JP6901870B2 - Position estimator, control method, and program - Google Patents

Description

The present invention relates to position estimation devices, control methods, and programs.

In order to control the running of the vehicle by a computer, a technique for estimating the position where the vehicle is currently running has been developed. Such position estimation is called own vehicle position estimation (localization). Non-Patent Document 1 discloses a technique for performing position estimation using a probability distribution.

Sebastian Thrun, 2 outsiders, "Probabilistic Robotics", The MIT Press, August 19, 2005

Vehicle position estimation is realized by detecting landmarks (buildings, etc.) in the vicinity where the position on the map is known with a sensor. Therefore, if the sensor cannot detect the landmark due to the presence of an obstacle or the like, the accuracy of the vehicle position estimation will decrease.

The present invention has been made in view of the above problems, and one object of the present invention is to provide a technique for estimating the position of a vehicle with high accuracy.

The invention according to claim 1 is an invention of a position estimation device. The position estimation device includes (1) an acquisition means for acquiring vehicle position information which is information on the position of the second vehicle from a second vehicle existing around the first vehicle, and (2) the first vehicle. Relative position specifying means for calculating the relative position of the second vehicle with respect to the first vehicle using the measured values of the provided sensors, and (3) vehicle position information acquired from the second vehicle. and using the relative position of the second vehicle relative to the first vehicle, it has a, and estimated position calculating means for calculating the estimated position of the first vehicle,
The vehicle position information indicates a relative position of a landmark with respect to the second vehicle, which is measured by a sensor provided in the second vehicle.
The estimated position calculation means
Using the relative position of the landmark based on the second vehicle and the relative position of the second vehicle based on the first vehicle shown in the vehicle position information, the first vehicle is used as a reference. Identify the relative position of the landmark,
The estimated position of the first vehicle is calculated using the relative position of the landmark with respect to the specified first vehicle .

The invention of claim 1 0 is an invention of a control method to be executed by a computer. The control method is provided in (1) an acquisition step of acquiring vehicle position information which is information on the position of the second vehicle from a second vehicle existing around the first vehicle, and (2) the first vehicle. A relative position specifying step for calculating the relative position of the second vehicle with respect to the first vehicle using the measured values of the sensors, (3) vehicle position information acquired from the second vehicle, and by using the relative position of the second vehicle relative to the first vehicle, it has a, and the estimated position calculation step of calculating an estimated position of the first vehicle,
The vehicle position information indicates a relative position of a landmark with respect to the second vehicle, which is measured by a sensor provided in the second vehicle.
In the estimated position calculation step,
Using the relative position of the landmark based on the second vehicle and the relative position of the second vehicle based on the first vehicle shown in the vehicle position information, the first vehicle is used as a reference. Identify the relative position of the landmark,
The estimated position of the first vehicle is calculated using the relative position of the landmark with respect to the specified first vehicle .

The invention of claim 1 1 is an invention of a program for executing the steps of the control method according to claim 10 in a computer.

It is a figure for demonstrating a part of the operation of the position estimation apparatus of Embodiment 1. FIG. It is a figure which compares an absolute position and a relative position. It illustrates how the sensor cannot detect landmarks due to the presence of obstacles. It is a figure which conceptually shows the method of treating a landmark detected by a peripheral vehicle as a target landmark. It is a figure which conceptually shows the method of treating a peripheral vehicle as a target landmark. It is a block diagram which illustrates the functional structure of the position estimation apparatus which concerns on Embodiment 1. FIG. It is a figure which illustrates the hardware composition of the position estimation apparatus. It is a figure which illustrates the position estimation device installed inside the target vehicle. It is a flowchart which illustrates the flow of the process executed by the position estimation apparatus of Embodiment 1. FIG. It is a figure which illustrates the state that the peripheral vehicle is detected by the sensor. It is a figure which illustrates the method of calculating the relative position of the peripheral vehicle with respect to the target vehicle using the point cloud data of the peripheral vehicle and the vehicle information. It is a figure which illustrates the matching using the posture of the target vehicle and the peripheral vehicle. It is a flowchart which illustrates the whole flow of own vehicle position estimation performed by a position estimation device. It is a figure for demonstrating that it is necessary to grasp the relationship between the posture of a target vehicle and the posture of a peripheral vehicle. It is a figure which illustrates the correspondence between the vehicle position information of each peripheral vehicle, and the relative position of each peripheral vehicle with respect to a target vehicle. It is a figure which illustrates the state of specifying the size of a peripheral vehicle by a sensor. It is a flowchart which exemplifies the flow of the process which determines what to treat as a target landmark.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are designated by the same reference numerals, and description thereof will be omitted as appropriate. Further, unless otherwise specified, each block in the block diagram represents a configuration of a functional unit, not a configuration of a hardware unit.

<Overview>
FIG. 1 is a diagram for explaining a part of the operation of the position estimation device 200 of the first embodiment. The position estimation device 200 is a device that estimates the position of the target vehicle 10 (first vehicle). For example, the target vehicle 10 is an autonomous driving vehicle. In an autonomous vehicle, the position of the own vehicle is estimated (localization) by a computer (for example, an ECU (Electronic Control Unit)), and the traveling is controlled by using the estimated position of the own vehicle. The position estimation device 200 has a function of estimating the position of the own vehicle. In the following, the estimated position of the target vehicle 10 will also be referred to as the estimated position of the target vehicle 10.

The target vehicle 10 may be a vehicle controlled by using the own vehicle position estimated by the position estimation device 200, and is not limited to the autonomous driving vehicle. For example, the target vehicle 10 may be a vehicle having a feature that "in normal times, it is manually operated by a driver, and in an emergency, control such as collision avoidance based on an estimated position is performed".

The estimated position of the target vehicle 10 is represented, for example, as an absolute position on a specific map used for controlling the target vehicle 10. Hereinafter, this map will be referred to as an environmental map. The absolute position in the present specification means a position with respect to the origin in the coordinate space of the environmental map. On the other hand, a position in a coordinate system determined with reference to a certain object (for example, the target vehicle 10) is called a relative position with respect to that object.

FIG. 2 is a diagram comparing the absolute position and the relative position. The coordinate system on the environmental map is the XYZ coordinate system. On the other hand, the coordinate system based on the target vehicle 10 is the UVW coordinate system. In addition, in order to make the figure easier to see, the notation of the Z axis and the notation of the W axis are omitted in FIG.

In FIG. 2, the absolute position of point Q is (x1, y1, z1). On the other hand, the relative position of the point Q with respect to the target vehicle 10 is (u1, v1, w1). The coordinate system determined with reference to the target vehicle 10 is determined by the position and posture (orientation) of the target vehicle 10. For example, in FIG. 2, the coordinate system determined with reference to the target vehicle 10 has the position of the target vehicle 10 as the origin, the front direction of the target vehicle 10 as the U-axis direction, and the right side of the target vehicle 10 as the V-axis direction. This is a coordinate system with the vertical direction at the position of the vehicle 10 as the W axis.

Generally, the vehicle's own position is estimated by detecting surrounding landmarks with a sensor such as a lidar (Light Detection and Ranging). The landmark to be detected here is an arbitrary object whose absolute position on the environmental map is fixed or estimated. For example, as a landmark, a building, a road sign, a traffic light, or the like is adopted. Hereinafter, the landmark used for estimating the position of the own vehicle will be referred to as a target landmark.

