Object position calculation device

Abstract

To obtain relative position information of an external object identified by a plurality of identifiers dispensing with complex computation and without requiring self-position accuracy information.SOLUTION: An object position calculation device is provided with: a first identifier for identifying a solid object; a first position information acquisition unit for acquiring first relative position information; a second identifier for identifying the solid object; a second position information acquisition unit for acquiring second relative position information; a first difference calculation unit for calculating a difference value between the second relative position information and the first relative position information; a second difference calculation unit for calculating a difference value between the difference value of first position information and a correction value of position information; a correction value update unit for updating the correction value of position information on the basis of the difference value of second position information; and an object position calculation unit for correcting the first relative position information on the basis of the updated correction value and calculating the relative position information of the solid object.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This application relates to an object position calculation device.

Background Art

[0002] Conventionally, a technique for estimating the position of a moving object using information from an object position calculation device mounted on the moving object has been known. The moving object is a movable object having a control function such as an automobile or a robot. In addition, an identifier is provided in the object position calculation device provided in the moving object to identify the object. As the identifier, there are devices that measure information on objects outside the moving object such as visible light cameras and radars, devices that measure information on the moving object such as acceleration and angular velocity, and devices that acquire information outside the moving object from data storage such as maps.

[0003] In addition, the position of the moving object can be defined as information representing the absolute or relative position of the moving object. The position of the moving object does not necessarily have to be information representing the absolute position of the moving object on the earth (latitude, longitude, etc.). Information representing the positional relationship between a target existing outside the moving object and the vehicle (for example, the relative distance between the vehicle and the target) is also information indicating the position of the moving object. Here, the target is an object whose position can be identified.

[0004] A technique has been disclosed in which the distance to a target outside the moving object is measured with respect to the predicted self-position of the moving object, and the self-position is corrected using the measured distance information (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] In the technology disclosed in Patent Document 1, the self-position accuracy information of a moving object is acquired, and a gain for obtaining a correction value based on this self-position accuracy information is determined. Then, a correction value for self-position correction is obtained from the difference between two types of measured distances from the moving object to the target object. The self-position accuracy information described in Patent Document 1 is obtained as the variances in the X and Y directions obtained by converting the covariance matrix into the body coordinate system using the Jacobian matrix from the positional relationship between the estimated self-vehicle position of the vehicle and the ground object. Performing complex calculations after obtaining the self-position in this way is a heavy burden on the object position calculation device and can also cause delays in arithmetic processing or an increase in the cost of the processing device.

[0007] The present disclosure addresses such problems. It aims to obtain an object position calculation device that eliminates the need for complex calculations, updates a correction value based on the difference in relative position information of external objects identified by a plurality of discriminators without obtaining self-position accuracy information, and can calculate the position information of an object by appropriate correction.

Means for Solving the Problems

[0008] The object position calculation device according to the present disclosure includes a first discriminator that discriminates a fixed object existing outside the moving object, a first position information acquisition unit that acquires first relative position information between the fixed object discriminated by the first discriminator and the moving object, a second discriminator that discriminates the fixed object, a second position information acquisition unit that acquires second relative position information between the fixed object discriminated by the second discriminator and the moving object, a first difference calculation unit that calculates a difference value between the second relative position information of the fixed object acquired by the second position information acquisition unit and the first relative position information of the fixed object acquired by the first position information acquisition unit and outputs it as a difference value of the first position information, a second difference calculation unit that calculates a difference value between the difference value of the first position information output by the first difference calculation unit and the correction value of the previously updated position information and outputs it as a difference value of the second position information, A correction value update unit that updates a correction value of the position information based on a difference value of the second position information output by the second difference calculation unit, and An object position calculation unit that corrects the first relative position information based on the correction value of the position information updated by the correction value update unit and calculates the relative position information of the fixed object.

Effect of the Invention

[0009] According to the object position calculation device according to the present disclosure, complex calculations are not required, and the correction value is updated based on the difference in the relative position information of external objects identified by a plurality of identifiers without obtaining self-position accuracy information, and an object position calculation device capable of calculating the position information of an object by appropriate correction can be obtained. As a result, it is possible to appropriately correct while suppressing the delay of the arithmetic processing and the cost increase of the processing device, and to calculate the position of an object with high accuracy.

Brief Description of the Drawings

[0010]

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Embodiments for Carrying Out the Invention

[0011] Hereinafter, the embodiments will be described in detail with reference to the drawings. Note that the drawings are schematically shown, and for convenience of explanation, components may be omitted or simplified as appropriate. Also, in the following description, the same reference numerals are given to the same components in the drawings, and their names and functions are also assumed to be the same. Therefore, detailed descriptions thereof may be omitted to avoid duplication.

[0012] 1. Embodiment 1 <Configuration of the Object Position Calculation Device> FIG. 1 is a configuration diagram of an object position calculation device 100 according to Embodiment 1. The object position calculation device 100 mounted on a moving body outputs highly accurate relative position information of a target by appropriately correcting the relative position information to the target acquired by a first position information acquisition unit 15 and the relative position information to the target acquired by a second position information acquisition unit 45.

[0013] A target refers to an object whose position can be identified. Here, the target refers to a fixed object existing outside the moving body and whose position is defined on a map. Hereinafter, the target is referred to as an object. In particular, a target with distinctive features and easy to identify may be referred to as a landmark. A moving body is a general term for controllable moving objects such as automobiles, railway vehicles, airplanes, and robots. Hereinafter, the vehicle may be taken as an example to explain the moving body.

[0014] The object position calculation device 100 has the following functional blocks. A first discriminator 11 and a second discriminator 41 discriminate relative position information of an object existing outside the moving body, and transmit the first relative position information to the first position information acquisition unit 15 and the second relative position information to the second position information acquisition unit 45. The first discriminator 11 and the first position information acquisition unit 15 may be collectively referred to as a first recognition device. The second discriminator 41 and the second position information acquisition unit 45 may be collectively referred to as a second recognition device.

[0015] A difference value between the second relative position information acquired by the second position information acquisition unit 45 and the first relative position information acquired by the first position information acquisition unit 15 is calculated by a first difference calculation unit 21 and transmitted to a second difference calculation unit 22 as a difference value of the first position information. In the second difference calculation unit 22, a correction value and a difference value of the first relative position information are calculated and transmitted to a correction value update unit 23 as a difference value of the second position information.

[0016] In the correction value update unit 23, the correction value is updated based on the difference value of the second position information. The updated correction value is stored in the correction value storage unit 25. In the object position calculation unit 26, the first relative position information acquired by the first position information acquisition unit 15 is corrected using the updated correction value, the relative position of the object is calculated, and it is output as object relative position information. The update necessity determination unit 24 determines whether the correction value can be updated.

[0017] <Identifier> The first identifier 11 and the second identifier 41 identify the relative position of an object existing outside the moving body. The first identifier 11 and the second identifier 41 are constituted by an external monitoring sensor that detects objects around the moving body, or a combination of a positioning device and a map data device.

[0018] As the external monitoring sensor, an image sensor, a radio wave sensor, an optical sensor, an ultrasonic sensor, etc. can be used. The image sensor photographs an object as represented by a surveillance camera, and calculates the distance to the object from the image data photographed within a certain viewing angle range. From the image data, it is also possible to obtain the size, moving direction, moving speed, type, etc. of the object. As the image sensor, a visible light camera, an infrared camera, etc. can be used.

[0019] As the radio wave sensor, a millimeter wave radar (MMWR: Millimeter Wave Radiometer Rader) etc. that uses a frequency band of 24 to 79 GHz can be used. By the radio wave sensor, it is possible to detect the position of an object and detect the moving speed of the object by the Doppler effect.

[0020] As the optical sensor, a laser radar, LiDAR (Light Detection and Ranging), etc. can be used. LiDAR irradiates laser light within a certain viewing field and detects the point cloud data obtained by the reflection of the laser light from the object, and can grasp the position and shape of the object.

[0021] Information processing may be performed for each sensor such as an image sensor, a radio wave sensor, an optical sensor, and an ultrasonic sensor, which are sensors for grasping the external environment. By doing so, it is possible to process the data acquired by various sensors and transmit only the information about the identified object (for example, relative position, etc.) to the first identifier 11 and the second identifier 41.

