Vehicle position estimation device

Abstract

To correctly estimate a current position by suppressing degradation in position estimation accuracy of a vehicle even when a vehicle changes a lane.SOLUTION: A vehicle position estimation device comprises: a first compartment line calculation determination unit which calculates a first distance between a vehicle and a compartment line and determines the presence / absence of crossing of the compartment line by the vehicle; a second compartment line calculation determination unit which calculates a second distance between the vehicle and the compartment line and determines the presence / absence of crossing of the compartment line by the vehicle; a travel compartment matching unit which matches at least one of the first distance and the second distance on the basis of the presence / absence of crossing of the compartment line determined by the first compartment line calculation determination unit and the presence / absence of crossing of the compartment line determined by the second compartment line calculation determination unit; and a position estimation unit which estimates a position of the vehicle on the basis of the first distance or the second distance matched by the travel compartment matching unit.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present application relates to a vehicle position estimation device. [Background technology]

[0002] It is important to estimate the exact position of a vehicle while the vehicle is traveling on a road surface. Conventionally, there have been known techniques for estimating the position of a vehicle based on observation data from a plurality of detection means. Here, the detection means may be a sensor mounted on the vehicle for detecting the external environment, or a sensor provided outside the vehicle for detecting the vehicle's position, speed, and other motion parameters.

[0003] The vehicle position is calculated using a Global Navigation Satellite System (GNSS). The vehicle position is then identified on a map, and the distance to objects around the vehicle is calculated. Furthermore, the distance between the vehicle and the surrounding objects is detected using an on-board sensor. A technology has been disclosed that accurately estimates the vehicle position by minimizing the deviation between the distances calculated by these two methods (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6203982 Summary of the Invention [Problem to be solved by the invention]

[0005] The technology disclosed in Patent Document 1 is based on the premise that the surrounding objects observed by each detection means are the same object. When there are multiple objects with similar shapes and colors around the vehicle, each means may detect the distance to the vehicle for each different object. In such a case, if the vehicle position is corrected so as to minimize the deviation between the two calculated distances, the accuracy of estimating the vehicle position may deteriorate.

[0006] This problem occurs particularly when the distance to the lane markings on the road the vehicle is traveling on is used to estimate the vehicle's position. This problem becomes more pronounced when the vehicle crosses the lane markings to change lanes (driving lane), because the shapes and colors of the lane markings are similar. When the vehicle changes lanes, there is a high probability of discrepancies occurring in the "lane markings on the right and left sides of the vehicle" detected by each detection means.

[0007] The present application has been made to solve the above problems, and aims to provide a vehicle position estimation device that can suppress deterioration in the accuracy of estimating the vehicle's position and accurately estimate the current position even when the vehicle changes lanes when estimating the vehicle's position using the distance between the vehicle and a lane marking. [Means for solving the problem]

[0008] The vehicle position estimation device according to the present application comprises: a first demarcation line calculation and determination unit that detects the position of a demarcation line on a road surface, calculates a first distance between the vehicle and the demarcation line, and determines whether or not the vehicle has crossed the demarcation line based on the first distance; a second lane marking calculation and determination unit that detects a position of a lane marking on a road surface, calculates a second distance between the vehicle and the lane marking, and determines whether or not the vehicle has crossed the lane marking on the basis of the second distance; a lane matching unit that matches at least one of the first distance or the second distance based on whether or not the vehicle has crossed the lane line determined by the first lane line calculation determination unit and whether or not the vehicle has crossed the lane line determined by the second lane line calculation determination unit; and The vehicle position estimating unit is configured to estimate a position of the vehicle based on the first distance or the second distance aligned by the road segment alignment unit. Effect of the Invention

[0009] According to the vehicle position estimation device of the present application, when estimating the vehicle position using the distance between the vehicle and a lane marking, even when the vehicle changes lanes, the deterioration of the vehicle position estimation accuracy can be suppressed and the current position can be accurately estimated. [Brief description of the drawings]

[0010] [Figure 1] 1 is a configuration diagram of a vehicle position estimation device according to a first embodiment. [Diagram 2] 1 is a hardware configuration diagram of a vehicle position estimation device according to a first embodiment. [Diagram 3] FIG. 2 is a diagram showing lane changing of a vehicle according to the first embodiment. [Figure 4] 4 is a diagram showing the distance to a marking line when a vehicle changes lanes in the first embodiment. FIG. [Diagram 5] 4 is a diagram showing the distances to a marking line measured by a first sensor and a second sensor when a vehicle changes lanes in accordance with the first embodiment. FIG. [Figure 6] 5 is a diagram showing the consistency of the distances to the lane markings obtained by the first sensor and the second sensor when the vehicle changes lanes in the first embodiment. FIG. [Figure 7] 4 is a first flowchart showing the process of the vehicle position estimation device according to the first embodiment. [Figure 8] 5 is a second flowchart showing the process of the vehicle position estimation device according to the first embodiment. [Figure 9] 13 is a diagram showing the distances to a marking line measured by a first sensor and a second sensor when a vehicle changes lanes in accordance with the second embodiment. FIG. [Figure 10] 13 is a first diagram showing the consistency of the distances to the marking lines obtained by the first sensor and the second sensor when the vehicle changes lanes in the second embodiment. FIG. [Figure 11] 13 is a second diagram showing the consistency of the distances to the lane markings obtained by the first sensor and the second sensor when the vehicle changes lanes in accordance with the second embodiment. FIG. [Figure 12] 10 is a first flowchart showing the process of the vehicle position estimation device according to the second embodiment. [Figure 13]10 is a second flowchart showing the process of the vehicle position estimation device according to the second embodiment. [Figure 14] FIG. 11 is a configuration diagram of a vehicle position estimation device according to a third embodiment. [Figure 15] 11 is a first flowchart showing the process of the vehicle position estimation device according to the third embodiment. [Figure 16] FIG. 11 is a configuration diagram of a vehicle position estimation device according to a fourth embodiment. [Figure 17] 13 is a flowchart showing a process of a vehicle position estimation device according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] 1. First embodiment <Configuration of vehicle position estimation device> 1 is a configuration diagram of a vehicle position estimation device 100 according to embodiment 1. The vehicle position estimation device 100 has a first lane line calculation determination unit 101, a second lane line calculation determination unit 102, a traveling lane matching unit 113, and a position estimation unit 114. The first lane line calculation determination unit 101 is connected to a first sensor 201, and the second lane line calculation determination unit 102 is connected to a second sensor 202.

[0012] The first sensor 201 and the second sensor 202 observe the positions of the lane markings on the road surface on which the target vehicle 1 is traveling, and transmit signals related to the observed data to the first lane marking calculation determination unit 101 and the second lane marking calculation determination unit 102. The first sensor and the second sensor output observed data indicating the relative positional relationship between the target vehicle 1 and the lane markings. If there are multiple lane markings on the left or right side of the target vehicle 1, the first sensor 201 and the second sensor 202 may observe the position of each lane marking.

[0013] Here, the first sensor 201 and the second sensor 202 may be of any type as long as they have the function of acquiring the relative positional relationship between the target vehicle 1 and the lane markings. The first sensor 201 and the second sensor 202 may be a sensor device having a function of acquiring the relative positional relationship between the target vehicle 1 and the lane markings by a visible light image or an image other than visible light acquired by an imaging element. Alternatively, for example, the first sensor 201 and the second sensor 202 may be a sensor device having a function of acquiring the relative positional relationship between the target vehicle 1 and the lane markings by irradiating electromagnetic waves in a predetermined frequency band and receiving electromagnetic waves reflected from an object. Alternatively, for example, the first sensor 201 and the second sensor 202 may be a sensor having a function of acquiring the relative positional relationship between the target vehicle 1 and the lane markings by combining information on the latitude and longitude of the target vehicle 1 calculated based on a signal received from an artificial satellite, continuous relative movement information calculated by measuring the moving distance, moving speed, and acceleration of the target vehicle 1, and map information. In this case, the positional relationship between the target vehicle 1 and the lane markings calculated from information such as an artificial satellite signal, a wheel rotation sensor, an acceleration sensor, a turning acceleration sensor, and map data can be used as input information. Furthermore, the first sensor 201 and the second sensor 202 may be sensor devices of different types, or may be sensors of the same type but with different characteristics such as measurement sensitivity.

