Classifications

• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
  • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
  • G01C21/26—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for navigation in a road network
  • G01C21/28—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for navigation in a road network with correlation of data from several navigational instruments
• • G—PHYSICS
  • G08—SIGNALLING
  • G08G—TRAFFIC CONTROL SYSTEMS
  • G08G1/00—Traffic control systems for road vehicles

Definitions

• the present invention relates to a position estimation method and a position estimation system for estimating the position of a vehicle on a three-dimensional map representing a traveling environment.
• Patent Document 2 For example, in Patent Document 2 below, lane marks, curbs, guardrails, etc.
• Patent Document 1 Japanese Unexamined Patent Publication No. 2 0 1 8 _ 1 2 8 3 6 4
• Patent Document 2 JP 2 0 1 4 _ 3 4 2 5 1 Publication
• the present invention has been made in view of the above-mentioned conventional problems, and an object of the present invention is to provide a method and system for accurately estimating the position of the own vehicle in a three-dimensional map. ..
• One aspect of the present invention is a position estimation method for estimating an absolute position of a vehicle in a three-dimensional map representing a traveling environment
• the position of the marker laid on the road is specified, and the marker detection process for detecting the marker,
• a position including a relative position estimation process for estimating the relative position of the own vehicle with respect to the marker, and an absolute position estimation process for estimating the absolute position of both the own vehicle on the three-dimensional map based on the relative position of the own vehicle with respect to the marker. It is in the estimation method.
• One aspect of the present invention is a position estimation system for estimating an absolute position of a vehicle in a three-dimensional map representing a traveling environment,
• the position of the marker laid on the road is specified, and a marker detection unit that detects the marker,
• the relative position estimating unit that estimates a relative position of the vehicle relative to the Ma _ force, the absolute position estimation unit for estimating the absolute position of the vehicle both in the three-dimensional map based on the relative position of the vehicle relative to the marker, the The effect of the invention in the position estimation system including
• the present invention is based on the proposal of a three-dimensional map in which the position of a marker laid on a road is specified, and uses the marker to estimate the absolute position of the host vehicle in the three-dimensional map. Since the markers laid on the road are fixed on the driving environment side, there is almost no positional change. By using a marker whose position is fixed, it is possible to accurately estimate the absolute position of the vehicle on the 3D map.
• FIG. 1 An explanatory diagram of a position estimation system according to the first embodiment.
• FIG. 2 A block diagram showing a vehicle side system configuration in the first embodiment. ⁇ 0 2020/175439 3 ⁇ (: 171? 2020 /007364
• FIG. 3 Explanatory drawing of the magnetic marker in Example 1.
• FIG. 4 A front view of the 3 ⁇ 4 I 0 tag in the first embodiment.
• FIG. 5 Explanatory diagram illustrating the change in the magnetic measurement value in the traveling direction when passing through the magnetic marker in the first embodiment.
• FIG. 6 is an explanatory view illustrating the distribution of magnetic measurement values in the vehicle width direction by the magnetic sensors ⁇ 3 n arranged in the vehicle width direction in the first embodiment.
• FIG. 7 A flow chart illustrating the flow of a vehicle position estimation process in the first embodiment.
• FIG. 8 A flow chart showing the flow of direction estimation processing in the first embodiment.
• FIG. 9 A flowchart showing the flow of direction estimation processing in the second embodiment.
• FIG. 10 is an explanatory view showing the relationship between the lateral deviation difference ⁇ when passing two magnetic markers and the azimuth deviation angle in the second embodiment.
• FIG. 11 An explanatory view illustrating a situation in which a vehicle travels along a straight road in the second embodiment.
• FIG. 12 is an explanatory diagram illustrating a situation in which a vehicle is skewed on a straight road in the second embodiment.
• FIG. 13 is an explanatory diagram illustrating a situation in which a vehicle travels along a curved road in the second embodiment.
• FIG. 14 is an explanatory diagram illustrating a situation in which a vehicle is skewed on a curved road in the second embodiment.
• FIG. 15 In Example 3, the difference between the lateral deviations for the two magnetic markers is ⁇ !
