Control apparatus, control method, and storage medium

Abstract

To provide a control device capable of suitably measuring a peripheral environment even when a detection range of an external sensor varies due to an accident or the like.SOLUTION: A control device 6 acquires an output signal from a lidar unit 7 capable of detecting a feature existing around a vehicle, and calculates a reference angle θ tag indicating an inclination angle of the feature recognized based on the output signal of the lidar unit 7 with respect to a detection range of the lidar unit 7. Then, the control device 6 controls the detection range of the lidar unit 7 based on the reference angle θ tag and the inclination information stored in the storage unit 2 and indicating the angle of the feature with respect to the road surface.SELECTED DRAWING: Figure 13

Description

[Technical Field]

[0001] The present invention relates to a technique for adjusting an illumination unit for object detection. [Background technology]

[0002] Conventionally, there has been known a technique for using measurement results by taking into account errors that occur in a measurement unit due to misalignment, etc. For example, Patent Document 1 discloses a mobile body that includes a sensor that measures the position of an object in a measurement area where an object that needs to be measured during vehicle travel is present, and a control device that corrects errors caused by misalignment of the sensor mounting angle to control the movement of the vehicle body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-221957 Summary of the Invention [Problem to be solved by the invention]

[0004] In autonomous driving, it is necessary to recognize the vehicle's surrounding environment using external sensors such as lidar. However, if the alignment of the external sensors is misaligned due to an accident or other reason, the results of the external sensors' recognition of the surrounding environment will contain errors, resulting in a problem of reduced reliability of the external sensors.

[0005] The present invention has been made to solve the above-mentioned problems, and its main purpose is to provide a control device that can suitably measure the surrounding environment even if the detection range of the external sensor changes due to an accident or the like. [Means for solving the problem]

[0006] The invention described in the claims is a control device comprising a first acquisition unit that acquires an output signal from a detection device that can detect features present around a moving body, a second acquisition unit that acquires first information regarding the inclination of the feature recognized based on the output signal of the detection device relative to the detection range of the detection device, and a control unit that controls the detection range of the detection device based on the first information and second information regarding the angle of the feature relative to the road surface stored in a memory unit.

[0007] The invention described in the claims is a control method executed by a control device, comprising: a first acquisition step of acquiring an output signal from a detection device capable of detecting features present around a moving body; a second acquisition step of acquiring first information regarding the inclination of the feature recognized based on the output signal of the detection device relative to the detection range of the detection device; and a control step of controlling the detection range of the detection device based on the first information and second information regarding the angle of the feature relative to the road surface stored in a memory unit.

[0008] Furthermore, the invention described in the claims is a program executed by a computer, characterized in that it causes the computer to function as a control unit that controls the detection range of the detection device based on a first acquisition unit that acquires an output signal from a detection device that can detect features present around a moving body, a second acquisition unit that acquires first information regarding the inclination of the feature recognized based on the output signal of the detection device relative to the detection range of the detection device, and the first information and second information regarding the angle of the feature relative to the road surface stored in a memory unit. [Brief explanation of the drawings]

[0009] [Figure 1] 1 shows a schematic configuration of a measurement system. [Figure 2] FIG. 2 is a block diagram schematically illustrating the processing of a control device. [Figure 3] 1 shows a block diagram of a rider unit. [Figure 4] An example of scanner placement is shown below. [Figure 5] 1 shows a schematic configuration example of an optical transceiver unit. [Figure 6] The three-axis coordinate system detected by the three-axis sensor installed in the scanner housing is shown. [Figure 7] The positional relationship between the scannable range and the actual scanning range is shown. [Figure 8] 10 is a flowchart showing the procedure of an alignment process. [Figure 9] 10 is a flowchart showing a processing procedure during automatic driving. [Figure 10] 10 shows an example of a data structure of a map DB according to a second embodiment. [Figure 11] FIG. 10 is a diagram showing the relationship between features and tilt angles indicated by tilt information of the feature information. [Figure 12] FIG. 1 is a diagram showing the correspondence between the actual scanning range of a scanner and the scenery that overlaps the actual scanning range. [Figure 13] 10 is a flowchart showing a processing procedure for calibration based on a feature according to a second embodiment. [Figure 14] 10 shows the data structure of a map DB according to a third embodiment. [Figure 15] 10 is a system configuration example according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0010] According to a preferred embodiment of the present invention, a control device includes a first acquisition unit that acquires an output signal from a detection device that can detect features present around a mobile object, a second acquisition unit that acquires first information regarding the inclination of the feature recognized based on the output signal of the detection device with respect to the detection range of the detection device, and a control unit that controls the detection range of the detection device based on the first information and second information regarding the angle of the feature with respect to the road surface that is stored in a memory unit. According to this aspect, the control device can preferably identify a deviation of the detection range of the detection device based on the first information regarding the measured inclination of the feature and the second information regarding the inclination of the feature that is stored in the memory unit, and can accurately adjust the detection range.

[0011] In one aspect of the control device, the first information is information about an angle between a line indicating the detection range of the detection device and a predetermined portion indicating the contour of the feature recognized based on the output signal, and the second information is information about an inclination angle of the predetermined portion constituting the contour of the feature with respect to the road surface. According to this aspect, the control device can identify a deviation of the detection range of the detection device based on the inclination of the predetermined portion indicating the contour of the feature and appropriately adjust the detection range.

[0012] In another aspect of the control device, the first information is information about the angle between a line indicating the detection range of the detection device and a line indicating the symmetry axis of the contour of the feature recognized based on the output signal, and the second information is information about the inclination angle of the line with respect to the road surface. According to this aspect, the control device can identify a deviation of the detection range of the detection device based on the inclination of the line passing through the center of gravity of the feature and appropriately adjust the detection range.

[0013] In another aspect of the control device, the control unit controls the detection range of the detection device based on first information on the inclination of features that are perpendicular to the road surface with respect to the detection range, among features recognized based on the output signal of the detection device, and second information on the angle of the feature with respect to the road surface. In this aspect, the control device identifies a deviation of the detection range of the detection device for features whose inclination is relatively easy to measure, and can therefore more accurately adjust the detection range.

[0014] In another aspect of the control device, the control unit controls the detection range of the detection device based on first information on the inclination of features that do not vary depending on the environment, among features recognized based on the output signal of the detection device, with respect to the detection range, and second information on the angle of the feature with respect to the road surface. In this aspect, the control device identifies a deviation of the detection range of the detection device for features that are less likely to cause measurement errors when measuring the inclination, and can therefore more accurately adjust the detection range.

[0015] According to another preferred embodiment of the present invention, there is provided a control method executed by a control device, the control method comprising: a first acquisition step of acquiring an output signal from a detection device capable of detecting features present around a mobile body; a second acquisition step of acquiring first information regarding the inclination of the feature recognized based on the output signal of the detection device with respect to the detection range of the detection device; and a control step of controlling the detection range of the detection device based on the first information and second information regarding the angle of the feature with respect to the road surface stored in a memory unit. By executing this control method, the control device can preferably identify a deviation in the detection range of the detection device and accurately adjust the detection range.

[0016] According to yet another preferred embodiment of the present invention, a computer-executable program causes the computer to function as a first acquisition unit that acquires an output signal from a detection device capable of detecting features present around a moving object, a second acquisition unit that acquires first information regarding the inclination of the feature recognized based on the output signal of the detection device with respect to the detection range of the detection device, and a control unit that controls the detection range of the detection device based on the first information and second information regarding the angle of the feature with respect to the road surface stored in a memory unit. By executing this program, the computer can preferably identify a deviation in the detection range of the detection device and accurately adjust the detection range. Preferably, the program is stored in a storage medium. [Example]

[0017] First to third preferred embodiments of the present invention will be described below with reference to the drawings.