[0014] The vehicle position estimation device 100 outputs an estimated position of the target vehicle 1. Here, the estimated position of the target vehicle 1 may be specified by the relative position of the target vehicle 1 with respect to the left and right dividing lines of the lane (driving lane) in which the target vehicle 1 is traveling. In addition, a value indicating the distance to the dividing line based on the position of the target vehicle 1 can also be used as information for specifying the position of the target vehicle 1 in the lane. In the following, as an example of the estimated position of the target vehicle 1, a case will be described in which the value of the relative distance between the left and right dividing lines in a coordinate system with the target vehicle 1 as the origin is treated as the estimated position of the target vehicle 1.

[0015] The estimated position of the target vehicle 1 output by the vehicle position estimation device 100 can be used as an input to a display device and a vehicle control device. The estimated position of the target vehicle 1 at time t can be output in real time based on the observation data of the first sensor 201 and the second sensor 202 detected at time t.

[0016] The first demarcation line calculation determination unit 101 receives as input a signal related to observation data from the first sensor 201 and calculates a first distance between the target vehicle 1 and the demarcation line. The first demarcation line calculation determination unit 101 determines whether the target vehicle 1 has crossed a demarcation line based on the calculated first distance. The first demarcation line calculation determination unit 101 outputs the determination result to the traveling demarcation line matching unit 113 together with the calculated first distance.

[0017] The second lane line calculation determination unit 102 receives as input a signal related to the observation data from the second sensor 202 and calculates a second distance between the target vehicle 1 and the lane line. The second lane line calculation determination unit 102 determines whether the target vehicle 1 has crossed a lane line based on the calculated second distance. The second lane line calculation determination unit 102 outputs the determination result to the traveling lane matching unit 113 together with the calculated second distance.

[0018] The traveling lane matching unit 113 receives as input the outputs from the first lane line calculation determination unit 101 and the second lane line calculation determination unit 102. The traveling lane matching unit 113 may transmit the first distance calculated by the first lane line calculation determination unit 101 and the second distance calculated by the second lane line calculation determination unit 102 to the position estimation unit 114 without matching them. In addition, the traveling lane matching unit 113 may match one or both of the first distance and the second distance and transmit them to the position estimation unit 114.

[0019] The traveling lane matching unit 113 determines whether to match the first distance or the second distance based on whether the target vehicle 1 has crossed a lane line determined by the first lane line calculation determination unit 101 and whether the target vehicle 1 has crossed a lane line determined by the second lane line calculation determination unit 102. The position estimation unit 114 receives the output from the traveling lane matching unit 113 as input, and estimates and outputs the position of the target vehicle 1 based on the observation data of the first sensor 201 and the second sensor 202.

[0020] <Hardware Configuration of Vehicle Position Estimation Device> FIG. 2 is a hardware configuration diagram of the vehicle position estimation device 100. Although FIG. 2 can also be applied to the vehicle position estimation devices 100a and 100b, the vehicle position estimation device 100 will be described as a representative example. In this embodiment, the vehicle position estimation device 100 is an electronic control device for estimating the position of a vehicle using the distance between the vehicle and a lane marking. Each function of the vehicle position estimation device 100 is realized by a processing circuit provided in the vehicle position estimation device 100. Specifically, the vehicle position estimation device 100 includes, as processing circuits, an arithmetic processing device 90 (computer) such as a CPU (Central Processing Unit), a storage device 91 that exchanges data with the arithmetic processing device 90, an input circuit 92 that inputs an external signal to the arithmetic processing device 90, and an output circuit 93 that outputs a signal from the arithmetic processing device 90 to the outside. Each piece of hardware such as the arithmetic processing device 90, the storage device 91, the input circuit 92, and the output circuit 93 are connected to each other by a wired network such as a bus or a wireless network.

[0021] The arithmetic processing device 90 may be an application specific integrated circuit (ASIC), an integrated circuit (IC), a digital signal processor (DSP), a graphics processing unit (GPU), a field programmable gate array (FPGA), various logic circuits, various signal processing circuits, etc. Also, the arithmetic processing device 90 may be a plurality of devices of the same type or different types, and each process may be shared and executed. The storage device 91 may be a random access memory (RAM) configured to be able to read and write data from the arithmetic processing device 90, a read only memory (ROM) configured to be able to read data from the arithmetic processing device 90, etc. As the storage device 91, a non-volatile or volatile semiconductor memory such as a flash memory, a solid state drive (SSD), an EPROM, an EEPROM, etc., a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD, etc. may be used. The input circuit 92 is connected to various sensors including the output signals of the first sensor 201 and the second sensor 202, switches, and communication lines, and includes an A / D converter, communication circuit, and the like that input the output signals and communication information of these sensors and switches to the arithmetic processing device 90. The output circuit 93 includes a drive circuit, communication circuit, and the like that outputs control signals from the arithmetic processing device 90. The interfaces of the input circuit 92 and the output circuit 93 may be based on specifications such as CAN (Control Area Network) (registered trademark), Ethernet (registered trademark), USB (Universal Serial Bus) (registered trademark), DVI (Digital Visual Interface) (registered trademark), and HDMI (High-Definition Multimedia Interface) (registered trademark).

[0022] Each function of the vehicle position estimation device 100 is realized by the arithmetic processing device 90 executing software (programs) stored in a storage device 91 such as a ROM, and cooperating with other hardware of the vehicle position estimation device 100 such as the storage device 91, an input circuit 92, and an output circuit 93. Setting data such as thresholds and judgment values ​​used by the vehicle position estimation device 100 is stored in the storage device 91 such as a ROM as part of the software (programs). Each function of the vehicle position estimation device 100 may be configured as a software module, or may be configured as a combination of software and hardware.

[0023] <Vehicle lane change> FIG. 3 is a diagram showing lane changing of the vehicle 1 according to the first embodiment. FIG. 4 is a diagram showing the distance to a marking line when the vehicle 1 according to the first embodiment changes lanes. As shown in FIG. 3, a case will be described in which the target vehicle 1 changes its driving lane from the left lane to the right lane. In this case, a case will be described in which the distance to the nearest lane on the left side of the target vehicle 1 (hereinafter referred to as the distance to the left marking line) is used as a value representing the position of the target vehicle 1 in the lane. The distance to the left marking line of the target vehicle 1 varies as shown in the graph in FIG. 4.

[0024] The vertical axis of the graph shown in Fig. 4 is the distance to the left lane marking. The distance to the left lane marking is positive when it is from the center line of the target vehicle 1 to the left of the target vehicle 1's traveling direction. In the example shown in Fig. 3, the lane nearest to the left of the target vehicle 1 switches from lane marking A to lane marking B due to a change in driving lane. Therefore, as shown in Fig. 4, at a certain time (lane marking crossing determination time), the distance to the left lane marking changes suddenly and discontinuously.