• This example is an example of a position estimation method and a position estimation system 1 for accurately estimating the absolute position of the own vehicle in a three-dimensional map that represents the driving environment. The contents will be described with reference to FIGS. 1 to 8.
• the 3D map is represented in the global coordinate system (world coordinate system) defined by the north, south, east, and west directions. ⁇ 0 2020/175439 4 (:171?2020/007364
• the 3D map data representing this 3D map is the 3D data in the global coordinate system.
• the three-dimensional structure in front of the vehicle 5 is displayed in the oral coordinate system based on the vehicle 5.
• the 3D data representing this 3D structure is 3D data in the oral-coordinate system.
• a coordinate transformation is required to replace the 3D data in the global coordinate system with the 3D data in the oral-coordinate system and vice versa. This coordinate transformation requires that the direction of the coordinate axes of the oral-cal coordinate system in the global coordinate system be specified.
• the 3D map data of the 3D map is subjected to coordinate conversion to represent the 3D structure in front. Can be replaced with
• the position estimation system 1 of this example is a system for estimating the absolute position of the own vehicle (referred to as the own vehicle position) in the three-dimensional map.
• the position estimation system 1 is combined with, for example, an automatic driving system (not shown) for realizing automatic driving.
• the automated driving system uses the vehicle position estimated by the position estimation system 1 to recognize the three-dimensional structure of the driving environment ahead.
• the automatic driving system uses various on-board sensors to grasp the surrounding conditions and then executes vehicle control according to the three-dimensional structure in front of the vehicle to realize automatic vehicle driving.
• the position estimation system 1 includes a sensor array 21 for detecting a magnetic marker 10 as an example of a marker, and an MU (Inertia I Measurement Un it) 2 for inertial navigation. 2, camera 3 5 for shooting ahead, tag reader 3 4 for reading unique information of magnetic marker 10, map database (map DB) 40 for storing 3D map data which is map data of 3D map, And a control unit 32 that executes absolute position estimation processing, etc.
• a sensor array 21 for detecting a magnetic marker 10 as an example of a marker
• an MU Inertia I Measurement Un it
• map database map database
• control unit 32 that executes absolute position estimation processing, etc.
• the measurement unit 2 in which the sensor array 21 and the M U 2 2 are integrated is illustrated.
• a magnetic marker 10 laid on a road which is an example of a traveling road, will be outlined, and then a configuration on the vehicle 5 side such as a measurement unit 2, a tag reader 34, and a control unit 3 2 will be described.
• ⁇ 02020/175439 5 (: 17 2020 /007364
• the magnetic marker 10 is a road marker laid on the road surface 1003 (Fig. 1) of the road on which the vehicle 5 travels, as shown in Fig. 3.
• the magnetic markers 10 are arranged, for example, at intervals of 10 along the center of the lane divided by the left and right lane marks.
• the magnetic marker 10 is, as shown in FIG. It has a column shape with a height of 2810.1.
• the magnetic marker 10 is laid in a state of being housed in a hole provided on the road surface 1003 (see Fig. 1).
• the magnet forming the magnetic marker 10 is a ferro-plastic magnet in which magnetic particles of iron oxide, which is a magnetic material, are dispersed in a polymer material that is a base material. This magnet has a maximum energy product (Mimi
• Table 1 shows a part of the specifications of the magnetic marker 10 of this example.
• This magnetic marker 10 exerts magnetism with a magnetic flux density of 8 /x T (microtesla) at the upper limit of 250 mm height in the range of 100 to 250 mm assumed as the mounting height of the measuring unit 2.
• an RF D tag (Radio Frequency Identification, radio tag) 15 that outputs information wirelessly is attached to the upper end surface. ..
• the RF F D tag 15 operates by external power feeding by radio and transmits a marker D (identification information), which is an example of unique information of the magnetic marker 10.
