherein the processor is configured to: monitor the fluctuation range of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting the distance detection data depending on temperature; update a memory parameter stored in a storage medium as a correction parameter when the fluctuation range falls outside an allowable range; and correct the detection data with a correction amount that matches the temperature for each distance detection according to the correction model given according to the latest stored parameter.

[0009] A second aspect of the present disclosure is a control method executed by a processor to control an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, the control method including: monitoring the fluctuation range of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting distance detection data depending on temperature, and updating a stored parameter stored in a storage medium as a correction parameter when the fluctuation range falls outside an allowable range; and correcting the detection data with a correction amount that matches the temperature for each distance detection according to the correction model given according to the latest stored parameter.

[0010] A third aspect of the present disclosure is a control program stored in a storage medium for controlling an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, and includes instructions for causing a processor to execute the control, wherein the control program includes instructions for: monitoring the fluctuation range of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting distance detection data depending on temperature, and updating the stored parameter stored in the storage medium as a correction parameter when the fluctuation range falls outside an allowable range; and correcting the detection data with a correction amount that matches the temperature for each distance detection in accordance with the correction model given according to the latest stored parameter.

[0011] According to the first to third aspects, in a correction model for correcting distance detection data depending on temperature, the fluctuation range of a correction parameter that defines the temperature dependency of the distance correction amount is monitored. If the fluctuation range of the correction parameter falls outside the allowable range, the stored parameters stored in the storage medium as the correction parameters are updated. Therefore, by correcting the detection data using a correction amount that matches the temperature for each distance detection according to the correction model provided according to the latest stored parameters, it is possible to output detection data that ensures distance detection accuracy regardless of the passage of time.

[0012] A fourth aspect of the present disclosure is a control device having a processor for controlling an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, wherein the processor is configured to monitor a failure indicator that correlates with the range of fluctuation of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting the distance detection data depending on temperature, and to output failure notification information that notifies the user of the failure state when the failure indicator falls outside an acceptable range.

[0013] A fifth aspect of the present disclosure is a control method executed by a processor to control an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, the method including: monitoring a failure indicator that correlates with the range of fluctuation of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting the distance detection data depending on temperature; and outputting failure notification information that notifies the user of the failure state when the failure indicator falls outside the acceptable range of the optical sensor.

[0014] A sixth aspect of the present disclosure is a control program stored in a storage medium for controlling an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, and includes instructions for causing a processor to execute the control, the control program including instructions for executing the following: monitoring a failure indicator that correlates with the fluctuation range of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting distance detection data depending on temperature; and outputting failure notification information that notifies the user of the failure state when the failure indicator falls outside the allowable range, when the state of the optical sensor is in a failure state.

[0015] According to the fourth to sixth aspects, in a correction model for correcting distance detection data depending on temperature, a failure indicator correlated with the fluctuation range of a correction parameter that defines the temperature dependency of the distance correction amount is monitored. Therefore, when the failure indicator falls outside the allowable range, the optical sensor is deemed to be in a fault state, and failure notification information notifying the fault state is output. In this way, since the optical sensor can accurately notify the fault state through the failure notification information, conversely, under normal conditions without such notification, the detection data is corrected according to the temperature at each distance detection in accordance with the correction model, enabling the output of detection data with ensured distance detection accuracy.

[0016] A seventh aspect of the present disclosure is a control device having a processor for controlling an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, wherein the processor is configured to: monitor a failure indicator that correlates with the fluctuation range of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting the distance detection data depending on temperature; and treat the state of the optical sensor where the failure indicator is outside the allowable range as a failure state, and adjust the control parameter for controlling the optical sensor to recover from the failure state.

[0017] An eighth aspect of the present disclosure is a control method executed by a processor to control an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, the method including: monitoring a failure indicator that correlates with the range of fluctuation of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting the distance detection data depending on temperature; and determining that the state of the optical sensor in which the failure indicator is outside the acceptable range is in a failure state, and adjusting the control parameter for controlling the optical sensor to recover from the failure state.

[0018] A ninth aspect of the present disclosure is a control program stored in a storage medium for controlling an optical sensor that receives a reflected beam from a target in response to a projected beam onto a detection area and outputs detection data that detects the distance to the target, and includes instructions for causing a processor to execute the control, the control program including instructions for executing the following: monitoring a failure indicator that correlates with the fluctuation range of a correction parameter that specifies the temperature dependency of the distance correction amount in a correction model for correcting distance detection data depending on temperature; and treating the state of the optical sensor where the failure indicator is outside the allowable range as a failure state, and adjusting the control parameter for controlling the optical sensor to recover from the failure state.

[0019] According to the seventh to ninth aspects, in a correction model for correcting distance detection data depending on temperature, a failure indicator correlated with the fluctuation range of a correction parameter that defines the temperature dependency of the distance correction amount is monitored. Therefore, when the failure indicator falls outside the allowable range, the optical sensor is considered to be in a fault state, and the control parameters for controlling the optical sensor are adjusted to recover from the fault state. In this way, the optical sensor can recover from the fault state by adjusting the control parameters. Under this recovery state, the detection data is corrected according to the temperature at each distance detection in accordance with the correction model, enabling the output of detection data with ensured distance detection accuracy.

[0020] A tenth aspect of the present disclosure is an optical sensor that receives a reflected beam from a target in response to a projected beam projected onto a detection area and outputs detection data that detects the distance to the target, and is configured to include a control device of the first, fourth, or seventh aspect, and is equipped with: a control unit that generates the detection data; a light projecting unit that projects the projected beam in accordance with control by the control unit; and a light receiving unit that receives the reflected beam in accordance with control by the control unit.

[0021] The optical sensor of the tenth aspect can achieve the same effects based on the same principle as the control device of the first, fourth or seventh aspect.

[0022] 1 is a cross-sectional view showing the overall configuration of an optical sensor according to a first embodiment; FIG. 2 is a block diagram showing the functional configuration of an optical sensor according to the first embodiment; FIG. 3 is a schematic diagram showing a light projecting light source unit according to the first embodiment; FIG. 4 is a schematic diagram showing a light receiving and detecting unit according to the first embodiment; FIG. 5 is a flowchart showing a control flow according to the first embodiment; FIG. 6 is a time chart for explaining the control flow according to the first embodiment; FIG. 7 is a characteristic diagram for explaining the control flow according to the first embodiment; FIG. 8 is a characteristic diagram for explaining the control flow according to the first embodiment; FIG. 9 is a cross-sectional view showing a modification of FIG. 2; FIG. 10 is a characteristic diagram for explaining the control flow according to the first embodiment; FIG. 11 is a characteristic diagram for explaining the control flow according to the second embodiment; FIG. 12 is a characteristic diagram for explaining the control flow according to the third embodiment; and FIG. 13 is a characteristic diagram for explaining the control flow according to the fourth embodiment.

[0023] Hereinafter, multiple embodiments of the present disclosure will be described with reference to the drawings. Note that corresponding components in each embodiment are designated by the same reference numerals, and redundant description may be omitted. Furthermore, when only a portion of the configuration is described in each embodiment, the configuration of another previously described embodiment may be applied to the remaining portions of the configuration. Furthermore, in addition to the combinations of configurations explicitly stated in the description of each embodiment, configurations of multiple embodiments may be partially combined together even if not explicitly stated, provided that there is no particular problem with the combination.

[0024] First Embodiment As shown in FIG. 1 , an optical sensor 10 according to a first embodiment of the present disclosure is a LiDAR (Light Detection and Ranging / Laser Imaging Detection and Ranging) sensor that can be mounted on a mobile object 1 and optically detects the external environment of the mobile object 1. The mobile object 1 to which the optical sensor 10 is applied is, for example, an automobile capable of at least one of manual driving, automatic driving, and remote driving. In the following description, unless otherwise specified, the directions indicated as front, rear, up, down, left, and right are defined with respect to the mobile object 1 on a horizontal plane. In the following description, the horizontal direction and the vertical direction refer to the directions parallel to and perpendicular to the horizontal plane, respectively, of the mobile object 1 on the horizontal plane. However, in FIG. 1 , the left side of the dashed-dotted line along the vertical direction (the side of a cover panel 12 described below) actually illustrates a cross section perpendicular to the right side of the dashed-dotted line (the side of components 21 and 41 described below).

[0025] The optical sensor 10 is disposed in at least one location on the mobile body 1, such as the front, left and right side portions, rear portion, or upper roof. As shown in Figures 1 and 2, the optical sensor 10 projects a projected beam PB toward a detection area DA in the outside world that corresponds to the location of the optical sensor 10 on the mobile body 1. The optical sensor 10 detects, as a reflected beam RB, light that returns when the projected beam PB is reflected by a target Xt in the detection area DA in the outside world. For the projected beam PB that becomes the reflected beam RB, light in the near-infrared range that is difficult for humans to see is selected.

[0026] The optical sensor 10 detects a target Xt present in a detection area DA in the external world by receiving a reflected beam RB reflected by the projected beam PB. The detection of such an external target Xt may involve the detection of one or more types of information, including at least the distance L, such as the distance L from the optical sensor 10 to the target Xt, the direction in which the target Xt is located, and the reflection intensity of the reflected beam RB from the target Xt. The target Xt that is typically detected by the optical sensor 10 applied to the moving body 1 may be at least one of moving objects such as pedestrians, cyclists, non-human animals, and other vehicles. The target Xt that is typically detected by the optical sensor 10 applied to the moving body 1 may be at least one of stationary objects such as guardrails, road signs, roadside structures, and fallen objects on the road.

[0027] 1 , the optical sensor 10 includes a housing 11, a light-projecting unit 21, a scanning unit 31, a light-receiving unit 41, and a control unit 51. The light-shielding housing 11 is formed into a box shape from, for example, metal or resin. The housing 11 houses the light-projecting unit 21, the scanning unit 31, the light-receiving unit 41, and the control unit 51. An opening that penetrates the housing 11 from the inside to the outside is closed by a cover panel 12. The light-transmitting cover panel 12 is formed from, for example, resin or glass, and separates the inside and outside of the housing 11.