[0025] As shown in Fig. 3, the position of the target vehicle 1 can also be expressed using the distance to the nearest lane on the right side of the target vehicle 1 (hereinafter referred to as the distance to the right-side marking line). The distance to the right-side marking line also switches from marking line B to marking line C when the vehicle is changing lanes. Therefore, the distance to the right-side marking line also changes suddenly when the target vehicle 1 crosses the marking line.

[0026] Fig. 5 is a diagram showing the distance to the lane marking measured by the first sensor 201 and the second sensor 202 when the vehicle 1 according to the embodiment 1 changes lanes. In the example of the change of the driving lane shown in Fig. 3, Fig. 5 shows an example of the observation data related to the distance to the left lane marking outputted from the first sensor 201 and the second sensor 202. As described above, the distance to the left lane marking observed by the first sensor 201 and the second sensor 202 shows a discontinuous change at the crossing time T1 or the crossing time T2.

[0027] The crossing time T1 at which the observation data of the first sensor 201 varies discontinuously does not necessarily coincide with the crossing time T2 at which the observation data of the second sensor 202 varies discontinuously. This may occur due to differences in the installation positions of the sensors, the observation means, errors between sensors, etc.

[0028] For example, the first sensor 201 is a sensor that detects the lane markings based on an image acquired by an imaging element, and the time when it is determined that the target vehicle 1 has changed lanes based on the field of view of the image is the crossing time T1. For example, the second sensor 202 is a sensor that calculates the latitude and longitude of the target vehicle 1 by positioning with an artificial satellite and comparing it with a map, and the time when this position crosses the lane markings on the map is the crossing time T2. In this case, since the first sensor 201 and the second sensor 202 have significantly different measuring means, the crossing time T1 and the crossing time T2 do not necessarily match. Furthermore, even if the first sensor 201 and the second sensor 202 have been calibrated in advance in the past so that the crossing time T1 and the crossing time T2 match, if the errors contained in each sensor vary over time, it cannot be said that the crossing time T1 and the crossing time T2 always match.

[0029] 5, between crossing time T1 and crossing time T2, the first sensor 201 and the second sensor 202 indicate the position of the target vehicle 1 based on different distances to the lane markings, causing a mismatch. Due to the mismatch, the difference in distances to the lane markings between the sensors increases significantly.

[0030] 5, in the time period between crossing time T1 and crossing time T2, the first sensor 201 regards the left lane marking (line B) after the target vehicle 1 changes lanes as the nearest left lane marking, and the second sensor 202 regards the left lane marking (line A) before the target vehicle 1 changes lanes as the nearest left lane marking. Therefore, between crossing time T1 and crossing time T2, the difference between the distance to the left lane marking measured by the first sensor 201 and the second sensor 202 increases significantly. This causes a decrease in the accuracy of the position estimation of the target vehicle 1 based on the information from both sensors.

[0031] <Distance Consistency> 6 is a diagram showing the matching of the distance to the lane marking by the first sensor 201 and the second sensor 202 when the vehicle 1 according to the first embodiment changes lanes. Matching refers to matching without any malfunction, and matching to a value considered to be correct. Here, the traveling lane matching unit 113 matches the distance to the left lane marking. As shown in FIG. 6, processing is performed so that the time at which the distance to the left lane marking suddenly changes is matched between the first sensor 201 and the second sensor 202.

[0032] Specifically, the following process is performed. First, the first lane line calculation determination unit 101 determines that the target vehicle 1 crossed the lane line at the crossing time T1 based on the input from the first sensor 201. Based on this determination, the traveling lane matching unit 113 determines that a discrepancy has occurred between the first sensor 201 and the second sensor 202 in the driving lane in which the target vehicle 1 is traveling. Then, a conversion is performed to align the driving lane in the observation data of the second sensor 202 with the driving lane in the observation data of the first sensor 201. In other words, the distance to the left lane line measured by the second sensor 202 is replaced with the distance to the left lane line measured by the first sensor 201. The traveling lane matching unit 113 outputs the distance to the left lane line measured by the first sensor 201 and the aligned distance to the left lane line measured by the second sensor 202 to the position estimation unit 114.

[0033] Thereafter, at time T2, the second lane line calculation determination unit 102 determines that the target vehicle 1 has crossed the lane line based on the input observation data of the second sensor 202. Based on this determination, the traveling lane matching unit 113 determines that the difference in the traveling lanes between the first sensor 201 and the second sensor 202 has been resolved. Then, the matching process of the distance to the left lane line by the second sensor 202, which was performed between crossing time T1 and crossing time T2, is stopped. Through these processes, the observation data of each sensor input to the position estimation unit 114 is aligned so that the distance from lane line A to lane line B suddenly changes overall at the same crossing time T1, as shown in FIG.

[0034] <Processing by vehicle position estimation device> Fig. 7 is a first flowchart showing the processing of the vehicle position estimation device 100 according to the embodiment 1. Fig. 8 is a second flowchart showing the processing of the vehicle position estimation device 100, which is a continuation of Fig. 7.

[0035] 7 and 8 are flowcharts showing the operations of the first lane line calculation determination unit 101, the second lane line calculation determination unit 102, the traveling lane matching unit 113, and the position estimation unit 114 from when a signal of observation data at the current time is input from each sensor to when an estimated position of the target vehicle 1 at the current time is output. The processing of the flowchart in FIG. 7 is executed at predetermined time intervals (e.g., every 10 ms). The processing of the flowchart in FIG. 7 may be executed not at predetermined time intervals, but each time the vehicle travels a predetermined distance, each time a sensor obtains new information, or in response to an event such as an external instruction.

[0036] 7 is started, and in step ST101, the first lane line calculation determination unit 101 calculates a first distance between the target vehicle 1 and the lane line based on the observation data of the first sensor 201. Then, based on the calculated first distance, it determines whether the target vehicle 1 has crossed the lane line at the current time. If it is determined that the target vehicle 1 has crossed the lane line, a first crossing flag is set.

[0037] This determination of whether the lane marking has been crossed can be determined, for example, based on the amount of change in the value of the distance between the lane marking and the target vehicle 1. It may be determined that the lane marking has been crossed when the first distance has changed by a larger amount than a predetermined crossing determination distance within a predetermined crossing determination time.

[0038] Alternatively, the distance between the lane marking and the target vehicle 1 at the time when the observation data of the first sensor 201 was last valid (the past time closest to the current time) is compared with the distance between the lane marking and the target vehicle 1 at the current time when the observation data is valid. If the difference between the comparison results exceeds a certain value, it is determined that the target vehicle 1 has crossed the lane marking. Here, "the observation data is valid" can be defined as a case where the reliability of the observation data of the first sensor 201 is equal to or higher than a certain value. For example, if the first sensor 201 is a type of sensor that measures the distance between the lane marking and the target vehicle 1 using an imaging element, if the lane marking is blurred or if there is a lot of noise in the imaging element, it can be considered that the reliability of the observation data is low and the observation data is not valid. In this way, it is possible to determine whether the target vehicle 1 has crossed the lane marking by comparing the last valid observation data with the current observation data when the observation data is valid. In this way, it is possible to avoid a situation where an erroneous determination is made that the target vehicle 1 has crossed the lane marking even if the accuracy of the observation data temporarily decreases.

[0039] As a determination method other than the above example, the crossing of the lane marking may be determined using observation data specific to the first sensor 201. For example, if the first sensor 201 is a type of sensor that calculates the distance between the lane marking and the target vehicle 1 by comparing the positioning result with a satellite with a map, the change in the traveling lane may be determined. The crossing of the lane marking can be determined based on whether the lane in which the target vehicle 1 was traveling at the time when the observation data was last valid is the same as the lane in which the target vehicle 1 is currently traveling on the map. In the case of this type of sensor, "the observation data is valid" can be determined based on the reliability that represents the quality of the positioning signal with the satellite. In this determination method example as well, by comparing the last valid observation data with the current observation data, it is possible to avoid a situation in which an erroneous crossing determination is made even if the accuracy of the observation data temporarily decreases.