[0022] The first identifier 11 and the second identifier 41 may use any one of an image sensor, a radio wave sensor, an optical sensor, and an ultrasonic sensor, or may use a combination of information from a plurality of sensors. Further, other sensors may be used for grasping the external environment.

[0023] As a positioning device, the position of the vehicle may be calculated based on the positioning information from a GNSS (Global Navigation Satellite System) that detects the position of the vehicle. As a positioning device, the position of the vehicle may be calculated by a moving distance sensor that detects the rotation speed of the vehicle wheels, a gyro sensor that detects the acceleration, speed, angular acceleration, and angular velocity of the vehicle, etc. As a positioning device, the vehicle position may be specified by receiving information such as tags buried in the road using short-range wireless communication technology such as NFC (Near Field Communication).

[0024] The vehicle position information detected by the positioning device is compared with the position information of the object described in the map data of the map data device, and the relative position information between the vehicle and the object is output. The first identifier 11 and the second identifier 41 may obtain the relative position information from this combination of the positioning device and the map data device.

[0025] <Relative position information> The relative position information with the object may be expressed using X-Y coordinates with the east-west direction as the X-axis and the north-south direction as the Y-axis, or X-Y coordinates with the front-rear direction of the moving body as the Y-axis and the left-right direction as the X-axis. Further, since the earth is a spherical body, coordinates using latitude and longitude may be used for expression. Furthermore, it may be expressed using a vector representing the distance and direction from the moving body to the object. The comparison and correction of the relative position information will be described with reference to FIG. 2.

[0026] FIG. 2 is a diagram showing an example of the relative position between a moving body and an object according to Embodiment 1. In FIG. 2, the moving body is the vehicle 50, and the case where the relative position of the object is represented in the X-Y coordinates with the left-right direction with the vehicle 50 as the origin being the X-axis and the front-rear direction being the Y-axis is illustrated.

[0027] <Calculation of each vector> The first relative position information acquired by the first position information acquisition unit is indicated by a △ mark as P1(X1, Y1). In other words, the relative position of the object from the vehicle is indicated by the vector P1 (solid line arrow). The second relative position information of the object acquired by the second position information acquisition unit is indicated by an ◎ mark as P2(X2, Y2). In other words, the relative position of the object from the vehicle is indicated by the vector P2 (solid line arrow).

[0028] The difference value of the first position information calculated by the first difference calculation unit 21 is indicated by a vector D1 (dashed-dotted line). The vector D1 is the difference obtained by subtracting the first relative position information P1(X1, Y1) from the second relative position information P2(X2, Y2), and is the result of subtracting the vector P1 from the vector P2. In FIG. 2, the X component of the vector D1 is calculated as X2 - X1, and the Y component is calculated as Y2 - Y1.

[0029] The difference value of the second position information calculated by the second difference calculation unit 22 is indicated by a vector D2 (dashed-dotted line) extending from the □ mark to the ◎ mark. The vector D2 is the difference obtained by subtracting the vector CL, which is the latest value of the correction value, from the vector D1, which is the difference value of the first position information. The vector CL is indicated by a vector (broken line) from the △ mark to the □ mark in FIG. 2. If the vector D2, which is the second relative position information, is directly added to the vector CL, which is the latest correction value before update, to obtain a new correction value, a correction value for calculating the second relative position information P2 based on the first relative position information P1 can be obtained.

[0030] Here, when updating the pre-update correction value (vector CL), it is updated using the gain K. Specifically, the correction value update unit 23 calculates the post-update correction value (vector CN) based on the difference value of the second position information (vector D2) and the pre-update correction value (vector CL). The post-update correction value is calculated, for example, by the following formula.

[0031] (Post-update correction value CN) = (Pre-update correction value CL) + K × (Difference value of the second position information D2) ···(1) Here, K is the gain and is a parameter for adjusting the responsiveness to the time variation of the correction value. K is a value between 0 and 1. K may be a fixed value or may be a variable value based on an existing algorithm such as a Kalman filter.

[0032] Now, when K = 0.4, K × (Difference value of the second position information) is calculated as (K × vector D2) in FIG. 2 and is represented as a vector extending from the □ mark to the 〇 mark. And in FIG. 2, the updated correction value is represented by vector CN and is represented as a vector extending from the △ mark to the 〇 mark.

[0033] The X component and Y component of each vector can be defined as follows. · First relative position information: Vector P1(X1, Y1) · Second relative position information: Vector P2(X2, Y2) · Difference value of the first position information: Vector D1(XD1, YD1) · Difference value of the second position information: Vector D2(XD2, YD2) · Pre-update correction value: Vector CL(XL, YL) · Post-update correction value: Vector CN(XN, YN) · Relative position information of the object calculated using the post-update correction value: Vector PO(XO, YO)

[0034] The relationship of each vector is as follows. · Vector D1 = Vector P2 - Vector P1 · Vector D2 = Vector D1 - Vector CL · Vector CN = Vector CL + K × Vector D2 · Vector PO = Vector P1 + Vector CN

[0035] <Regarding the X coordinate> XD1 = X2 - X1 XD2 = XD1 - XL = X2 - X1 - XL XN = XL + K × XD2 = XL + K × (X2 - X1 - XL) XO = X1 + XN = X1 + XL + K × (X2 - X1 - XL) <Regarding the Y coordinate> YD1 = Y2 - Y1 YD2 = YD1 - YL = Y2 - Y1 - YL YN = YL + K × YD2 = YL + K × (Y2 - Y1 - YL) YO = Y1 + YN = Y1 + YL + K × (Y2 - Y1 - YL)

[0036] With such a procedure, complex calculations are not required, and without obtaining self-position accuracy information, the correction value can be updated based on the difference in the relative position information of external objects identified by two types of discriminators. Then, an object position calculation device capable of calculating the position information of an object by appropriate correction can be obtained. As a result, it is possible to appropriately perform correction while suppressing delays in arithmetic processing and cost increases of processing devices, and to calculate the position of an object with high accuracy.

[0037] In the example of FIG. 2, the first relative position information P1 regarding the object acquired by the first position information acquisition unit 15 is a value different from the second relative position information P2 regarding the same object acquired by the second position information acquisition unit 45. This is due to the difference in the accuracy of the first discriminator 11 and the second discriminator 41.

[0038] For example, it may be possible to use a sensor that can identify up to a long distance as the first discriminator 11. And, as the second discriminator 41, it may be possible to use a sensor with a short discriminable distance but high accuracy in object discrimination at a short distance.

[0039] The object position calculation device 100 outputs relative position information calculated by correcting the first relative position information of the object obtained from the first identifier 11 with respect to the second relative position information to the same object obtained from the second identifier 41. By using this corrected relative position information, it becomes possible to utilize both the advantage of the first identifier 11 that can identify objects at a far position and the advantage of the second identifier 41 that has high relative position identification accuracy at a near position.

[0040] When the object to be identified is a building or a sign serving as a landmark, a millimeter-wave radar may be used as the first identifier 11, and a LiDAR or an image sensor may be used as the second identifier 41. The millimeter-wave radar can detect objects at a relatively long distance and can perform certain identification even in an environment where fog, haze, or rain occurs. In contrast, LiDAR and image sensors can perform highly accurate identification at a short distance, but the identifiable distance is shortened in an environment where fog, haze, or rain occurs.

[0041] Note that the difference in characteristics between the first identifier 11 and the second identifier 41 does not necessarily have to be the same as the above example. For example, the first identifier 11 may have high measurement accuracy of the relative distance, while the second identifier 41 may have high measurement accuracy of the relative angle. Even in this case, a millimeter-wave radar may be used as the first identifier 11, and a LiDAR or an image sensor may be used as the second identifier 41. This is because the millimeter-wave radar can accurately identify the distance to the object, but the identification accuracy of the relative angle is not high. In contrast, LiDAR or an image sensor has high identification accuracy of the relative angle.