[0018] <First Example> [Overall configuration] 1 shows a schematic configuration of a measurement system 100 according to a first embodiment. The measurement system 100 is a system that performs measurements for autonomous driving of a vehicle (not shown), and mainly comprises an input unit 1, a storage unit 2, a sensor unit 3, a notification unit 4, a communication unit 5, and a control unit 6. The control unit 6 and other elements are configured to be able to communicate data based on a predetermined communication protocol.

[0019] The input unit 1 is a button, a touch panel, a remote controller, a voice input device, or the like that is operated by the user, and receives various inputs such as switching between automatic and manual driving, and whether or not calibration, which will be described later, needs to be performed.

[0020] The storage unit 2 stores programs executed by the control device 6 and information necessary for the control device 6 to execute predetermined processes. In this embodiment, the storage unit 2 stores a map DB 20. The map DB 20 may be used for navigation when the vehicle is being manually driven, or may be used for driving control of the vehicle when the vehicle is being automatically driven. The map DB 20 includes road data, facility information, and feature information related to features to be detected by the lidar unit 7 (described later). The storage unit 2 also stores alignment information "IA" that records the positioning angle of the lidar unit 7 (described later) relative to the vehicle after alignment, etc. The "alignment" refers to adjustments made to the lidar unit 7 when the lidar unit 7 is manufactured or when the lidar unit 7 is attached to the vehicle.

[0021] The sensor unit 3 is composed of internal sensors that detect the state of the vehicle and external sensors that recognize the environment around the vehicle. The sensor unit 3 includes a Lidar (Light Detection and Ranging, or Laser Illuminated Detection and Ranging) unit 7, an attitude sensor 8, and an impact sensor 9.

[0022] As will be described later, the rider unit 7 has a plurality of scanning units (scanners) installed in different orientations. An example configuration of the rider unit 7 will be described later with reference to FIGS. 3 to 5. The rider unit 7 functions as a detection device having a predetermined detection range. The attitude sensor 8 is a sensor such as a three-axis acceleration sensor or a strain gauge, and is provided as a sensor for detecting the attitude of the rider unit 7. Note that the attitude sensor 8 may be provided in the rider unit 7, or may be further provided in the vehicle as a sensor for detecting the attitude of the vehicle. The impact sensor 9 is a sensor that detects an impact to the vehicle, and may be an acceleration sensor or a sensor that generates an airbag opening signal based on the impact. Note that the impact sensor 9 may be provided in the rider unit 7.

[0023] The notification unit 4 is, for example, a display, a speaker, or the like that performs output under the control of the control device 6. The communication unit 5 performs data communication with an external device under the control of the control device 6.

[0024] The control device 6 includes a CPU that executes a program and controls the entire measurement system 100. In this embodiment, when the control device 6 determines that the LIDAR unit 7 is out of alignment or the like based on the output of the sensor unit 3, such as the attitude sensor 8, the control device 6 calibrates the LIDAR unit 7 or switches to manual driving. Here, "calibration" refers to adjustments made to the LIDAR unit 7 after the LIDAR unit 7 is attached to the vehicle. The control device 6 may be an ECU (Electronic Control Unit) that automatically controls vehicle driving, or may be a CPU of an on-board device that sends a control signal to the ECU to switch between automatic driving and manual driving. In another example, the control device 6 may be configured as a part of the LIDAR unit 7. The control device 6 may also perform highly accurate vehicle position estimation based on the output of the sensor unit 3 and the map DB 20.

[0025] [Function Block] 2 is a block diagram schematically illustrating the processing of the control device 6 in Example 1. As shown in FIG.

[0026] The detection unit 61 acquires a detection signal from the attitude sensor 8 provided in the rider unit 7 as measurement information indicating the current arrangement angle of each scanner in the rider unit 7. The detection unit 61 then detects misalignment of the rider unit 7 by referring to alignment information IA indicating the arrangement angle of each scanner at the time of alignment stored in the memory unit 2 and comparing it with the above-mentioned measurement information. The detection unit 61 also acquires, from the impact sensor 9, a detection signal generated by the impact sensor 9 when vibration of a predetermined level or greater occurs in the vehicle, as information about an impact on the vehicle. The detection unit 61 then transmits information regarding the direction and amount (angle) of the detected misalignment of the rider unit 7 to the control unit 62 when, for example, the detection unit 61 detects misalignment of the rider unit 7 based on the measurement information from the attitude sensor 8 or when it receives impact information from the impact sensor 9.

[0027] In this way, in this embodiment, when the rider unit 7 adjusted by alignment becomes misaligned due to an accident, the control device 6 calibrates the rider unit 7 to suppress deviations in the measurement range of the rider unit 7 and maintain a favorable state in which automatic driving can continue.

[0028] [Example of rider unit configuration] Next, an example configuration of the LIDAR unit 7 will be described. FIG. 3 shows a block diagram of the LIDAR unit 7. The LIDAR unit 7 is a Time Of Flight (TOF) LIDAR that measures distances to and detects objects present around the vehicle. The LIDAR unit 7 is used, for example, as part of an advanced driver assistance system to assist in recognizing the vehicle's surrounding environment. The LIDAR unit 7 mainly includes multiple scanners (L1 to L4, ...), multiple optical transmitters and receivers (TR1 to TR4, ...), and a signal processor SP. In the following description, when the scanners (L1 to L4, ...) are not distinguished from one another, they will simply be referred to as "scanner L," and when the optical transmitters and receivers (TR1 to TR4, ...) are not distinguished from one another, they will simply be referred to as "optical transmitters and receivers TR."

[0029] The scanner L emits laser pulses (hereinafter also referred to as "transmitted light pulses") within a predetermined range of horizontal and vertical angles. The scanner L emits transmitted light pulses for each segment obtained by dividing the horizontal angle by equal angles. The optical transceiver TR then receives reflected light of the transmitted light pulses (hereinafter also referred to as "received light pulses") within a predetermined period after emitting the transmitted light pulses, and outputs a signal (hereinafter also referred to as a "segment signal Sseg") related to the received light intensity for each segment to the signal processor SP. The signal processor SP outputs point cloud information indicating a set of the distance to each point on the object irradiated with the transmitted light pulse and the angle of the object, based on the segment signal Sseg for each segment received from the optical transceiver TR.

[0030] In this embodiment, the scanner L and the optical transmitter / receiver TR are housed in a scanner housing section 50 (50a to 50c, ...). The scanner housing section 50 houses one or more pairs of scanners L and optical transmitter / receivers TR. In the example of FIG. 3, the scanner housing section 50a houses the scanner L1 and the optical transmitter / receiver TR1, the scanner housing section 50b houses the scanners L2 and L3 and the optical transmitter / receivers TR2 and TR3, and the scanner housing section 50c houses the scanner L4 and the optical transmitter / receiver TR4. Each of the scanner housing sections 50 is provided with a posture sensor 8 (8a to 8c, ...) for detecting the posture of the scanner housing section 50 and an adjustment mechanism 10 (10a to 10c, ...) for adjusting the orientation of the scanner housing section 50.

[0031] The attitude sensors 8 (8a to 8c, ...) are sensors used to detect misalignment of each scanner housing section 50, and transmit a detection signal to the control device 6. The adjustment mechanism 10 includes, for example, an actuator, and adjusts the orientation of the scanner housing section 50 based on a control signal received from the control device 6. Note that the attitude sensor 8 and adjustment mechanism 10 shown in FIG. 3 may be provided for each scanner L instead of for each scanner housing section 50.

[0032] FIG. 4 shows an example of the arrangement of the individual scanners L of the lidar unit 7. In FIG. 4, hatched sector-shaped areas indicate the scanning range of the transmitted light pulses emitted by the corresponding scanner L. In the example of FIG. 4, 12 scanners L (L1 to L12) are provided on the vehicle, with scanners L1 to L4 oriented so that their scanning range is the front of the vehicle, and scanners L5 and L6 oriented so that their scanning range is the left side of the vehicle. Scanners L7 and L8 are also oriented so that their scanning range is the right side of the vehicle, and scanners L9 to L12 oriented so that their scanning range is the rear of the vehicle.