Specifically, first, the relative position of each target landmark around the vehicle is specified with respect to the vehicle by using the measurement result by the sensor. Then, the estimated position of the vehicle is calculated (updated) by using the relative position of the target landmark with respect to the vehicle, the absolute position of the target landmark on the environmental map, and the current estimated position of the vehicle. .. The initial value of the estimated position of the vehicle is determined by using, for example, GPS coordinates obtained by a GPS (Global Positioning System) sensor.

The position estimation device 200 identifies the relative position of the landmark 30 with respect to the target vehicle 10 by using the measurement result of the sensor 12 provided on the target vehicle 10. The absolute position of the landmark 30 on the environmental map has been determined or estimated.

In FIG. 1, the landmark 30 exists at the absolute position L on the environmental map. The current estimated position of the target vehicle 10 is A. The position estimation device 200 uses the landmark 30 as a target landmark. The position estimation device 200 identifies the relative position Z of the landmark 30 with respect to the target vehicle 10 based on the measurement result of the sensor 12. For example, when a rider is used as the sensor 12, light used for measurement (hereinafter referred to as measurement light) is output from the rider, the measurement light is reflected by a landmark, and the reflected light is received by the rider. The relative position of the landmark 30 with respect to the target vehicle 10 is specified based on the direction in which the measurement light is output and the time from the output of the measurement light to the reception of the reflected light.

The position estimation device 200 uses the relative position Z of the landmark 30 with respect to the target vehicle 10, the absolute position L of the landmark 30 on the environmental map, and the current estimated position A of the target vehicle 10, and the target vehicle 10 Calculate the new estimated landmark A ^ (update the estimated landmark). That is, in order to calculate the estimated position A ^ of the target vehicle 10, (1) the absolute position of the target landmark and (2) the relative position of the target landmark based on the target vehicle 10 are required. The specific calculation method of the estimated position of the target vehicle 10 will be described later.

Here, depending on the situation, the sensor 12 may not be able to detect the landmark 30. For example, if the measurement light does not reach the landmark 30 due to an obstacle between the sensor 12 and the landmark 30, the landmark 30 is not detected.

FIG. 3 illustrates how the sensor 12 cannot detect the landmark 30 due to the presence of an obstacle. In FIG. 3, a peripheral vehicle 20 (second vehicle) exists between the position estimation device 200 and the landmark 30. The measurement light output from the sensor 12 is reflected by the peripheral vehicle 20 and has not reached the landmark 30. Therefore, the position estimation device 200 cannot detect the landmark 30. For example, when the peripheral vehicle 20 is a large vehicle such as a dump truck or a tank truck, there is a high possibility that the measurement light will be blocked by the peripheral vehicle 20.

If the landmark 30 cannot be detected due to the presence of the peripheral vehicle 20 in this way, the accuracy of the own vehicle position estimation may decrease. Therefore, in order to deal with the situation where there is a landmark 30 that cannot be detected due to the presence of the peripheral vehicle 20, the position estimation device 200 of the present embodiment uses the peripheral vehicle 20 that can be detected by the sensor 12 to estimate the position of the own vehicle. .. In this way, when there are landmarks 30 that cannot be detected by the sensor 12, there are landmarks 30 that cannot be detected by the sensor 12 by estimating the position of the own vehicle using the peripheral vehicle 20 that can be detected by the sensor 12. However, it is possible to estimate the position of the own vehicle with high accuracy.

For example, the position estimation device 200 uses the peripheral vehicle 20 to (1) treat the landmark 30 detected by the peripheral vehicle 20 as a target landmark, or (2) treat the peripheral vehicle 20 as a target landmark. Therefore, the position estimation device 200 acquires information related to the position of the peripheral vehicle 20 from the peripheral vehicle 20. Hereinafter, this information will be referred to as vehicle position information.

When the landmark 30 detected by the peripheral vehicle 20 is treated as the target landmark, for example, the vehicle position information is a landmark based on the peripheral vehicle 20 identified from the measurement result by the sensor provided in the peripheral vehicle 20. 30 relative positions are shown.

FIG. 4 is a diagram conceptually showing a method of treating a landmark 30 detected by a peripheral vehicle 20 as a target landmark. The absolute position of the landmark 30 (absolute position of the target landmark) L can be specified by using the environmental map. The relative position of the landmark 30 based on the target vehicle 10 (relative position of the target landmark based on the target vehicle 10) is the relative position Z2 of the peripheral vehicle 20 based on the target vehicle 10 and the peripheral vehicle 20. It can be specified by using the relative position Z1 of the reference landmark 30. The relative position Z1 of the landmark 30 with respect to the peripheral vehicle 20 can be specified by the vehicle position information.

According to this method, the landmark 30 that cannot be directly detected by the sensor 12 can be used as a landmark used for estimating the position of the own vehicle. Therefore, even if the landmark 30 cannot be directly detected by using the sensor 12, the vehicle position can be estimated with high accuracy.

When the peripheral vehicle 20 is treated as a target landmark, for example, the vehicle position information indicates the absolute position of the peripheral vehicle 20 on the environmental map. In this case, it is assumed that the peripheral vehicle 20 also has a function of estimating the position of the own vehicle. Then, the absolute position of the peripheral vehicle 20 is calculated as a result of estimating the position of the own vehicle in the peripheral vehicle 20.

FIG. 5 is a diagram conceptually showing a method of treating the peripheral vehicle 20 as a target landmark. As for the vehicle position information, the absolute position (absolute position of the target landmark) B of the surrounding vehicles 20 can be specified by the vehicle position information. The relative position (relative position of the target landmark based on the target vehicle 10) Z of the peripheral vehicle 20 with respect to the target vehicle 10 can be specified by using the measurement result by the sensor 12.

According to this method, the peripheral vehicle 20 can be treated as if it were a landmark such as a building or a sign, and the estimated position of the target vehicle 10 can be calculated. Therefore, even if the landmark 30 whose absolute position is determined or estimated in advance cannot be detected on the environmental map, the position of the own vehicle can be estimated with high accuracy.

Hereinafter, the position estimation device 200 of the present embodiment will be described in more detail.

<Example of functional configuration of position estimation device 200>
FIG. 6 is a block diagram illustrating the functional configuration of the position estimation device 200 according to the first embodiment. The position estimation device 200 has an acquisition unit 202, a relative position identification unit 204, and an estimation position calculation unit 206. The acquisition unit 202 acquires vehicle position information from the peripheral vehicle 20. The relative position specifying unit 204 calculates the relative position of the peripheral vehicle 20 with respect to the target vehicle 10 by using the measurement result of the sensor 12. The estimated position calculation unit 206 calculates the estimated position of the target vehicle 10 by using the acquired vehicle position information and the calculated relative position.

<Example of hardware configuration of position estimation device 200>
Each functional component of the position estimation device 200 may be realized by hardware that realizes each functional component (eg, a hard-wired electronic circuit, etc.), or a combination of hardware and software (eg, example). It may be realized by a combination of an electronic circuit and a program that controls it). Hereinafter, a case where each functional component of the position estimation device 200 is realized by a combination of hardware and software will be further described.