[0040] In addition, the angle of the traveling direction of the target vehicle 1 with respect to the lane marking may be used in combination with the above determination. For example, the closer the angle of the traveling direction with respect to the lane marking is to a right angle, the more relaxed the determination condition for crossing the lane marking may be.

[0041] In the above determination, the observation data for both the nearest lane line on the left and the nearest lane line on the right may be used, or only one of them may be used. For example, if the crossing of the nearest lane line on the right is determined based on the observation data for the nearest lane line on the right, the observation data for the nearest lane line on the left does not necessarily have to be used. Note that in this step, it is also determined whether the lane line on the right or the lane line on the left has been crossed.

[0042] In step ST102, the first lane line calculation determination unit 101 performs a conditional branch of the process according to the determination result in step ST101. In step ST102, it is determined whether the first crossing determination flag is set. If the first crossing determination flag is not set (determination is NO), the process proceeds to step ST201.

[0043] In step ST102, if the first crossing determination flag is set (determination is YES), the process proceeds to step ST103. In step ST103, the first lane line calculation determination unit 101 stores the crossing time T1 at which it is determined that the target vehicle 1 has crossed the lane line based on the first distance calculated from the signal from the first sensor 201. Note that this crossing time T1 is a value that is not erased but is stored even after all the processes in Figures 7 and 8 are completed. Also, the initial value of the crossing time T1 is the observation start time of the first sensor 201.

[0044] In step ST201, the second lane line calculation determination unit 102 calculates a second distance between the target vehicle 1 and the lane line based on the observation data of the second sensor 202. Then, based on the calculated second distance, it determines whether the target vehicle 1 has crossed the lane line at the current time. If it is determined that the target vehicle 1 has crossed the lane line, a second crossing flag is set.

[0045] The determination of whether the lane line has been crossed in step ST201 can be made, for example, based on the amount of change in the value of the distance between the lane line and the target vehicle 1, as in step ST101. Also, as in step ST101, the determination of whether the lane line has been crossed may be made by comparing the most recent data when the observation data is valid. Also, as in step ST101, the determination of whether the lane line has been crossed may be made using observation data specific to the second sensor 202. Note that in this step, it is also determined whether the lane line has been crossed on the right or on the left.

[0046] In step ST202, the second lane line calculation determination unit 102 performs a conditional branch of the process depending on the determination result in step ST201. In step ST202, it is determined whether the second crossing determination flag is set. If the second crossing determination flag is not set (determination is NO), the process proceeds to step ST204.

[0047] In step ST202, if the second crossing determination flag is set (determination is YES), the process proceeds to step ST203. In step ST203, the second lane line calculation determination unit 102 stores the crossing time T2 at which it is determined that the target vehicle 1 has crossed the lane line based on the second distance calculated from the signal from the second sensor 202. Note that this crossing time T2 is a value that is not erased but is stored even after all the processes in Figures 7 and 8 are completed. Also, the initial value of the crossing time T2 is the observation start time of the second sensor 202.

[0048] In step ST204, the first crossing determination flag and the second crossing determination flag are cleared, and the process proceeds to step ST301 in FIG.

[0049] 8, the traveling lane matching unit 113 judges whether or not the first lane line calculation determination unit 101 judged the crossing of the lane line at a time close to the present before the second lane line calculation determination unit 102. Specifically, if the difference between the current time and the crossing time T1 is less than the matching duration TP1 (indicating that the crossing time T1 has been recently updated) and the crossing time T1 minus the crossing time T2 is greater than the matching prohibition time TP2 (indicating that the crossing time T2 has not been updated since the matching prohibition time TP2 compared to the crossing time T1), this judgment is regarded as true.

[0050] Here, the consistency duration TP1 and the consistency prohibition time TP2 are parameter values ​​related to preset times. The consistency duration TP1 is a relatively short time from the start of consistency processing until the end of consistency. The consistency prohibition time TP2 is a prohibition time from the execution of consistency processing until the start of a new consistency processing is permitted, and is a longer time than the consistency duration TP1. If the determination in this step ST301 is true (determination is YES), proceed to step ST401. If the determination in step ST301 is false (determination is NO), proceed to step ST302.

[0051] In step ST302, the traveling lane matching unit 113 judges whether or not the second lane line calculation determination unit 102 has determined the crossing of a lane line at a time close to the present before the first lane line calculation determination unit 101. Specifically, if the difference between the current time and the crossing time T2 is less than the matching duration TP1 (indicating that the crossing time T2 has been recently updated) and the crossing time T2 - the crossing time T1 is greater than the matching prohibition time TP2 (indicating that the crossing time T1 has not been updated since the matching prohibition time TP2 compared to the crossing time T2), this judgment is deemed to be true.

[0052] If the determination in step ST302 is true (determination is YES), the process proceeds to step ST402, whereas if the determination in step ST302 is false (determination is NO), the process proceeds to step ST403.

[0053] In step ST401, the traveling lane matching unit 113 matches the second distance based on the observation data of the second sensor 202 with the first distance based on the observation data of the first sensor 201. This results in matching so that the traveling lane of the target vehicle 1 based on the observation data of the second sensor 202 becomes the same as the traveling lane of the target vehicle 1 based on the observation data of the first sensor 201. The first distance based on the observation data of the first sensor 201 does not match.

[0054] 6, the second distance after the crossing time T1 is replaced with the first distance. This matching aligns the driving lane of the target vehicle 1 with the lane in which the target vehicle 1 crossed the lane marking at the crossing time T1 in the observation data of both sensors. Similar matching is also performed when it is determined that the target vehicle 1 has crossed the left lane marking. In step ST401, the matched second distance and the unmatched first distance are passed to the position estimation unit 114.

[0055] In step ST402, the traveling lane matching unit 113 matches the first distance based on the observation data of the first sensor 201 with the second distance based on the observation data of the second sensor 202. This results in matching so that the traveling lane of the target vehicle 1 based on the observation data of the first sensor 201 is the same as the traveling lane of the target vehicle 1 based on the observation data of the second sensor 202. The second distance based on the observation data of the second sensor 202 does not match.

[0056] By matching the first distance based on the observation data of the first sensor 201, the first distance after the crossing time T2 is replaced with the second distance. By this matching, the driving lane of the target vehicle 1 is aligned with the lane in which the target vehicle 1 crossed the lane marking at the crossing time T2 in the observation data of both sensors. A similar matching is also performed when it is determined that the target vehicle 1 has crossed the left lane marking. By this step ST402, the matched first distance and the unmatched second distance are passed to the position estimation unit 114.

[0057] In step ST403, the traveling section matching unit 113 does not perform matching processing on either the first distance or the second distance. The first distance based on the unmatched observation data of the first sensor 201 and the second distance based on the unmatched observation data of the second sensor 202 are passed to the position estimation unit 114.

[0058] In step ST501, the position estimation unit 114 receives the first distance and the second distance based on the observation data of each sensor that has been matched or not matched by any of steps ST401, ST402, and ST403. The matching process in steps ST401 and ST402 is performed on the first distance and the second distance passed to the position estimation unit 114. In contrast, the calculation of the first distance and the determination of whether or not the marking line has been crossed, which are performed by the first marking line calculation determination unit 101, and the calculation of the second distance and the determination of whether or not the marking line has been crossed, which are performed by the second marking line calculation determination unit 102, are continued without being affected by the matching process.