[0033] Fig. 5 shows a schematic configuration example of the optical transmitter / receiver unit TR. As shown in Fig. 5, the optical transmitter / receiver unit TR mainly includes a synchronization control unit 11, an LD driver 12, a laser diode 13, a motor control unit 15, a light receiving element 16, a current-voltage conversion circuit (transimpedance amplifier) ​​17, an A / D converter 18, a segmentator 19, and a crystal oscillator 20.

[0034] The crystal oscillator 20 outputs a pulsed clock signal "S1" to the synchronization control unit 11 and the A / D converter 18. The synchronization control unit 11 outputs a pulsed trigger signal "S2" to the LD driver 12. The synchronization control unit 11 also outputs a segment extraction signal "S3" to the segmentator 19, which determines the timing at which the segmentator 19 extracts the output of the A / D converter 18, as will be described later.

[0035] The LD driver 12 supplies a pulse current to the laser diode 13 in synchronization with a trigger signal S2 input from the synchronization control unit 11. The laser diode 13 is, for example, an infrared pulse laser, and emits an optical pulse based on the pulse current supplied from the LD driver 12.

[0036] The scanner L is configured as a scanner including, for example, a transmitting and receiving optical system, and scans the transmitted light pulse emitted by the laser diode 13, and also guides the received light pulse, which is the return light reflected from the object onto which the emitted transmitted light pulse is irradiated, to the light receiving element 16. In this embodiment, the scanner L includes a motor for rotation. In this way, the scanner L functions as an irradiation unit that irradiates electromagnetic waves.

[0037] The light receiving element 16 is, for example, an avalanche photodiode, and generates a weak current corresponding to the light intensity of the light reflected from the object guided by the scanner L, i.e., the received light pulse. The light receiving element 16 supplies the generated weak current to a current-voltage conversion circuit 17. The current-voltage conversion circuit 17 amplifies the weak current supplied from the light receiving element 16 and converts it into a voltage signal, and inputs the converted voltage signal to an A / D converter 18.

[0038] The A / D converter 18 converts the voltage signal supplied from the current-voltage conversion circuit 17 into a digital signal based on the clock signal S1 supplied from the crystal oscillator 20, and supplies the converted digital signal to the segmentator 19. The segmentator 19 generates the digital signal that is the output of the A / D converter 18 during the period in which the segment extraction signal S3 is asserted as a segment signal Sseg. The segmentator 19 supplies the generated segment signal Sseg to the signal processing unit SP.

[0039] The signal processing unit SP generates point cloud information indicating the distance and angle of the object for each optical transceiver unit TR based on the segment signals Sseg transmitted from each optical transceiver unit TR. Specifically, the signal processing unit SP detects peaks from the waveform of the segment signals Sseg and estimates the amplitude and delay time corresponding to the detected peaks. The signal processing unit SP then generates, as information for each point constituting the point cloud information, a set of distance information corresponding to the delay time of a peak whose estimated amplitude is equal to or greater than a predetermined threshold, among the peaks of the waveform indicated by the segment signals Sseg, and angle information corresponding to the target segment.

[0040] [Alignment processing] Next, an alignment process, which is an adjustment process performed on the rider unit 7 when the rider unit 7 is manufactured or when the rider unit 7 is attached to a vehicle, will be described.

[0041] The point cloud information generated based on the received optical pulses received by each optical transmitter / receiver TR via each scanner L is information expressed in a local coordinate system based on the orientation and position of each scanner L, and depends on the relative position (specifically, the placement position and placement angle) of each scanner L with respect to the vehicle. Therefore, after aligning each scanner L with the vehicle, the measurement system 100 generates alignment information IA that indicates the placement position and placement angle of each scanner L with respect to the vehicle after alignment, and stores this in the memory unit 2.

[0042] As a result, for example, when the vehicle is traveling, the control device 6 or the signal processing unit SP can convert the coordinate system of the point cloud information obtained for each scanner L into a common coordinate system based on the vehicle by referring to the alignment information IA stored in the memory unit 2, and can also convert it into an absolute coordinate system based on latitude, longitude, and altitude by using the vehicle's position information and orientation information. Also, in this embodiment, as will be described later, the control device 6 refers to the alignment information IA to preferably detect alignment deviation of the scanner housing unit 50.

[0043] [Accident detection processing] When it is estimated that a vehicle accident will occur, the control device 6 determines that calibration of the LIDAR unit 7 is necessary. Here, the vehicle accident detection process will be described.

[0044] (1) Detection based on reference angle If the placement angle of the scanner storage unit 50 or scanner L relative to the vehicle indicated by the alignment information IA stored in the memory unit 2 (also called the "reference angle") differs from the current placement angle of the scanner storage unit 50 or scanner L relative to the vehicle measured by the attitude sensor 8 (also called the "latest measured angle"), the control unit 6 determines that an accident has occurred, causing an alignment shift in the scanner storage unit 50 or scanner L.

[0045] Here, when calculating the latest measured angle, the control device 6 performs a process to cancel the inclination of the vehicle itself. Specifically, the control device 6 calculates the latest measured angle excluding the influence of the inclination of the vehicle itself by correcting the angle measured by the attitude sensor 8 installed in the scanner housing unit 50 by the vehicle inclination angle measured by the attitude sensor 8 or the like installed on the vehicle. Note that the control device 6 may recognize the inclination angle of the vehicle itself based on the inclination information of road data registered in the map DB 20 and calculate the latest measured angle. In this case, the control device 6 acquires inclination information of the road to which the current position belongs from the map DB 20 based on the vehicle position information recognized from the output of the sensor unit 3.

[0046] FIG. 6(A) shows a three-axis (X, Y, Z) coordinate system detected by the attitude sensor 8 installed in the scanner housing unit 50 when there is no misalignment. In the example of FIG. 6(A), the vehicle is placed on a horizontal surface, and the attitude sensor 8 detects acceleration on each of the X, Y, and Z axes. Here, the "X axis" indicates the front direction of the scanner housing unit 50 (i.e., the laser emission direction), the "Y axis" indicates the left and right lateral directions of the scanner housing unit 50, and the "Z axis" indicates the height direction of the scanner housing unit 50. When there is no misalignment, the X and Y axes are approximately perpendicular to the gravitational acceleration, and the Z axis is approximately parallel to the gravitational acceleration.

[0047] Fig. 6(B) is a diagram showing a change in the orientation of the scanner housing unit 50 when the scanner housing unit 50 in Fig. 6(A) becomes misaligned due to an impact caused by an accident, etc. In Fig. 6(B), the solid XYZ coordinate axes indicate the three coordinate axes detected by the attitude sensor 8 installed on the tilted scanner housing unit 50, and the dashed-dotted XYZ coordinate axes indicate the three coordinate axes before the scanner housing unit 50 shown in Fig. 6(A) was tilted.

[0048] In the example of FIG. 6(B), the scanner housing unit 50 tilts from the state shown in FIG. 6(A), causing the measurement values ​​of the three axes of the attitude sensor 8 to differ by amounts corresponding to the X-axis deviation (see arrow A1), Y-axis deviation (see arrow A2), and Z-axis deviation (see arrow A3) before and after the tilt of the scanner housing unit 50. Thus, if misalignment of the scanner housing unit 50 occurs due to an accident or the like, a deviation (rotational deviation) in the placement angle of the scanner housing unit 50 occurs, and the measurement values ​​of the attitude sensor 8 change depending on the deviation before and after the misalignment. Taking the above into consideration, in this embodiment, the control device 6 compares, for each scanner housing unit 50, the reference angle indicated by the alignment information IA with the most recently measured angle based on the output of the attitude sensor 8 for each rotational direction (e.g., the roll direction around the X-axis, the pitch direction around the Y-axis, and the yaw direction around the Z-axis). If a rotational direction in which a deviation of a predetermined angle or more occurs exists, it is estimated that misalignment of the scanner housing unit 50 has occurred due to an accident or the like.