[0028] As shown in FIGS. 1 and 2 , the light projecting unit 21 includes a light projecting light source unit 22 and a light projecting lens unit 26. As shown in FIG. 3 , the light projecting light source unit 22 is constructed by mounting a plurality of light source elements 24 in an array on a substrate. The light source elements 24 are laser diodes arranged in a single row (as shown in the example of FIG. 3 ) or in multiple rows (not shown) along the vertical direction. In response to a control signal from the control unit 51, the light source elements 24 generate pulsed laser light that becomes a portion of the light projecting beam PB. The light source elements 24 may be edge-emitter lasers or vertical cavity surface-emitting lasers (VCSELs).

[0029] The light projecting light source unit 22 has a light source window 25 formed on one side of the substrate, the light source window 25 being defined as a quasi-rectangular outline with its long sides extending vertically and its short sides extending horizontally. The light source window 25 is configured as a collection of laser oscillation apertures in each light source element 24. The laser light projected from the laser oscillation aperture of each light source element 24 is projected from the light source window 25 as a projecting beam PB that is quasi-rectangular and extends vertically in at least the external detection area DA.

[0030] As shown in FIG. 1 , the projection lens unit 26 is constructed in a structure in which at least one projection lens 27 is held in a lens barrel 28. The light-transmitting projection lens 27 is formed mainly from a base material such as resin or glass and has a lens shape corresponding to the optical function to be exerted. The projection lens 27 exerts at least one optical function, such as focusing, collimating, and shaping, on the projection beam PB from the projection light source unit 22. The projection lens 27 is positioned within a light-blocking lens barrel 28 made of, for example, metal or resin. The projection lens unit 26 configured in this manner is aligned with the projection light source unit 22 to form a projection optical axis PO that guides the projection beam PB toward the scanning unit 31.

[0031] 1 and 2, the scanning unit 31 has a scanning mirror 32 and a scanning motor 35. The scanning mirror 32 is constructed in the shape of a plate with a reflective film deposited on a reflective surface 33, which is one side of a base material. The scanning mirror 32 is supported by the housing 11 so as to be rotatable about a rotation center line along the vertical direction. The scanning mirror 32 oscillates within a driving range that is limited by a mechanical or electrical stopper.

[0032] The scanning motor 35 is, for example, a voice coil motor, a brushed DC motor, or a stepping motor. The output shaft of the scanning motor 35 is coupled directly to the scanning mirror 32 or indirectly via a drive mechanism such as a reducer. The scanning motor 35 is held by the housing 11 so as to be able to rotate the scanning mirror 32 together with its output shaft. The scanning motor 35 rotates (i.e., oscillates) the scanning mirror 32 within a limited driving range in accordance with a control signal from the control unit 51.

[0033] The scanning mirror 32 reflects the projected beam PB incident from the light projecting unit 21 by the reflecting surface 33 and projects it onto the detection area DA through the cover panel 12, thereby scanning the area DA in accordance with the rotation angle of the scanning motor 35. At this time, scanning of the detection area DA by the projected beam PB is substantially limited to scanning in the horizontal direction in this embodiment, in accordance with the rotational drive of the scanning mirror 32.

[0034] The scanning mirror 32 reflects the reflected beam RB, which is incident from the target Xt in the detection area DA through the cover panel 12, toward the light receiving unit 41 by the reflecting surface 33 in accordance with the rotation angle of the scanning motor 35. At this time, the speeds of the projected beam PB and the reflected beam RB are sufficiently greater than the rotational speed of the scanning mirror 32. As a result, the reflected beam RB is reflected by the scanning mirror 32, which can be assumed to have substantially the same rotation angle with respect to the projected beam PB, and is guided toward the light receiving unit 41 in the opposite direction to the projected beam PB.

[0035] The light receiving section 41 includes a light receiving lens unit 42 and a light receiving and detecting unit 45. As shown in FIG. 1 , 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 formed mainly from a base material such as resin or glass into a lens shape corresponding to the optical function to be exerted. The light receiving lens 43 exerts an optical function to form an image of the reflected beam RB from the scanning mirror 32 on the light receiving and detecting unit 45. The light receiving lens 43 is positioned within the light blocking lens barrel 44 formed from, for example, metal or resin. The light receiving lens unit 42 configured as described above is aligned with the light receiving and detecting unit 45, so that the light receiving optical axis RO, which guides the reflected beam RB from the scanning section 31 toward the unit 45, is offset in the vertical direction from the light projection optical axis PO of the light projecting lens unit 26.

[0036] As shown in FIG. 4 , the light-receiving detection unit 45 is constructed by mounting a plurality of light-receiving pixels 46 in an array on a substrate. The light-receiving pixels 46 are arranged at least vertically. The light-receiving detection unit 45 has a light-receiving surface 450 formed on one side of the substrate, the light-receiving surface 450 having a rectangular outline with its long sides extending vertically and its short sides extending horizontally. The light-receiving surface 450 is configured as a collection of the incident surfaces of the light-receiving pixels 46. Each light-receiving pixel 46 further includes a plurality of light-receiving elements 460, such as single photon avalanche diodes. Each light-receiving pixel 46 receives a reflected beam RB incident on the light-receiving surface 450 from the light-receiving lens unit 42, as shown in FIG. 1 .

[0037] 1 and 2, the light receiving and detecting unit 45 is provided with an output circuit 47. The output circuit 47 executes sampling processing for each scanning line according to the rotation angle of the scanning mirror 32, which is synchronized with the light projection cycle of the light projecting beam PB from the light projecting light source unit 22, for each detection cycle in accordance with a control signal from the control unit 51. At this time, the output circuit 47 generates a detection signal by combining response outputs from the light receiving elements 460 of each light receiving pixel 46 for each detection cycle. The detection signals generated in this manner are output from the output circuit 47 to the control unit 51 for each scanning line.

[0038] The control unit 51 is configured as a control device including at least one dedicated computer mounted on a board. The dedicated computer constituting the control device as the control unit 51 may be a sensor ECU (Electronic Control Unit) specialized for controlling the optical sensor 10, in which case the sensor ECU is housed in the housing unit 11 (example of FIG. 1 ). The dedicated computer constituting the control device as the control unit 51 may be a driving control ECU specialized for controlling the driving of the mobile object 1, in which case the driving control ECU is located outside the housing unit 11 in the mobile object 1 (not shown).

[0039] 1, the dedicated computer constituting the control device as the control unit 51 has at least one memory 51a and one processor 51b. The memory 51a is at least one type of non-transitory tangible storage medium, such as a semiconductor memory, a magnetic medium, or an optical medium, that non-temporarily stores computer-readable programs and data. The processor 51b includes at least one type of core, such as a central processing unit (CPU), a graphics processing unit (GPU), a reduced instruction set computer (RISC)-CPU, a data flow processor (DFP), or a graph streaming processor (GSP).

[0040] The control unit 51 configured as above is connected to the light projecting light source unit 22, the scanning motor 35, and the light receiving and detecting unit 45. The control unit 51 controls the light projecting light source unit 22 so as to generate the light projecting beam PB for each light projection cycle. At the same time, the control unit 51 controls the scanning motor 35 so as to control the scanning and reflection by the scanning mirror 32 in synchronization with the light projection cycle by the light projecting light source unit 22. Furthermore, the control unit 51 processes a detection signal output from the output circuit 47 of the light receiving and detecting unit 45, which is controlled in accordance with the light projection by the light projecting light source unit 22 and the scanning and reflection by the scanning mirror 32. In this way, the control unit 51 generates detection data that at least detects the distance L to the target Xt in the detection area DA.

[0041] To specifically realize such control, the processor 51b executes a plurality of instructions included in a control program stored in the memory 51a, causing the control unit 51 to construct a plurality of functional blocks for controlling the optical sensor 10. The plurality of functional blocks constructed by the control unit 51 in this manner include an update block 100 and a detection block 120, as shown in FIG.

[0042] The control method in which the control unit 51 controls the optical sensor 10 through cooperation of these blocks 100 and 120 is executed according to the control flow shown in Fig. 5. This control flow is repeatedly executed for each detection cycle while the moving body 1 is in motion. Note that each "S" in the control flow represents a plurality of steps executed by a plurality of commands included in the control program.

[0043] In S10 shown in FIG. 5 , the update block 100 (see FIG. 2 ) determines whether the current detection cycle satisfies the conditions of the monitoring period Pm. Here, the monitoring period Pm is a period for monitoring the fluctuation range δM of the correction parameter Mp in the correction model M, which will be described later. The monitoring period Pm is set to the stop period Ps shown in FIG. 6 , which is at least a period during which the moving object 1 is stopped. The monitoring period Pm may also be set to a stop period Ps with additional conditions, such as when the moving object 1 is stopped in a parking lot. The stop of the moving object 1, which triggers the setting of such a stop period Ps, may be recognized based on the detection result of the traveling speed by, for example, a speed sensor mounted on the moving object 1. The stop of the moving object 1 may also be recognized based on the detection result of the road surface by, for example, an optical sensor 10, other LiDAR, or a camera mounted on the moving object 1. The stop of the moving object 1 may also be recognized by fusing the detection results of the traveling speed and the road surface. 6, an example of the time transition of the operating state of the optical sensor 10 is diagrammatically shown, with the temperature T° C. (particularly the temperature Ta described below) serving as a state indicator of the optical sensor 10 being plotted on the vertical axis.

[0044] The monitoring period Pm may be set when the activation monitoring condition is satisfied during the activation period Pss shown in FIG. 6 during which the optical sensor 10 is activated, even during the stop period Ps of the moving object 1. Here, the activation monitoring condition may be specified so as to be satisfied every time a set time has elapsed since the activation period Pss was previously set to the monitoring period Pm. The activation monitoring condition may be specified so as to be satisfied every time the number of occurrences of the activation period Pss reaches a set number since the activation period Pss was previously set to the monitoring period Pm. Note that activation of the optical sensor 10 refers to at least one of simultaneous activation of the moving object 1 and the optical sensor 10 in response to an activation command from a user, automatic activation of the optical sensor 10 by waking up the moving object 1 from sleep mode, for example, at night, in response to a user command, and the like.