• the magnet used in the magnetic marker 10 of this example is a magnet in which magnetic particles of iron oxide are dispersed in a polymer material. This magnet has low conductivity, and eddy currents, etc. are unlikely to occur during wireless power feeding. Therefore, the RF D tag 15 attached to the magnetic marker 10 can efficiently receive the electric power wirelessly transmitted. ⁇ 0 2020/175439 6 ⁇ (: 171-1? 2020/007364
• the RF ⁇ D tag 15 which is an example of the information providing unit is, for example, a C chip 157 on the surface of a tag sheet 150 (Fig. 4) cut out from PET (Polyethy len terephtha late) film. Is an electronic component mounted. On the surface of the tag sheet 150, printed patterns of the loop coil 151 and the antenna 153 are provided.
• the loop coil 1 51 is a power receiving coil in which an exciting current is generated by electromagnetic induction from the outside.
• the antenna 153 is a transmission antenna for wirelessly transmitting position data and the like.
• the vehicle 5 is equipped with (1) measurement unit 2, (2) tag reader 34, (a)
• the measurement unit 2 (Fig. 2) is a unit that integrates the sensor array 21 and the MU (Inertial Measurement Unit) 2 2.
• the sensor array 21 serves as an example of a marker detection unit, and also functions as a lateral displacement amount measurement unit and a relative position estimation unit.
• ⁇ M U 22 is an example of the relative position estimation unit.
• This rod-shaped measuring unit 2 which is long in the vehicle width direction, is mounted inside the front bumper of the vehicle 5, facing the road surface 100 S (see Fig. 1). In the case of the vehicle 5 of this example, the mounting height of the measurement unit 2 based on the road surface 100 S is 200 mm.
• the sensor array 2 1 (Fig. 2) of the measurement unit 2 includes 15 magnetic sensors C n (n is an integer of 1 to 15) arranged in a straight line along the vehicle width direction, A detection processing circuit 2 1 2 including a CPU (not shown) and the like are provided.
• 15 magnetic sensors C n are arranged at regular intervals of 1 O cm.
• the magnetic sensor C n is a sensor that detects magnetism by utilizing a known MI effect (Magnet Impedance Effect) that the impedance of a magnetic sensitive body such as an amorphous wire sensitively changes according to an external magnetic field.
• MI effect Magnetic Impedance Effect
• magnetic sensitive elements such as amorphous wires (not shown) are arranged along the two orthogonal axes. ⁇ 02020/175439 7 ⁇ (: 171-1? 2020 /007364
• the magnetic sensor ⁇ 3 can detect magnetism acting in two orthogonal axes.
• the magnetic sensor ⁇ is incorporated in the sensor array 21 so that the magnetic components in the traveling direction and the vehicle width direction can be detected.
• the magnetic sensor ⁇ is a high-sensitivity sensor with a magnetic flux density measuring range of ⁇ 0.601 and magnetic flux resolution within the measuring range of 0.02.
• the frequency of the magnetic measurement by each magnetic sensor ⁇ of the measurement unit 2 is set so that the vehicle 5 can run at high speed.
• Table 2 shows a part of the specifications of the magnetic sensor ( 3 n.
• the magnetic marker 10 can act on magnetism having a magnetic flux density of 8 MT or more in the range of 100 to 250 mm that is considered as the mounting height of the magnetic sensor C n. With a magnetic marker 10 that exerts magnetism with a magnetic flux density of 8 MT or more, it is possible to detect with high certainty using a magnetic sensor C n with a magnetic flux resolution of 0.02 MT.
• the detection processing circuit 2 12 (FIG. 2) of the sensor array 21 is an arithmetic circuit that executes marker detection processing for detecting the magnetic marker 10.
• This detection processing circuit 2 1 2 is configured by using a CPU (central processing unit) that executes various operations, as well as memory elements such as ROM (read only memory) and RAM (random access memory). ..
• the detection processing circuit 2 1 1 2 acquires a sensor signal output from the magnetic sensor C n at a frequency of 3 kHz and executes marker detection processing. Then, the detection processing circuit 2 12 inputs the detection result of the marker detection processing to the control unit 32. As will be described in detail later, in this marker detection processing, in addition to the detection of the magnetic marker 10, the lateral deviation amount of the vehicle 5 with respect to the detected magnetic marker 10 is measured. Detection ⁇ 0 2020/175 439 8 ⁇ (: 171? 2020 /007364
• the logic circuit 2 12 has a function as a measurement unit that measures the amount of lateral displacement of the vehicle with respect to the magnetic marker 10.