[0049] It should be noted that, in the case of an alignment shift that does not involve a change in the placement angle (i.e., a positional shift along the X-axis, Y-axis, and / or Z-axis), the measurement value of the attitude sensor 8 does not change before and after the shift. On the other hand, if a shift occurs in the scanner housing unit 50 due to an impact from an accident or the like, it is expected that a shift in the placement angle will inevitably occur in addition to a positional shift. Therefore, in this embodiment, the control device 6 detects a shift in the placement angle of the scanner housing unit 50 to determine whether calibration is required.

[0050] (2) Detection by other methods Similarly, when the control device 6 detects an abnormality using any of the methods (the second and third methods) described below instead of the alignment deviation detection process based on the alignment information IA described above, it may assume that there has been an alignment deviation in the scanner accommodating section 50 due to an accident and determine that the calibration process described below should be performed.

[0051] In the second method, when the control device 6 determines based on the output of the impact sensor 9 provided in the vehicle that an impact of a predetermined level or greater has occurred to the vehicle, it determines that there is a high possibility that the scanner housing unit 50 has become misaligned due to the accident, and that a calibration process, described below, is necessary. For example, as described in FIG. 2, the control device 6 determines that an impact has occurred to the vehicle when it receives impact information from the impact sensor 9 indicating that an impact of a predetermined level or greater has occurred. This also allows the control device 6 to preferably detect the occurrence of misalignment of the scanner housing unit 50.

[0052] In the third method, when an error occurs in the object recognition process, the control device 6 determines that there is a high possibility that the scanner housing 50 has become misaligned due to an accident, and that a calibration process (described later) is necessary. For example, when the road surface recognized by combining point cloud information generated based on the received light pulses of each scanner L is distorted, that is, when the inclination angle differs for each road surface indicated by the point cloud information for each scanner L, the control device 6 determines that at least one of the scanners L has become misaligned.

[0053] In another example based on the third method, the control device 6 compares the point cloud information for the overlapping scanning ranges of the scanners L, and if there is a deviation in the position of the point cloud indicated by the compared point cloud information, determines that there is an alignment deviation in at least one of the scanners L whose scanning ranges overlap.

[0054] In yet another example based on the third method, when the accuracy of the vehicle's position information is sufficiently high, the control device 6 converts the position information of a specific feature registered in the map DB 20 and the point cloud information that includes the feature in its scanning range into the same coordinate system based on the vehicle's position information, and compares them. Then, when there is a discrepancy between the position indicated by the position information of the feature and the position of the feature indicated by the point cloud information, the control device 6 determines that there is an alignment error in the scanner L that scanned the feature.

[0055] In yet another example based on the third method, the control device 6 compares the position of an object recognized based on an image output by a camera included in the sensor unit 3 with the position of the same object recognized based on point cloud information output by the LIDAR unit 7. If the compared position of the object deviates by a predetermined amount or more, the control device 6 determines that there is a high possibility that the scanner housing unit 50 has become misaligned due to an accident and that calibration processing is necessary. In this case, the control device 6 may measure the three-dimensional position of the object based on the outputs of multiple cameras and compare the measured three-dimensional position with the three-dimensional position based on the point cloud information output by the LIDAR unit 7.

[0056] [Calibration process] Next, a calibration process that is executed when the alignment of the rider unit 7 is shifted due to a vehicle accident will be described.

[0057] As a calibration process, the control device 6 performs at least one of electronic adjustment to change the actual scanning range, which will be described later, or physical adjustment by controlling the adjustment mechanism 10 provided in each scanner housing unit 50. Note that as a pre-processing step for the calibration process, the control device 6 calculates the difference for each direction between the reference angle of each scanner housing unit 50 indicated by the alignment information IA stored in the memory unit 2 and the latest measured angle indicated by the measurement information output by the attitude sensor 8 of each scanner housing unit 50, thereby identifying the alignment deviation (i.e., the direction and amount of deviation) of each scanner housing unit 50.

[0058] Here, a specific example of the above-mentioned electronic adjustment will be described. Fig. 7(A) shows the correspondence relationship between the scannable range "SR" of a certain scanner L and the actual scanning range "FOV" on a virtual irradiation plane perpendicular to the emission direction of the scanner L before the calibration process is performed. Here, the scannable range SR refers to the range where scanning by the transmitted light pulses is possible, and the actual scanning range FOV refers to the range where scanning by the transmitted light pulses is actually performed. Note that the arrow in the actual scanning range FOV indicates an example of the scanning direction.

[0059] As shown in FIG. 7(A), the actual scanning range FOV is moved within the scannable range SR based on the direction and amount of deviation from the scannable range.

[0060] FIG. 7B shows the correspondence between the scannable range SR and the actual scanning range FOV after the electronically adjusted scan range SR of the scanner L is set to a range smaller than the scan range SR of the scanner L. The control device 6 performs the electronic alignment adjustment. In the example of FIG. 7B, the control device 6 transmits a control signal instructing a change in the parameters of the internal signals of the optical transceiver TR based on the direction and amount of misalignment of the scanner housing unit 50 that houses the scanner L. This causes the control device 6 to move the actual scanning range FOV a predetermined distance in the upper left direction (see arrow 55). In this case, the control device 6 may, for example, store in advance in the storage unit 2 a map or the like for each scanner L that indicates the direction and width of movement of the actual scanning range FOV depending on the misalignment of each scanner housing unit 50, and generate the above-mentioned control signal based on the direction and width of movement of the actual scanning range FOV determined by referring to the map. As a result, the control device 6 suitably adjusts the current scanning range of the LIDAR unit 7 so that it is equivalent to the scanning range of the LIDAR unit 7 immediately after the alignment process (that is, before the occurrence of misalignment).

[0061] In this way, by moving the actual scanning range FOV based on electronic adjustment, the control device 6 can effectively suppress a decrease in the accuracy of the object recognition processing using the LIDAR unit 7, and continue automatic driving control, even if an alignment shift occurs due to an accident or the like.

[0062] Furthermore, instead of the electronic adjustment described above, the control device 6 may perform physical adjustment to move the actual scanning range FOV by controlling the adjustment mechanism 10 of the scanner housing unit 50. In this case, for example, each scanner housing unit 50 is rotatable in the roll direction, pitch direction, and yaw direction, and the adjustment mechanism 10 adjusts the angle of the corresponding scanner housing unit 50 in any rotation direction based on a control signal supplied from the control device 6.

[0063] Therefore, when performing the above-mentioned physical adjustment, the control device 6 generates a control signal to be sent to the adjustment mechanism 10 based on the identified direction and amount of misalignment of the scanner housing unit 50 so that the actual scanning range FOV is substantially the same before and after the alignment error. In this case, for example, a map indicating the relationship between the direction and amount of misalignment of the scanner housing unit 50 and the direction and amount of movement of the scanner housing unit 50 (for example, directions around the X, Y, and Z axes in FIG. 6) is stored in advance in the storage unit 2. Then, the control device 6 generates a control signal for the adjustment mechanism 10 of the scanner housing unit 50 where alignment error has occurred by referring to the map.

[0064] Preferably, when the control device 6 determines that the actual scanning range FOV cannot be adjusted to be equivalent to the scanning range of the lidar unit 7 immediately after the alignment process (i.e., before the occurrence of alignment deviation) using only the above-mentioned electronic adjustment, the control device 6 adjusts the position of the scanner accommodating section 50 based on the control of the adjustment mechanism 10.