FIG. 7 is a diagram illustrating a hardware configuration of the position estimation device 200. The computer 100 is a computer that realizes the position estimation device 200. For example, the computer 100 is an ECU (Electronic Control Unit) that controls the engine of the target vehicle 10. The computer 100 may be a computer specially designed to realize the position estimation device 200, or may be a general-purpose computer.

The computer 100 has a bus 102, a processor 104, a memory 106, a storage device 108, an input / output interface 110, and a network interface 112. The bus 102 is a data transmission line for the processor 104, the memory 106, the storage device 108, the input / output interface 110, and the network interface 112 to transmit and receive data to and from each other. However, the method of connecting the processors 104 and the like to each other is not limited to the bus connection. The processor 104 is an arithmetic processing unit realized by using a microprocessor or the like. The memory 106 is a main storage device realized by using RAM (Random Access Memory) or the like. The storage device 108 is an auxiliary storage device realized by using a ROM (Read Only Memory), a flash memory, or the like.

The input / output interface 110 is an interface for connecting the computer 100 to peripheral devices. For example, various analog signals and digital signals used for controlling the engine of the target vehicle 10 and the like are input or output to the computer 100 via the input / output interface 110. Here, the input / output interface 110 appropriately includes an A / D converter that converts an analog input signal into a digital signal, a D / A converter that converts a digital output signal into an analog signal, and the like.

The network interface 112 is an interface for connecting the computer 100 to the communication network. This communication network is, for example, a CAN (Controller Area Network) communication network. The method of connecting the network interface 112 to the communication network may be a wireless connection or a wired connection.

The computer 100 may have a plurality of network interfaces 112. For example, the computer 100 has a network interface 112 for connecting to a CAN communication network and a network interface 112 for connecting to a WAN (Wide Area Network) communication network. For example, the computer 100 acquires speed control information, map information, and the like from an external device via a WAN communication network. The external device is, for example, a server that manages speed control information and map information. However, the map information and the speed control information may be stored inside the computer 100 (for example, the storage device 108).

The storage device 108 stores a program module for realizing each functional component of the position estimation device 200. The processor 104 realizes the function of the position estimation device 200 by reading the program module into the memory 106 and executing the program module.

<Installation example of position estimation device 200>
The position estimation device 200 is installed in, for example, the target vehicle 10. FIG. 8 is a diagram illustrating a position estimation device 200 installed inside the target vehicle 10. The ECU 240 is a computer that realizes the position estimation device 200. The target vehicle 10 is a vehicle whose traveling is controlled by using the estimated position calculated by the ECU 240. For example, the running of the target vehicle 10 is controlled by controlling mechanisms such as gears, engines, and steering. It should be noted that the existing technology is used for the technology of determining the vehicle running control method based on the estimation result of the own vehicle position and controlling various mechanisms provided in the vehicle based on the determined control method. can do.

<Processing flow>
FIG. 9 is a flowchart illustrating a flow of processing executed by the position estimation device 200 of the first embodiment. The acquisition unit 202 acquires vehicle position information from the peripheral vehicle 20 (S102). The relative position specifying unit 204 identifies the relative position of the peripheral vehicle 20 with respect to the target vehicle 10 by using the measurement result by the sensor 12 (S104). The estimated position calculation unit 206 calculates the estimated position of the target vehicle 10 by using the vehicle position information acquired in S102 and the relative position calculated in S104 (S106).

The above-mentioned process is executed, for example, when the landmark 30 existing around the target vehicle 10 on the environmental map cannot be detected by the sensor 12. Therefore, for example, the position estimation device 200 determines whether or not the landmark 30 existing around the target vehicle 10 can be detected by the sensor 12 on the environment map. When the landmark 30 cannot be detected by the sensor 12, the position estimation device 200 calculates the estimated position of the target vehicle 10 according to the flow shown in FIG. On the other hand, when the landmark 30 can be detected by the sensor 12, the position estimation device 200 determines the absolute position of the landmark 30 on the environmental map and the landmark for the target vehicle 10 specified by the measurement result of the sensor 12. The estimated position of the target vehicle 10 is calculated using the relative positions of 30 (see FIG. 1).

In addition, for example, in calculating the estimated position of the target vehicle 10, it is preferable that a predetermined number or more of target landmarks can be obtained. In this case, the position estimation device 200 may perform the process of FIG. 9 when the number of landmarks 30 detected by the sensor 12 is less than the predetermined number. In this case, in addition to the landmark 30 detected by the sensor 12, the landmark 30 detected by the peripheral vehicle 20 or the peripheral vehicle 20 is used as the target landmark in the calculation of the estimated position of the target vehicle 10.

<Acquisition of vehicle position information: S102>
The acquisition unit 202 acquires vehicle position information from the peripheral vehicle 20 (S102). Any communication method can be used to acquire the vehicle position information. For example, so-called vehicle-to-vehicle communication can be used. Existing technology can be used as the technology for acquiring information from other vehicles through vehicle-to-vehicle communication.

Here, when the vehicle position information indicates the relative position of the landmark 30 with respect to the peripheral vehicle 20, the position estimation device 200 needs to specify which landmark in the environmental map the landmark 30 is. .. Therefore, for example, the vehicle position information includes information for identifying the landmark 30 in addition to the relative position of the landmark 30 with respect to the peripheral vehicle 20. The information that identifies the landmark 30 is, for example, the absolute position of the landmark 30 on the environmental map. In addition, for example, when the same identifier is assigned to the same landmark in the environmental map used by the target vehicle 10 and the environmental map used by the peripheral vehicle 20, the information for identifying the landmark 30 can be obtained. It may be an identifier assigned to landmark 30 on the environmental map.

When there are a plurality of peripheral vehicles 20 around the target vehicle 10, the acquisition unit 202 needs to specify from which peripheral vehicle 20 the acquired vehicle position information is transmitted. This specific need and implementation method will be described later.

<Specification of Relative Position of Peripheral Vehicle 20 with reference to Target Vehicle 10: S104>
The relative position specifying unit 204 specifies the relative position of the peripheral vehicle 20 with respect to the target vehicle 10 (S104). The technology for identifying the relative position of the peripheral vehicle 20 with respect to the target vehicle 10 using the measurement result by the sensor 12 is an existing technology for identifying the position of surrounding buildings and obstacles using a sensor such as a rider. Can be used.

Here, in general, a sensor used for estimating the position of the own vehicle detects landmarks and surrounding vehicles by outputting measurement light in various directions around the own vehicle. Then, the measurement result by the sensor is often obtained for a plurality of positions on the outer circumference of the surrounding vehicle. FIG. 10 is a diagram illustrating how the peripheral vehicle 20 is detected by the sensor. In FIG. 10, the sensor 12 irradiates the measurement light while changing the irradiation direction, and measures the distance by receiving the reflected light. The measurement light emitted from the sensor 12 is applied to six places on the outer circumference of the peripheral vehicle 20. Therefore, as the measurement result by the sensor 12, the relative positions of these six locations with respect to the target vehicle 10 can be obtained. Hereinafter, the relative positions with respect to the target vehicle 10 obtained for a plurality of locations on one peripheral vehicle 20 in this way will be referred to as point cloud data of the peripheral vehicle 20.