[0045] The monitoring period Pm may be set when a steady-state monitoring condition is met during a steady-state period Psr in FIG. 6 during a stop period Ps of the moving object 1, in which the operation of the optical sensor 10 stabilizes and the sensor 10 enters a steady state after the start period Pss. Here, the steady-state monitoring condition may be specified so as to be met every time a set time has elapsed since the steady-state period Psr was set to the monitoring period Pm in the past. The steady-state monitoring condition may be specified so as to be met every time the number of occurrences of the steady-state period Psr reaches a set number since the steady-state period Psr was set to the monitoring period Pm in the past.

[0046] As shown in FIG. 5, if a positive determination is made in S10, S20 is executed. In S20, the update block 100 monitors a correction model M (see FIGS. 7 and 8, described in detail below) that calculates a correction amount ΔL for correcting the detection data of the distance L depending on the temperature T. In this case, S20 monitors a fluctuation range δM of a correction parameter Mp that defines the degree of dependency of the correction amount ΔL of the distance L on the temperature T in the correction model M. Here, the correction amount ΔL is defined as a positive / negative detection deviation amount that depends on the temperature T, with the detected distance L as the reference. Furthermore, temperatures Ta, Tb, and Tc (see Equations 1 and 5, described below) of each of a specific number of sensor elements that make up the optical sensor 10 are taken into consideration as the temperature T.

[0047] Specifically, in S20, when the current detection cycle corresponds to the startup period Pss set in the monitoring period Pm of the shutdown period Ps, the startup parameter Mps is monitored as a correction parameter Mp that provides a correction model M for the startup period Pss, as shown in Fig. 7. At this time, the startup parameter Mps is assumed to depend on the detected deviation of the distance L for each of the temperatures Ta, Tb, and Tc for each of a specific number of sensor elements that make up the optical sensor 10, and coefficient parameters As, Bs, and Cs that represent the degree of dependency on these temperatures Ta, Tb, and Tc are assumed according to Equation 1. The startup parameter Mps also includes a constant parameter Ds that is common to the temperatures Ta, Tb, and Tc, assumed according to Equation 1.

[0048] In the above equation (1), the functions Ga, Gb, and Gc are defined as polynomials or monomials of degree 1 or greater with respect to the corresponding temperatures Ta, Tb, and Tc, respectively, and having no constant term. Therefore, in each polynomial term or monomial constituting the function Ga, a coefficient corresponding to the exponent of the temperature Ta is defined as a parameter As. Thus, particularly in the case of a polynomial, an individual parameter As is defined for each exponent of the temperature Ta in each term. The relationships between the parameters Bs and Cs and the corresponding functions Gb and Gc are defined in accordance with the relationship between the parameter As and the function Ga.

[0049] In this way, the parameters As, Bs, Cs, and Ds assumed for the startup parameter Mps are stored in the memory 51a as initial values ​​at the time of shipment of the optical sensor 10 or updated values ​​(described later) during the startup period Pss. Therefore, the stored values ​​of the parameters As, Bs, Cs, and Ds are defined as a stored parameter Mpm related to the startup parameter Mps, as shown in FIG.

[0050] Here, the sensor element corresponding to temperature Ta is the light projecting light source unit 22. The temperature Ta of the light projecting light source unit 22 is measured by a temperature sensor 29 (see FIG. 3) on the same board as each light source element 24. On the other hand, the sensor element corresponding to temperature Tb is the light receiving and detecting unit 45. Since the temperature Tb of the light receiving and detecting unit 45 correlates with the temperature Ta of the light projecting light source unit 22, it is estimated in accordance with the function Fb of Equation 2. Furthermore, the sensor element corresponding to temperature Tc is the control device serving as the control unit 51, or the mounting board thereof. Since the temperature Tc of the control device or the mounting board correlates with the temperature Ta of the light projecting light source unit 22, it is estimated in accordance with the function Fc of Equation 3.

[0051] If the current detection cycle corresponds to the startup period Pss set for the monitoring period Pm, in S20 the update block 100 changes the temperatures Ta, Tb, and Tc of each sensor element to the trial temperature Tt shown in Fig. 9. At this time, the change points of the temperatures Ta, Tb, and Tc as the trial temperature Tt are set at multiple points so that each point of the temperatures Ta, Tb, and Tc corresponds to another point based on the correlation of Equations 2 and 3. Therefore, the update block 100 may directly set multiple change points of the temperature Ta by controlling the light emission of each light source element 24 of the projector light source unit 22 to adjust the light emission power, and may also indirectly set multiple change points of the temperatures Tb and Tc according to Equations 2 and 3. 10, the update block 100 may indirectly set multiple change points of the temperature Ta correlated with the ambient temperature Ti in the housing 11 according to the function Fa of Equation 4, and multiple change points of the temperatures Tb and Tc according to Equations 2 and 3, by adjusting the ambient temperature Ti inside the housing 11 using a temperature adjustment unit 61 additionally connected to the control unit 51. Here, the temperature adjustment unit 61 is configured from at least one type of unit, for example, a heater unit, a cooling unit, etc.

[0052] If the current detection cycle corresponds to the startup period Pss set for the monitoring period Pm, in S20, the update block 100 acquires the distance L detected by the optical sensor 10 for each corresponding change point (hereinafter referred to as each corresponding change point) between the temperatures Ta, Tb, and Tc as the trial temperature Tt as the trial distance Lt, as shown in FIG. 9 . In this case, the trial distance Lt for each corresponding change point between the temperatures Ta, Tb, and Tc may be detected by the optical sensor 10 of the stationary moving body 1 receiving a reflected beam RB from a stationary (stopped) target Xt, such as a structure or a stopped vehicle. Here, the stationary state of the target Xt may be recognized based on the detection result of the target Xt by, for example, the optical sensor 10, other LiDAR, or a camera mounted on the moving body 1.

[0053] Therefore, the update block 100 in S20 during the startup period Pss acquires, as trial parameters Mpt by, for example, regression analysis, startup parameters Mps that provide a correction model M so as to interpolate the detected deviation of the trial distance Lt acquired at a specific reference correspondence change point between the temperatures Ta, Tb, and Tc, as shown in Fig. 7, for the trial distance Lt acquired at each correspondence change point between the temperatures Ta, Tb, and Tc. The startup parameters Mps acquired as the trial parameters Mpt at this time are assumed to include the parameters As, Bs, Cs, and Ds according to Equation 1. Note that Figs. 7 and 9 respectively show an example of the correction model M using the startup parameters Mps and distance detection during the startup period Pss, with the temperature Ta corresponding to the temperatures Tb and Tc being plotted on the horizontal axis of the temperatures T and Tt according to Equations 2 and 3. 7 and 9, the corresponding change points between the temperatures Ta, Tb, and Tc are indicated by black circles, and the temperature Ta at the reference corresponding change point that serves as the reference for the amount of detected deviation is indicated by the symbol T0s.

[0054] If the current detection cycle corresponds to the startup period Pss set for the monitoring period Pm, in S20 the update block 100 reads from the memory 51a the parameters As, Bs, and Cs, which are the most recent stored parameters Mpm for the startup parameter Mps. In S20 during the startup period Pss, the update block 100 focuses on the difference between the trial parameter Mpt acquired in the current detection cycle for the startup parameter Mps and the most recent stored parameter Mpm read for the startup parameter Mps as a fluctuation range δM, and monitors the coefficient parameters As, Bs, and Cs corresponding to each sensor element. In this case, in the function Ga of Equation 1, the fluctuation range δM is monitored for each coefficient parameter As of each term with a different exponent of the temperature Ta in a polynomial, or for the coefficient parameter As corresponding to the exponent of the temperature Ta alone in a monomial. Similarly, for the functions Gb and Gc of the above-mentioned equation (1), the fluctuation range δM is monitored for each of the coefficient parameters Bs and Cs of the terms having different exponents of the temperatures Tb and Tc in the polynomial, or for each of the coefficient parameters Bs and Cs alone corresponding to the exponents of the temperatures Tb and Tc in the monomial.

[0055] By such monitoring, in S20 during the startup period Pss, if the fluctuation range δM corresponding to at least one sensor element among the fluctuation ranges δM for the coefficient parameters As, Bs, and Cs increases outside the preset allowable range, the stored parameter Mpm related to the startup parameter Mps is updated in the memory 51a as shown in Fig. 5. In this update of the startup parameter Mps, learning of the stored parameter Mpm using the trial parameter Mpt is performed for each of the coefficient parameters As, Bs, and Cs for each sensor element. At the same time, in the update of the startup parameter Mps, learning of the stored parameter Mpm using the trial parameter Mpt is also performed simultaneously for the constant parameter Ds.

[0056] On the other hand, in S20, if the current detection cycle corresponds to the steady period Psr set in the monitoring period Pm of the stopped period Ps, the steady-state parameter Mpr is monitored as the correction parameter Mp that provides the correction model M for the steady-state period Psr, as shown in FIG. 8 . In this case, the steady-state parameter Mpr is assumed to depend on the temperatures Ta, Tb, and Tc of each of the multiple sensor elements, as in the case of the started period Pss, and coefficient parameters Ar, Br, and Cr that represent the degree of dependence on these temperatures Ta, Tb, and Tc are assumed according to Equation 5. The steady-state parameter Mpr also includes a constant parameter Dr that is common to the temperatures Ta, Tb, and Tc, as shown in Equation 5. Here, since the optical sensor 10 enters a steady state during the traveling period Pd of the moving object 1 after leaving the stopped period Ps and starting to travel, as shown in FIG. 6 , the steady-state parameter Mpr is also assumed and monitored as the correction parameter Mp that provides the correction model M for the steady-state period Pdr in the steady state.