[0065] Furthermore, if the misalignment of the scanner housing 50 is so great that neither the electronic nor physical adjustment described above can adjust the actual scanning range FOV to be the same before and after the misalignment, the control device 6 does not perform the calibration process. In this case, instead of performing the calibration process, the control device 6 causes the notification unit 4 to output an output prompting or warning the driver to switch to manual driving, or to output a warning that an error has occurred. In this case, the control device 6 switches the vehicle's driving mode from autonomous driving to manual driving, for example, when it detects a user input instructing the driver to switch to manual driving, or after a predetermined time has elapsed since the above-mentioned warning. This prevents the control device 6 from continuing autonomous driving in a situation where the accuracy of the recognition process using the lidar unit 7 is low, thereby ensuring safety.

[0066] [Processing flow] Next, the alignment process that is performed before the vehicle is shipped and the process that is performed during autonomous driving after the vehicle is shipped will be described with reference to the flowcharts of FIGS.

[0067] (1) Alignment Processing Fig. 8 is a flowchart showing the procedure of the alignment process of the LIDAR unit 7. The measurement system 100 executes the process of the flowchart shown in Fig. 8 when installing each scanner L on the vehicle. Note that the alignment process is performed with the vehicle placed on a horizontal surface.

[0068] First, the scanner housing units 50 housing the scanners L are fitted into predetermined positions in the vehicle, and the alignment of each scanner housing unit 50 is adjusted (step S101). In this case, for example, the control device 6 adjusts the angle of at least one of the pitch, yaw, and roll directions of the scanner housing units 50 by sending a control signal to the adjustment mechanism 10 of the scanner housing unit 50 that requires position adjustment, based on an input to the input unit 1, etc. In another example, the alignment of each scanner housing unit 50 may be adjusted manually.

[0069] Then, the measurement information output by the attitude sensor 8 provided in each scanner housing section 50 after the alignment adjustment in step S101 is stored in the memory section 2 as alignment information IA indicating the reference angle of each scanner housing section 50 (step S103).

[0070] (2) Processing during autonomous driving 9 is an example of a flowchart showing a processing flow executed by the control device 6 during automatic driving. The control device 6 repeatedly executes the processing of the flowchart in FIG. 9, for example, according to a predetermined cycle.

[0071] First, the control device 6 determines whether or not an object recognition error has occurred (step S201). In this case, the control device 6 determines whether or not there is any deviation or the like in the point cloud information obtained for each scanner L, based on the third method described in the [Accident Detection Processing] section. Then, if an object recognition error has occurred (step S201; Yes), the control device 6 proceeds to step S204.

[0072] On the other hand, if an object recognition error has not occurred (step S201; No), the control device 6 determines whether or not an impact that is estimated to be an accident has been detected (step S202). In this case, the control device 6 determines whether or not the value indicated by the impact information output by the impact sensor 9 temporarily exceeds a predetermined threshold value, based on the second method described in the [Accident Detection Processing] section. Then, if the control device 6 detects an impact that is estimated to be an accident (step S202; Yes), the control device 6 proceeds to step S204.

[0073] On the other hand, if the above-mentioned impact is not detected (step S202; No), the control device 6 determines whether or not an angle deviation has been detected in which the amount of deviation between the reference angle indicated by the alignment information IA and the latest measured angle detected by the attitude sensor 8 is equal to or greater than a predetermined amount (step S203). If the control device 6 detects the above-mentioned angle deviation (step S203; Yes), the control device 6 proceeds to the process of step S204. On the other hand, if the above-mentioned angle deviation is not detected (step S203; No), the control device 6 determines that no alignment deviation has occurred in the rider unit 7, and ends the process of the flowchart.

[0074] Next, if the control device 6 detects an abnormality in any of steps S201 to S203, it recognizes the direction and amount of the angular deviation between the reference angle and the most recently measured angle (step S204). Then, the control device 6 determines whether or not it is possible to adjust the actual scanning range FOV so as to compensate for the above-mentioned angular deviation through calibration processing (step S205). For example, the control device 6 stores in advance in the storage unit 2 information on the range of angular deviation that can be adjusted through electronic adjustment or physical adjustment described in the [Calibration Processing] section, and determines whether or not it is possible to adjust the actual scanning range FOV through calibration processing by referring to the information on the above-mentioned range.

[0075] If the control device 6 determines that the actual scanning range FOV can be adjusted to compensate for the angular misalignment through the calibration process (step S205; Yes), the control device 6 causes the notification unit 4 to output a guide regarding the execution of the calibration process (step S206). For example, the control device 6 outputs a message indicating that automatic operation can be continued by executing the calibration process, and also causes the notification unit 4 to output a message prompting the user to select whether or not to execute the calibration process. If the control device 6 detects an input indicating that the calibration process should be executed (step S207; Yes), the control device 6 executes the calibration process (step S208). In this case, for example, if the actual scanning range FOV can be adjusted electronically to compensate for the angular misalignment, the control device 6 adjusts the actual scanning range FOV through electronic adjustment. If the angular misalignment cannot be compensated for by electronic adjustment alone, the control device 6 adjusts the actual scanning range FOV by physically adjusting the scanner housing unit 50 under the control of the adjustment mechanism 10. If the calibration process is successful (step S209; Yes), the control device 6 ends the processing of the flowchart. In this case, the control device 6 continues to control the automatic driving.

[0076] On the other hand, if the calibration process cannot adjust the actual scanning range FOV to compensate for the angle deviation (step S205; No), or if there is no input indicating that the calibration process should be performed (step S207; No), or if the calibration process is not successful (step S209; No), the control device 6 displays a predetermined warning and / or switches to manual driving (step S210). In this case, the control device 6 outputs a message indicating that automatic driving cannot be continued or a message urging the user to manually switch to manual driving, or automatically switches to manual driving after the above-mentioned message. As a result, the control device 6 can urge the user to smoothly switch to manual driving when the reliability of the rider unit 7 has decreased, thereby suitably suppressing a decrease in safety.

[0077] As described above, the control device 6 according to the first embodiment functionally includes a detection unit 61 and a control unit 62. The detection unit 61 detects a change in the placement angle of the scanner L, which irradiates electromagnetic waves toward the outside of the vehicle, based on alignment information IA generated during alignment and measurement information related to the LIDAR unit 7 received from the attitude sensor 8. The control unit 62 then controls the irradiation direction of the scanner L based on the detection result of the detection unit 61. As a result, even if an alignment error occurs in the LIDAR unit 7 due to an accident or the like, the control device 6 can calibrate the LIDAR unit 7 to preferably maintain a state in which autonomous driving can continue.

[0078] <Second Example> The second embodiment differs from the first embodiment in that the control device 6 performs calibration based on the detection result of the deviation of the actual scanning range FOV based on the tilt of the detected feature, instead of or in addition to performing calibration based on the deviation between the reference angle indicated by the alignment information IA and the latest measured angle measured by the attitude sensor 8. Hereinafter, components similar to those in the first embodiment will be denoted by the same reference numerals as appropriate, and their description will be omitted.

[0079] FIG. 10 shows an example of the data structure of the map DB 20 according to the second embodiment. As shown in FIG. 10, the map DB 20 includes not only road data but also feature information about features around the roads. The feature information is information registered for each feature, and includes type information, location information, and slope information. Note that by using a map DB including such feature information, vehicle navigation during manual driving and advanced vehicle driving control during autonomous driving become possible.

[0080] Here, the type information is information that indicates the type of feature, and is referenced, for example, in processes such as determining whether a feature around the vehicle is suitable as a reference feature (also called a "reference feature") when performing calibration. The position information is information that indicates the absolute position of the feature, and is referenced in processes such as specifying the position of the feature relative to the vehicle. The inclination information is information that indicates the inclination angle of the feature from the road surface.

[0081] Here, the inclination information may indicate the angle formed by the contour of the side (including the front and back) of the feature with respect to the road surface, or may indicate the angle formed by the line indicating the axis of symmetry of the contour of the feature (the line passing through the center of gravity of the feature) with respect to the road surface. This will be explained with reference to FIG.