Therefore, for example, the relative position specifying unit 204 specifies the relative position of the peripheral vehicle 20 with respect to the target vehicle 10 from the point cloud data of the peripheral vehicle 20. There are various ways to identify it. For example, the relative position specifying unit 204 arbitrarily selects one position included in the point cloud data of the peripheral vehicle 20, and sets this selected position as the relative position of the peripheral vehicle 20 with respect to the target vehicle 10. .. In addition, for example, the relative position specifying unit 204 calculates the position of the center (center of gravity, circumcenter, inner center, etc.) of the polygon having each position included in the point cloud data of the peripheral vehicle 20 as the apex, and calculates the position of the center. The position is the relative position of the peripheral vehicle 20 with respect to the target vehicle 10.

In addition, for example, the relative position specifying unit 204 acquires information on the shape and reference position of the peripheral vehicle 20, and uses this information and the point cloud data of the peripheral vehicle 20 to refer to the target vehicle 10. The relative position of the peripheral vehicle 20 may be determined. Specifically, the vehicle position information provided by the peripheral vehicle 20 includes information that can specify the shape and the reference position of the peripheral vehicle 20. The position estimation device 200 converts the reference position of the peripheral vehicle 20 into a relative position with respect to the target vehicle 10 by matching the point cloud data with the shape of the peripheral vehicle 20. Then, the relative position specifying unit 204 sets the position obtained by this conversion as the relative position of the peripheral vehicle 20 with respect to the target vehicle 10. For the above matching, an algorithm such as ICP (Interactive Closest Point) can be used.

FIG. 11 is a diagram illustrating a method of calculating the relative position of the peripheral vehicle 20 with respect to the target vehicle 10 by using the point cloud data of the peripheral vehicle 20 and the vehicle information. First, from the detection result of the sensor 12, point cloud data including six positions can be obtained. Further, from the vehicle information, the shape and the reference position of the peripheral vehicle 20 can be obtained. Here, by matching the shape of the peripheral vehicle 20 with the point cloud data, the shape and the reference position of the peripheral vehicle 20 are mapped to the coordinate system with respect to the target vehicle 10. The relative position specifying unit 204 treats the reference position of the peripheral vehicle 20 mapped to the coordinate system based on the target vehicle 10 as the relative position of the peripheral vehicle 20 based on the target vehicle 10.

Here, the information that can specify the shape of the peripheral vehicle 20 may be information that directly indicates the shape of the peripheral vehicle 20 or information that can be used to obtain the shape of the peripheral vehicle 20. For example, in the latter case, the vehicle type of the peripheral vehicle 20 can be used as information that can specify the shape of the peripheral vehicle 20. The relative position specifying unit 204 acquires the shape corresponding to the vehicle type shown in the vehicle information from the database in which the vehicle type and the vehicle shape of the vehicle type are associated with each other. This database is provided, for example, by car manufacturers.

In addition, in order to improve the accuracy of matching between the point cloud data and the shape of the peripheral vehicle 20, the postures of the target vehicle 10 and the peripheral vehicle 20 may be used. Generally, in an autonomous vehicle, in addition to estimating the position of the vehicle on the environmental map, the posture of the vehicle on the environmental map is also estimated. Therefore, for example, it is assumed that the posture of the vehicle on the environmental map is estimated even in the target vehicle 10 and the peripheral vehicle 20.

The estimated position calculation unit 206 acquires the posture of the target vehicle 10 on the environmental map estimated by the target vehicle 10. Further, the estimated position calculation unit 206 acquires the posture of the peripheral vehicle 20 on the environmental map estimated by the peripheral vehicle 20. It is assumed that the information indicating the posture of the peripheral vehicle 20 is included in the vehicle information.

Further, the estimation position calculation unit 206 specifies the posture of the peripheral vehicle 20 in the coordinate system based on the target vehicle 10 based on the posture of the target vehicle 10 and the posture of the peripheral vehicle 20 on the environmental map. For example, assume that the posture of the target vehicle 10 on the environmental map is S1 degree rotation from the X axis, and the posture of the peripheral vehicle 20 on the environmental map is S2 degree rotation from the X axis. In this case, the posture of the peripheral vehicle 20 in the UVW coordinate system with respect to the target vehicle 10 is the posture rotated (S2-S1) degrees from the U axis.

The estimation position calculation unit 206 matches the point cloud data with the shape of the peripheral vehicle 20 by using the posture of the peripheral vehicle 20 with reference to the target vehicle 10 thus obtained. FIG. 12 is a diagram illustrating matching using the postures of the target vehicle 10 and the peripheral vehicles 20. As described above, the relative position specifying unit 204 specifies the posture of the peripheral vehicle 20 in the coordinate system with respect to the target vehicle 10. Then, the relative position specifying unit 204 matches the shape of the peripheral vehicle 20 obtained from the vehicle information with the point cloud data in this specified posture. This method is particularly suitable, for example, in the case where the number of positions (locations on the peripheral vehicle 20 detected by the sensor 12) included in the point cloud data is small.

The posture of the peripheral vehicle 20 in the coordinate system based on the target vehicle 10 may be used as the initial posture of the matching process. In this case, the posture of the peripheral vehicle 20 obtained as a result of the matching process does not necessarily have to match the initial posture.

The method of acquiring the posture of the target vehicle 10 or the peripheral vehicle 20 on the environmental map is not limited to the above-mentioned method of acquiring the posture estimated in advance by the target vehicle 10 or the peripheral vehicle 20. For example, the estimated position calculation unit 206 may specify the posture of the target vehicle 10 on the environmental map based on the detection results of the plurality of landmarks 30 and the positions of the landmarks 30 on the environmental map. In addition, for example, the estimation position calculation unit 206 matches the shape of the landmark 30 detected by the sensor 12 with the shape and posture of the landmark 30 registered in the environment map in advance, thereby displaying the landmark 30 on the environment map. The posture of the target vehicle 10 in the above may be specified. In addition, for example, the target vehicle 10 is on the environmental map by matching the white lines and sidewalks detected by the camera installed in the target vehicle 10 with the white lines and sidewalks on the environmental map. The posture of the target vehicle 10 may be detected. The same applies to the method by which the peripheral vehicle 20 specifies the posture of the peripheral vehicle 20 on the environmental map.

<Calculation of estimated position of target vehicle 10: S106>
The estimated position calculation unit 206 calculates the estimated position A ^ of the target vehicle 10 by using the vehicle position information acquired in S102 and the relative position of the peripheral vehicle 20 specified in S104 (S106). Here, in general, the estimation of the own vehicle position of the vehicle is performed by expressing the own vehicle position by a probability distribution and repeatedly updating this probability distribution. Hereinafter, the probability distribution of the estimated position of the target vehicle 10 is referred to as P (a).

Here, in general, the update of the probability distribution of the estimated position of the vehicle consists of two processes: (1) a first update process that reflects the movement of the vehicle, and (2) a second update process that reflects the detection result of the target landmark. This is achieved by repeatedly executing a set of update processes.

FIG. 13 is a flowchart illustrating the overall flow of own vehicle position estimation performed by the position estimation device 200. The position estimation device 200 calculates the initial value of the estimated position of the target vehicle 10 (S202). After that, the position estimation device 200 repeatedly executes the loop process A including the first update process (S204) and the second update process (S206).