[0057] In the above equation (5), the functions Ha, Hb, and Hc are defined as polynomials or monomials of degree 1 or greater with respect to the corresponding temperatures Ta, Tb, and Tc, respectively, and having no constant term. Therefore, in each term or monomial of the polynomial that constitutes the function Ha, a coefficient corresponding to the exponent of the temperature Ta is defined as the parameter Ar. Thus, particularly in the case of a polynomial, an individual parameter Ar is defined for each exponent of the temperature Ta in each term. The relationships between the parameters Br and Cr and the corresponding functions Hb and Hc are defined in accordance with the relationship between the parameter Ar and the function Ha.

[0058] In this way, the parameters Ar, Br, Cr, and Dr assumed for the steady-state parameter Mpr are stored in the memory 51a as initial values ​​at the time of shipment of the optical sensor 10 or updated values ​​(described later) during the steady-state period Psr. Therefore, the stored values ​​of the parameters Ar, Br, Cr, and Dr are defined as stored parameters Mpm related to the steady-state parameter Mpr, as shown in FIG.

[0059] If the current detection cycle corresponds to the steady period Psr set in the monitoring period Pm, in S20 the update block 100 changes the temperatures Ta, Tb, and Tc of each sensor element to the trial temperature Tt shown in Fig. 11. At this time, the method of changing the temperatures Ta, Tb, and Tc as the trial temperature Tt is the same as in the case of the startup period Pss.

[0060] If the current detection cycle corresponds to the steady period Psr set for the monitoring period Pm, in S20 the update block 100 acquires the distance L detected by the optical sensor 10 for each corresponding change point between the temperatures Ta, Tb, and Tc, which are the trial temperature Tt, as the trial distance Lt, as shown in FIG. 11. In this case, the trial distance Lt for each corresponding change point between the temperatures Ta, Tb, and Tc may be the distance L to the stationary target Xt, as in the case of the startup period Pss. Here, the stationary state of the target Xt may be recognized based on the detection result of the target Xt by, for example, the optical sensor 10, other LiDAR, or a camera mounted on the moving body 1.

[0061] Therefore, the update block 100 in S20 during the steady-state period Psr acquires, as trial parameters Mpt by, for example, regression analysis, steady-state parameters Mpr that provide a correction model M so as to interpolate the detected deviation of the trial distance Lt acquired at a specific reference correspondence change point between the temperatures Ta, Tb, and Tc, as shown in Fig. 8, for the trial distance Lt acquired at each correspondence change point between the temperatures Ta, Tb, and Tc. The steady-state parameters Mpr acquired as the trial parameters Mpt are assumed to be the parameters Ar, Br, Cr, and Dr according to Equation 5. In Figs. 8 and 11, the temperature Ta corresponding to the temperatures Tb and Tc is plotted on the horizontal axis of the temperatures T and Tt according to Equations 2 and 3, and examples of the correction model M using the steady-state parameters Mpr and distance detection during the steady-state period Psr are shown. 8 and 11, the corresponding change points are indicated by black circles in accordance with the start-up period Pss in FIGS. 7 and 9, and among them, the temperature Ta different from the start-up period Pss is indicated by the symbol T0r as the reference corresponding change point.

[0062] If the current detection cycle corresponds to the steady-state period Psr set for the monitoring period Pm, in S20 the update block 100 reads from the memory 51a the parameters Ar, Br, and Cr that are the most recently stored parameters Mpm for the steady-state parameter Mpr. In S20 during the steady-state period Psr, the update block 100 focuses on the difference between the trial parameter Mpt acquired in the current detection cycle for the steady-state parameter Mpr and the most recently stored parameter Mpm read for the steady-state parameter Mpr as a fluctuation range δM, and monitors the coefficient parameters Ar, Br, and Cr corresponding to each sensor element. In this case, in the function Ha of Equation 5 above, the fluctuation range δM is monitored for each coefficient parameter Ar of each term with a different exponent of the temperature Ta in a polynomial, or for the coefficient parameter Ar corresponding to the exponent of the temperature Ta alone in a monomial. Similarly, for the functions Hb and Hc of the above-mentioned equation (5), the fluctuation range δM is monitored for each of the coefficient parameters Br and Cr of the terms having different exponents of the temperatures Tb and Tc corresponding to the polynomials, or for each of the coefficient parameters Br and Cr corresponding to the exponents of the temperatures Tb and Tc corresponding to the monomials.

[0063] By such monitoring, in S20 of the steady-state period Psr, if the fluctuation range δM corresponding to at least one sensor element among the fluctuation ranges δM for the coefficient parameters Ar, Br, and Cr increases outside the preset allowable range, the stored parameter Mpm for the steady-state parameter Mpr is updated in the memory 51a as shown in Fig. 5. In this update of the steady-state parameter Mpr, learning of the stored parameter Mpm using the trial parameter Mpt is performed for each of the coefficient parameters Ar, Br, and Cr for each sensor element. At the same time, in the update of the steady-state parameter Mpr, learning of the stored parameter Mpm using the trial parameter Mpt is also performed simultaneously for the constant parameter Dr.

[0064] 5, if a positive determination is made in S10, the current execution of the control flow ends with the completion of execution of S20. On the other hand, if a negative determination is made in S10, S30 and S40 are executed in sequence. First, in S30, the detection block 120 (see FIG. 2) controls the light projecting light source unit 22, the scanning motor 35, and the light receiving detection unit 45 to generate detection data for the current detection cycle.

[0065] Next, in S40, the detection block 120 corrects the distance L of the detection data to be output by a correction amount ΔL that is adjusted to the current temperature Tp, which is the temperature T in the current detection cycle, in accordance with the correction model M given in accordance with the latest stored parameters Mpm. Specifically, the temperatures Ta, Tb, and Tc of each sensor element are acquired as the current temperature Tp at this time. Therefore, it is preferable that the temperature Ta is actually measured by the temperature sensor 29, and the temperatures Tb and Tc are further estimated according to Equations 2 and 3.

[0066] Therefore, in S40, if the current detection cycle corresponds to the startup period Pss within the shutdown period Ps that is not set as the monitoring period Pm, the detection block 120 reads from the memory 51a the stored parameters Mpm related to the startup parameters Mps of Equation 1. As a result, during the startup period Pss, the correction model M including the startup parameters Mps is selected as the input target for the current temperature Tp, and the corrected detection data according to the correction model M is output.

[0067] On the other hand, in S40, if the current detection cycle corresponds to a steady period Psr within the stopped period Ps that is not set as a monitoring period Pm, the detection block 120 reads out from the memory 51a the stored parameters Mpm related to the steady parameters Mpr of Equation 5. As a result, for the steady period Psr, a correction model M including the steady parameters Mpr is selected as the input target for the current temperature Tp, and corrected detection data according to the correction model M is output. In this embodiment, output of such corrected detection data according to the steady period Psr within the stopped period Ps is also performed in S40 when the current detection cycle corresponds to a steady period Pdr (see FIG. 6 ) that substantially coincides with the traveling period Pd of the mobile object 1 that has left the stopped period Ps.

[0068] In either case, the output of the detection data in S40 may be storing the detection data in the memory 51 a, providing the detection data to a driving control ECU, or transmitting the detection data to an external center via the communication unit of the vehicle 1.

[0069] The current execution of the control flow is completed upon completion of the execution of S40. Therefore, by repeating the control flow outside the monitoring period Pm, the detection data is corrected by the correction amount ΔL according to the temperature T for each detection cycle of the distance L.

[0070] (Operational Effects) The operational effects of the first embodiment described above will be described below.

[0071] According to the first embodiment, in the correction model M for correcting the detection data of the distance L depending on the temperature T, the fluctuation range δM of the correction parameter Mp, which defines the dependency of the correction amount ΔL of the distance L on the temperature T, is monitored. Therefore, if the fluctuation range δM of the correction parameter Mp falls outside the allowable range, the stored parameter Mpm stored in the memory 51a as the correction parameter Mp is updated. Therefore, by correcting the detection data by the correction amount ΔL that is matched to the current temperature Tp each time the distance L is detected in accordance with the correction model M given according to the latest stored parameter Mpm, it is possible to output detection data that ensures the detection accuracy of the distance L regardless of the passage of time.

[0072] According to the first embodiment, the trial temperature Tt is changed during the monitoring period Pm during which the fluctuation range δM of the correction parameter Mp is monitored. Therefore, the fluctuation range δM, which is the difference between the trial parameter Mpt, which serves as the correction parameter Mp that provides the correction model M according to the trial distance Lt detected by the optical sensor 10 at each change point of the trial temperature Tt during the monitoring period Pm, and the stored parameter Mpm, is monitored. This allows the trial parameter Mpt to be accurately determined based on the trial distance Lt at multiple temperature points when the monitored fluctuation range δM falls outside the allowable range, and the stored parameter Mpm to be updated. Therefore, by correcting the detection data according to the correction model M provided according to the updated stored parameter Mpm, it is possible to output detection data with improved detection accuracy for the distance L.

[0073] According to the first embodiment, during the monitoring period Pm set while the moving body 1 is stopped, the trial temperature Tt is changed, and the trial distance Lt to the stationary target Xt is detected by the optical sensor 10 at each change point of the trial temperature Tt. This makes it possible to effectively utilize the stationary target Xt, in which the distance L is substantially unchanged relative to the stopped moving body 1, and accurately monitor the fluctuation range δM occurring in the correction parameter Mp of the correction model M based on the trial distance Lt at multiple temperature points. Therefore, by correcting the detection data according to the correction model M that includes the correction parameter Mp as the latest stored parameter Mpm when the monitored fluctuation range δM falls outside the allowable range, it is possible to output detection data that ensures high detection accuracy of the distance L.

[0074] According to the first embodiment, the temperatures Ta, Tb, and Tc of each sensor element constituting the optical sensor 10 are each changed as a trial temperature Tt during the monitoring period Pm. Then, the optical sensor 10 detects the trial distance Lt at each change point of the trial temperature Tt during the monitoring period Pm. The trial parameters Mpt, which provide the correction model M according to the trial distance Lt, are monitored for each sensor element. Therefore, when the variation range δM corresponding to at least one sensor element falls outside the allowable range, the stored parameters Mpm are learned using the trial parameters Mpt for each sensor element. This allows the detection data to be accurately corrected according to the correction model M including the learned stored parameters Mpm. This enables the output of detection data that ensures high detection accuracy of the distance L.