[0082] Figure 11(A) is a diagram showing the relationship between feature A, which has a rectangular outline when observed from the road, and the inclination angle θ indicated by the inclination information of that feature information. In Figure 11(A), feature A has the shape of a prism or cylinder, and the inclination angle θ indicated by the inclination information of the feature information corresponding to feature A is the angle (here, approximately 90 degrees) formed by the outline of the side (including the front and back) of feature A with respect to the road surface.

[0083] FIG. 11(B) is a diagram showing the relationship between feature B, which has an outline that tapers toward the top when observed from the road, and the inclination angle θ indicated by the inclination information of the feature information. In FIG. 11(B), the outline of feature B has a shape with a dashed line 70 as its axis of symmetry. Dashed line 70 is a line that passes through the center of gravity of the outline of feature B and is a line that is approximately parallel to the outline that shows the side of feature B. The inclination angle θ indicated by the inclination information of the feature information corresponding to feature B indicates the angle that dashed line 70 forms with respect to the road surface (approximately 90 degrees in this case). Thus, in the example of FIG. 11(B), information on the overall inclination of feature B is recorded in the feature information as inclination information. In this case, a predetermined flag or the like may be added to the feature information to indicate that the inclination information indicates the inclination angle of the line that passes through the center of gravity of the feature.

[0084] FIG. 11(C) is a diagram showing the relationship between feature C when observed from the road and the inclination angles θ1 and θ2 indicated by the inclination information of the feature information. In FIG. 11(C), feature C has contour lines 71 and 72 forming its side surfaces that form different angles θ1 and θ2 with respect to the road surface. In this case, the feature information corresponding to feature C includes inclination information indicating the inclination angles θ1 and θ2 corresponding to the contour lines 71 and 72. In this case, the feature information may have a data structure that enables identification of the correspondence between the contour lines detected by the lidar unit 7 and the inclination angles recorded in the feature information. For example, the inclination angles may be recorded in the feature information in order of the inclination angles of the contour lines closest to the road.

[0085] The control device 6 refers to feature information including tilt information based on any of the formats described with reference to FIGS. 11A to 11C, and identifies a line (also referred to as a "feature reference line Lo") that approximately connects points forming the tilt angle indicated by the tilt information of the feature information from the point cloud that forms the outline of the reference feature detected by the LIDAR unit 7. Next, the control device 6 calculates the angle between the identified feature reference line Lo and a line (also referred to as an "actual scanning boundary line Lf") that forms any side of the boundary of the rectangular actual scanning range FOV. The control device 6 then detects an alignment deviation of the LIDAR unit 7 based on the angle (also referred to as a "reference angle θtag") formed between the feature reference line Lo and the actual scanning boundary line Lf and the tilt angle indicated by the corresponding tilt information. In this way, the information on the reference angle θtag functions as first information, and the tilt information functions as second information.

[0086] Next, a specific example of a method for detecting misalignment based on the reference angle θtag and the tilt angle indicated by the tilt information will be described with reference to FIG.

[0087] 12A is a diagram showing the correspondence between the actual scanning range FOV of a scanner L before misalignment occurs and the scenery that overlaps with the actual scanning range FOV. In the example of FIG. 12A, when no misalignment occurs, the lateral direction of the actual scanning range FOV of the target scanner L is parallel to the road surface (i.e., the horizon).

[0088] In this case, the control device 6 first extracts a point cloud forming the outline of the feature 60 from the point cloud information generated by the lidar unit 7. Then, the control device 6 projects the point cloud forming the outline of the feature 60 onto the same plane as the actual scanning range FOV, and identifies a point cloud forming the outline of the side of the feature 60 from the point cloud on the plane, thereby recognizing the feature reference line Lo. Note that in this case, for example, the control device 6 may assume that the actual scanning range FOV is a range onto which the transmitted light pulse is irradiated on a virtual irradiation surface that is a predetermined distance away from the vehicle. Furthermore, the control device 6 determines an actual scanning boundary line Lf (here, the bottom side of the actual scanning range FOV) from the boundary line of the actual scanning range FOV, and calculates the reference angle θtag based on the determined actual scanning boundary line Lf and the feature reference line Lo.

[0089] Then, the control device 6 calculates the angle difference between the calculated reference angle θtag (here, 90 degrees) and the tilt angle (here, 90 degrees) indicated by the tilt information of the feature information corresponding to the feature 60. In this case, the above-mentioned angle difference is 0 degrees, so the control device 6 determines that no angle deviation has occurred in the scanner L corresponding to the actual scanning range FOV of the target in the example of Figure 12(A). Therefore, in this case, the control device 6 determines that calibration is not required for the scanner L of the target.

[0090] FIG. 12B is a diagram showing the correspondence between the actual scanning range FOV of the scanner L in which misalignment occurs and the scenery overlapping the actual scanning range FOV.

[0091] In this case, the control device 6 identifies the actual scanning boundary line Lf and the feature reference line Lo by performing the same processing as in Fig. 12(A), and calculates the reference angle θtag formed by the actual scanning boundary line Lf and the feature reference line Lo. The control device 6 then calculates the angular difference (here, 10 degrees) between the calculated reference angle θtag (here, 100 degrees) and the tilt angle of the feature 60 indicated by the referenced tilt information (here, 90 degrees). In this case, the control device 6 determines that an alignment error has occurred in the target scanner L because the above-mentioned angle difference is equal to or greater than a predetermined difference. Therefore, in this case, the control device 6 determines that calibration of the target scanner L is necessary.

[0092] 12C is a diagram showing the correspondence relationship between the actual scanning range FOV after calibration and the scenery overlapping the actual scanning range FOV. In FIG. 12C, a dashed dotted line 61 indicates the position of the actual scanning boundary line Lf before calibration.

[0093] Based on the angle difference, the control device 6 determines that the scanner L corresponding to the target actual scanning range FOV is misaligned by 10 degrees in the roll direction (clockwise). Therefore, in this case, the control device 6 rotates the actual scanning range FOV by 10 degrees in the roll direction (counterclockwise) based on the calibration method described in the "Calibration Process" of the first embodiment. As a result, as shown in FIG. 12(C), the longitudinal direction of the actual scanning range FOV and the road surface become substantially parallel, and the correspondence between them is the same as before the misalignment of the target scanner L occurred (i.e., before the vehicle impact occurred).

[0094] In this way, the control device 6 can determine whether calibration is necessary and perform calibration in an appropriate manner by calculating the reference angle θtag formed by the actual scanning boundary line Lf and the feature reference line Lo. Note that, in a state where there is no alignment deviation, the longitudinal direction of the actual scanning range FOV is not limited to being parallel to the road surface, but may have a predetermined inclination angle with respect to the road surface. In this case, for example, the control device 6 stores information about the inclination angle in advance, and performs calibration and determines whether calibration is necessary by further taking the inclination angle into consideration with respect to the angle difference between the reference angle θtag and the inclination angle indicated by the inclination information.

[0095] Furthermore, when the tilt information of the reference feature represents the tilt angle of a line passing through the center of gravity of the feature, as in the example of Figure 11(B), the control device 6, for example, determines the center of gravity of the point cloud when the point cloud of the reference feature is projected onto the same plane as the actual scanning range FOV, and calculates the feature reference line Lo (e.g., a symmetric line) passing through the determined center of gravity based on a predetermined calculation method. Furthermore, when the tilt information of the reference feature records the tilt angles for multiple contours (see Figure 11(C)), the control device 6 calculates the feature reference line Lo based on at least one tilt angle indicated by the tilt information and point cloud information representing the contour portion corresponding to the tilt angle. In this case, the control device 6 may calculate the feature reference line Lo based on point cloud information of a contour corresponding to a tilt angle close to 90 degrees, for example, or may calculate the feature reference line Lo based on point cloud information of a contour that has been detected as point cloud information.