[0042] <Hardware Configuration of Object Position Calculation Device> FIG. 3 is a hardware configuration diagram of the object position calculation device. In the present embodiment, the object position calculation device 100 is an electronic control device mounted on a moving body for calculating relative position information of an object existing outside the moving body. Each function of the object position calculation device 100 is realized by a processing circuit provided in the object position calculation device 100. Specifically, the object position calculation device 100 includes, as a processing circuit, an arithmetic processing device 90 (computer) such as a CPU (Central Processing Unit), a storage device 91 that exchanges data with the arithmetic processing device 90, an input circuit 92 that inputs an external signal to the arithmetic processing device 90, and an output circuit 93 that outputs a signal from the arithmetic processing device 90 to the outside. Each hardware such as the arithmetic processing device 90, the storage device 91, the input circuit 92, and the output circuit 93 is connected to each other by a wired network such as a bus or a wireless network.

[0043] As the arithmetic processing unit 90, an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), a DSP (Digital Signal Processor), a GPU (Graphics Processing Unit), an FPGA (Field Programmable Gate Array), various logic circuits, various signal processing circuits, etc. may be provided. Further, as the arithmetic processing unit 90, a plurality of the same type or different types may be provided, and each process may be executed in a shared manner. As the storage device 91, a RAM (Random Access Memory) configured to be able to read and write data from the arithmetic processing unit 90, a ROM (Read only Memory) configured to be able to read data from the arithmetic processing unit 90, etc. are provided. As the storage device 91, a non-volatile or volatile semiconductor memory such as a flash memory, an SSD (Solid State Drive), an EPROM, an EEPROM, a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD, etc. may be used. The input circuit 92 is connected with various sensors, switches, and communication lines, and includes an A / D converter, a communication circuit, etc. that input the output signals of these sensors and switches and communication information to the arithmetic processing unit 90. The output circuit 93 includes a drive circuit, a communication circuit, etc. that output a control signal from the arithmetic processing unit 90. The interfaces of the input circuit 92 and the output circuit 93 may be based on specifications such as CAN (Control Area Network) (registered trademark), Ethernet (registered trademark), USB (Universal Serial Bus) (registered trademark), DVI (Digital Visual Interface) (registered trademark), HDMI (High-Definition Multimedia Interface) (registered trademark). Further, separately from the input circuit 92 and the output circuit 93, communication may be performed by directly connecting from the arithmetic processing unit 90 to a communication device.

[0044] Each function of the object position calculation device 100 is realized by the arithmetic processing unit 90 executing software (program) stored in a storage device 91 such as a ROM and cooperating with other hardware of the object position calculation device 100 such as the storage device 91, the input circuit 92, and the output circuit 93. Note that setting data such as threshold values and determination values used by the object position calculation device 100 are stored in the storage device 91 such as a ROM as part of the software (program). Each function of the object position calculation device 100 may be configured by software modules, or may be configured by a combination of software and hardware.

[0045] <Processing of the object position calculation device> FIG. 4 is a first flowchart showing the processing of the object position calculation device 100 according to the first embodiment. FIG. 5 is a second flowchart showing the processing of the object position calculation device 100. FIG. 5 shows the continuation of the processing in FIG. 4.

[0046] The processing shown in FIGS. 4 and 5 is executed by the arithmetic processing unit of the object position calculation device 100. This processing may be executed at regular intervals (for example, every 1 ms). Instead of at regular intervals, it may be executed by events such as the first discriminator 11 and the second discriminator 41 of the object position calculation device 100 identifying an object.

[0047] Consider the case where the identification cycles of the first identifier 11 and the second identifier 41 for identifying an external object are different from the cycle in which the object position calculation device 100 periodically updates the correction value. The relative position information to the object used by the object position calculation device 100 shall be the relative position information to the object in the most recent identification cycle. Here, the most recent identification cycle can be defined as the past identification cycle closest to the current time. Note that the relative position information used by the object position calculation device 100 does not necessarily have to be the relative position information to the object in the most recent identification cycle. The relative position information from the moving object to the object in the identification cycles from the present to the past, or their average value, etc. may be used. Regarding the relative position information of the external object identified by the first identifier 11 and the second identifier 41, it is also possible that the first position information acquisition unit 15 and the second position information acquisition unit 45 acquire the information obtained by performing appropriate filtering processing to remove noise.

[0048] Start the process of FIG. 4. In step S101, the first position information acquisition unit 15 acquires the first relative position information P1 of the object identified by the first identifier 11. If the identification of the first relative position information P1 of the object by the first position information acquisition unit 15 fails, for example, if there is no object that can be measured by the first identifier 11, or if the measuring device of the first identifier 11 has stopped functioning, etc., it is determined that it is an invalid value as the first relative position information P1 and stored.

[0049] In step S102, the second position information acquisition unit 45 acquires the second relative position information P2 of the object identified by the second identifier 41. If the identification of the second relative position information P2 of the object by the second position information acquisition unit 45 fails, for example, if there is no object that can be measured by the second identifier 41, or if the measuring device of the second identifier 41 has stopped functioning, etc., it is determined that it is an invalid value as the second relative position information P2 and stored.

[0050] In step S103, the first difference calculation unit 21 calculates, as the difference value D1 of the first position information, the value obtained by subtracting the first relative position information P1 from the second relative position information P2. The difference value may be obtained by taking the difference between the respective position information in terms of the X-axis coordinate component and the Y-axis coordinate component. If either the first relative position information P1 or the second relative position information P2 is an invalid value, it is determined that the difference value D1 of the first position information is an invalid value and stored.

[0051] In step S104, the latest correction value stored in the correction value storage unit 25 is read out as the pre-update correction value CL. If the pre-update correction value CL is not stored in the correction value storage unit 25 when this step S104 is executed, the initial value of the correction value is set as the pre-update correction value CL. This initial value may be a predetermined fixed value, or may be set as a value that changes according to the surrounding environment or the like.

[0052] In step S105, the second difference calculation unit 22 calculates, as the difference value D2 of the second position information, the value obtained by subtracting the pre-update correction value CL from the difference value D1 of the first position information. However, if the difference value D1 of the first position information is an invalid value, it is determined that the difference value D2 of the second position information is also an invalid value and stored.

[0053] In step S106, it is confirmed that both the difference value D1 of the first position information and the difference value D2 of the second position information are valid. Then, in step S107, it is determined whether both difference values are valid. If both are valid (the determination is YES), the process proceeds to step S112. If either of the difference values is not valid (the determination is NO), the process proceeds to step S115.

[0054] In step S112, the correction value is updated. Specifically, the correction value update unit 23 calculates the post-update correction value CN based on the difference value D2 of the second position information and the pre-update correction value CL. The post-update correction value CN is calculated by Equation (1).

[0055] For the update of the correction value in step S112, methods other than the above may be used. In step S113, the correction value update unit 23 stores the calculated updated correction value CN in the correction value storage unit 25.

[0056] In step S115, the object position calculation unit 26 adds the updated correction value CN to the first relative position information P1 obtained. The added value is calculated as the corrected relative position information PO. Then the process ends.

[0057] In the above description, the difference value D1 of the first position information is set as (second relative position information P2) - (first relative position information P1) in step S103 (that is, the value obtained by subtracting the first relative position information P1 from the second relative position information P2 is used). Instead of this, in step S103, the difference value D1 of the first position information may be set as (first relative position information P1) - (second relative position information P2). However, in that case, it is necessary to calculate (first position information difference value D1) + (pre-update correction value CL) as the second position information difference value D2 in step S105.

[0058] Also, separately from the above, the update of the correction value in step S112 can also be performed based on the following formula.

[0059] (Updated correction value CN) = K × (Difference value D1 of the first position information) + (1 - K) × (Pre-update correction value CL) ···(2) Here, K is a parameter for adjusting the responsiveness to the time variation of the correction value, and is a value between 0 and 1. For the update of the correction value in step S112, methods other than the above may be used.

[0060] According to the object position calculation device 100 according to Embodiment 1, after storing the updated correction value CN calculated by the correction value update unit 23 in the correction value storage unit 25, the object position calculation unit 26 uses the stored correction value to correct the relative position information to the object. Further, when the difference value D1 of the first position information or the difference value D2 of the second position information is an invalid value, the correction value stored in the correction value storage unit 25 is sent to the object position calculation unit 26 without being changed. With this configuration, even when the first position information acquisition unit 15 or the second position information acquisition unit 45 fails to acquire the relative distance to the object, the relative position information is corrected using the correction value calculated in the past cycle, and the relative position information is calculated.