There are various triggers when the execution of the loop process A ends, that is, when the position estimation device 200 finishes estimating the position of the own vehicle. For example, the loop process A ends when the power supply of the target vehicle 10 or the engine is stopped.

P(a^) は、第２の更新処理の結果として算出される車両の推定位置の確率分布である。P(a^) は、ベイズ推定における事後分布に相当する。一方、P(a) は、第２の更新処理が行われる前の車両の推定位置の確率分布である。P(a) は、ベイズ推定における事前分布に相当する。Zi は、車両を基準とする対象ランドマークｉの相対位置を表す。数式（１）では、確率分布 p(a) の更新に、n 個の対象ランドマークが利用されている。n は１以上の任意の整数である。ただし、n は２以上であることが好適である。以下、P(Z1,...,Zn|a) を、P(Z|a) とも表記する。 The relative position of the target landmark with respect to the vehicle is used in the second update process described above. For the second update process, for example, Bayesian inference is used. The second update process using Bayesian inference is represented by, for example, the following mathematical formula (1).

P (a ^) is the probability distribution of the estimated position of the vehicle calculated as a result of the second update process. P (a ^) corresponds to the posterior distribution in Bayesian inference. On the other hand, P (a) is the probability distribution of the estimated position of the vehicle before the second update process is performed. P (a) corresponds to the prior distribution in Bayesian inference. Zi represents the relative position of the target landmark i with respect to the vehicle. In equation (1), n target landmarks are used to update the probability distribution p (a). n is any integer greater than or equal to 1. However, it is preferable that n is 2 or more. Hereinafter, P (Z1, ..., Zn | a) is also referred to as P (Z | a).

The estimated position calculation unit 206 calculates the estimated position A ^ of the target vehicle 10 from the calculated probability distribution P (a ^) of the estimated position of the target vehicle 10. Existing technology can be used as a technique for calculating the estimated position of the own vehicle position from the probability distribution of the estimated position of the own vehicle position. For example, the estimated position calculation unit 206 sets the position where the probability is maximum in the probability distribution P (a ^) as the estimated position A ^ of the target vehicle 10.

Here, in the mathematical formula (1), P (Z | a), which is the likelihood of the estimated position A of the vehicle, is based on (a) the absolute position Li of each target landmark i and (b) the target vehicle 10. It is calculated using the relative position of each target landmark i.

It is assumed that the target landmark is a landmark (signboard, etc.) whose position is determined on the environmental map, and that it can be directly observed by a sensor provided on the target vehicle 10. In this case, the estimated position calculation unit 2060 specifies the absolute position of the target landmark by using the environment map. Further, the estimated position calculation unit 2060 specifies the relative position of the target landmark with respect to the target vehicle 10 based on the measurement result of the sensor provided on the target vehicle 10.

On the other hand, when the target landmark is the landmark 30 detected by the peripheral vehicle 20, or the peripheral vehicle 20 is the target landmark, the estimated position calculation unit 206 uses the vehicle position information acquired by the acquisition unit 202. Using the relative positions of the peripheral vehicles 20 relative to the target vehicle 10 specified by the relative position specifying unit 204, (a) the absolute position of the target landmark and (b) the target land based on the target vehicle 10. Identify the relative position of the mark.

Hereinafter, each of the above-mentioned (a) and (b) identification methods will be described for each of the case where the target landmark is the peripheral vehicle 20 and the case where the target landmark is the landmark 30 detected by the peripheral vehicle 20. ..

<< Case of peripheral vehicle 20 >>
In this case, the vehicle position information indicates the estimated position of the peripheral vehicle 20. Therefore, the estimated position calculation unit 206 treats the estimated position of the peripheral vehicle 20 shown in the vehicle position information as the absolute position L of the target landmark on the environmental map. Further, the estimated position calculation unit 206 treats the relative position of the peripheral vehicle 20 with respect to the target vehicle 10 as the relative position Z of the target landmark with reference to the target vehicle 10 specified by the relative position specifying unit 204. From the above, the above-mentioned (a) and (b) are specified.

As a specific method for realizing the second update process represented by the mathematical formula (1), various methods using an extended Kalman filter, a particle filter, or the like can be adopted.

<< Case of landmark 30 detected by peripheral vehicle 20 >>
First, the estimated position calculation unit 206 acquires the absolute position L of the landmark 30 on the environmental map from the environmental map. By doing this, the absolute position of the target landmark is specified.

Next, the estimated position calculation unit 206 uses the vehicle information to specify the relative position of the target landmark (landmark 30) with respect to the target vehicle 10. The vehicle position information in this case includes the relative position of the landmark 30 with respect to the peripheral vehicle 20. The estimated position calculation unit 206 is a relative position of the peripheral vehicle 20 based on the target vehicle 10 calculated by the relative position identification unit 204 and a relative position of the landmark 30 based on the peripheral vehicle 20 shown in the vehicle position information. And are used to calculate the relative position of the landmark 30 with respect to the target vehicle 10.

Here, in order to specify the relative position of the landmark 30 with respect to the target vehicle 10, it is necessary to specify the posture of the peripheral vehicle 20 in the coordinate system with respect to the target vehicle 10. FIG. 14 is a diagram for explaining that it is necessary to grasp the posture of the peripheral vehicle 20 in the coordinate system with respect to the target vehicle 10. The position of the peripheral vehicle 20 in the coordinate system with respect to the target vehicle 10 can be specified from the detection result of the sensor provided on the target vehicle 10.

Here, it is assumed that the posture of the peripheral vehicle 20 in the coordinate system based on the target vehicle 10 cannot be specified. In this case, the position of the landmark 30 detected by the sensor provided in the peripheral vehicle 20 is not uniquely determined in the coordinate system with respect to the target vehicle 10. For example, when the sensor provided in the peripheral vehicle 20 finds that the distance between the peripheral vehicle 20 and the landmark 30 is d, the position of the peripheral vehicle 20 in the coordinate system with respect to the target vehicle 10 is determined. It will be somewhere on the circumference of a radius d centered on the peripheral vehicle 20.

Therefore, the estimated position calculation unit 206 determines the relative position of the peripheral vehicle 20 based on the target vehicle 10, the relative position of the landmark 30 based on the peripheral vehicle 20, and the peripheral vehicle 20 in the coordinate system based on the target vehicle 10. The position of the landmark 30 with respect to the target vehicle 10 is specified by using the posture of.

Here, a method of specifying the posture of the peripheral vehicle 20 in the coordinate system with respect to the target vehicle 10 will be described. The posture of the surrounding vehicles in the coordinate system with respect to the target vehicle 10 can be specified from, for example, the detection result of the sensor 12. Specifically, the posture of the peripheral vehicle 20 can be specified by matching the above-mentioned point cloud data obtained for the peripheral vehicle 20 with the shape of the peripheral vehicle 20.