• the IV! II 22 installed in the measurement unit 2 is an inertial navigation unit that executes a process of estimating the movement of the vehicle 5 by inertial navigation.
• the 2 2 is equipped with a 2-axis magnetic sensor 2 21 that is an electronic compass that measures azimuth, a 2-axis acceleration sensor 2 2 2 that measures acceleration, and a 2-axis gyro sensor 2 2 3 that measures angular velocity.
• a motion estimator that estimates the motion of your vehicle 2 2 uses the measured values of acceleration, angular velocity, bearing, etc., and estimates the relative position after movement (after exercise) with the specific position where vehicle 5 was located in the past as the starting point (reference)
• [0030] 2 calculates the momentary displacement amount by the second-order integration of acceleration, and at the same time, calculates the momentary direction of the vehicle 5 with high accuracy by using the direction change amount, which is the integral of angular velocity, and the measured direction. To do. Then, 1//1112 2 calculates the relative position with respect to the reference position by integrating the displacement amount along the direction of the vehicle 5. If the relative position estimated by I
• the tag reader 34 which is an example of the unique information reading unit, is a communication unit that wirelessly communicates with the I 0 tag 15 (Fig. 3) attached to and held by the magnetic marker 10.
• Tag reader 34 The power required to operate the I 0 tag 15 is transmitted wirelessly, I 0 Receives marker I 0 (unique information) transmitted by tag 15 (unique information reading process).
• the control unit 32 is a unit that controls the measurement unit 2 and the tag reader 34, and has a function as a position estimation unit (relative position estimation unit, absolute position estimation unit) that estimates the vehicle position. ..
• the control unit 32 includes an electronic board (not shown) on which memory devices such as II, [3 ⁇ 4 IV! and 8 IV!, etc., which execute various operations are mounted. Control as a position estimation unit will be described in detail later. ⁇ 0 2020/175 439 9 (:171? 2020/007364
• the unit 3 2 uses the relative position of the own vehicle with respect to the magnetic marker 10 (relative position estimation processing) to estimate the own vehicle position which is the absolute position of the own vehicle in the 3D map (absolute position estimation processing). ).
• the 3D map is a 3D map in which spatial information in the height direction is added to the 2D map in which the structure of roads and areas of buildings are specified. Furthermore, in the three-dimensional map adopted by the position estimation system 1 of this example, the laying positions of the magnetic markers 10 arranged along the lane are specified.
• the spatial information included in the three-dimensional map includes the height of the curb beside the road, the height of the guardrail, and the spatial position of the signboard overhanging the lane. ..
• the 3D map also includes lane mark information that indicates the position of the lane marks (white lines) that separate lanes.
• attribute information is attached to the features that make up the driving environment. For example, in addition to height information, curbstones in a 3D map are associated with attribute information indicating that they are curbs.
• Each magnetic marker 10 in the three-dimensional map is associated with attribute information indicating that it is a magnetic marker 10, unique information such as the marker mouth, and position information indicating the position on the three-dimensional map. There is.
• the marker detection process is a process executed by the sensor array 2 1 (detection processing circuit 2 1 2) of the measurement unit 2.
• the sensor array 2 1 uses the magnetic sensor Executes marker detection processing at frequency 2.
• the magnetic sensor ⁇ 3 n can measure the magnetic components in the traveling direction and the vehicle width direction of the vehicle 5. For example, when this magnetic sensor ⁇ 3 n moves in the traveling direction and passes directly above the magnetic marker 10, the magnetic measurement value in the traveling direction is inverted between positive and negative before and after the magnetic marker 10 as shown in Fig. 5. And above the magnetic marker 10 ⁇ 0 2020/175 439 10 (:171? 2020/007364
• the measurement unit 2 is placed directly above the magnetic marker 1 0 when a zero-cross 0 in which the sign of the magnetic field in the traveling direction detected by one of the magnetic sensors 0 n is reversed. You can judge that it is located.
• the detection processing circuit 2 1 2 detects the magnetic marker 1 0 when the measurement unit 2 is located directly above the magnetic marker 10 and a zero cross of the magnetic measurement value in the traveling direction occurs as described above. To judge.