[0096] Fig. 13 is a flowchart showing the processing procedure for calibration based on a feature according to the second embodiment. The control device 6 repeatedly executes the processing of the flowchart shown in Fig. 13, for example, at a predetermined cycle. The control device 6 may execute the processing of the flowchart shown in Fig. 13 in parallel with the processing of the flowchart of Fig. 9 described in the first embodiment, or may execute it instead of the processing of the flowchart of Fig. 9.

[0097] First, the control device 6 acquires feature information of features present around the vehicle (step S301). In this case, for example, the control device 6 refers to the vehicle position information generated based on the position information of the feature information and the output of the sensor unit 3, and extracts from the map DB 20 feature information of features that are present within the actual scanning range FOV of any of the scanners L and that are within the maximum ranging distance from the vehicle position.

[0098] Next, the control device 6 determines whether or not there is a feature suitable for use as a reference feature (step S302). In this case, for example, the control device 6 refers to the type information included in the feature information acquired in step S301 and determines whether or not there is a fixed object, such as a building, whose outline does not fluctuate due to weather conditions such as wind or other external environmental factors. In another example, the control device 6 determines that a feature estimated to be configured perpendicular to the road surface (e.g., a building, a traffic light pole, a utility pole, etc.) is suitable for use as a reference feature. In this example, the control device 6 may estimate whether or not a feature is configured perpendicular to the road surface based on the type information of the feature information, or may make the above-mentioned determination based on whether or not the inclination angle of the feature's outline, indicated by the inclination information included in the feature information, is approximately 90 degrees.

[0099] If there are features suitable to be used as reference features (step S302; Yes), the control device 6 regards the features as reference features and executes the processes of steps S303 to S306 below. On the other hand, if there are no features suitable to be used as reference features (step S302; No), the control device 6 ends the process of the flowchart.

[0100] Next, the control device 6 calculates, for each reference feature, a feature reference line Lo that forms a line passing through the contour or center of gravity of the feature, based on the point cloud information of each feature (step S303). In this case, the control device 6 extracts a point cloud for each reference feature from the point cloud information obtained from the LIDAR unit 7, for example, based on the position information of the feature, and calculates, for each reference feature, a feature reference line Lo that forms the contour, etc. of the reference feature.

[0101] The control device 6 then identifies an actual scanning boundary line Lf based on the actual scanning range FOV of the scanner L that includes each reference feature in its detection range, relative to the calculated feature reference line Lo for each reference feature, and calculates the reference angle θtag (step S304). The control device 6 then determines whether there is a reference feature for which the angle difference between the tilt angle indicated by the tilt information and the reference angle θtag is equal to or greater than a predetermined angle difference (step S305). The above-mentioned predetermined angle is determined in advance, taking into consideration, for example, the need for calibration based on the angle difference and the calculation error of the reference angle θtag.

[0102] If there is a reference feature where the angular difference between the tilt angle indicated by the tilt information and the reference angle θtag is equal to or greater than a predetermined angular difference (step S305; Yes), the control device 6 determines that there is a deviation in the actual scanning range FOV used to calculate the reference angle θtag, and performs calibration based on the above-mentioned angular difference on the scanner L corresponding to the actual scanning range FOV (step S306). In this case, the control device 6 rotates the actual scanning range FOV of the target by electronic adjustment or physical adjustment under the control of the adjustment mechanism 10 so as to eliminate the above-mentioned angular difference. Note that, similar to the processing of the flowchart of FIG. 9 described in the first embodiment, the control device 6 may provide guidance regarding the execution of calibration before executing the calibration, and may perform the calibration when it detects an input indicating that calibration should be performed.

[0103] On the other hand, if there is no reference feature for which the angular difference between the tilt angle indicated by the tilt information and the reference angle θtag is equal to or greater than the predetermined angle (step S305; No), the control device 6 determines that no alignment deviation of the scanner L is detected and that there is no need to perform calibration. Therefore, in this case, the control device 6 ends the processing of the flowchart without performing calibration.

[0104] As described above, the control device 6 according to the second embodiment acquires output signals from the lidar unit 7 that can detect features present around the vehicle, and calculates the reference angle θtag, which indicates the inclination angle of the feature recognized based on the output signal of the lidar unit 7, with respect to the detection range of the lidar unit 7. The control device 6 then controls the detection range of the lidar unit 7 based on the reference angle θtag and inclination information that is stored in the memory unit 2 and indicates the angle of the feature with respect to the road surface. This also allows the control device 6 to calibrate the lidar unit 7 when misalignment occurs in the lidar unit 7, thereby maintaining a favorable state in which autonomous driving can continue, just like in the first embodiment.

[0105] <Third Example> The third embodiment differs from the second embodiment in that the feature information contained in the map DB 20 includes information indicating whether calibration can be performed using the target feature as a reference feature (also referred to as "calibration feasibility information Ic"). In the third embodiment, the control device 6 determines the suitability of each feature as a reference feature by referring to the calibration feasibility information Ic.

[0106] Fig. 14 shows the data structure of the map DB 20 stored in the storage unit 2 in the third embodiment. As shown in Fig. 14, the map DB 20 has feature information, which includes calibration feasibility information Ic in addition to the above-mentioned type information, position information, and tilt information. Here, the calibration feasibility information Ic is flag information (adjustment feasibility information) that indicates either permission information that permits the execution of calibration using the corresponding feature as a reference feature, or non-permission information that does not permit the execution of calibration.

[0107] Examples of features for which calibration feasibility information Ic indicating that calibration is permitted to be performed is added to feature information include fixed objects such as buildings whose contours do not vary depending on the external environment, features that are configured approximately perpendicular to the road surface, and features whose contours vary little (i.e., features with contours that are nearly straight). In this way, calibration feasibility information Ic indicating that calibration is permitted to be performed is added to feature information of features that are suitable for calculating the feature reference line Lo (i.e., features that reduce the calculation error of the feature reference line Lo). Examples of features for which calibration feasibility information Ic indicating that calibration is not permitted to be performed is added to feature information include features whose contour shapes are likely to vary depending on the external environment, features that are configured at an angle to the road surface, and features whose contours vary much (i.e., features with contours that are curved or have other complex shapes). In addition, the calibration feasibility information Ic is not limited to being included in the feature information of all features, but may be added only to the feature information of features for which calibration using the reference feature as a reference feature is permitted to be performed, or may be added only to the feature information of features for which calibration using the reference feature as a reference feature is not permitted to be performed.

[0108] The storage unit 2 stores feature information having a data structure as shown in FIG. 14 and supplies it to the control device 6. The control device 6 then executes the flowchart shown in FIG. 13 based on the feature information supplied from the storage unit 2. In this case, in step S302, the control device 6 determines whether each feature is suitable as a reference feature by referring to the calibration feasibility information Ic included in the feature information for each feature. The control device 6 then regards a feature that is determined to be suitable as a reference feature based on the calibration feasibility information Ic as the reference feature, and executes the processes of steps S303 to S306. This enables the control device 6 to accurately select a reference feature, and more accurately determine whether calibration can be performed and perform calibration.

[0109] As described above, the storage unit 2 of the measurement system 100 according to the third embodiment stores feature information having a data structure that includes calibration permission / prohibition information Ic that indicates whether the LIDAR unit 7 arranged on the vehicle is permitted or not permitted to calibrate the detection range of the LIDAR unit 7 based on the feature information. This allows the control device 6 to accurately select a feature to be used as a reference when calibrating the detection range of the LIDAR unit 7.

[0110] <Modification> Next, a description will be given of preferred modifications to Examples 1 to 3. The following modifications may be applied to the above-described examples in any combination.