However, if the point cloud data does not contain a sufficient number of data (for example, if only one location of the peripheral vehicle 20 is detected by the sensor 12), the point cloud data and the shape of the peripheral vehicle 20 may be matched. , The posture of the peripheral vehicle 20 may not be specified. In this case, for example, the estimation position calculation unit 206 uses the posture of the target vehicle 10 and the posture of the peripheral vehicle 20 on the environmental map, and sets the posture of the peripheral vehicle 20 on the environmental map as a coordinate system based on the target vehicle 10. It is converted into the posture of the peripheral vehicle 20 in. The method of acquiring the postures of the target vehicle 10 and the peripheral vehicles 20 on the environmental map is as described above.

<How to decide what to treat as a target landmark>
Those treated as target landmarks by the estimated position calculation unit 206 include 1) landmarks that can be directly detected by the sensor 12, 2) peripheral vehicles 20, and 3) landmarks 30 that are detected by the peripheral vehicles 20. Here, it is assumed that at least n (n is a positive integer) target landmarks are required for one update of the estimated position of the target vehicle 10. In this case, when the number of landmarks that can be directly detected by the sensor 12 is less than n, the estimated position calculation unit 206 treats the peripheral vehicle 20 or the landmark 30 detected by the peripheral vehicle 20 as the target landmark. At this time, the position estimation device 200 may be configured in advance so that only one of the landmark 30 and the peripheral vehicle 20 is treated as the target landmark, and which of these is treated as the target landmark depending on the situation. May be configured to determine.

In the latter case, for example, the estimation position calculation unit 206 treats the peripheral vehicle 20 as a target landmark in preference to the landmark 30 detected by the peripheral vehicle 20. The specific method will be described in the second embodiment described later.

<Case where there are multiple peripheral vehicles 20>
The estimated position calculation unit 206 uses (1) vehicle position information acquired from the peripheral vehicle 20 and (2) the relative position of the peripheral vehicle 20 with reference to the target vehicle 10 identified by using the sensor 12. The estimated position of the target vehicle 10 is calculated. Here, when there are a plurality of peripheral vehicles 20, the estimated position calculation unit 206 associates the vehicle position information acquired from each peripheral vehicle 20 with the relative position of each peripheral vehicle 20 based on the target vehicle 10. Need to be done. In other words, the estimated position calculation unit 206 needs to associate the vehicle position information with the peripheral vehicle 20 detected by the sensor 12.

FIG. 15 is a diagram illustrating the correspondence between the vehicle position information of each peripheral vehicle 20 and the relative position of each peripheral vehicle 20 with respect to the target vehicle 10. In FIG. 15, there are three peripheral vehicles 20 around the target vehicle 10, a peripheral vehicle 20-1, a peripheral vehicle 20-2, and a peripheral vehicle 20-3.

In FIG. 15, the relative positions (relative positions with respect to the target vehicle 10) of the peripheral vehicle 20-1, the peripheral vehicle 20-2, and the peripheral vehicle 20-3 identified by using the sensor 12 are Z1, respectively. Z2 and Z3. Further, the position estimation device 200 has acquired three vehicle position information: vehicle position information 40-A, vehicle position information 40-B, and vehicle position information 40-C. In this case, the estimated position calculation unit 206 identifies whether each of the vehicle position information 40-A to the vehicle position information 40-C is provided by any of the peripheral vehicle 20-1 to the peripheral vehicle 20-3. .. In other words, the estimated position calculation unit 206 matches the vehicle position information 40-C from the vehicle position information 40-A with the peripheral vehicles 20-3 to the peripheral vehicles 20-3 detected by the sensor 12.

In order to perform the matching, for example, the acquisition unit 202 acquires the vehicle position information and the feature information representing the features of the peripheral vehicle 20 from the peripheral vehicle 20. The feature information indicates, for example, one or more of the size, color, shape, and vehicle type of the peripheral vehicle 20.

Hereinafter, a method of performing the above matching using the feature information will be specifically illustrated.

<< Method 1 >>
For example, the matching is performed using the measurement result by the sensor 12 and the feature information of each peripheral vehicle 20. Specifically, the estimation position calculation unit 206 specifies the sizes of various parts such as the front surface, the back surface, and the side surface of each peripheral vehicle 20 by using the measurement result by the sensor 12. Then, the estimated position calculation unit 206 matches the vehicle position information and the sensor 12 by matching the size of the peripheral vehicle 20 indicated by each feature information with the size of each peripheral vehicle 20 specified by using the sensor 12. Matches with the peripheral vehicle 20 detected by.

FIG. 16 is a diagram illustrating a state in which the size of the peripheral vehicle 20 is specified by the sensor 12. The sensor 12 of FIG. 16 measures the distance to an object in various directions around it by outputting the measurement light while rotating. In the peripheral vehicles 20-1 to 20-3 of FIG. 16, the solid line portion represents the portion exposed to the measurement light, and the dotted line portion represents the portion not exposed to the measurement light. Therefore, the sensor 12 can specify the size of the solid line portion from the peripheral vehicle 20-1 to the peripheral vehicle 20-3. Therefore, the estimation position calculation unit 206 matches the size of each peripheral vehicle 20 shown in the feature information with the size of the solid line portion of each peripheral vehicle 20 specified by using the sensor 12, thereby obtaining the vehicle position information. Matches with the peripheral vehicle 20 detected by the sensor 12.

The estimated position calculation unit 206 may specify the shape of the peripheral vehicle 20 by using the sizes of various parts of the peripheral vehicle 20 specified based on the measurement result by the sensor 12. In this case, the estimated position calculation unit 206 matches the vehicle position information and the sensor by matching the shape of the peripheral vehicle 20 indicated by each feature information with the shape of each peripheral vehicle 20 specified by using the sensor 12. Matches with the peripheral vehicle 20 detected by 12.

<< Method 2 >>
For example, the matching between the vehicle position information and the peripheral vehicle 20 detected by the sensor 12 is performed by using the imaging result by the camera provided on the target vehicle 10 and the feature information of each peripheral vehicle 20. Specifically, the estimation position calculation unit 206 detects the peripheral vehicle 20 having the feature shown in the feature information from the captured image generated by the camera. Further, the estimation position calculation unit 206 specifies the direction in which the peripheral vehicle 20 is located based on the position of the peripheral vehicle 20 in the captured image and the angle of view of the camera when the captured image is generated. Then, the estimation position calculation unit 206 uses this specified direction to identify which of the plurality of peripheral vehicles 20 detected by the sensor 12 is the peripheral vehicle 20 detected from the captured image. By doing so, the specified peripheral vehicle 20 is associated with the vehicle position information acquired together with the feature information.

[Embodiment 2]
The functional configuration of the position estimation device 200 of the second embodiment is represented by FIG. 6 in the same manner as the functional configuration of the position estimation device 200 of the first embodiment. Except for the matters described below, the position estimation device 200 of the second embodiment has the same function as the position estimation device 200 of the first embodiment.

The acquisition unit 202 of the second embodiment further acquires accuracy information from the peripheral vehicle 20. The accuracy information of a certain peripheral vehicle 20 indicates an accuracy index value indicating the accuracy of the vehicle position information acquired from the peripheral vehicle 20. The estimated position calculation unit 206 of the second embodiment calculates the estimated position of the target vehicle 10 using this accuracy index value.