• a magnetic measurement in the vehicle width direction is performed.
• the value changes such that the positive and negative values are inverted on both sides of the magnetic marker 10 and that the value crosses zero at a position directly above the magnetic marker 10.
• the magnetic sensor 0 depends on which side through the magnetic marker 10 as shown in the example in Fig. 6. The positive/negative of the magnetism in the vehicle width direction that is detected by.
• Each magnetic sensor of the measurement unit 2 (a diagram illustrating magnetic measurement values in the vehicle width direction of 3 n )
• the position of the magnetic marker 10 in the vehicle width direction by using the zero-cross 0 in which the positive/negative of the magnetism in the vehicle width direction is reversed.
• the zero cross ⁇ is located in the middle of the two adjacent magnetic sensors ⁇ (not necessarily in the center)
• the middle position of the two magnetic sensors ⁇ adjacent to each other across the zero cross ⁇ is the magnetic marker 1 0.
• the zero cross ⁇ coincides with the position of one of the magnetic sensors ⁇ , that is, the magnetic measurement value in the vehicle width direction is zero and the positive and negative of the magnetic measurement values of the adjacent magnetic sensors ⁇ 3 n are reversed. If there is a magnetic sensor ⁇ n present, the position directly below the magnetic sensor ⁇ is the position of the magnetic marker 10 in the vehicle width direction.
• the detection processing circuit 2 1 2 which is an example of the relative position estimation unit detects the deviation of the position of the magnetic marker 10 in the vehicle width direction from the center position of the measurement unit 2 (position of the magnetic sensor 08). Is measured as the lateral deviation amount of the vehicle 5 with respect to the magnetic marker 10 (processing for measuring the lateral deviation amount).
• the position of the zero cross ⁇ is the position corresponding to ⁇ 9.5, which is the middle of ⁇ 9 and ⁇ 10. ⁇ 0 2020/175439 1 1 ⁇ (: 171? 2020 /007364
• the process of measuring the lateral shift amount with respect to the magnetic marker 10 is an example of the first relative position estimation process by the relative position estimation unit.
• the own vehicle position estimation process is a process of estimating the own vehicle position (absolute position of the own vehicle) on the three-dimensional map.
• the process flow in Fig. 7 includes the direction estimation process for estimating the direction of the own vehicle on the 3D map, and the process for calculating the 3D structure of the own vehicle reference. ing. The contents of these processes will be described below with reference to FIG.
• the control unit 32 repeatedly executes the vehicle position estimation process of FIG. 7 while the vehicle 5 is traveling.
• the control unit 32 first controls the measurement unit 2 to execute the marker detection processing 1.
• the control unit 3 2 measures from the measuring unit 2 the amount of lateral deviation, which is the relative position of the host vehicle with respect to the magnetic marker 10. Get (3 1 0 2).
• the control unit 32 controls the tag reader 34 to execute the tag reading process 2, and acquires and records the marker mouth which is the unique information of the magnetic marker 10.
• the marker mouth acquired and recorded by executing this tag reading process 2 is rewritten when a new marker mouth is acquired in response to the detection of the new magnetic marker 10.
• the control unit 3 2 uses the position of the vehicle when the magnetic marker was detected last time as a reference.
• the relative position estimated by 2 2 is used to execute the process of estimating the relative position of the host vehicle using the magnetic marker as a reference (3 1 1 2, an example of the second relative position estimation process).
• control unit 32 is based on the lateral deviation amount measured when the previous magnetic marker was detected, and the relative position estimated by ⁇ 22, which is the previously detected magnetic marker. Estimate the relative position of the vehicle with respect to. Previously detected ⁇ 0 2020/175439 12 ⁇ (: 171? 2020 /007364
• the relative position of the vehicle based on the magnetic marker is based on the vehicle width direction vector corresponding to the amount of lateral deviation when the previous magnetic marker was detected and the vehicle position when the previous magnetic marker was detected.
• control unit 32 generates marker reference data including the marker I 0 and the data of the relative position with respect to the magnetic marker 10 (3 10 3).