[0111] (Variation 1) In the first to third embodiments, the signal processing unit SP of the lidar unit 7 may execute part or all of the processing of the control device 6. For example, the signal processing unit SP may execute the processing of the flowchart of FIG. 9 instead of the control device 6. In this case, the signal processing unit SP executes the processing of steps S201 to S204 of FIG. 9 by referring to alignment information IA and the like from the memory unit 2 or a memory built into the lidar unit 7 and acquiring output values ​​of the attitude sensors 8 provided in each scanner housing unit 50, etc. Furthermore, in the calibration processing of step S208, the signal processing unit SP transmits a control signal to the adjustment mechanism 10 and / or the optical transceiver unit TR to adjust the scanning range in accordance with the detected angular deviation. Similarly, the signal processing unit SP may execute the processing of the flowchart of FIG. 13 instead of the control device 6. Note that in this modification, the signal processing unit SP may exchange signals with each component of the measurement system 100, such as the input unit 1, the memory unit 2, and the attitude sensor 8, without going through the control device 6. Furthermore, if the signal processing unit SP executes all of the processing of the control device 6, the measurement system 100 does not need to be provided with the control device 6.

[0112] (Variation 2) In the first to third embodiments, in the example shown in FIG. 4 etc., multiple scanners L are provided for the vehicle, but this is not limiting and only one scanner L may be provided for the vehicle. In this case, the scanner L scans the transmitted light pulses over a 360-degree range, for example, to irradiate the transmitted light pulses to an object present in any direction relative to the vehicle. Even in this case, the control device 6 can detect misalignment of the scanner L provided for the vehicle based on any of the first to third embodiments and perform calibration processing as necessary, thereby enabling the automatic driving to be continued in an optimal manner. In this way, it is sufficient that at least one scanner L is provided for the vehicle.

[0113] (Variation 3) 6, in the first embodiment, the control device 6 detects the angular changes of each scanner L of the lidar unit 7 around the X, Y, and Z axes relative to the vehicle based on the output of the attitude sensor 8. In addition to this, the control device 6 may detect the positional changes of the scanner L along the X, Y, and Z axes relative to the vehicle.

[0114] In this case, for example, each scanner housing unit 50 or scanner L is provided with a sensor (position detection sensor) that detects position changes, and the adjustment mechanism 10 has a function of translating the scanner housing unit 50 or scanner L. In the alignment process shown in FIG. 8, the control device 6 stores information about the placement position and placement angle of each scanner L after alignment adjustment as alignment information IA in the storage unit 2. Then, the control device 6 executes the process of the flowchart in FIG. 9 based on the alignment information IA stored in the storage unit 2. In this case, in step S203, the control device 6 detects the presence or absence of alignment deviations related to the placement position and placement angle of the scanner housing unit 50 or scanner L based on the output of the attitude sensor 8 and the output of the position detection sensor. Thereafter, the control device 6 executes the processes of steps S204 to S210, as in the embodiment, to perform calibration related to alignment deviations of the scanner L, display a predetermined warning, or switch to manual operation. In this way, even if the placement position of the scanner L changes, it is possible to continue measuring the surrounding environment in an appropriate manner by performing calibration, or to switch to manual operation from a safety standpoint.

[0115] (Variation 4) In the first to third embodiments, the measurement system 100 may detect misalignment of an external sensor that emits electromagnetic waves other than the lidar unit 7, instead of detecting misalignment of the lidar unit 7, and may perform calibration processing, etc. on the external sensor. In this case, the measurement system 100 performs calibration processing, etc. on the external sensor to compensate for the misalignment when it is estimated that a misalignment has occurred in the installation position of the external sensor necessary for autonomous driving, based on a processing procedure similar to that of the flowchart in Fig. 9 or 13. This makes it possible to preferably prevent changes in the detection range of the external sensor before and after the occurrence of an accident, and to ensure safety by prompting switching to manual driving when calibration processing cannot be performed.

[0116] (Variation 5) In the first embodiment, the control device 6 may generate or update the alignment information IA at a predetermined timing other than immediately after alignment adjustment. For example, if the control device 6 determines that the road on which the vehicle is traveling is flat, it generates alignment information IA based on the output signal of the attitude sensor 8 provided in each scanner housing section 50 and stores it in the memory unit 2. In this case, the control device 6 may determine whether the road on which the vehicle is traveling is flat based on the output of an acceleration sensor that detects the inclination of the vehicle, or may determine whether the road on which the vehicle is traveling is flat based on current position information and road inclination information of the road data included in the map DB 20.

[0117] (Variation 6) In the first to third embodiments, the measurement system 100 may receive information required for processing from a server device that stores information equivalent to the map DB 20, instead of including the map DB 20.

[0118] FIG. 15 shows a configuration example according to this modification. In the example of FIG. 15, the server device 21 includes a delivery map DB 22 having a data structure similar to that of the map DB 20 shown in FIG. 14, and transmits data such as feature information including calibration feasibility information Ic to the measurement system 100 mounted on each vehicle. In this case, the measurement system 100 may be a communication device such as an on-board device, or may be a system built into the vehicle. Then, in the case of the third embodiment, for example, the measurement system 100 performs calibration according to the flowchart of FIG. 13 based on the feature information and the like received from the server device 21. In this case, the measurement system 100 can accurately determine whether features around the vehicle are suitable as reference features based on the calibration feasibility information Ic, and can determine whether calibration is necessary and perform calibration. [Explanation of symbols]

[0119] 1 Input section 2 Storage section 3 Sensor section 4. Notification Department 5. Communications Department 6. Control device 100 Measurement System

Claims

1. a first acquisition unit that acquires an output signal from a detection device that can detect features present around the moving object; a second acquisition unit that acquires first information regarding an inclination of a feature recognized based on an output signal of the detection device with respect to a detection range of the detection device; a control unit that controls a detection range of the detection device based on the first information and second information related to an angle of the feature with respect to a road surface, the second information being stored in a storage unit; A control device comprising:

2. the detection device is provided on a moving body and is capable of detecting features present around the moving body based on reflected light of emitted light; the first information is information about an inclination of a line based on an outline of a feature recognized based on an output signal of the detection device with respect to a detection range of the detection device set within an emission range of the light, The control unit controls the detection range of the detection device based on the first information and second information related to an angle of a line based on the contour of the feature with respect to a road surface, the second information being stored in a storage unit. The control device according to claim 1 .

3. the first information is information regarding an angle between a boundary line forming one side of a boundary of the detection range and a line based on the contour, The second information is information about an inclination angle of a line based on the contour with respect to a road surface. The control device according to claim 2 .

4. the first information is information regarding an angle between a boundary line forming one side of a boundary of a detection range of the detection device and a line indicating a symmetry axis of the contour, The second information is information about an inclination angle of the line indicating the axis of symmetry with respect to the road surface. The control device according to claim 2 .

5. The control unit controls the detection range of the detection device based on first information on the inclination of a line based on the contour of a feature that is configured perpendicular to a road surface, among features recognized based on the output signal of the detection device, with respect to the detection range, and second information on the angle of the line based on the contour of the feature with respect to the road surface. The control device according to any one of claims 1 to 4.

6. The control unit controls the detection range of the detection device based on first information on the inclination of a line based on the contour of a feature that does not vary depending on the environment, among features recognized based on the output signal of the detection device, with respect to the detection range, and second information on the angle of the line based on the contour of the feature with respect to the road surface. The control device according to any one of claims 1 to 4.

7. A control method executed by a control device, a first acquisition step of acquiring an output signal from a detection device capable of detecting features present around the moving object; a second acquisition step of acquiring first information regarding an inclination of a feature recognized based on an output signal of the detection device relative to a detection range of the detection device; a control step of controlling the detection range of the detection device based on the first information and second information relating to an angle of the feature with respect to a road surface stored in a storage unit; A control method comprising:

8. A computer-executable program, a first acquisition unit that acquires an output signal from a detection device that can detect features present around the moving object; a second acquisition unit that acquires first information regarding an inclination of a feature recognized based on an output signal of the detection device with respect to a detection range of the detection device; A program that causes the computer to function as a control unit that controls the detection range of the detection device based on the first information and second information related to the angle of the feature relative to the road surface, which is stored in a memory unit.

9. A storage medium storing the program according to claim 8.

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