[0059] The position estimation unit 114 calculates an estimated position of the target vehicle 1 using the first distance and the second distance. The calculation of the estimated position uses an existing sensor fusion technique. For example, a weight according to the accuracy of each sensor may be set for the observation data, and the weighted average of the first distance based on the observation data of the first sensor 201 and the second distance based on the observation data of the second sensor 202 may be used as the estimated position of the target vehicle 1. Also, for example, as disclosed in Patent Document 1, a process may be performed to estimate the position of the vehicle so that the deviation between the first distance based on the observation data of the first sensor 201 and the second distance based on the observation data of the second sensor 202 is minimized.

[0060] According to the vehicle position estimation device 100 according to the first embodiment configured as described above, the following effects can be obtained. In the vehicle position estimation device 100, the first demarcation line calculation / determination unit 101 and the second demarcation line calculation / determination unit 102 determine whether the target vehicle 1 has crossed a demarcation line based on the distance calculated by the observation data of each sensor. Then, based on the determination of whether the target vehicle 1 has crossed a demarcation line in the traveling lane matching unit 113, matching can be performed to align the traveling lanes of the target vehicle 1 based on the distance calculated by the observation data of each sensor. Therefore, an error in regarding different demarcation lines as the same when the observation data of each sensor is different is suppressed. Then, the position estimation unit 114 estimates the position of the target vehicle 1 based on the matched first distance and second distance. Therefore, even when the target vehicle 1 changes the traveling lane, the effect of suppressing a decrease in the accuracy of estimating the position of the target vehicle 1 can be obtained.

[0061] Furthermore, the first lane line calculation determination unit 101 and the second lane line calculation determination unit 102 determine whether the target vehicle 1 has crossed a lane line based on a comparison of the observation data from the last time the signals input from the first sensor 201 and the second sensor 202 were valid in the past with the currently valid observation data. This makes it possible to prevent erroneous determination that the target vehicle 1 has crossed a lane line even if the observation data of the first sensor 201 or the second sensor 202 becomes temporarily invalid.

[0062] The lane matching unit 113 enables the first lane line calculation / determination unit 101 and the second lane line calculation / determination unit 102 to perform matching to align the timing of determining whether the target vehicle 1 has crossed a lane line with the recognition of the lane the target vehicle 1 is traveling in. As a result, an effect is obtained in which the accuracy of estimating the position of the target vehicle 1 is prevented from decreasing even when the target vehicle 1 is crossing a lane line.

[0063] 2. Second embodiment <Configuration of vehicle position estimation device> The vehicle position estimation device 100 according to the second embodiment is obtained by modifying the processing contents by modifying the software of the vehicle position estimation device 100 according to the first embodiment. Since no modification is required for the hardware, the configuration in FIG. 1 can be applied.

[0064] <Distance Consistency> Fig. 9 is a diagram showing the distance to the lane marking measured by the first sensor 201 and the second sensor 202 when the vehicle 1 according to the embodiment 2 changes lanes. Fig. 10 is a first diagram showing the consistency of the distance to the lane marking measured by the first sensor 201 and the second sensor 202 when the vehicle 1 according to the embodiment 2 changes lanes. Fig. 11 is a second diagram showing the consistency of the distance to the lane marking measured by the first sensor 201 and the second sensor 202.

[0065] A case will be described where the target vehicle 1 changes the driving lane from the left lane to the right lane, as shown in Fig. 3. The upper vertical axis of the graph shown in Fig. 9 represents the distance to the left lane marking detected by the first sensor 201. The lower vertical axis of the graph shown in Fig. 9 represents the distance to the right lane marking detected by the second sensor 202.

[0066] The distance to the left lane line is considered positive when it is the distance to the left of the center line of the target vehicle 1 in the direction of travel of the target vehicle 1. The distance to the right lane line is considered negative when it is the distance to the right of the center line of the target vehicle 1 in the direction of travel of the target vehicle 1. In the example shown in FIG. 9, the lane to the left of the target vehicle 1 switches from lane line A to lane line B due to a change in driving lane. The lane to the right of the target vehicle 1 switches from lane line B to lane line C due to a change in driving lane.

[0067] 9, the distance to the right-side lane marking B measured by the second sensor 202 becomes 0 at time T2, and then the sign is reversed. This indicates that, while lane marking B was positioned to the right of the center line of the target vehicle 1 in the traveling direction of the target vehicle 1, lane marking B shifted to the left of the target vehicle 1 after time T2.

[0068] The second lane line calculation determination unit 102 can recognize time T2 as the crossing time because the position of the lane line has switched from left to right. The traveling lane line matching unit 113 matches the distance to the left lane line measured by the first sensor 201 based on the crossing time T2.

[0069] 10, the distance to the right lane marking measured by the second sensor 202 from time T2 to time T1 is used to align the distance to the left lane marking measured by the first sensor 201. This alignment makes it possible to align the distance to the left lane marking measured by the first sensor 201 with the data that suddenly changes at time T1, as shown in FIG.

[0070] 11, the distance to the right-side lane marking measured by the second sensor 202 can also be matched using the distance between the crossed lane marking B and the adjacent lane marking C to the right of the crossed lane marking B. This match allows the distance to the right-side lane marking measured by the second sensor 202 to be matched to the data that suddenly changes at time T2.

[0071] By the above process, even if the target vehicle 1 changes driving lanes, the first sensor 201 and the second sensor 202 will erroneously regard different marking lines as being the same at the input stage to the position estimation unit 114. A more detailed process will be described later. Note that, although the above example has been described assuming that time T2 is less than time T1 (time T2 occurs first), this is not limiting. In other words, the same effect can be achieved even if it is determined that the target vehicle 1 has crossed a marking line first based on the first distance measured by the first sensor 201.

[0072] <Processing by vehicle position estimation device> Fig. 12 is a first flowchart showing the processing of the vehicle position estimation device 100 according to the embodiment 2. Fig. 13 is a second flowchart showing the processing of the vehicle position estimation device 100, which is a continuation of Fig. 12.

[0073] 12 and 13 are flowcharts showing the operations of the first lane line calculation determination unit 101, the second lane line calculation determination unit 102, the traveling lane matching unit 113, and the position estimation unit 114 from when a signal of observation data at the current time is input from each sensor to when an estimated position of the target vehicle 1 at the current time is output. The processing of the flowchart in FIG. 12 is executed at predetermined time intervals (e.g., every 10 ms). The processing of the flowchart in FIG. 7 may be executed not at predetermined time intervals, but each time the vehicle travels a predetermined distance, each time a sensor obtains new information, or in response to an event such as an external instruction.

[0074] The flowchart of Fig. 12 according to the second embodiment is obtained by changing steps ST101 and ST201 in the flowchart of Fig. 7 according to the first embodiment to steps ST111 and ST211. The flowchart of Fig. 13 is obtained by changing steps ST401 and ST402 in the flowchart of Fig. 8 according to the first embodiment to steps ST411 and ST412. The different processes will be described below.

[0075] 12, the process starts, and in step ST111, the first lane line calculation determination unit 101 calculates a first distance between the target vehicle 1 and the lane line based on the observation data of the first sensor 201. Then, based on the calculated first distance, it determines whether the target vehicle 1 has crossed the lane line at the current time. If it is determined that the target vehicle 1 has crossed the lane line, a first crossing flag is set.

[0076] This determination of whether the lane marking has been crossed can be determined, for example, based on the amount of change in the value of the distance between the lane marking and the target vehicle 1. It may be determined that the lane marking has been crossed when the first distance changes by a greater amount than a predetermined crossing determination distance within a predetermined crossing determination time. Furthermore, it can be determined that the target vehicle 1 has crossed the lane marking when the position of the lane marking changes from left to right with respect to the target vehicle 1.