[0075] According to the first embodiment, during the steady-state period Psr in which the optical sensor 10 reaches a steady state after the startup period Pss, the fluctuation range δM of the steady-state parameters Mpr is monitored as the correction parameters Mp that provide the correction model M. Therefore, if the fluctuation range δM monitored during the steady-state period Psr falls outside the allowable range, the stored parameters Mpm are updated with respect to the steady-state parameters Mpr. Therefore, by selecting the correction model M that is provided according to the latest stored parameters Mpm related to the steady-state parameters Mpr, correction appropriate for the steady-state periods Psr and Pdr in which the state of the optical sensor 10 reaches a steady state can be achieved for the detection data, thereby improving the detection accuracy of the distance L.

[0076] Moreover, according to the first embodiment, during the startup period Pss when the optical sensor 10 is started, the fluctuation range δM of the startup parameter Mps is monitored as the correction parameter Mp that provides the correction model M. Therefore, if the fluctuation range δM monitored during the startup period Pss falls outside the allowable range, the stored parameter Mpm is updated with respect to the startup parameter Mps. Therefore, during the startup period Pss, a correction model M corresponding to the latest stored parameter Mpm related to the startup parameter Mps is selected, thereby achieving correction of the detection data that is specific to the startup period Pss when the state of the optical sensor 10 changes from moment to moment, and making it possible to improve the detection accuracy of the distance L.

[0077] Second Embodiment The second embodiment is a modification of the first embodiment.

[0078] 12 , in the control flow of the second embodiment, S2020 is executed instead of S20. Specifically, in S2020, when the current detection cycle corresponds to the startup period Pss set for the monitoring period Pm, the update block 100 updates the stored parameter Mpm related to the startup parameter Mps as the correction parameter Mp when the fluctuation range δM corresponding to at least one sensor element among the coefficient parameters As, Bs, and Cs falls outside the preset allowable range. However, in updating the startup parameter Mps in S2020, the coefficient parameters As, Bs, and Cs corresponding to the sensor element whose fluctuation range δM falls outside the allowable range are forcibly set to zero (0) as failure parameters for any of the indices of the corresponding temperatures Ta, Tb, and Tc.

[0079] Therefore, in S2020, for the normal parameters among the coefficient parameters As, Bs, and Cs other than the fault parameter that has been updated to zero, the acquisition of the trial parameter Mpt is re-executed, for example, by regression analysis, and the stored parameter Mpm is learned based on the re-execution result. At this time, for the constant parameter Ds, the stored parameter Mpm is also learned based on the trial parameter Mpt that has been re-executed. Note that the fault parameter that has been forcibly set to zero in relation to the startup parameter Mps remains at zero, and acquisition of the trial parameter Mpt, monitoring of the fluctuation range δM, and updating of the stored parameter Mpm are skipped until maintenance of the optical sensor 10 is performed.

[0080] Similarly, in S2020, if the current detection cycle corresponds to the steady-state period Psr set for the monitoring period Pm, the update block 100 updates the stored parameters Mpm related to the steady-state parameters Mpr as the correction parameters Mp when the fluctuation range δM corresponding to at least one sensor element among the coefficient parameters Ar, Br, and Cr falls outside the preset allowable range, similar to S20. However, in updating the steady-state parameters Mpr in S2020, the coefficient parameters Ar, Br, and Cr corresponding to the sensor element whose fluctuation range δM falls outside the allowable range are forcibly set to zero (0) as fault parameters for any of the indices of the corresponding temperatures Ta, Tb, and Tc.

[0081] Therefore, in S2020, for the normal parameters among the coefficient parameters Ar, Br, and Cr other than the fault parameter that has been updated to zero, acquisition of the trial parameter Mpt is re-executed, for example, by regression analysis, and the stored parameter Mpm is learned based on the re-execution result. At this time, for the constant parameter Dr, the stored parameter Mpm is also learned based on the trial parameter Mpt that has been re-executed. Note that the fault parameter that has been forcibly set to zero in relation to the steady-state parameter Mpr remains at zero, and acquisition of the trial parameter Mpt, monitoring of the fluctuation range δM, and updating of the stored parameter Mpm are skipped until maintenance of the optical sensor 10 is performed.

[0082] According to the second embodiment described above, the fault parameter Mpm, which is the stored parameter of a sensor element whose fluctuation range δM falls outside the allowable range, is updated to zero. This allows the correction model M to be updated so that it is defined by the stored parameters Mpm of normal sensor elements, along with the zero-value fault parameter. Therefore, by correcting the detection data according to the updated correction model M, it becomes possible to output detection data in which a decrease in the detection accuracy of the distance L is suppressed.

[0083] Third Embodiment The third embodiment is a modification of the first embodiment.

[0084] 13 , in the control flow of the third embodiment, S3010 and S3020 are executed instead of S10 and S20. Specifically, in S3010, the update block 100 skips determining whether the startup monitoring condition is met during the startup period Pss, and sets the steady-state period Psr to the monitoring period Pm only when the steady-state monitoring condition is met. Accordingly, in S3020, the update block 100 skips obtaining the trial parameter Mpt, monitoring the fluctuation range δM, and updating the stored parameter Mpm for the startup parameter Mps as the correction parameter M.

[0085] Furthermore, in S3020, when the current detection cycle corresponds to the steady period Psr set for the monitoring period Pm, the update block 100 focuses on the fluctuation range δM for each of the coefficient parameters Ar, Br, and Cr corresponding to each sensor element for the steady-state parameter Mpr as the correction parameter M, similar to S20. However, in S3020, the update block 100 monitors the failure indicator Ir correlated with the fluctuation range δM for the steady-state parameter Mpr for each of the coefficient parameters Ar, Br, and Cr corresponding to each sensor element. That is, during the steady period Psr as the monitoring period Pm in the third embodiment, the failure indicator Ir correlated with the fluctuation range δM of the steady-state parameter Mpr as the correction parameter Mp is monitored for each sensor element.

[0086] At this time, in S3020, in the function Ha of Equation 5 described in the first embodiment, a failure probability correlated with the fluctuation range δM is estimated by the function I_n of Equation 6 for each coefficient parameter Ar of each term having a different exponent n (n: index for identifying the exponent) of the temperature Ta in the case of a polynomial, or for a single coefficient parameter Ar corresponding to the exponent n of the temperature Ta in the case of a monomial. Here, the failure probability function I_n is defined so as to represent a state in which the probability that the corresponding sensor element has failed due to, for example, aging deterioration increases as the fluctuation range δM of the coefficient parameter Ar increases.

[0087] Therefore, in S3020, when the function Ha of Equation 5 is a polynomial, the values ​​calculated by the failure probability function I_n for each coefficient parameter Ar with different exponents n of the temperature Ta are treated as multiple variables in the index function I_N of Equation 6 (e.g., a weighted average function), and the failure indicator Ir of the sensor element corresponding to the coefficient parameter Ar of each of these exponents n is monitored in accordance with the index function I_N. Alternatively, when the function Ha of Equation 5 is a monomial, the value calculated by the failure probability function I_n for a single coefficient parameter Ar according to the exponent n of the temperature Ta is treated as a single variable in the index function I_N of Equation 6 (e.g., a proportional function with a proportionality coefficient of 1), and the failure indicator Ir of the sensor element corresponding to that single coefficient parameter Ar is monitored in accordance with the index function I_N. In either case, the index function I_N that gives the failure indicator Ir is defined so that the calculated value increases in accordance with an increase in the failure probability due to the function I_n. Similarly, in the functions Hb and Hc of Equation 5 described in the first embodiment, the failure index Ir is monitored from the failure probability correlated with the fluctuation range δM for each of the coefficient parameters Br and Cr of the terms having different exponents n of the corresponding temperatures Tb and Tc in the polynomial, or for each of the coefficient parameters Br and Cr corresponding to the exponents n of the corresponding temperatures Tb and Tc in the monomial.

[0088] By such monitoring, in S3020, if the failure indicator Ir corresponding to at least one sensor element among the failure indicators Ir for each of the coefficient parameters Ar, Br, and Cr increases outside a preset allowable range, the update block 100 performs fail-safe processing. Specifically, the fail-safe processing in S3020 includes a notification processing and a control adjustment processing. In the notification processing in S3020, data representing failure notification information that notifies the mobile object 1 on which the optical sensor 10 is mounted of the state of the sensor element whose failure indicator Ir has fallen outside the allowable range as a failed state is diagnostically output from the control unit 51.

[0089] In the control adjustment process at S3020 together with the notification process, the control parameters for controlling the sensor element of the optical sensor 10 whose failure indicator Ir has fallen outside the allowable range are adjusted toward a recovery side for recovering from the failure state of the sensor element that is out of the allowable range. At this time, when the failure indicator Ir corresponding to a different index n or a single coefficient parameter Ar falls outside the allowable range, the control parameters of each light source element 24 of the light-projecting light source unit 22 of the light-projecting unit 21 that is determined to be in a failed state may be adjusted, for example, by increasing or decreasing the light emission power toward a recovery side from the failed state.

[0090] Furthermore, at this time, when the failure indicator Ir corresponding to a different index n or a single coefficient parameter Br falls outside the allowable range, the light-receiving detection unit 45 of the light-receiving unit 41 determined to be a sensor element in a faulty state may be adjusted, for example, by increasing or decreasing the light-receiving sensitivity of the light-receiving element 460 toward the recovery side from the fault state as a control parameter for each light-receiving pixel 46 by the output circuit 47. When the failure indicator Ir corresponding to a different index n or a single coefficient parameter Br falls outside the allowable range, the light-receiving detection unit 45 of the light-receiving unit 41 determined to be a sensor element in a faulty state may be adjusted, for example, by increasing the number of allocated pixels 46 (i.e., expanding the light-receiving area for each scan line) or by shifting the range of the allocation, under control of allocating some of the light-receiving pixels 46 as light-receiving areas for each scan line. Furthermore, if the failure index Ir corresponding to a different index n or a single coefficient parameter Cr falls outside the allowable range, and the control unit 51 determines that the sensor element is in a faulty state, the control adjustment process may be skipped and the notification process may be carried out alone.