• the marker I 0 recorded according to the most recent execution of the tag reading process 2 is adopted.
• the lateral shift amount in step 3102 above or the relative position estimated in step 1112 above becomes the data of the relative position to be included in the marker reference data.
• the control unit 32 refers to the map 0 40 by using the marker entrance included in the marker reference data, and specifies the magnetic marker 10 associated with the marker reference data (3 10 4). .. Then, the control unit 32 uses the relative position data included in the marker reference data and estimates the own vehicle position (absolute position of the own vehicle) with reference to the laid position (absolute position) of the magnetic marker 10. Yes (3 105, _Example of absolute position estimation processing).
• control unit 32 estimates the heading of the vehicle 5 by executing heading estimation processing 3 (described later with reference to FIG. 8 ). Then, the control unit 32 calculates a three-dimensional structure with the own vehicle as a reference based on the estimated direction of the vehicle 5 (3106). Specifically, the coordinate transformation is applied to the three-dimensional information (three-dimensional data) of the surrounding three-dimensional ground map read from the map 0 to 40, and the three-dimensional structure is calculated based on the vehicle. To do.
• the three-dimensional structure based on the host vehicle serves as useful information for automatically driving the vehicle 5.
• the above-mentioned azimuth estimation process 3 (Fig. 8) is a process of estimating the vehicle azimuth (absolute azimuth of the vehicle) on the three-dimensional map.
• This azimuth estimation process 3 is an example of the absolute azimuth estimation process executed by the control unit 32 in the vehicle position estimation process of Fig. 7.
• the control unit 32 When executing the direction estimation processing 3, the control unit 32 ⁇ 0 2020/175439 13 ⁇ (: 171? 2020 /007364
• the lane mark that divides the lane of the vehicle is detected from the front image (3301).
• the control unit 32 calculates a three-dimensional data indicating the three-dimensional position of the detected lane mark based on the optical specifications (optical axis direction, angle of view, etc.) of the camera 35. (3 302).
• the 30 data of this lane mark is the 30 data derived from the image taken by the camera 35, and is the 30 data of the aforementioned oral-coordinate system centered on the vehicle 5 side including the camera 35.
• 30-day data in the oral-coordinate system is called oral-calda 3 data.
• control unit 32 displays a three-dimensional map with reference to the map mouth 40.
• the 30 data of this lane mark is the 30 data of the global coordinate system that defines the 3D map.
• 30 data in the global coordinate system will be referred to as global 3 data.
• the control unit 32 examines what kind of coordinate conversion can be performed on the global 30 data of the lane mark to convert it to the oral 30 data calculated in step 3302 above. .. Specifically, the control unit 32 is an absolute azimuth in a three-dimensional map expressed in the glow/rule coordinate system, and is an azimuth in which the global 3D data of the lane mark can be coordinate-converted into the oral 3D data. Calculate by calculation. This absolute direction is the vehicle direction on the 3D map. In this way, the control unit 32 of this example uses the lane marks to estimate the vehicle direction on the three-dimensional map (3304, absolute direction estimation processing).
• the position estimation system 1 of this example uses the magnetic marker 10
• the vehicle position on the 3D map is estimated, and the vehicle direction on the 3D map is estimated using the lane mark in the front image. If the vehicle position and the vehicle direction on the 3D map are known, the 3D structure in front of the vehicle 5 can be calculated, and control such as automatic driving becomes possible.
• the position estimation system 1 is a system based on a three-dimensional map including the position information of the magnetic marker 10 laid on the traveling road. This position estimation sys ⁇ 0 2020/175439 14 ⁇ (: 171? 2020 /007364
• System 1 uses a magnetic marker 10 to realize the estimation of the absolute position of the vehicle on a 3D map.
• the magnetic marker 10 laid on the road is almost fixed because it is fixed on the road surface. If the magnetic force 10 whose position is fixed is used, the absolute position of the vehicle on the 3D map can be estimated with high accuracy. Since the position estimation system 1 in this example does not assume that ⁇ 3 radio waves are received, it is possible to estimate the position accuracy even in places where ⁇ 3 radio waves cannot be received or are unstable, such as tunnels and valleys of buildings. Does not become unstable.