[0061] For example, regarding the situation of FIG. 2 described above, the second discriminator 41 is a visible light camera. With the configuration of Embodiment 1, even when the measurement of the partition line by the camera fails due to a temporary change in the light amount, error correction of the relative distance to the partition line with respect to the first discriminator 11 is possible. That is, even when the discriminator temporarily cannot effectively identify the object, the frequency of a situation where the estimation accuracy of the relative position information to the object and the vehicle position decreases can be reduced.

[0062] 2. Embodiment 2 <Configuration of the object position calculation device> FIG. 6 is a configuration diagram of the object position calculation device 100 according to Embodiment 2. The part where the second discriminator accuracy information acquisition unit 32 and the map database 33 are added is different from the configuration diagram of FIG. 1 according to Embodiment 1. The hardware configuration diagram of FIG. 3 is also applicable to Embodiment 2.

[0063] In Embodiment 1, when the relative position information to the object output from the first position information acquisition unit 15 and the second position information acquisition unit 45 is valid, the correction value is updated, and the relative position information is corrected using the updated correction value. When the relative position information to the object is not valid, the relative position information is corrected without updating the correction value.

[0064] However, even when the actual position information acquisition unit can acquire valid relative position information, the reliability of the relative position information may be low. In this case, in the first embodiment, the correction value is updated based on the relative position information with low reliability, and the updated correction value is sent to the object position calculation unit 26. Then, the accuracy of the relative position information to the object corrected using the updated correction value may deteriorate.

[0065] <Discriminator accuracy information> Therefore, in the object position calculation device 100 according to the second embodiment, a second discriminator accuracy information acquisition unit 32 for acquiring the discriminator accuracy information of the second discriminator 41 is provided. According to the second discriminator accuracy acquired by the second discriminator accuracy information acquisition unit 32, the update gain updated by the correction value update unit 23 can be changed, and the necessity of update can be determined by the update necessity determination unit 24. With this configuration, when the accuracy of the second relative position information acquired by the second position information acquisition unit 45 is low, the frequency of deterioration of the accuracy of the relative position information to the corrected object can be reduced.

[0066] Here, the discriminator accuracy information of the second discriminator 41 is defined as information regarding the measurement accuracy of the relative position information acquired from the second discriminator 41. For example, when the second relative position information of the object is discriminated by the second discriminator 41, the discriminator accuracy information of the second discriminator 41 is, for example, the standard deviation regarding the measurement error of the relative distance. Further, the discriminator accuracy information of the second discriminator 41 may be information representing the conditions under which the measurement error of the second position information acquisition unit 45 increases or decreases. For example, when the second position information acquisition unit 45 is a visible light camera of an image sensor, information regarding whether the visible light camera is photographing an area with a large amount of light or an area with a small amount of light, information regarding dirt attached to the photographing lens of the visible light camera, information representing the magnitude of vibration with respect to the visible light camera, etc. may also be the discriminator accuracy information of the second discriminator 41.

[0067] Furthermore, the identification accuracy information of the second identifier 41 may be set for each road section. The identification accuracy information for each road section may be described in the map data stored in the map database 33. In this case, the second identifier accuracy information acquisition unit 32 can acquire the identification accuracy information of the second identifier 41 by exchanging information with the map database 33.

[0068] When the second identifier 41 is a visible light camera of an image sensor, the identification accuracy decreases in road sections including inside the tunnel and the tunnel exit. A decrease in the ambient light amount inside the tunnel and a sudden change in the light amount in the exit area of the tunnel cause errors in recognizing the captured image of the visible light camera, leading to a decrease in accuracy. By the second identifier accuracy information acquisition unit 32 acquiring the expected degree of accuracy decrease, the gain of updating the correction value in this road section may be changed to slow down the update speed. A step may be provided for the degree of accuracy decrease, and the gain of updating the correction value in the road section may be changed. Also, in road sections including inside the tunnel and the tunnel exit, it may be possible to prohibit the update of the correction value.

[0069] In this way, road sections where the identification accuracy decreases may be registered in the data of the map database 33. As road sections where the identification accuracy decreases, for example, roads passing through dark forests with poor visibility, road sections where fog, haze, or rain is occurring, and road sections with insufficient night lighting facilities during night hours, the degree of decrease in identification accuracy may be registered.

[0070] <Processing of the object position calculation device> FIG. 7 is a second flowchart showing the processing of the object position calculation device 100 according to Embodiment 2. The first flowchart showing the processing of the object position calculation device 100 according to Embodiment 2 is the same as FIG. 4. FIG. 7 shows the continuation of the processing in FIG. 4.

[0071] The flowchart in FIG. 7 is different in that steps S108 to S111 are added between steps S107 and S112 of the flowchart in FIG. 5. The main differences will be described.

[0072] The processes shown in FIGS. 4 and 7 are executed by the arithmetic processing unit of the object position calculation device 100. This process may be executed at regular intervals (for example, every 1 ms). Instead of at regular intervals, it may also be executed by events such as the first discriminator 11 and the second discriminator 41 of the object position calculation device 100 identifying an object.

[0073] After the process of FIG. 4, at step S107 in FIG. 7, it is determined whether both difference values are valid. If both are valid (the determination is YES), the process proceeds to step S108. If either of the difference values is not valid (the determination is NO), the process proceeds to step S115.

[0074] At step S108, the second discriminator accuracy information acquisition unit 32 acquires the discrimination accuracy information of the second discriminator 41. At step S109, it is determined whether the accuracy of the acquired discrimination accuracy information is greater than a predetermined discrimination accuracy determination value. If the accuracy is greater than the discrimination accuracy determination value (the determination is YES), the process proceeds to step S110. If the accuracy is less than or equal to the discrimination accuracy determination value (the determination is NO), the process proceeds to step S111.

[0075] At step S110, a gain K (gain K) for updating the correction value is set. Since the accuracy is greater than the discrimination accuracy determination value, a high gain value KH (for example, 0.6) is set as the gain K. Then the process proceeds to step S112.

[0076] At step S111, a gain K (gain K) for updating the correction value is set. Since the accuracy is less than or equal to the discrimination accuracy determination value, a low gain value KL (for example, 0.2) is set as the gain K. Then the process proceeds to step S112. Here, if the gain K is set to 0, no correction is performed and the pre-update correction value is used as it is.

[0077] At step S112, the correction value is updated. Using the gain K for updating the correction value, the correction value update unit 23 calculates an updated correction value CN based on the difference value D2 of the second position information and the pre-update correction value CL. The updated correction value CN is calculated by Equation (1).

[0078] According to the object position calculation device 100 according to the second embodiment configured as described above, the second discriminator accuracy information acquisition unit 32 can update the correction value according to the discrimination accuracy of the second discriminator 41 by acquiring the discrimination accuracy information of the second discriminator 41. Thus, when the relative position information output from the second position information acquisition unit 45 is a valid value but its accuracy is low, the gain K corresponding to the accuracy is set and the correction value is updated.

[0079] Therefore, the update speed of the correction value is adjusted according to the change in the accuracy of the second discriminator 41. That is, the degree of reflection of the second relative position information identified by the second discriminator 41 is adjusted. Therefore, deterioration of the accuracy of the corrected relative position information can be limited.

[0080] Also, by acquiring the discrimination accuracy information defined for each road section, it is possible to appropriately acquire the discrimination accuracy information of the second discriminator 41 without performing complicated and large-scale calculations to obtain the self-position accuracy information. Therefore, it is possible to appropriately perform correction while suppressing delay in arithmetic processing and increase in cost of the processing device, and calculate the position of an object with high accuracy.

[0081] 3. Third Embodiment <Configuration of Object Position Calculation Device> FIG. 8 is a configuration diagram of the object position calculation device 100 according to the third embodiment. The part where the correction value prediction unit 34 is added is different in FIG. 8 from the configuration diagram of FIG. 1 according to the first embodiment. The hardware configuration diagram of FIG. 3 is also applicable to the third embodiment.

[0082] A reasonable correction value used in the object position calculation device 100 may vary with the passage of time. For example, consider a case where the first discriminator 11 identifies the relative position information from the vehicle to the object by a combination of a positioning device performing inertial navigation using a gyro sensor and a map data device. Generally, the error of inertial navigation accumulates and increases according to the passage of time or the moving distance. In such a case, the difference from the second relative position information by the second discriminator 41 that identifies the relative position information by another method tends to increase.