There are various ways to use the accuracy index value. For example, the estimated position calculation unit 206 uses the vehicle position information acquired from the peripheral vehicle 20 to calculate the estimated position of the target vehicle 10 based on the magnitude of the accuracy index value shown in the accuracy information acquired from the peripheral vehicle 20. Decide whether or not to do it (hereinafter, usage method 1). In addition, for example, the estimation position calculation unit 206 corrects the accuracy of the sensor 12 by using the accuracy index value shown in the accuracy information (hereinafter, usage method 2). Hereinafter, the above-mentioned two usage methods will be specifically described.

<Usage 1>
The estimated position calculation unit 206 uses the vehicle position information acquired from the peripheral vehicle 20 to calculate the estimated position of the target vehicle 10 based on the magnitude of the accuracy index value shown in the accuracy information acquired from the peripheral vehicle 20. Decide whether or not. For example, when the accuracy index value shown in the accuracy information acquired from a certain peripheral vehicle 20 is equal to or higher than a predetermined value, the estimated position calculation unit 206 uses the vehicle position information acquired from the peripheral vehicle 20. On the other hand, when the accuracy index value shown in the accuracy information acquired from the peripheral vehicle 20 is less than a predetermined value, the estimated position calculation unit 206 does not use the vehicle position information acquired from the peripheral vehicle 20.

By doing so, only the vehicle position information with a certain degree of accuracy is used for calculating the estimated position of the target vehicle 10, and the vehicle position information with low accuracy is not used for calculating the estimated position of the target vehicle 10. Therefore, it is possible to prevent the estimation accuracy of the position of the target vehicle 10 from being lowered.

<Usage method 2>
Generally, the measurement result of the sensor includes an error. Therefore, the accuracy of the sensor is used in order to improve the accuracy of the process of updating the estimated position of the vehicle based on the detection result by the sensor (the second update process described above). For example, in the mathematical formula (1), the accuracy of the sensor is used in the calculation of the likelihood P (Z1, ..., Zn | A) of the estimated position A of the target vehicle 10.

c は、第２の更新処理でセンサ１２の確度として利用する値（補正後のセンサ１２の確度）である。ci は確度指標値である。cs は、予め定められているセンサ１２の確度である。 Therefore, the estimation position calculation unit 206 corrects the accuracy of the sensor used in this second update process with the accuracy index value shown in the accuracy information. For example, the estimation position calculation unit 206 sets the accuracy of the sensor 12 used in the second update process to a value calculated by the following mathematical formula (2).

c is a value (accuracy of the sensor 12 after correction) used as the accuracy of the sensor 12 in the second update process. ci is the accuracy index value. cs is a predetermined accuracy of the sensor 12.

In this way, the accuracy of the estimated position of the target vehicle 10 can be improved by calculating the estimated position of the elephant vehicle 10 by reflecting the accuracy of the vehicle position information in the accuracy of the sensor 12.

<How to decide what to treat as a target landmark>
As described above, for example, the position estimation device 200 treats the peripheral vehicle 20 as a target landmark in preference to the landmark 30 detected by the peripheral vehicle 20. As a specific method, for example, there is a method of using the accuracy information described above. Hereinafter, a specific description will be given with reference to FIG.

FIG. 17 is a flowchart illustrating a flow of processing for determining what is to be treated as a target landmark. Here, it is preferable that m or more target landmarks can be obtained for calculating the estimated position of the target vehicle 10. The vehicle information shows the estimated position and posture of the peripheral vehicle 20 on the environmental map, the absolute position of the landmark 30 on the environmental map, the relative position of the landmark 30 with respect to the peripheral vehicle 20, and the accuracy information. There is. Further, the accuracy information includes a first accuracy index value indicating the accuracy of the estimated position of the peripheral vehicle 20 on the environmental map, and a second accuracy index value indicating the accuracy of the relative position of the landmark 30 with respect to the peripheral vehicle 20. It is shown.

First, the estimation position calculation unit 206 includes each landmark that can be directly detected by the sensor 12 in the target landmark (S302). The estimation position calculation unit 206 determines whether or not m or more target landmarks have been obtained (S304). When m or more target landmarks are obtained (S304: YES), the process of FIG. 17 ends. On the other hand, when m or more target landmarks have not been obtained (S304: NO), the estimated position calculation unit 206 includes each peripheral vehicle 20 having a first accuracy index value of a predetermined value or more in the target landmarks (S304: NO). S306).

The estimation position calculation unit 206 determines whether or not m or more target landmarks have been obtained (S308). When m or more target landmarks are obtained (S308: YES), the process of FIG. 17 ends. On the other hand, when m or more target landmarks are not obtained (S308: NO), the position estimation device 200 has a second accuracy index value of a predetermined value or more among the landmarks 30 detected by the peripheral vehicles 20. The thing is included in the target landmark (S310).

According to the above flow, it is treated as a target landmark in the order of priority of 1) a landmark that can be directly detected by the sensor 12, 2) a peripheral vehicle 20 with high accuracy, and 3) a landmark 30 that is detected by the peripheral vehicle 20. Things are decided.

When the number of target landmarks finally obtained in the flowchart of FIG. 17 is less than m, the estimated position calculation 206 uses the finally obtained target landmarks to determine the estimated position of the target vehicle 10. It may be calculated, or the estimated position of the target vehicle 10 may not be calculated.

<Example of hardware configuration>
The hardware configuration of the position estimation device 200 of the second embodiment is represented by, for example, FIG. 7, similar to the hardware configuration of the position estimation device 200 of the first embodiment. Further, in the present embodiment, the program module stored in the storage device 108 described above further includes a program that realizes the functions described in the present embodiment.