[0077] For example, the first demarcation line calculation and determination unit 101 may calculate a first right-side distance between the target vehicle 1 and a demarcation line on the right side of the target vehicle 1 and determine whether or not the target vehicle 1 has crossed the right-side demarcation line based on the first right-side distance. Alternatively, the first demarcation line calculation and determination unit 101 may calculate a first left-side distance between the target vehicle 1 and a demarcation line on the left side of the target vehicle 1 and determine whether or not the target vehicle 1 has crossed the left-side demarcation line based on the first left-side distance. Alternatively, the first demarcation line calculation and determination unit 101 may perform both the calculation of the first right-side distance and the determination of whether or not the target vehicle 1 has crossed the right-side demarcation line, and the calculation of the first left-side distance and the determination of whether or not the target vehicle 1 has crossed the left-side demarcation line.

[0078] In step ST211, the second lane line calculation determination unit 102 calculates a second distance between the target vehicle 1 and the lane line based on the observation data of the second sensor 202. Then, based on the calculated second distance, it determines whether the target vehicle 1 has crossed the lane line at the current time. If it is determined that the target vehicle 1 has crossed the lane line, a second crossing flag is set.

[0079] The determination of whether the lane marking has been crossed in step ST211 can be made, as in step ST111, based on, for example, the amount of change in the value of the distance between the lane marking and the target vehicle 1. It may be determined that the lane marking has been crossed when the first distance changes more than a predetermined crossing determination distance within a predetermined crossing determination time. Furthermore, it can be determined that the target vehicle 1 has crossed the lane marking when the position of the lane marking changes from left to right with respect to the target vehicle 1.

[0080] For example, the second lane line calculation and determination unit 102 may calculate a second right-side distance between the target vehicle 1 and a lane line on the right side of the target vehicle 1 and determine whether the target vehicle 1 has crossed the right-side lane line based on the second right-side distance. Alternatively, the second lane line calculation and determination unit 102 may calculate a second left-side distance between the target vehicle 1 and a lane line on the left side of the target vehicle 1 and determine whether the target vehicle 1 has crossed the left-side lane line based on the second left-side distance. Alternatively, the second lane line calculation and determination unit 102 may perform both the calculation of the second right-side distance and the determination of whether the target vehicle 1 has crossed the right-side lane line, and the calculation of the second left-side distance and the determination of whether the target vehicle 1 has crossed the left-side lane line.

[0081] 13, in step ST411, the traveling lane matching unit 113 starts matching the first distance based on the observation data of the first sensor 201 and the second distance based on the observation data of the second sensor 202 based on the distance to another lane line. Specifically, as described in FIG. 11, the matching process is performed based on the distance to an adjacent lane line.

[0082] In step ST412, the driving lane line matching unit 113 starts matching the first distance based on the observation data of the first sensor 201 and the second distance based on the observation data of the second sensor 202 based on the distance to another lane line.

[0083] For example, when either the first lane line calculation determination unit 101 or the second lane line calculation determination unit 102 determines that the target vehicle 1 has crossed the lane line from left to right, the traveling lane matching unit 113 may start matching based on the distance between the target vehicle 1 in the first right-side distance and the second right-side distance and the lane line adjacent to the right of the lane line crossed by the target vehicle 1. Alternatively, at this time, the traveling lane matching unit 113 may start matching based on the distance between the target vehicle 1 in the first left-side distance and the second left-side distance and the lane line crossed by the target vehicle 1.

[0084] Furthermore, when either the first lane line calculation determination unit 101 or the second lane line calculation determination unit 102 determines that the target vehicle 1 has crossed the lane line from right to left, the traveling lane matching unit 113 may start matching the first right-side distance and the second right-side distance based on the distance between the target vehicle 1 and the lane line crossed by the target vehicle 1. Alternatively, at this time, the traveling lane matching unit 113 may start matching the first left-side distance and the second left-side distance based on the distance between the target vehicle 1 and the lane line adjacent to the left of the lane line crossed by the target vehicle 1.

[0085] The vehicle position estimation device 100 according to the second embodiment configured as above can also provide the same effects as those of the first embodiment. The position estimation unit 114 estimates the position of the target vehicle 1 based on the matched first distance and second distance. Therefore, even when the target vehicle 1 changes driving lanes, it is possible to obtain an effect of suppressing a decrease in the accuracy of estimating the position of the target vehicle 1.

[0086] 3. Third embodiment <Configuration of vehicle position estimation device> 14 is a configuration diagram of a vehicle position estimation device 100a according to the third embodiment. The configuration diagram of FIG. 14 according to the third embodiment differs from the configuration diagram of vehicle position estimation device 100 of FIG. 1 according to the first embodiment only in that an input signal from traveling lane changing operation information acquisition unit 213 is added.

[0087] In the first embodiment, the first lane line calculation / determination unit 101 and the second lane line calculation / determination unit 102 are configured to determine whether the target vehicle 1 has crossed a lane line based on the signals of the first sensor 201 and the second sensor 202. However, due to noise in the observation data of the sensors, etc., it may be erroneously determined that the target vehicle 1 has crossed a lane line even though the target vehicle 1 has not actually changed lanes. When such an erroneous determination occurs, the accuracy of the estimated position of the target vehicle 1 output by the position estimation unit 114 is significantly degraded.

[0088] Therefore, the vehicle position estimation device 100a according to the third embodiment is provided with a lane change operation information acquisition unit 213 that acquires operation information when the target vehicle 1 changes lanes, and the output of the lane change operation information acquisition unit 213 is used for the judgment. The information acquired by the lane change operation information acquisition unit 213 may include, for example, information on whether the turn signal lights of the target vehicle 1 are on or off, the steering angle of the target vehicle 1, the yaw rate of the target vehicle 1, and biometric data of the driver of the target vehicle 1. This configuration can reduce the frequency of errors in determining that the target vehicle 1 has crossed a lane marking even when the target vehicle 1 has not actually changed lanes. As a result, the deterioration of the accuracy of the estimated position of the target vehicle 1 can be suppressed.

[0089] The first lane line calculation determination unit 101a and the second lane line calculation determination unit 102a receive as input lane change operation information output from the driving lane change operation information acquisition unit 213. The first lane line calculation determination unit 101a receives as input observation data from the first sensor 201 and lane change operation information from the driving lane change operation information acquisition unit 213, and outputs to the driving lane matching unit 113 a first distance from the target vehicle 1 to the lane line and a determination result as to whether the target vehicle 1 has crossed the lane line.

[0090] The second lane marking calculation determination unit 102a receives as input observation data from the second sensor 202 and lane change operation information from the lane marking change operation information acquisition unit 213, and outputs to the lane marking consistency unit 113 a second distance from the target vehicle 1 to the lane marking line and a determination result as to whether the target vehicle 1 has crossed the lane marking line.

[0091] <Processing by vehicle position estimation device> 15 is a first flowchart showing the process of the vehicle position estimation device 100a according to the embodiment 3. The continuation of the flowchart in FIG.

[0092] 15 and 8 are flowcharts showing the operations of the first lane line calculation determination unit 101a, the second lane line calculation determination unit 102a, the lane matching unit 113, and the position estimation unit 114 from when signals at the current time are input from the first sensor 201, the second sensor 202, and the lane change operation information acquisition unit 213 to when the estimated position of the target vehicle 1 at the current time is output. The processing of the flowchart in FIG. 15 is executed at predetermined time intervals (for example, every 10 ms). The processing of the flowchart in FIG. 15 may be executed not at predetermined time intervals, but each time the vehicle travels a predetermined distance, each time the sensor obtains new information, or in response to an event such as an external instruction.