[0083] If, for some reason, the relative position information from the second identifier 41 cannot be obtained, in the object position calculation device 100 according to the first embodiment, the previous correction value is used to correct the first relative position information and output it as the object relative position information. If the state where the relative position information from the second identifier 41 cannot be obtained continues, the same previous correction value before update will continue to be used.

[0084] <Correction value prediction unit> As time passes, if the correction value changes, continuously using the same previous correction value before update is not appropriate. This is because by continuously using the same correction value, the error in the relative position information to the corrected object changes. This error increases as the time when the relative position information from the second identifier 41 cannot be obtained continues.

[0085] In the object position calculation device 100 according to the third embodiment, the correction value prediction unit 34 predicts a future correction value. The correction value prediction unit 34 predicts a future correction value based on the history of updates of the past correction values stored in the correction value storage unit 25. The correction value prediction unit 34 calculates a reasonable correction value at the current time and stores it in the correction value storage unit 25. With such a configuration, it is possible to predict a reasonable correction value and use the predicted correction value to reduce the frequency of deterioration in the accuracy of the corrected relative position information.

[0086] <Processing of the object position calculation device> FIG. 9 is a first flowchart showing the processing of the object position calculation device 100 according to the third embodiment. FIG. 10 is a second flowchart showing the processing of the object position calculation device 100 according to the third embodiment. FIG. 10 shows the continuation of the processing in FIG. 9.

[0087] The flowchart of FIG. 9 is different in that steps S121 to S123 are added before step S101 of the flowchart of FIG. 4. The flowchart of FIG. 10 is different in that steps S124 and S114 are added between steps S107 and S115 of the flowchart of FIG. 5, and after step S113, the process proceeds to step S114. The main differences will be described below.

[0088] The processes shown in FIGS. 9 and 10 are executed by the arithmetic processing unit of the object position calculation device 100. This process may be executed at predetermined intervals (for example, every 1 ms). Instead of at predetermined intervals, it may be executed by events such as the first identifier 11 and the second identifier 41 of the object position calculation device 100 identifying an object.

[0089] Starting the process of FIG. 9, at step S121, the correction value prediction unit 34 acquires the past correction value stored in the correction value storage unit 25. This is to check the history of updated correction values.

[0090] At step S122, from the history of updated correction values, the correction value prediction unit 34 predicts a future correction update value and sets it as a predicted correction value. Here, the predicted correction value is defined as the correction value at the current time calculated based on a model (prediction model) in which the past correction value stored in the correction value storage unit 25 fluctuates. As an example of the prediction model, for example, a model in which the correction value fluctuates linearly with respect to the elapsed time T may be adopted. In that case, the predicted correction value CF may be calculated by the following formula.

[0091] (Predicted correction value CF)=(Correction value before update CL)+(Elapsed time T)×(Coefficient KC) ···(3) Here, the elapsed time T is defined as the elapsed time from the past time (past cycle) when the latest correction value before update CL was stored to the current time (current cycle). Also, the coefficient KC may be a predetermined fixed value, or a variable value set according to the elapsed time by an existing algorithm such as a Kalman filter.

[0092] In addition, when the past correction value obtained in step S121 is an invalid value, the initial value of the correction value is set to the past correction value. This initial value may be a predetermined fixed value or a variable value set according to the surrounding environment or the like.

[0093] Then, in step S123, the correction value prediction unit 34 stores the predicted correction value CF in the correction value storage unit 25. Note that when no correction value is stored in the correction value storage unit 25 at the time when step S121 is executed, the predicted correction value CF is stored as an invalid value. Then, the process proceeds to step S101, and the same processing as in FIG. 4 is executed.

[0094] In step S107 of FIG. 10, it is determined whether both difference values are valid. If both are valid (the determination is YES), the process proceeds to step S112. If either of the difference values is not valid (the determination is NO), the process proceeds to step S124.

[0095] In step S124, in order to use the predicted correction value CF calculated in step S122 as the updated correction value CN used in the correction operation, it is stored in the correction value storage unit 25. Then, the process proceeds to step S114.

[0096] In step S112, the correction value is updated. Specifically, the correction value update unit 23 calculates the updated correction value CN based on the difference value D2 of the second position information and the correction value CL before update. The updated correction value CN is calculated by Equation (1). In step S113, the correction value update unit 23 stores the calculated updated correction value CN in the correction value storage unit 25. Then, the process proceeds to step S114.

[0097] In step S114, the updated correction value CN is read from the correction value storage unit 25. This is for use in calculating the corrected relative position information PO.

[0098] Then, in step S115, the updated correction value CN is added to the first relative position information P1 acquired by the object position calculation unit 26. The added value is calculated as the corrected relative position information PO. Then, the process ends.

[0099] According to the object position calculation device 100 according to Embodiment 3, the correction value prediction unit 34 calculates a predicted correction value CF from the update history of the past correction values stored in the correction value storage unit 25. When the difference value D1 of the first position information or the difference value D2 of the second position information is not valid, instead of using the pre-update correction value, the predicted correction value CF is used as the post-update correction value CN.

[0100] The object position calculation unit 26 uses the predicted correction value CF as the post-update correction value CN and corrects the first relative distance. With such a configuration, even when a proper correction value varies with time and the difference value of the second position information becomes an invalid value, the correction is appropriately performed. Since the correction is performed by the predicted correction value CF calculated by the correction value prediction unit 34, the frequency of deterioration in the accuracy of the post-correction relative position information can be reduced.

[0101] 4. Embodiment 4 <Configuration of Object Position Calculation Device> FIG. 11 is a configuration diagram of an object position calculation device 100 according to Embodiment 4. The part where the first discriminator accuracy information acquisition unit 31 is added is different in FIG. 11 from the configuration diagram of FIG. 8 according to Embodiment 3. The hardware configuration diagram of FIG. 3 is also applicable to Embodiment 4.

[0102] In the object position calculation device 100 according to Embodiment 3, the correction value prediction unit 34 predicts a future correction value based on a prediction model from the update history of the past correction values in the correction value storage unit 25. However, a specific prediction model is not always valid.

[0103] For example, consider a case where the first discriminator 11 is a device that measures the case where the relative position information from the vehicle to the object is identified by a combination of a positioning device performing inertial navigation using a gyro sensor and a map data device. The rate at which the error of inertial navigation increases over time is different during the period when the vehicle is moving straight and the period when the vehicle is meandering.

[0104] In such a situation, when the correction value prediction unit 34 adopts a prediction model on the premise of the period during which the vehicle is moving straight, the frequency at which the predicted value of the correction value becomes an inappropriate value increases during the period when the vehicle is meandering. As a result, the frequency of deterioration in the accuracy of the corrected relative position information increases.

[0105] <Discriminator accuracy acquisition unit> Therefore, in the object position calculation device 100 according to the fourth embodiment, a first discriminator accuracy information acquisition unit 31 for acquiring the discrimination accuracy information of the first discriminator 11 is added. The correction value prediction unit 34 is configured to calculate a predicted correction value CF based on the discrimination accuracy information of the first discriminator 11. With this configuration, even when a proper correction value varies with time due to an error in the first position information acquisition unit 15, the reliability of the predicted correction value CF can be improved. The frequency at which the predicted correction value CF deviates significantly from an appropriate value can be reduced, and as a result, the frequency of deterioration in the accuracy of the corrected relative position information can be decreased.

[0106] Here, the discrimination accuracy information of the first discriminator 11 is defined as information regarding the measurement accuracy of the relative position information that the first discriminator 11 discriminates and the first position information acquisition unit 15 acquires. The discrimination accuracy information of the first discriminator 11 may be, for example, the standard deviation of the measurement error of this relative position information.

[0107] Further, the discrimination accuracy information of the first discriminator 11 may be information representing conditions under which the measurement error of the first discriminator 11 increases or decreases. For example, when the first discriminator 11 is a device that measures the relative distance from the vehicle to an object using GNSS and a map data device, information regarding the communication quality with artificial satellites or the like may be used as the discrimination accuracy information of the first discriminator 11. Furthermore, when the first discriminator 11 is configured by a combination of a positioning device using a gyro sensor and a map data device and measures the relative position information from the vehicle to an object, information regarding whether the vehicle is traveling in a manner in which the error of the gyro sensor is likely to increase may be used as the discrimination accuracy information of the first discriminator 11.