Although the embodiments of the present invention have been described above with reference to the drawings, these are examples of the present invention, and combinations of the above embodiments or various configurations other than the above can be adopted.
Hereinafter, an example of the reference form will be added.
1. 1.
An acquisition means for acquiring vehicle position information, which is information on the position of the second vehicle, from a second vehicle existing around the first vehicle, and
A relative position specifying means for calculating the relative position of the second vehicle with respect to the first vehicle using the measured value of the sensor provided on the first vehicle, and
A position having an estimated position calculating means for calculating an estimated position of the first vehicle by using the vehicle position information acquired from the second vehicle and the relative position of the second vehicle with respect to the first vehicle. Estimator.
2.
The vehicle position information indicates an estimated position of the second vehicle.
The estimated position calculation means calculates the estimated position of the first vehicle using the estimated position of the second vehicle. The position estimation device described in 1.
3. 3.
The vehicle position information indicates the position of a landmark measured by a sensor provided in the second vehicle.
The estimated position calculation means calculates the estimated position of the first vehicle using the position of the landmark. The position estimation device described in 1.
4.
The estimated position calculation means determines whether or not a landmark can be detected by the sensor, and if the landmark cannot be detected, the vehicle position information acquired from the second vehicle and the first vehicle are used as a reference. 1. Calculate the estimated position of the first vehicle using the relative position of the second vehicle. ~ 3. The position estimation device according to any one.
5.
The acquisition means acquires an accuracy index value indicating the accuracy of the information indicated by the vehicle position information from the second vehicle.
The estimated position calculation means calculates the estimated position of the first vehicle using the accuracy index value. ~ 4. The position estimation device according to any one.
6.
5. The estimated position calculation means uses the vehicle position information acquired from the second vehicle when the accuracy index value acquired from the second vehicle is equal to or greater than a predetermined value. The position estimation device described in 1.
7.
The vehicle position information indicates the estimated position of the second vehicle, the position of the landmark measured by the sensor provided on the second vehicle, and the accuracy index value.
The accuracy index value includes a first accuracy index value representing the accuracy of the estimated position of the second vehicle and a second accuracy index value representing the accuracy of the position of the landmark.
The estimated position calculation means
When the first accuracy index value is equal to or higher than a predetermined value, the estimated position of the first vehicle is calculated using the estimated position of the second vehicle.
When the first accuracy index value is less than the predetermined value and the second accuracy index value is equal to or more than the predetermined value, the estimated position of the first vehicle is calculated using the position of the landmark. .. The position estimation device described in 1.
8.
The acquisition means acquires feature information representing the features of the second vehicle from each of the plurality of second vehicles.
The estimated position calculation means uses the feature information acquired from the second vehicle, and the vehicle position information acquired from the second vehicle is based on the first vehicle calculated for each of the plurality of the second vehicles. 1. Correspond to one of the relative positions. ~ 7. The position estimation device according to any one.
9.
The feature information indicates the size or shape of the second vehicle.
The estimated position calculation means specifies the size or shape of the second vehicle based on the measurement result of the sensor, specifies the feature information representing the specified size, and specifies the second vehicle. 8. Correspond the relative position with respect to the first vehicle to the vehicle position information provided by the second vehicle that provided the feature information. The position estimation device described in 1.
10.
The feature information indicates any one or more of the size, color, and shape of the second vehicle.
The first vehicle is provided with a camera that captures the second vehicle and generates an captured image.
The estimated position calculation means uses the captured image and the feature information to identify the direction from the first vehicle toward the second vehicle that provided the feature information.
The association between the feature information and the relative position is determined based on the relative position and the direction with respect to the first vehicle specified for each of the second vehicles, and the association is determined by the determined association. 8. Determine the correspondence between the vehicle position information and its relative position. The position estimation device described in 1.
11.
It is a control method executed by a computer.
An acquisition step of acquiring vehicle position information, which is information on the position of the second vehicle, from a second vehicle existing around the first vehicle, and
A relative position specifying step of calculating the relative position of the second vehicle with respect to the first vehicle using the measured values of the sensors provided on the first vehicle, and
A control having a vehicle position calculation step of calculating an estimated position of the first vehicle using the vehicle position information acquired from the second vehicle and the relative position of the second vehicle with respect to the first vehicle. Method.
12.
11. A program that causes a computer to perform each step of the control method described in.

10 Target vehicle 20 Peripheral vehicle 30 Landmark 100 Computer 102 Bus 104 Processor 106 Memory 108 Storage device 110 Input / output interface 112 Network interface 200 Position estimation device 202 Acquisition unit 204 Relative position identification unit 206 Estimated position calculation unit

Claims (11)

An acquisition means for acquiring vehicle position information, which is information on the position of the second vehicle, from a second vehicle existing around the first vehicle, and
A relative position specifying means for calculating the relative position of the second vehicle with respect to the first vehicle using the measured value of the sensor provided on the first vehicle, and
The acquired vehicle position information from the second vehicle, and using the relative position of the second vehicle relative to the first vehicle, have a, and estimated position calculating means for calculating the estimated position of the first vehicle ,
The vehicle position information indicates a relative position of a landmark with respect to the second vehicle, which is measured by a sensor provided in the second vehicle.
The estimated position calculation means
Using the relative position of the landmark based on the second vehicle and the relative position of the second vehicle based on the first vehicle shown in the vehicle position information, the first vehicle is used as a reference. Identify the relative position of the landmark,
A position estimation device that calculates an estimated position of the first vehicle using the relative position of the landmark with respect to the specified first vehicle. The estimated position calculation means determines whether or not a landmark can be detected by the sensor, and if the landmark cannot be detected, the vehicle position information acquired from the second vehicle and the first vehicle are used as a reference. The position estimation device according to claim 1, wherein the estimated position of the first vehicle is calculated by using the relative position of the second vehicle. The acquisition means acquires an accuracy index value indicating the accuracy of the information indicated by the vehicle position information from the second vehicle.
The position estimation device according to claim 1 or 2 , wherein the estimated position calculating means calculates an estimated position of the first vehicle using the accuracy index value. The position estimation according to claim 3 , wherein the estimated position calculation means uses the vehicle position information acquired from the second vehicle when the accuracy index value acquired from the second vehicle is equal to or higher than a predetermined value. apparatus. The acquisition means acquires feature information representing the features of the second vehicle from each of the plurality of second vehicles.
The estimated position calculation means uses the feature information acquired from the second vehicle, and the vehicle position information acquired from the second vehicle is based on the first vehicle calculated for each of the plurality of the second vehicles. The position estimation device according to any one of claims 1 to 4, which is associated with one of the relative positions. The feature information indicates the size or shape of the second vehicle.
The estimated position calculating means specifies the size or shape of the second vehicle based on the measurement result of the sensor, specifies the feature information representing the specified size, and specifies the second vehicle. The position estimation device according to claim 5 , wherein a relative position with respect to the first vehicle is associated with the vehicle position information provided by the second vehicle that provided the characteristic information. The feature information indicates any one or more of the size, color, and shape of the second vehicle.
The first vehicle is provided with a camera that captures the second vehicle and generates an captured image.
The estimated position calculation means uses the captured image and the feature information to identify the direction from the first vehicle toward the second vehicle that provided the feature information.
The association between the feature information and the relative position is determined based on the relative position and the direction with respect to the first vehicle specified for each of the second vehicles, and the association is determined by the determined association. The position estimation device according to claim 5 , wherein the association between the vehicle position information and the relative position thereof is determined. The vehicle position information includes information for identifying a landmark measured by a sensor provided in the second vehicle.
The position estimation device according to any one of claims 1 to 7, wherein the estimated position calculating means calculates an estimated position of the first vehicle by further using information for identifying the landmark. The estimated position calculation means
Using the measured values of the sensors provided on the first vehicle, the posture of the second vehicle in the coordinate system with respect to the first vehicle is specified.
The position estimation device according to any one of claims 1 to 8, further using the identified posture of the second vehicle to specify the relative position of the landmark with respect to the first vehicle. It is a control method executed by a computer.
An acquisition step of acquiring vehicle position information, which is information on the position of the second vehicle, from a second vehicle existing around the first vehicle, and
A relative position specifying step of calculating the relative position of the second vehicle with respect to the first vehicle using the measured values of the sensors provided on the first vehicle, and
The acquired vehicle position information from the second vehicle, and using the relative position of the second vehicle relative to the first vehicle, have a, and the estimated position calculation step of calculating an estimated position of the first vehicle ,
The vehicle position information indicates a relative position of a landmark with respect to the second vehicle, which is measured by a sensor provided in the second vehicle.
In the estimated position calculation step,
Using the relative position of the landmark based on the second vehicle and the relative position of the second vehicle based on the first vehicle shown in the vehicle position information, the first vehicle is used as a reference. Identify the relative position of the landmark,
A control method for calculating an estimated position of the first vehicle using the relative position of the landmark with respect to the specified first vehicle. Program for executing the steps of the control method according to the computer to claim 1 0.

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