• a configuration in which a magnetic tag 10 is attached to all magnetic markers 10 is illustrated.
• some magnetic markers 10 may be provided with [3 ⁇ 4 ⁇ 0 tags 15].
• a communication unit such as a radio wave beacon or an infrared line beacon installed on the roadside may be adopted.
• a vehicle compatible with a radio beacon or the like may be installed.
• an automatic driving system is illustrated as a system to be combined with the position estimation system 1.
• a departure warning system that warns of departure from the lane
• a lane keeping system that generates steering assist power to automatically steer the steering wheel along the lane or avoid departure from the lane It is also good to apply.
• the server device may have a function as the map 0 40.
• the vehicle 5 may send information necessary for estimating the position of the vehicle to the server device. Forward image ⁇ 0 2020/175 439 15 ⁇ (: 171? 2020 /007364
• the server device may also have a function of processing.
• a sensor for measuring the acceleration of the vehicle or the like may be provided on the vehicle side, while the server device that acquires the sensor output may calculate the relative position.
• the marker mouth is illustrated as the unique information of the magnetic marker 10.
• position information indicating the laid position of the magnetic marker 10 may be adopted as the unique information.
• the magnetic marker 10 is exemplified as the marker, it can be replaced with various markers arranged on the road.
• it may be a marker printed on the road surface 103 or a marker such as a cat's eye.
• the lane mark detected by the image processing is used in associating the oral-three-dimensional data with the global three-dimensional data for estimating the vehicle heading.
• the traffic lights and signs detected by laser radar, millimeter wave radar, etc. it is also possible to use the traffic lights and signs detected by laser radar, millimeter wave radar, etc., to associate the oral 3-global data with the global 3-lo data.
• This example is an example of the position estimation system 1 in which the content of the direction estimation process is changed based on the position estimation system of the first embodiment. This content will be described with reference to FIGS. 9 to 14.
• the relative azimuth of the vehicle 5 is estimated using the two magnetic markers 10.
• the magnetic markers 10 are arranged along the lane direction, two adjacent magnetic markers are arranged.
• the azimuth that connects 10 is approximately the same as the lane direction.
• the control unit (reference numeral 32 in Fig. 1) of the present example has a function of estimating both vehicle positions (front-rear direction, orientation of the center axis of the vehicle body) in the three-dimensional map.
• This function is a function as a relative azimuth estimation unit that estimates the relative azimuth of the own vehicle with respect to the azimuth connecting two adjacent magnetic markers 10 and the own azimuth on the 3D map. ⁇ 0 2020/175 439 16 ⁇ (: 17 2020 /007364
• the relative azimuth estimation unit estimates the azimuth connecting two adjacent magnetic markers 10, that is, the relative azimuth of the host vehicle with reference to the lane direction.
• the absolute azimuth estimation unit estimates the absolute azimuth of the own vehicle in the 3D map based on the relative azimuth of the own vehicle.
• the control unit executes the heading estimation process of FIG. 9 to estimate the relative heading of both the vehicle and the lane direction.
• This azimuth estimation process consists of the step of calculating the difference between the lateral displacements of the two magnetic markers 10 (3 3 1 1) and the direction of the line segment 1 ⁇ /1 (Fig. This is an example of a relative azimuth estimation process that includes the step (3 3 1 2) of calculating the azimuth deviation angle (Fig. 10), which is the relative azimuth of the vehicle 5 with respect to 10).
• the azimuth deviation angle which is the relative azimuth of the vehicle 5 with respect to the line segment direction IV! X, is the relative azimuth of the host vehicle with respect to the lane direction.
• Step 3 3 1 as shown in Fig. 10, when the vehicle 5 passes through the two adjacent magnetic markers 10, the amount of lateral deviation relative to the first magnetic marker 10 and the second The amount of lateral deviation of the magnetic marker 10 of 0 and the difference of 0 are calculated by the following equation. In the figure, since the positive and negative values of 0 1 and 0 2 are different, the absolute value of 0 1 exceeds the absolute value of 0 1 and 0 2 depending on the difference.