[0108] <Processing of object position calculation device> FIG. 12 is a first flowchart showing the processing of the object position calculation device 100 according to Embodiment 4. The second flowchart showing the processing of the object position calculation device 100 according to Embodiment 4 is the same as FIG. 10. FIG. 10 shows the continuation of the processing of FIG. 12.

[0109] The flowchart of FIG. 12 is different in that steps S131 to S134 are provided instead of step S122 in the flowchart of FIG. 9. The main differences will be described.

[0110] The processing shown in FIGS. 12 and 10 is executed by the arithmetic processing unit of the object position calculation device 100. This processing may be executed at predetermined intervals (for example, every 1 ms). Instead of at predetermined intervals, it may be executed by events such as the first discriminator 11 and the second discriminator 41 of the object position calculation device 100 identifying an object.

[0111] Starting the processing of FIG. 12, at step S121, the correction value prediction unit 34 acquires the past correction value stored in the correction value storage unit 25. This is to check the history of updated correction values.

[0112] At step S131, the first discriminator accuracy information acquisition unit 31 acquires the discrimination accuracy information of the first discriminator 11. The discrimination accuracy information depends on the type of discriminator.

[0113] For example, when the first discriminator 11 is a device that measures the relative distance from a vehicle to an object using GNSS and a map data device, it can be determined to be of low accuracy in a situation where it is shielded by a tunnel or the like and the communication signal quality with artificial satellites or the like is low. Also, for example, when the first discriminator 11 is a device configured by a combination of a positioning device using a gyro sensor and a map data device, it can also be determined to be of low accuracy if the turning angle of the vehicle is greater than a predetermined threshold value.

[0114] In step S132, it is determined whether the accuracy of the acquired identification accuracy information is greater than a predetermined identification accuracy determination value. If the accuracy is greater than the identification accuracy determination value (the determination is YES), the process proceeds to step S133. If the accuracy is less than or equal to the identification accuracy determination value (the determination is NO), the process proceeds to step S134.

[0115] In step S133, the correction value prediction unit 34 calculates a predicted correction value CF based on a prediction model with relatively small fluctuations in the correction value and the past correction values. Here, the prediction model with relatively small fluctuations in the correction value is defined as a model that assumes that the fluctuations in the correction value per unit time are smaller than those of the correction value prediction model used in step S134.

[0116] For example, the case where the coefficient KC in the formula (3) used in the description of step S122 in Embodiment 3 is set to a small value corresponds to this model. Also, for example, when predicting the correction value by a Kalman filter, the case where the parameter representing the magnitude of the prediction error is set to a small value corresponds to this model. After calculating the predicted correction value CF, the process proceeds to step S123.

[0117] In step S134, the correction value prediction unit 34 calculates a predicted correction value CF based on a prediction model with relatively large fluctuations in the correction value and the past correction values. Here, the prediction model with relatively large fluctuations in the correction value is defined as a model that assumes that the fluctuations in the correction value per unit time are larger than those of the correction value prediction model used in step S133.

[0118] For example, the case where the coefficient KC in the formula (3) used in the description of step S122 in Embodiment 3 is set to a large value corresponds to this model. Also, for example, when predicting the correction value by a Kalman filter, the case where the parameter representing the magnitude of the prediction error is set to a large value corresponds to this model. After calculating the predicted correction value CF, the process proceeds to step S123.

[0119] In step S123, the correction value prediction unit 34 stores the predicted correction value CF in the correction value storage unit 25. Thereafter, the same processing as step S101 in FIG. 9 is performed.

[0120] According to the object position calculation device 100 according to the fourth embodiment, the correction value prediction unit 34 is configured to calculate a predicted and corrected value using different prediction models according to the discrimination accuracy information of the first discriminator 11. With this configuration, the frequency with which the predicted and corrected value deviates greatly from a proper value with respect to the temporal variation of a proper correction value caused by the error of the first position information acquisition unit 15 can be reduced, and as a result, the frequency with which the accuracy of the corrected relative distance deteriorates can be decreased.

[0121] 5. Fifth Embodiment <Configuration of Object Position Calculation Device> FIG. 13 is a configuration diagram of an object position calculation device 100 according to the fifth embodiment. The difference from the configuration diagram of FIG. 1 according to the first embodiment is that in FIG. 13, it is clearly shown that the first discriminator 11 is composed of an inertial sensor / speedometer 12, a satellite positioning device 13, and a map database 14. The inertial sensor / speedometer 12 corresponds to a gyro sensor. The satellite positioning device 13 is a device that performs positioning based on positioning information from GNSS. The map database 14 corresponds to a map data device. The hardware configuration diagram of FIG. 3 is also applicable to the fourth embodiment.

[0122] In the fifth embodiment, based on the information of the inertial sensor / speedometer 12, the satellite positioning device 13, and the map database 14, the first position information acquisition unit 15 acquires first relative position information. Thereby, the problems in the case where an external monitoring sensor such as a visible light camera is used as the first discriminator 11 can be solved. For example, the frequency of failure to acquire relative position information due to measurement environments such as a decrease in the amount of light around the object and a shielding object that blocks the view of the object can be reduced.

[0123] The inertial sensor and speedometer 12 acquires data of the inertial sensor and speedometer in the current cycle. The satellite positioning device 13 acquires satellite positioning information in the current cycle. The map database 14 shares map data within the first identifier 11. As a whole, the first identifier 11 collates the vehicle position information detected by the positioning device with the position information of the objects described in the map data of the map data device, and outputs the relative position information between the vehicle and the objects to the first position information acquisition unit 15. The first position information acquisition unit 15 transmits the acquired first relative position information to the first difference calculation unit 21 and the object position calculation unit 26.

[0124] The first identifier 11 uses existing technologies such as the collation of satellite positioning information and map data, and an autonomous navigation algorithm using an inertial sensor and a speedometer. If the identification of the relative position information to the object by the first identifier 11 fails, the first relative position information is stored as an invalid value. For example, when the satellite positioning information is invalid, when the inertial sensor and the speedometer have stopped functioning, or when driving in an area where map data does not exist, it is determined that the first relative position information is an invalid value.

[0125] According to the object position calculation device 100 according to the fifth embodiment, since the first identifier 11 is composed of the inertial sensor and speedometer 12, the satellite positioning device 13, and the map database 14, compared with the case of using external monitoring sensors such as an image sensor, a radio wave sensor, and an optical sensor, the frequency of acquisition failure of relative position information due to measurement environments such as a decrease in the amount of light around the object and the presence of obstacles can be reduced.

[0126] 6. Embodiment 6 <Configuration of the object position calculation device> FIG. 14 is a configuration diagram of the object position calculation device 100 according to the sixth embodiment. It is different from the configuration diagram of FIG. 1 according to the first embodiment in that the output is specified as the relative distance between the moving body and the fixed object in FIG. 14. Since the relative distance between the vehicle and the object is an extremely important factor in the operation of the vehicle, it is important to obtain a highly accurate relative distance by correction. The hardware configuration diagram of FIG. 3 is also applicable to the sixth embodiment.

[0127] <Distance from the division line> FIG. 15 is a diagram showing an example of the relative position with respect to an object according to Embodiment 6. For example, when the moving object is the vehicle 50 and the object is a division line representing the boundary of a driving lane on a motor vehicle road, it is shown. The first relative position information acquired by the first position information acquisition unit 15 identified by the first identifier 11 of the vehicle 50 and the object position calculation device 100 mounted on the vehicle 50 is indicated by a solid line 51. Then, the second relative position information acquired by the second position information acquisition unit 45 identified by the second identifier 41 is indicated by a broken line 52. The first relative distance L1 between the vehicle 50 and the object and the second relative distance L2 are described on the left side of the vehicle 50. The difference ΔL between the first relative distance L1 and the second relative distance L2 is shown.