[0093] 15 according to the third embodiment is obtained by changing steps ST101 and ST201 in the flowchart of FIG 7 according to the first embodiment to steps ST121 and ST221. The different processes will be described below.

[0094] 15, the process starts, and in step ST121, the first lane line calculation determination unit 101a calculates a first distance between the target vehicle 1 and the lane line based on the observation data of the first sensor 201. Then, based on the calculated first distance and lane change operation information from the lane change operation information acquisition unit 213, it is determined whether the target vehicle 1 has crossed the lane line at the current time.

[0095] This determination of whether the target vehicle 1 has crossed the lane line is performed by adding, in addition to the determination shown in the first embodiment, for example, that the target vehicle 1 has its turn signal lights on as a condition for determining whether the target vehicle 1 has crossed the lane line. That is, if the target vehicle 1 is considered to be crossing the lane line based on the first distance and the turn signal lights are on in the same direction as the direction in which the target vehicle 1 will cross, it is determined that the target vehicle 1 has crossed the lane line. If it is determined that the target vehicle 1 has crossed the lane line, a first crossing flag is set.

[0096] As another type of lane change operation information, a condition for determining whether the target vehicle 1 is crossing may be added to the condition for determining whether the target vehicle 1 is crossing, the condition being that the steering wheel is turned in the crossing direction by a predetermined angle or more as determined by a steering angle sensor of the target vehicle 1. Furthermore, when the yaw rate of the target vehicle 1 is used, the condition for determining whether the target vehicle 1 is crossing may be added to the condition for determining whether the target vehicle 1 is crossing, the condition being that the absolute value of the yaw rate of the target vehicle 1 is equal to or greater than a certain value. Furthermore, when the biometric data of the driver of the target vehicle 1 is used as another type of lane change operation information, the condition for determining whether the target vehicle 1 is crossing may be added to the condition for determining whether the target vehicle 1 is crossing, the condition being that the biometric data indicates that the driver of the target vehicle 1 intends to change lanes.

[0097] In step ST221, the second lane marking calculation determination unit 102a calculates a second distance between the target vehicle 1 and the lane marking based on the observation data of the second sensor 202. Then, based on the calculated second distance and the lane change operation information from the lane change operation information acquisition unit 213, it is determined whether the target vehicle 1 has crossed the lane marking at the current time.

[0098] This determination of whether the target vehicle 1 has crossed the lane line is performed, as in step ST121, by adding, for example, that the target vehicle 1 has its turn signal lights on to the conditions for determining whether the target vehicle 1 has crossed the lane line. That is, if the target vehicle 1 is considered to be crossing the lane line based on the second distance and the turn signal lights in the same direction as the direction in which the target vehicle 1 is crossing are on, it is determined that the target vehicle 1 has crossed the lane line. If it is determined that the target vehicle 1 has crossed the lane line, a first crossing flag is set. As in step ST121, other types of information can also be used as lane change operation information.

[0099] According to the vehicle position estimation device 100a according to the third embodiment configured as described above, a lane line crossing determination is performed using the lane change operation information output from the lane change operation information acquisition unit 213. This configuration makes it possible to suppress the occurrence of an error in determining that the target vehicle 1 has crossed a lane line even though the target vehicle 1 has not actually changed lanes due to noise in the observation data of the sensor, etc. This provides the effect of suppressing a decrease in the accuracy of estimating the position of the target vehicle 1.

[0100] 4. Fourth embodiment <Configuration of vehicle position estimation device> 16 is a configuration diagram of a vehicle position estimation device 100b according to the fourth embodiment. In the first embodiment, the position of the target vehicle 1 is estimated based on observation data from the first sensor 201 and the second sensor 202. However, there may be cases where both the first sensor 201 and the second sensor 202 are unavailable due to the observation environment or factors within the device. Furthermore, there may be cases where the observation accuracy of both the first sensor 201 and the second sensor 202 is significantly degraded.

[0101] Therefore, the vehicle position estimation device 100b according to the fourth embodiment is configured to estimate the position of the target vehicle 1 based on the observation data of N sensors (N is an integer equal to or greater than 3) and N lane line calculation and determination units. This configuration has the effect of improving resistance to accuracy degradation or failure of each sensor.

[0102] 16, observation data output from an Nth sensor 20N (N is an integer from 1 to NS) is used as an input. Here, the Nth sensor 20N may be of any type as long as it has a function of acquiring the relative positional relationship between the target vehicle 1 and the lane markings, similar to the first sensor 201 and the second sensor 202 shown in the first embodiment.

[0103] The Nth lane line calculation / determination unit 10N calculates the distance to the lane line based on the observation data from the Nth sensor, and determines whether the target vehicle 1 has crossed the lane line based on the calculated distance. The calculated distance and the determination result are output to the traveling lane matching unit 113. Furthermore, lane change operation information from the traveling lane change operation information acquisition unit 213 (not shown) may be added as an input.

[0104] The driving lane matching unit 113a matches the calculated distances based on the outputs from the N lane line calculation and determination units so that the crossing time of the target vehicle 1 matches and the driving lane in which the target vehicle 1 is traveling matches, or outputs an inconsistent distance to the position estimation unit 114a.

[0105] Whether or not to match the calculated distances is determined in the traveling section matching unit 113a. The position estimation unit 114a calculates an estimated position of the target vehicle 1 from the distances calculated from the observation data of the first sensor to the Nth sensor and the matched distance in response to the output from the traveling section matching unit 113a.

[0106] <Processing by vehicle position estimation device> Fig. 17 is a flowchart showing the processing of the vehicle position estimation device 100b according to the fourth embodiment. The processing of the flowchart in Fig. 17 is executed at predetermined time intervals (for example, every 10 ms). The processing of the flowchart in Fig. 17 may be executed not at predetermined time intervals but every time the vehicle travels a predetermined distance, every time a sensor obtains new information, or in response to an event such as an external instruction.

[0107] In step ST601 of FIG. 17, an integer N (counter N) representing the Nth sensor is initialized to 1. In step ST602, the Nth lane line calculation determination unit 10N calculates the distance to the lane line based on the observation data of the Nth sensor 20N. Then, the Nth lane line calculation determination unit 10N determines whether the target vehicle 1 has crossed the lane line at the current time based on the calculated distance. This lane line crossing determination is realized by the same process as that described in step ST101 or step ST201 in the first embodiment. If it is determined that the lane line has been crossed, the Nth crossing flag is set.

[0108] In step ST603, it is determined whether the Nth traversal flag is set. If it is set (determination is YES), the process proceeds to step ST604. If the Nth traversal flag is not set (determination is NO), the process proceeds to step ST605.

[0109] In step ST604, the Nth lane line calculation determination unit stores the crossing time TN (N is an integer from 1 to NS) at which it is determined that the target vehicle 1 has crossed the lane line based on the calculated distance. The crossing time TN is a value that is not erased but is stored even after all the processing in FIG. 17 is completed. The initial value of TN is the observation start time of the Nth sensor. Following step ST604, in step ST610, the Nth crossing flag is cleared.

[0110] In step ST605, it is determined whether or not an integer N (counter N) representing the Nth sensor is equal to the total number of sensors NS. If this determination is true, the loop for sensor N is terminated and the process proceeds to step ST607. If this determination is false, the loop continues and the process proceeds to step ST606.

[0111] In step ST606, the integer N (counter N) indicating the Nth position is incremented by 1. After that, the process proceeds to step ST602, where the next Nth lane line calculation and determination unit performs calculation and determination.