[0091] (Operations and Effects) Operations and effects of the third embodiment described above will be described below.

[0092] According to the third embodiment, in a correction model M for correcting the detection data of the distance L depending on the temperature T, a failure indicator Ir correlated with the fluctuation range δM of a correction parameter Mp that defines the dependency of the correction amount ΔL of the distance L on the temperature T is monitored. Therefore, a state of the optical sensor 10 in which the failure indicator Ir falls outside the allowable range is determined to be a failure state, and failure notification information notifying the failure state is output. In this way, since the optical sensor 10 can accurately notify the failure state by the failure notification information, conversely, under a normal state in which no notification is made, the detection data is corrected according to the correction model M to match the current temperature Tp for each detection of the distance L, thereby enabling the output of detection data in which the detection accuracy of the distance L is ensured.

[0093] Moreover, according to the third embodiment, the state of the optical sensor 10 where the failure indicator Ir falls outside the allowable range is determined to be a failure state, and the control parameters for controlling the optical sensor 10 are adjusted to recover from the failure state. In this way, the optical sensor 10 can recover from the failure state by adjusting the control parameters, and under this recovery state, the detection data is corrected in accordance with the correction model M to match the current temperature Tp at each detection of the distance L, thereby making it possible to output detection data with the detection accuracy of the distance L ensured.

[0094] According to the third embodiment, the trial temperature Tt is changed during the monitoring period Pm, during which the failure indicator Ir, which correlates with the fluctuation range δM of the correction parameter Mp, is monitored. Therefore, the difference between the trial parameter Mpt, which serves as the correction parameter Mp that provides the correction model M according to the trial distance Lt detected by the optical sensor 10 at each change point of the trial temperature Tt during the monitoring period Pm, and the stored parameter Mpm is focused on as the fluctuation range δM. In this way, when the failure indicator Ir, which is monitored in correlation with the fluctuation range δM, falls outside the allowable range, it is possible to appropriately determine whether or not to output failure notification information based on the fluctuation of the trial parameter Mpt based on the trial distance Lt at multiple temperature points. Therefore, since the failure state can be accurately notified by the failure notification information, conversely, under normal conditions, the detection data is corrected according to the correction model M, enabling the output of detection data with the distance L detection accuracy ensured.

[0095] According to the third embodiment, during the monitoring period Pm set while the moving body 1 is stopped, the trial temperature Tt is changed, and the trial distance Lt to the stationary target Xt is detected by the optical sensor 10 at each change point of the trial temperature Tt. This makes effective use of the stationary target Xt, in which the distance L is substantially constant relative to the stopped moving body 1, to accurately grasp the fluctuation range δM occurring in the correction parameter Mp of the correction model M based on the trial distance Lt at multiple temperature points and reflect it in the failure indicator Ir. Therefore, when the monitored failure indicator Ir is within the allowable range, the detection data is corrected according to the correction model M including the normal correction parameter Mp, making it possible to output detection data with the detection accuracy of the distance L ensured.

[0096] According to the third embodiment, the temperatures Ta, Tb, and Tc of each sensor element constituting the optical sensor 10 are changed as a trial temperature Tt during a monitoring period Pm. During the monitoring period Pm, a failure indicator Ir correlated with a fluctuation width δM, which is the difference between the trial parameter Mpt that provides the correction model M according to the trial distance Lt detected by the optical sensor 10 at each change point of the trial temperature Tt and the stored parameter Mpm, is monitored for each sensor element. Therefore, when the failure indicator Ir corresponding to at least one sensor element falls outside the allowable range, the fluctuation of the trial parameter Mpt based on the trial distance Lt at multiple temperature points can be focused on for each sensor element to accurately determine whether or not to output failure notification information. Therefore, since a sensor element in a faulty state can be accurately notified by the failure notification information, conversely, under normal conditions, the detection data is corrected according to the correction model M, enabling the output of detection data with the distance L detection accuracy ensured.

[0097] Fourth Embodiment The fourth embodiment is a modified example in which the third embodiment is combined with the second embodiment.

[0098] As shown in FIG. 14 , the control flow of the fourth embodiment executes S4020 instead of S3020. Specifically, in S4020, the update block 100 performs a fail-safe notification process when the current detection cycle corresponds to the steady-state period Psr set in the monitoring period Pm and the failure indicator Ir corresponding to at least one sensor element among the coefficient parameters Ar, Br, and Cr falls outside a preset allowable range. This process is similar to S3020, except that the fail-safe process in S4020 also executes the update process for the steady-state parameters Mpr, which is a partial modification of the second embodiment, along with the notification process. That is, in the update process of S4020, the coefficient parameters Ar, Br, and Cr corresponding to the sensor element whose failure indicator Ir correlated with the fluctuation range δM falls outside the allowable range are forcibly set to zero (0) as failure parameters for any of the indices of the corresponding temperatures Ta, Tb, and Tc.

[0099] Therefore, in the update process of S4020, for the normal parameters among the coefficient parameters Ar, Br, and Cr other than the fault parameter that has been updated to zero, the trial parameter Mpt is re-acquired, for example, by regression analysis, and the stored parameter Mpm is learned based on the re-acquisition result. At this time, for the constant parameter Dr, the stored parameter Mpm is also learned based on the trial parameter Mpt that has been re-acquired. Note that the fault parameter that has been forcibly set to zero in relation to the steady-state parameter Mpr remains at zero, and acquisition of the trial parameter Mpt, monitoring of the fault indicator Ir, and update of the stored parameter Mpm are skipped until maintenance of the optical sensor 10 is performed.

[0100] According to the fourth embodiment described above, the fault parameter, which is the stored parameter Mpm, of a sensor element whose fault indicator Ir falls outside the allowable range is updated to zero. As a result, the correction model M can be updated so as to be defined by the zero-value fault parameter as well as the stored parameter Mpm of a normal sensor element. Therefore, even after a sensor element in a faulty state is notified by fault notification information, the detection data can be corrected according to the updated correction model M, thereby making it possible to output detection data in which a decrease in the detection accuracy of the distance L is suppressed.

[0101] (Other Embodiments) Although multiple embodiments have been described above, the present disclosure should not be construed as being limited to those embodiments, and can be applied to various embodiments within the scope of the gist of the present disclosure.

[0102] In the modifications of the first to fourth embodiments, the dedicated computer constituting the control device as the control unit 51 may have at least one of a digital circuit and an analog circuit as a processor. Here, the digital circuit is at least one of an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), a system on a chip (SOC), a programmable gate array (PGA), and a complex programmable logic device (CPLD). Furthermore, such a digital circuit may have a memory that stores a program.

[0103] In S10 of the control flow of the modified examples of the first and second embodiments, the determination of whether the startup period Pss is set to the monitoring period Pm may be omitted, thereby omitting the update of the startup parameter Mps by monitoring in S20 and S2020. In S40 of the control flow to which the modified example of the first and second embodiments that omits the startup period determination and update is applied, the reading and correction of the stored parameter Mpm related to the startup parameter Mps may be omitted. In S40 of the control flow to which the modified example of the first and second embodiments that omits the startup period determination and update is applied, instead of reading and correcting the stored parameter Mpm related to the startup parameter Mps, the stored parameter Mpm related to the steady-state parameter Mpr may be read and corrected.

[0104] In S10 in the control flow of the modified examples of the first and second embodiments, the determination of whether the steady period Psr is set in the monitoring period Pm may be omitted, thereby omitting the update of the steady parameter Mpr by monitoring in S20 and S2020. In S40 of the control flow to which the modified examples of the first and second embodiments that omit the steady period determination and update are applied, the correction itself of the stored parameter Mpm related to the steady parameter Mpr may be omitted.

[0105] In S20 and S2020 of the control flows of the modified examples of the first and second embodiments, one or two of the coefficient parameters As, Bs, and Cs may be unexpected as the startup parameters Mps during the startup period Pss set in the monitoring period Pm. In S20 and S2020 of the control flows to which a modified example of the unexpected startup parameters Mps is applied, the stored parameters Mpm for at least one of the coefficient parameters As, Bs, and Cs expected as the startup parameter Mps may be updated in accordance with a fluctuation width δM, which is the difference from the trial parameter Mpt. Furthermore, in S40 of the control flow to which a modified example of the unexpected startup parameters Mps is applied, at least one of temperatures Ta, Tb, and Tc may be obtained as the current temperature Tp corresponding to at least one of the coefficient parameters As, Bs, and Cs expected as the startup parameter Mps, and the stored parameters Mpm for the startup parameter Mps may be read out and corrected.

[0106] In S20, S2020, S3020, and S4020 of the control flows of the modified examples of the first to fourth embodiments, one or two of the coefficient parameters Ar, Br, and Cr may be unexpected as the steady-state parameters Mpr during the steady-state period Psr set in the monitoring period Pm. In S20, S2020, S3020, and S4020 of the control flows to which a modified example of such unexpected steady-state parameters Mpr is applied with respect to the first to fourth embodiments, the stored parameter Mpm for at least one of the coefficient parameters Ar, Br, and Cr expected as the steady-state parameter Mpr may be updated according to a fluctuation width δM that is the difference from the trial parameter Mpt. Furthermore, in S40 of the control flow in which a certain modified example of the unexpected steady-state parameter Mpr is applied, at least one of temperatures Ta, Tb, and Tc may be obtained as the current temperature Tp corresponding to at least one of the coefficient parameters Ar, Br, and Cr that is assumed to be the steady-state parameter Mpr, and correction may be performed by reading out the stored parameter Mpm related to the steady-state parameter Mpr.