• step 3 3 1 2 the direction of the vehicle 5 with respect to the direction IV! X of the line segment connecting the positions of the two magnetic markers 10 is 0° Azimuth deviation angle, which is the deviation of the degree.)
• This azimuth deviation angle is calculated by the following formula that includes the lateral deviation difference difference O and the marker span 3. ⁇ 0 2020/175439 17 ⁇ (: 171? 2020/007364
• the vehicle 5 when the vehicle 5 is traveling along a straight road, the vehicle 5 is oriented in the lane direction (Fig. 11). In this case, the azimuth of the vehicle 5, which is the angle between the direction IV! X of the line segment connecting the positions of the two magnetic markers 10 and the direction of the vehicle 5, is close to zero. If the direction is not along the lane direction (Fig. 12), the direction of vehicle 5 is 0° from line segment direction IV! X, and the direction deviation angle becomes large. When the vehicle 5 is traveling along (Fig. 13), the direction IV! X of the line segment connecting the positions of the two magnetic markers 10 coincides with the tangential direction of the curved lane, and this line The direction of vehicle 5 with respect to minute direction IV! X is 0.
• the azimuth deviation angle which is the angle formed by, becomes zero.
• the deviation of the azimuth of vehicle 5 with respect to the tangential direction of a certain lane becomes large, and the azimuth deviation angle becomes large.
• the azimuth of the vehicle 5 with respect to the direction IV! X of the line segment is the angle of deviation of the vehicle, which is the relative azimuth of the host vehicle with respect to the lane direction.
• the processing it is possible to accurately estimate the relative azimuth of the vehicle with respect to the lane direction using the magnetic marker 10 (relative azimuth estimation processing).
• the magnetic marker 10 is laid on the road and its position is fixed. Therefore, it can be expected that the error in the direction connecting the two magnetic markers 10 is small, and the relative direction of the vehicle 5 based on the magnetic markers 10 is highly accurate.
• the control unit as the absolute azimuth estimating unit combines the relative azimuth of the own vehicle with respect to the lane direction and the absolute azimuth of the lane direction based on the three-dimensional map to obtain the absolute azimuth of the own vehicle on the three-dimensional map.
• Estimate Absolute direction estimation process. For example, the control unit estimates the absolute azimuths of both vehicles on the 3D map by shifting the azimuth by the relative azimuth of the vehicle based on the absolute azimuth direction on the 3D map.
• the present example is an example of the position estimation system 1 in which the content of the relative direction estimation processing for estimating the relative direction of the own vehicle with respect to the lane direction is changed based on the position estimation system of the second embodiment.
• this position estimation system 1 the relative azimuth of the host vehicle is estimated using the measurement units 2 provided in front of and behind the vehicle 5. This content will be described with reference to FIG.
• the measurement units 2 are arranged at intervals of 4.
• the distance 4 between the front and rear measurement units 2 is the distance between every two magnetic markers 10 (Marker span 3 1) is the same as _ .
• the measurement unit 2 arranged at four intervals two magnetic markers 10 adjacent to each other with one magnetic marker 10 sandwiched can be detected at substantially the same timing.
• the azimuth deviation angle can be calculated by the following equation.
• the azimuth deviation angle is the angle formed by the azimuth of the vehicle 5 with respect to the azimuth connecting the two magnetic markers 10.
• the azimuth deviation angle represents the relative azimuth of both the vehicle and the lane direction, because the azimuth that connects the two magnetic markers 10 substantially coincides with the lane direction.
• a measurement unit may be additionally arranged at the center of the measurement unit 2 before and after the four intervals. In this case, at least one of the combination of the front side measurement unit 2 and the center measurement unit, and/or the rear side measurement unit 2 and the center measurement unit, at intervals of 2 intervals. It is possible to measure the lateral deviation amount by detecting adjacent magnetic markers 10 at the same timing. Depending on the speed, it is also possible to switch between using two magnetic markers 10 with two intervals or using two magnetic markers 10 with four intervals.
• Control unit (relative position estimation unit, absolute position estimation unit, relative direction estimation unit, absolute direction estimation unit)

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• 2020
  • 2020-02-25 WO PCT/JP2020/007364 patent/WO2020175439A1/ja not_active Ceased
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