[0128] The relative distance to the object can be defined as the distance from the representative point of the moving object equipped with the first identifier 11 and the second identifier 41 to the representative point of the object. The relative distance to the object can be defined as the distance from the center of gravity point of the vehicle 50 equipped with the identifier to the division line directly beside the vehicle. Note that the definition of the relative distance between the object and the vehicle 50 is not necessarily limited to the above example.

[0129] The object position calculation device 100 outputs the corrected relative distance to the object. The corrected relative distance to the object is the relative distance to the object identified by the first identifier 11 and the second identifier 41, corrected by a correction value.

[0130] The relative distance to the object that the object position calculation device 100 periodically performs correction processing and outputs is the relative distance to the object in the most recent period. Here, the most recent period can be defined as the past period closest to the current time among the periods when the processing is executed. Note that the input and output of the object position calculation device 100 do not necessarily have to be the relative distance to the object in the most recent period, and the relative distance from the vehicle to the object in a past period from the current time, their average values, etc. may be used as the input and output.

[0131] In the example of FIG. 15, the first position information acquisition unit 15 can acquire relative position information regarding the lane line shape up to a position far from the vehicle. On the other hand, it shows that the second position information acquisition unit 45 can only acquire relative position information regarding the lane line shape up to a position closer than the first position information acquisition unit 15. Also, it is assumed that the calculation accuracy of the lane line shape at a closer position of the first relative position information by the first discriminator 11 is lower than that of the second relative position information by the second discriminator 41. Therefore, it shows that the first relative distance L1 to the lane line based on the output of the first position information acquisition unit 15 and the second relative distance L2 to the lane line based on the output of the second position information acquisition unit 45 are different values.

[0132] The object position calculation device 100 outputs a relative distance calculated by correcting the first relative distance L1 to the lane line acquired from the first position information acquisition unit 15 with respect to the second relative distance L2 to the lane line output from the second position information acquisition unit 45. By using this corrected relative distance, it becomes possible to calculate the relative position of the lane line shape that can utilize both the advantage of the first discriminator 11 that can acquire the lane line shape up to a far position and the advantage of the second discriminator 41 that has high relative position discrimination accuracy at a close position.

[0133] Note that the difference in characteristics between the first discriminator 11 and the second discriminator 41 does not necessarily have to be the same as in the above example. For example, the first discriminator 11 may have high measurement accuracy of the relative distance, while the second discriminator 41 may have high measurement accuracy of the relative angle, etc.

[0134] <Processing of the object position calculation device> FIG. 16 is a first flowchart showing the processing of the object position calculation device 100 according to Embodiment 6. FIG. 17 is a second flowchart showing the processing of the object position calculation device 100. FIG. 17 shows the continuation of the processing in FIG. 16.

[0135] The processes shown in FIGS. 16 and 17 are executed by the arithmetic processing unit of the object position calculation device 100. This process may be executed at regular intervals (for example, every 1 ms). Instead of at regular intervals, it may also be executed by events such as the first discriminator 11 and the second discriminator 41 of the object position calculation device 100 identifying an object.

[0136] The processes in FIGS. 16 and 17 are obtained by replacing the relative position information in the processes of FIGS. 4 and 5 according to Embodiment 1 with relative distances. Since the processes from step S201 to step S215 are similar to the processes from step S101 to step S115, the description thereof is omitted.

[0137] In the object position calculation device 100 according to Embodiment 6, after the updated correction value calculated by the correction value update unit 23 is stored in the correction value storage unit 25, the object position calculation unit 26 corrects the relative distance to the object using the stored correction value. Also, when the difference value of the first position information is an invalid value, the correction value stored in the correction value storage unit 25 is sent to the object position calculation unit 26 without being changed. With this configuration, even when the second position information acquisition unit 45 fails to acquire the relative distance to the object, the corrected relative distance is calculated using the correction value calculated in the past cycle.

[0138] For example, regarding the situation of FIG. 15 described above, the object is a partition line and the second discriminator 41 is a visible light camera. With the configuration of Embodiment 6, even when the measurement of the partition line by the camera fails due to a temporary decrease in the light amount, it is possible to correct the error in the relative distance to the partition line identified by the first discriminator 11.

[0139] That is, with the configuration of Embodiment 6, even when the discriminator temporarily cannot measure valid relative position information, it is possible to reduce the frequency of situations where the estimation accuracy of the relative distance to the object, that is, the vehicle position, decreases.

[0140] 7. Embodiment 7 <Configuration of Object Position Calculation Device> FIG. 18 is a configuration diagram of the object position calculation device 100 according to Embodiment 7. Different from the configuration diagram of FIG. 1 according to Embodiment 1, in FIG. 7, the output specifies the relative angle between the moving body and the fixed object. Since the relative angle between the vehicle and the object is an extremely important factor in the operation of the vehicle, it is important to obtain a highly accurate relative angle by correction. The hardware configuration diagram of FIG. 3 is also applicable to Embodiment 7.

[0141] In the object position calculation device 100 according to Embodiment 1, the relative position information from the vehicle to the object was output. On the other hand, in the object position calculation device 100 according to Embodiment 7, with reference to the front of the vehicle, the relative angle in the direction where the object exists is specified and output.

[0142] For example, when a lane line representing the boundary of a driving lane on a motor vehicle road is taken as the object, the relative angle in the direction where the object exists can be defined as the angle between the extending direction of the lane line around the vehicle and the traveling direction of the vehicle. Also, for example, when a structure having a predetermined orientation is taken as the object, the angle between the orientation of the structure and the traveling direction of the vehicle may be used as the relative position information. Thus, it is also extremely important for the operation of the vehicle, similar to Embodiment 1, to obtain the relative angle specified and corrected as the relative angle among the relative position information.

[0143] Regarding the configuration diagram of the object position calculation device 100 according to Embodiment 7, the differences from FIG. 1 according to Embodiment 1 are described. The first position information acquisition unit 15 transmits the relative angle (first relative angle) to the object acquired by the first position information acquisition unit 15 in the current cycle to the first difference calculation unit 21 and the object position calculation unit 26. The second position information acquisition unit 45 transmits the relative angle (second relative angle) to the object acquired by the second position information acquisition unit 45 in the current cycle to the first difference calculation unit 21. Regarding the other processing blocks, it is the same as the case where the relative position information in the description of Embodiment 1 is replaced with the relative angle.

[0144] <Processing of the object position calculation device> FIG. 19 is a first flowchart showing the processing of the object position calculation device 100 according to Embodiment 7. FIG. 20 is a second flowchart showing the processing of the object position calculation device 100. FIG. 20 shows the continuation of the processing of FIG. 19.

[0145] The processing shown in FIGS. 19 and 20 is executed by the arithmetic processing unit of the object position calculation device 100. This processing may be executed at predetermined intervals (for example, every 1 ms). Instead of at predetermined intervals, it may be executed by events such as the first discriminator 11 and the second discriminator 41 of the object position calculation device 100 identifying an object.

[0146] The processing in FIGS. 19 and 20 is obtained by replacing the relative position information in the processing of FIGS. 4 and 5 according to Embodiment 1 with relative distances. Since the processing from step S301 to step S315 follows the processing from step S101 to step S115, the description thereof is omitted.

[0147] According to the object position calculation device 100 according to Embodiment 7, after the updated correction value calculated by the correction value update unit 23 is stored in the correction value storage unit 25, the object position calculation unit 26 corrects the relative angle to the object using the stored correction value. Also, when the difference value of the first position information is an invalid value, the correction value stored in the correction value storage unit 25 is sent to the object position calculation unit 26 without being changed. With this configuration, even when the second position information acquisition unit 45 fails to acquire the relative angle to the object, the corrected relative angle can be calculated using the correction value calculated in the past cycle.

[0148] For the situation of FIG. 15 described in Embodiment 6, for example, when the object is a partition line and the second identifier 41 is a visible light camera, in the configuration of Embodiment 7, even if the measurement of the partition line by the camera fails due to a temporary decrease in the amount of light, it is possible to correct the error in the relative angle to the partition line with respect to the first position information acquisition unit 15. That is, with the configuration of Embodiment 7, even when the recognition device temporarily cannot measure effective relative position information, it is possible to reduce the frequency of a situation where the estimation accuracy of the relative angle to the object, that is, the vehicle position, decreases.