[0107] In S20 and S2020 in the control flows of the modified examples related to the first and second embodiments, during the startup period Pss set in the monitoring period Pm, the distance L to a specific reflector in the housing 11 may be detected as the trial distance Lt, instead of the distance L to the stationary target Xt. In S20, S2020, S3020, and S4020 in the control flows of the modified examples related to the first to fourth embodiments, during the steady period Psr set in the monitoring period Pm, the distance L to a specific reflector in the housing 11 may be detected as the trial distance Lt, instead of the distance L to the stationary target Xt.

[0108] In the variations of the first to fourth embodiments, the control device that executes the above-described control method and control program as the control unit 51, and the mobile body 1 to which the optical sensor 10 equipped with the same is applied may be, for example, an autonomous robot that is capable of transporting luggage or collecting information by autonomous or remote driving. In the variations of the first to fourth embodiments, the control device that executes the above-described control method and control program as the control unit 51, and the optical sensor 10 equipped with the same may be applied to infrastructure equipment other than the mobile body 1, for example, a smart pole.

[0109] With regard to the first and second embodiments, in S20 and S2020 of the control flow for controlling the optical sensor 10 applied to infrastructure facilities as described above, the distance L to a specific point on the ground may be detected as the trial distance Lt, instead of the distance L to the stationary target Xt, during the startup period Pss set in the monitoring period Pm. With regard to the first to fourth embodiments, in S20, S2020, S3020, and S4020 of the control flow for controlling the optical sensor 10 applied to infrastructure facilities, the distance L to a specific point on the ground may be detected as the trial distance Lt, instead of the distance L to the stationary target Xt, during the steady period Psr set in the monitoring period Pm.

[0110] In a modification of the third and fourth embodiments, the fluctuation range δM itself may be monitored as a failure indicator Ir correlated with the fluctuation range δM focused on in S3020 and S4020. In a modification of the fourth embodiment, in the update process when the failure indicator Ir falls outside the allowable range in S4020, the stored parameter Mpm may be updated in a manner similar to that of the first embodiment. In a modification of the third and fourth embodiments, the notification process in S3020 and S4020 may be skipped. In a modification of the third embodiment, the control adjustment process in S3020 may be skipped. In a modification of the third and fourth embodiments, control similar to that described above may be performed during the startup period Pss in addition to or instead of the steady period Psr. In addition to the embodiments described above, the first to fourth embodiments and each of the modifications described above may be implemented in the form of a semiconductor device (e.g., a semiconductor chip) as the control unit 51.

[0111] (Additional Remarks) This specification discloses the following technical ideas and their combinations. Note that the reference characters in parentheses in the Additional Remarks section indicate the correspondence with the specific means described in the above-described embodiments, and do not limit the technical scope of the present disclosure.

[0112] (Technical Idea 1) A control device having a processor (51 b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected onto a detection area (DA) and outputs detection data that detects a distance (L) to the target, wherein the processor is configured to: monitor a fluctuation range (δM) of a correction parameter (Mp) that defines the temperature dependency of a correction amount (ΔL) of the distance in a correction model (M) for correcting the detection data of the distance depending on the temperature (T), and update a stored parameter (Mpm) stored in a storage medium (51 a) as the correction parameter when the fluctuation range falls outside an allowable range; and correct the detection data by the correction amount adjusted to the temperature each time the distance is detected, in accordance with the correction model given according to the latest stored parameter.

[0113] (Technical Idea 2) The control device according to Technical Idea 1, wherein updating the stored parameters by monitoring the fluctuation range includes: updating the stored parameters related to the startup parameters when the fluctuation range of the startup parameter (Mps), which is monitored as the correction parameter that provides the correction model for a startup period (Pss) in which the optical sensor is started, falls outside an allowable range; and updating the stored parameters related to the steady-state parameters when the fluctuation range of the steady-state parameter (Mpr), which is monitored as the correction parameter that provides the correction model for a steady-state period (Psr, Pdr) in which the optical sensor is in a steady state after the startup period, falls outside an allowable range; and correcting the detection data includes: selecting the correction model that is given in accordance with the latest stored parameters related to the startup parameters, and correcting the detection data for the startup period; and selecting the correction model that is given in accordance with the latest stored parameters related to the steady-state parameters, and correcting the detection data for the steady-state period.

[0114] (Technical Idea 3) A control device according to Technical Idea 1 or 2, wherein updating the stored parameter by monitoring the fluctuation range includes: changing a trial temperature (Tt), which is the temperature during a monitoring period (Pm) during which the fluctuation range is monitored; monitoring the fluctuation range, which is the difference between the stored parameter and a trial parameter (Mpt), which is the correction parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period; and updating the stored parameter with the trial parameter when the fluctuation range falls outside the allowable range.

[0115] (Technical Idea 4) A control device according to Technical Idea 3, which is an optical sensor that can be mounted on a moving body (1), and in which updating the stored parameters by monitoring the fluctuation range includes changing the trial temperature during the monitoring period that is set while the moving body is stopped, and detecting the distance to the stationary target by the optical sensor for each change point of the trial temperature during the monitoring period while the moving body is stopped.

[0116] (Technical Idea 5) The control device according to Technical Idea 3 or 4, wherein updating the stored parameters by monitoring the fluctuation range includes: changing the temperature of each sensor element constituting the optical sensor as the trial temperature during the monitoring period; monitoring the fluctuation range, which is the difference between the trial parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period, and the stored parameter, for each sensor element; and when the fluctuation range corresponding to at least one of the sensor elements falls outside the allowable range, learning the stored parameters using the trial parameters for each sensor element.

[0117] (Technical Idea 6) The control device according to Technical Idea 5, wherein updating the stored parameters by monitoring the fluctuation range includes updating the stored parameters of the sensor elements whose fluctuation range falls outside an allowable range to zero values.

[0118] (Technical Idea 7) A control device having a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected onto a detection area (DA) and outputs detection data that detects a distance (L) to the target, wherein the processor is configured to: monitor a failure index (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that defines the temperature dependency of the distance correction amount (ΔL) in a correction model (M) for correcting the detection data of the distance depending on temperature (T); and output failure notification information that notifies the optical sensor of the failure index being out of an allowable range when the state of the optical sensor is in a failure state.

[0119] (Technical Idea 8) A control device according to Technical Idea 7, wherein monitoring the failure indicator includes: changing a trial temperature (Tt), which is the temperature during a monitoring period (Pm) during which the failure indicator is monitored; and monitoring the failure indicator that correlates with the fluctuation range, which is the difference between a trial parameter (Mpt) as the correction parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period, and a stored parameter (Mpm) stored in a storage medium (51a) as the correction parameter.

[0120] (Technical Idea 9) The control device according to Technical Idea 8, wherein monitoring the failure indicator includes: changing the temperature of each sensor element constituting the optical sensor as the trial temperature during the monitoring period; and monitoring the failure indicator for each sensor element, the failure indicator correlating with the fluctuation range being the difference between the trial parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period and the stored parameter; and outputting the failure notification information includes outputting the failure notification information that notifies, as the failure state, the state of the sensor element where the failure indicator has fallen outside the allowable range.

[0121] (Technical Idea 10) The control device according to Technical Idea 9, wherein the processor is further configured to update the stored parameter of the sensor element whose failure indicator falls outside an acceptable range to a zero value.

[0122] (Technical Idea 11) The control device according to any one of Technical Ideas 7 to 9, wherein the processor is further configured to adjust a control parameter for controlling the optical sensor to recover from the failure state of the optical sensor whose failure indicator falls outside the allowable range.

[0123] (Technical Idea 12) A control device having a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected onto a detection area (DA) and outputs detection data that detects a distance (L) to the target, wherein the processor is configured to: monitor a failure index (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that defines the temperature dependency of a correction amount (ΔL) of the distance in a correction model (M) that corrects the detection data of the distance depending on temperature (T); and determine a state of the optical sensor when the failure index falls outside an allowable range as a failure state, and adjust a control parameter for controlling the optical sensor to recover from the failure state.

[0124] (Technical Idea 13) The control device according to Technical Idea 12, wherein monitoring the failure indicator includes: changing a trial temperature (Tt), which is the temperature during a monitoring period (Pm) during which the failure indicator is monitored; and monitoring the failure indicator that correlates with the fluctuation range, which is the difference between a trial parameter (Mpt) as the correction parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period, and a stored parameter (Mpm) stored in a storage medium (51a) as the correction parameter.

[0125] (Technical Idea 14) The control device according to Technical Idea 13, wherein monitoring the failure indicator includes: changing the temperature of each sensor element constituting the optical sensor as the trial temperature during the monitoring period; and monitoring the failure indicator for each sensor element, the failure indicator correlating with the fluctuation range being the difference between the trial parameter and the stored parameter, the trial parameter providing the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period; and adjusting the control parameter includes adjusting the control parameter for controlling the sensor element whose failure indicator has fallen outside the allowable range to recover from the failure state.

[0126] (Technical Idea 15) The control device according to Technical Idea 14, wherein adjusting the control parameters includes adjusting the control parameters for controlling a light-projecting unit (21) that projects the light beam as the sensor element whose failure indicator has fallen outside the allowable range, to a side that recovers from the failure state.

[0127] (Technical Idea 16) The control device according to Technical Idea 14 or 15, wherein adjusting the control parameters includes adjusting the control parameters for controlling a light receiving unit (41) that receives the reflected beam as the sensor element whose failure indicator has fallen outside the allowable range, to the recovery side of the failure state.

[0128] (Technical Idea 17) The optical sensor is configured to be mountable on a moving body (1), and monitoring the failure indicator includes: changing the trial temperature during the monitoring period set while the moving body is stopped; and detecting the distance to the stationary target by the optical sensor for each change point of the trial temperature during the monitoring period while the moving body is stopped.

[0129] (Technical Idea 18) An optical sensor that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected onto a detection area (DA) and outputs detection data that detects a distance (L) to the target, the optical sensor including a control device described in any one of Technical Ideas 1 to 17, and comprising: a control unit (51) that generates the detection data; a light projecting unit (21) that projects the projected beam in accordance with control by the control unit; and a light receiving unit (41) that receives the reflected beam in accordance with control by the control unit.