[0149] Although various exemplary embodiments and examples are described in the present application, the various features, aspects, and functions described in one or more of the embodiments are not limited to the application of a specific embodiment, but are applicable to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are envisioned within the scope of the technology disclosed in the present specification. For example, it includes cases where at least one component is deformed, added, or omitted, and further cases where at least one component is extracted and combined with the components of other embodiments.

[0150] Hereinafter, aspects of the present disclosure will be collectively described as appendices.

[0151] (Appendix 1) A first identifier that identifies an object existing outside the moving body, A first position information acquisition unit that acquires first relative position information between the fixed object identified by the first identifier and the moving body, A second identifier that identifies the fixed object, A second position information acquisition unit that acquires second relative position information between the fixed object identified by the second identifier and the moving body, A first difference calculation unit that calculates a difference value between the second relative position information of the fixed object acquired by the second position information acquisition unit and the first relative position information of the fixed object acquired by the first position information acquisition unit and outputs it as a difference value of the first position information, A second difference calculation unit that calculates a difference value between the difference value of the first position information output by the first difference calculation unit and the correction value of the previously updated position information, and outputs it as the difference value of the second position information. A correction value update unit that updates the correction value of the position information based on the difference value of the second position information output by the second difference calculation unit, and An object position calculation unit that corrects the first relative position information based on the correction value of the position information updated by the correction value update unit and calculates the relative position information of the fixed object. An object position calculation device comprising: (Appendix 2) A second discriminator accuracy information acquisition unit that acquires the discriminator accuracy information of the second discriminator defined for each road section, The correction value update unit increases the update amount of the correction value of the position information when the accuracy of the discriminator accuracy information acquired by the second discriminator accuracy information acquisition unit is higher than a predetermined accuracy determination value, and the second discriminator accuracy information acquisition unit The object position calculation device according to Appendix 1, wherein when the accuracy of the discriminator accuracy information acquired by is less than or equal to the accuracy determination value, the update amount of the correction value is decreased. (Appendix 3) The second discriminator is an image detector, In the accuracy information of the second discriminator, the discrimination accuracy is set lower than that of other road sections when the road section is a tunnel and a tunnel exit. The object position calculation device according to Appendix 2. (Appendix 4) The first discriminator is a discriminator capable of discriminating a longer distance than the second discriminator. The object position calculation device according to any one of Appendices 1 to 3. (Appendix 5) The first discriminator is a radar device using radio waves, The second discriminator is a discriminator using light. The object position calculation device according to Appendix 4. (Appendix 6) The first discriminator is a discriminator having a higher distance detection accuracy of the fixed object than the second discriminator, The second discriminator is a discriminator having a higher angle detection accuracy of the fixed object than the first discriminator. The object position calculation device according to any one of Appendices 1 to 5. (Appendix 7) It includes a second discriminator accuracy information acquisition unit that acquires the discriminator accuracy information of the second discriminator, When the accuracy of the discriminator accuracy information acquired by the second discriminator accuracy information acquisition unit is lower than a predetermined accuracy determination value, the correction value update unit stops updating the correction value. The object position calculation device according to any one of Appendices 1 to 6. (Appendix 8) It includes a correction prediction unit that predicts a future update value of the correction value based on the history of the correction value updated by the correction value update unit, When the update of the correction value has been stopped for a predetermined determination period, the correction value update unit updates the correction value using the future update value predicted by the correction prediction unit. The object position calculation device according to any one of Appendices 1 to 7. (Appendix 9) It includes a first discriminator accuracy information acquisition unit that acquires the discriminator accuracy information of the first discriminator, The correction prediction unit predicts a future update value of the correction value based on the discriminator accuracy information of the first discriminator acquired by the first discriminator accuracy information acquisition unit and the history of the updated correction value. The object position calculation device according to Appendix 8. (Appendix 10) The first position information acquisition unit acquires the first relative position information of the fixed object based on the current position of the moving object and the position information of the fixed object defined by the map data. The object position calculation device according to any one of Appendices 1 to 4. (Appendix 11) The relative position information includes the distance between the moving object and the fixed object. The object position calculation device according to any one of Appendices 1 to 10. (Appendix 12) The relative position information includes the relative angle between the moving object and the fixed object. The object position calculation device according to any one of Appendices 1 to 10.

Explanation of Reference Signs

[0152] 11 First identifier, 12 Inertial sensor / speedometer, 13 Satellite positioning device, 14, 33 Map database, 15 First position information acquisition unit, 21 First difference calculation unit, 22 Second difference calculation unit, 23 Correction value update unit, 24 Update necessity determination unit, 25 Correction value storage unit, 26 Object position calculation unit, 31 First identifier accuracy information acquisition unit, 32 Second identifier accuracy information acquisition unit, 34 Correction value prediction unit, 41 Second identifier, 45 Second position information acquisition unit, 50 Vehicle, 100 Object position calculation device

Claims

1. A first identifier that identifies a fixed object existing outside the moving body, A first position information acquisition unit that acquires first relative position information between the fixed object identified by the first identifier and the moving body, A second identifier that identifies the fixed object, A second position information acquisition unit that acquires second relative position information between the fixed object identified by the second identifier and the moving body, A first difference calculation unit that calculates a difference value between the second relative position information of the fixed object acquired by the second position information acquisition unit and the first relative position information of the fixed object acquired by the first position information acquisition unit, and outputs it as a difference value of the first position information, A second difference calculation unit that calculates a difference value between the difference value of the first position information output by the first difference calculation unit and a correction value of the previously updated position information, and outputs it as a difference value of the second position information, A correction value update unit that updates the correction value of the position information based on the difference value of the second position information output by the second difference calculation unit, and An object position calculation device including an object position calculation unit that corrects the first relative position information based on the correction value of the position information updated by the correction value update unit and calculates the relative position information of the fixed object.

2. It includes a second identifier accuracy information acquisition unit that acquires the identification accuracy information of the second identifier defined for each road section, The correction value update unit increases the update amount of the correction value of the position information when the accuracy of the identification accuracy information acquired by the second identifier accuracy information acquisition unit is higher than a predetermined accuracy determination value, and decreases the update amount of the correction value when the accuracy of the identification accuracy information acquired by the second identifier accuracy information acquisition unit is equal to or lower than the accuracy determination value. The object position calculation device according to claim 1.

3. The second identifier is an image detector, The object position calculation device according to claim 2, wherein in the accuracy information of the second identifier, the identification accuracy is set lower than that of other road sections when the road section is a tunnel and the tunnel exit.

4. The object position calculation device according to claim 1, wherein the first identifier is an identifier capable of identifying a longer distance than the second identifier.

5. The first identifier is a radar device using radio waves, The object position calculation device according to claim 4, wherein the second identifier is an identifier using light.

6. The first identifier is an identifier having a higher distance detection accuracy for the fixed object than the second identifier, The object position calculation device according to claim 1, wherein the second identifier is an identifier having a higher angle detection accuracy for the fixed object than the first identifier.

7. The object position calculation device according to claim 1, further comprising a second identifier accuracy information acquisition unit that acquires the identification accuracy information of the second identifier, When the accuracy of the identification accuracy information acquired by the second identifier accuracy information acquisition unit is lower than a predetermined accuracy determination value, the correction value update unit stops updating the correction value.

8. The object position calculation device according to claim 1, further comprising a correction prediction unit that predicts a future update value of the correction value based on a history in which the correction value has been updated by the correction value update unit. When the update of the correction value has been stopped for a predetermined determination period, the correction value update unit updates the correction value using the future update value predicted by the correction prediction unit.

9. The object position calculation device according to claim 1, further comprising a first identifier accuracy information acquisition unit that acquires the identification accuracy information of the first identifier, The object position calculation device according to claim 8, wherein the correction prediction unit predicts a future update value of the correction value based on the identification accuracy information of the first identifier acquired by the first identifier accuracy information acquisition unit and the history in which the correction value has been updated.

10. The object position calculation device according to claim 1, wherein the first position information acquisition unit acquires first relative position information of the fixed object based on the current position of the moving object and the position information of the fixed object defined by map data.

11. The object position calculation device according to any one of claims 1 to 10, wherein the relative position information includes a distance between the moving object and the fixed object.

12. The object position calculation device according to any one of claims 1 to 10, wherein the relative position information includes a relative angle between the moving object and the fixed object.

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