[0130] The above-mentioned technical concepts 1 to 17 may be understood as the respective technical concepts of the method and the program.

Claims

1. A control device having a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data that detects a distance (L) to the target, wherein the processor is configured to: monitor a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of the temperature on the correction amount (ΔL) of the distance in a correction model (M) for correcting the detection data of the distance depending on temperature (T), and update a stored parameter (Mpm) stored in a storage medium (51a) as the correction parameter when the fluctuation range falls outside an allowable range; and correct the detection data with the correction amount matched to the temperature each time the distance is detected, in accordance with the correction model given according to the latest stored parameter.

2. The control device of claim 1, wherein updating the stored parameters by monitoring the fluctuation range includes: updating the stored parameters related to the startup parameters when the fluctuation range of the startup parameter (Mps), which is monitored as the correction parameter that provides the correction model for the startup period (Pss) during which the optical sensor is started, falls outside an allowable range; and updating the stored parameters related to the steady-state parameters when the fluctuation range of the steady-state parameter (Mpr), which is monitored as the correction parameter that provides the correction model for the steady-state period (Psr, Pdr) during which the optical sensor is in a steady state after the startup period, falls outside an allowable range; and correcting the detection data includes: selecting the correction model given in accordance with the latest stored parameters related to the startup parameters to correct the detection data for the startup period; and selecting the correction model given in accordance with the latest stored parameters related to the steady-state parameters to correct the detection data for the steady-state period.

3. The control device of claim 1 or 2, wherein updating the stored parameter by monitoring the fluctuation range includes: changing a trial temperature (Tt), which is the temperature during a monitoring period (Pm) during which the fluctuation range is monitored; monitoring the fluctuation range, which is the difference between the stored parameter and a trial parameter (Mpt), which is the correction parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period; and updating the stored parameter with the trial parameter when the fluctuation range falls outside an acceptable range.

4. The optical sensor is configured to be mounted on a moving body (1), and updating the stored parameters by monitoring the fluctuation range includes: changing the trial temperature during the monitoring period set while the moving body is stopped; and having the optical sensor detect the distance to the stationary target for each point of change in the trial temperature during the monitoring period while the moving body is stopped.

5. The control device described in claim 3, wherein updating the stored parameters by monitoring the fluctuation range includes: changing the temperature of each sensor element constituting the optical sensor as the trial temperature during the monitoring period; monitoring the fluctuation range, which is the difference between the trial parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period, and the stored parameter, for each sensor element; and when the fluctuation range corresponding to at least one of the sensor elements falls outside the allowable range, learning the stored parameter using the trial parameter for each sensor element.

6. The control device according to claim 5, wherein updating the stored parameters by monitoring the fluctuation range includes updating the stored parameters of the sensor elements whose fluctuation range falls outside an acceptable range to a zero value.

7. A control device having a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data that detects a distance (L) to the target, wherein the processor is configured to: monitor a failure indicator (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of the correction amount (ΔL) of the distance on temperature in a correction model (M) for correcting the detection data of the distance depending on temperature (T); and output failure notification information that notifies the user of the failure state when the state of the optical sensor where the failure indicator falls outside an acceptable range is a failure state.

8. The control device of claim 7, wherein monitoring the failure indicator includes: varying a trial temperature (Tt), which is the temperature during a monitoring period (Pm) during which the failure indicator is monitored; and monitoring the failure indicator which correlates with the fluctuation range, which is the difference between a trial parameter (Mpt) as the correction parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period, and a stored parameter (Mpm) stored in a storage medium (51a) as the correction parameter.

9. The control device described in claim 8, wherein monitoring the failure indicator includes: changing the temperature of each sensor element constituting the optical sensor as the trial temperature during the monitoring period; and monitoring the failure indicator for each sensor element, which correlates with the fluctuation range, which is the difference between the stored parameter and the trial parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period; and outputting the failure notification information includes outputting the failure notification information that notifies, as the failure state, the state of the sensor element in which the failure indicator has fallen outside the acceptable range.

10. The control device of claim 9, wherein the processor is further configured to: update the stored parameters of the sensor elements for which the fault indicator falls outside an acceptable range to a zero value.

11. The control device of claim 7, wherein the processor is further configured to: adjust a control parameter for controlling the optical sensor to a recovery side of the fault condition of the optical sensor for which the fault indicator falls outside an acceptable range.

12. A control device having a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data that detects a distance (L) to the target, wherein the processor is configured to: monitor a failure indicator (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of the correction amount (ΔL) of the distance on temperature in a correction model (M) for correcting the detection data of the distance depending on temperature (T); and set a state of the optical sensor in which the failure indicator falls outside an acceptable range as a failure state, and adjust a control parameter for controlling the optical sensor to the recovery side of the failure state.

13. The control device of claim 12, wherein monitoring the failure indicator includes: varying a trial temperature (Tt), which is the temperature during a monitoring period (Pm) during which the failure indicator is monitored; and monitoring the failure indicator which correlates with the fluctuation range, which is the difference between a trial parameter (Mpt) as the correction parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period, and a stored parameter (Mpm) stored in a storage medium (51a) as the correction parameter.

14. The control device described in claim 13, wherein monitoring the failure indicator includes: changing the temperature of each sensor element constituting the optical sensor as the trial temperature during the monitoring period; and monitoring the failure indicator for each sensor element, the failure indicator correlating with the fluctuation range being the difference between the stored parameter and the trial parameter that provides the correction model according to the distance detected by the optical sensor for each change point of the trial temperature during the monitoring period; and adjusting the control parameter includes adjusting the control parameter for controlling the sensor element whose failure indicator has fallen outside the acceptable range to recover from the failure state.

15. The control device according to claim 14, wherein adjusting the control parameters includes adjusting the control parameters for controlling a light-projecting unit (21) that projects the light beam as the sensor element whose failure indicator has fallen outside the acceptable range, to the recovery side of the failure state.

16. The control device described in claim 14, wherein adjusting the control parameters includes adjusting the control parameters for controlling a light receiving unit (41) that receives the reflected beam as the sensor element whose failure indicator has fallen outside the acceptable range, to the recovery side of the failure state.

17. A control device as described in claim 8 or 13, wherein the optical sensor is configured to be mountable on a moving body (1), and monitoring the failure indicator includes: changing the trial temperature during the monitoring period set while the moving body is stopped; and detecting the distance to the stationary target by the optical sensor for each point of change in the trial temperature during the monitoring period while the moving body is stopped.

18. An optical sensor that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data that detects a distance (L) to the target, the optical sensor being configured to include a control device as described in any one of claims 1, 2, 7, and 12, and comprising: a control unit (51) that generates the detection data; a light-projecting unit (21) that projects the projected beam in accordance with the control of the control unit; and a light-receiving unit (41) that receives the reflected beam in accordance with the control of the control unit.

19. A control method executed by a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data that detects a distance (L) to the target, the control method comprising: monitoring a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of a correction amount (ΔL) of the distance in a correction model (M) for correcting the detection data of the distance depending on temperature (T), thereby updating a stored parameter (Mpm) stored in a storage medium (51a) as the correction parameter when the fluctuation range falls outside an allowable range; and correcting the detection data by the correction amount adjusted to the temperature each time the distance is detected, in accordance with the correction model given according to the latest stored parameter.

20. A control method executed by a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data detecting a distance (L) to the target, the control method comprising: monitoring a failure indicator (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of the correction amount (ΔL) of the distance on temperature in a correction model (M) for correcting the detection data of the distance depending on temperature (T); and outputting failure notification information that notifies the user of the failure state when the state of the optical sensor in which the failure indicator falls outside an allowable range is determined to be a failure state.

21. A control method executed by a processor (51b) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data that detects a distance (L) to the target, the control method comprising: monitoring a failure indicator (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of the correction amount (ΔL) of the distance on temperature in a correction model (M) for correcting the detection data of the distance depending on temperature (T); and determining a state of the optical sensor in which the failure indicator falls outside an allowable range as a failure state, and adjusting a control parameter for controlling the optical sensor to recover from the failure state.

22. A control program stored in a storage medium (51a) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data that detects a distance (L) to the target, the control program including instructions for causing a processor (51b) to execute said control, the control program including instructions for executing the following: in a correction model (M) for correcting the detection data of the distance depending on temperature (T), by monitoring a fluctuation range (δM) of a correction parameter (Mp) that specifies the dependency of the temperature on the correction amount (ΔL) of the distance, updating a stored parameter (Mpm) stored in the storage medium (51a) as the correction parameter when the fluctuation range falls outside an allowable range; and correcting the detection data by the correction amount adjusted to the temperature each time the distance is detected, in accordance with the correction model given according to the latest stored parameter.

23. A control program stored in a storage medium (51a) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data detecting a distance (L) to the target, the control program including instructions for causing a processor (51b) to execute said control, the control program including the instructions for executing the following: monitoring a failure indicator (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of the correction amount (ΔL) of the distance on temperature in a correction model (M) for correcting the detection data of the distance depending on temperature (T); and outputting failure notification information notifying the user of the failure state when the failure indicator falls outside an allowable range of the optical sensor.

24. A control program stored in a storage medium (51a) for controlling an optical sensor (10) that receives a reflected beam (RB) from a target (Xt) in response to a projected beam (PB) projected into a detection area (DA) and outputs detection data detecting a distance (L) to the target, the control program including instructions for causing a processor (51b) to execute said control, the control program including instructions for executing the following: monitoring a failure indicator (Ir) that correlates with a fluctuation range (δM) of a correction parameter (Mp) that specifies the degree of dependency of the correction amount (ΔL) of the distance on temperature in a correction model (M) for correcting the detection data of the distance depending on temperature (T); and determining a state of the optical sensor in which the failure indicator falls outside an allowable range as a failure state, and adjusting a control parameter for controlling the optical sensor to the recovery side of the failure state.

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