[0112] In step ST607, the traveling lane matching unit 113a extracts all sensor numbers M that have been determined to have already crossed the lane marking. Here, M is an integer between 1 and NS. The extracted M may be 0 or multiple. Specifically, all sensor numbers M for which the difference between the current time and the crossing time TM is less than the matching duration TP1 are extracted. The sensor numbers M extracted in this step are used in the next step ST608.

[0113] In step ST608, the traveling lane matching unit 113a performs matching processing on the distance to the lane marking based on the observation data of the sensors other than the sensor number M. The traveling lane in which the target vehicle 1 is traveling can be matched based on the observation data of the sensors other than the sensor number M. Here, the sensor number M is all the sensor numbers M extracted in step ST608. The distance matching is the same as the processing described in step ST401 and step ST402 of FIG. 8 according to the first embodiment. The distance to be matched may be a representative value of the distances calculated using the observation data of the sensor number M, or a mode thereof, or an average value thereof.

[0114] In step ST609, the position estimation unit 114a estimates the position of the target vehicle 1 by using the distance calculated by using the observation data of each sensor that has been matched or not matched in step ST608. This process is similar to the process described in step ST501 of Fig. 8 according to the first embodiment. The process of the position estimation unit 114a can use existing sensor fusion technology.

[0115] In the example of Fig. 17, the integer N is incremented by 1 from 1 to NS. However, the increase or decrease of the integer N in Fig. 17 does not necessarily have to follow this procedure. It is sufficient that the integer N can take all values ​​from 1 to NS.

[0116] According to the vehicle position estimation device 100b according to the fourth embodiment configured as described above, even when observation data from N sensors are used, it is possible to suppress a decrease in accuracy of position estimation when the target vehicle 1 changes lanes. Furthermore, since the position of the target vehicle 1 is calculated based on observation data from N sensors, it is possible to obtain an effect of improving resistance to accuracy deterioration or failure of each sensor.

[0117] If the outputs of the two sensors, the first sensor 201 and the second sensor 202, and the calculation results and determination results of the first lane line calculation determination unit 101 and the second lane line calculation determination unit 102 are inconsistent, one of them may be malfunctioning. In this case, it may be difficult to determine which result to use. Even in such a case, if three or more sensors and three or more lane line calculation determination units are provided, reliable calculation results and determination results can be obtained by majority vote, and the reliability of the vehicle position estimation device 100b can be improved.

[0118] Although various exemplary embodiments and examples are described in this application, various features, aspects, and functions described in one or more embodiments are not limited to the application of a specific embodiment, but can be applied to the embodiments alone or in various combinations. Therefore, countless modifications not illustrated are expected within the scope of the technology disclosed in this specification. For example, the following are included: when at least one component is modified, added, or omitted, and further, when at least one component is extracted and combined with a component of another embodiment.

[0119] Various aspects of the present disclosure are summarized below as appendices.

[0120] (Appendix 1) a first demarcation line calculation and determination unit that detects a position of a demarcation line on a road surface, calculates a first distance between a vehicle and the demarcation line, and determines whether or not the vehicle has crossed the demarcation line based on the first distance; a second demarcation line calculation and determination unit that detects a position of the demarcation line on a road surface, calculates a second distance between the vehicle and the demarcation line, and determines whether or not the vehicle has crossed the demarcation line based on the second distance; A lane matching unit that matches at least one of the first distance or the second distance based on whether or not the vehicle crosses the lane line determined by the first lane line calculation determination unit and whether or not the vehicle crosses the lane line determined by the second lane line calculation determination unit; and A vehicle position estimation device comprising: a position estimation unit that estimates a position of the vehicle based on the first distance or the second distance aligned by the traveling section alignment unit. (Appendix 2) The first demarcation line calculation determination unit detects a position of the demarcation line based on a signal from a first sensor, The vehicle position estimation device according to claim 1, wherein the second lane line calculation determination unit detects the position of the lane line based on a signal from a second sensor. (Appendix 3) the first demarcation line calculation determination unit determines that the vehicle has crossed the demarcation line when the first distance changes by a greater amount than a predetermined crossing determination distance within a predetermined crossing determination time, or when the position of the demarcation line is switched from left to right, A vehicle position estimation device as described in Appendix 1 or 2, wherein the second lane line calculation determination unit determines that the vehicle has crossed the lane line when the second distance changes more than the crossing determination distance within the crossing determination time, or when the position of the lane line switches from left to right. (Appendix 4) A vehicle position estimation device described in any one of Appendices 1 to 3, wherein the driving lane matching unit starts matching at least one of the first distance or the second distance when either the first lane line calculation determination unit or the second lane line calculation determination unit determines that the vehicle has crossed the lane line. (Appendix 5) The vehicle position estimation device according to claim 4, wherein the travel section matching unit ends the distance matching when a predetermined matching duration time has elapsed after starting the distance matching. (Appendix 6) A vehicle position estimation device as described in any one of Appendices 1 to 5, wherein the traveling lane matching unit starts distance matching to match the distance calculated by the one lane line calculation determination unit with the distance calculated by the other lane line calculation determination unit when one of the first lane line calculation determination unit and the second lane line calculation determination unit determines that the vehicle has crossed the lane line earlier than the other. (Appendix 7) A vehicle position estimation device as described in Appendix 6, wherein the driving lane matching unit terminates matching of the distance calculated by the other lane line calculation determination unit when the other lane line calculation determination unit determines that the vehicle has crossed the lane line. (Appendix 8) A vehicle position estimation device as described in any one of Appendices 1 to 7, wherein the driving lane matching unit starts matching the first distance and the second distance based on the distance to a lane line other than the lane line when either the first lane line calculation determination unit or the second lane line calculation determination unit determines that the vehicle has crossed the lane line. (Appendix 9) the first demarcation line calculation determination unit executes at least one of: calculating a first right-side distance between the vehicle and a demarcation line on the right side of the vehicle and determining whether or not the vehicle has crossed the right-side demarcation line based on the first right-side distance; or calculating a first left-side distance between the vehicle and a demarcation line on the left side of the vehicle and determining whether or not the vehicle has crossed the left-side demarcation line based on the first left-side distance; the second demarcation line calculation determination unit executes at least one of: calculating a second right-side distance between the vehicle and a demarcation line on the right side of the vehicle and determining whether or not the vehicle has crossed the right-side demarcation line based on the second right-side distance; or calculating a second left-side distance between the vehicle and a demarcation line on the left side of the vehicle and determining whether or not the vehicle has crossed the left-side demarcation line based on the second left-side distance; The traveling lane matching unit is when either the first demarcation line calculation determination unit or the second demarcation line calculation determination unit determines that the vehicle has crossed the demarcation line from left to right, start at least one of matching based on the distance between the vehicle and the demarcation line adjacent to the right of the demarcation line crossed by the vehicle using the first right-side distance and the second right-side distance, or matching based on the distance between the vehicle and the demarcation line crossed by the vehicle using the first left-side distance and the second left-side distance, A vehicle position estimation device as described in Appendix 8, which, when either the first demarcation line calculation determination unit or the second demarcation line calculation determination unit determines that the vehicle has crossed the demarcation line from right to left, starts at least one of matching based on the first right-side distance and the second right-side distance between the vehicle and the demarcation line crossed by the vehicle, or matching based on the first left-side distance and the second left-side distance between the vehicle and the demarcation line adjacent to the left of the demarcation line crossed by the vehicle. (Appendix 10) A driving section change operation information acquisition unit that acquires driving section change operation information when a driving lane of the vehicle is changed, The first lane line calculation determination unit determines whether or not the vehicle has crossed the lane line based on the lane change operation information and the first distance, A vehicle position estimation device described in any one of Appendix 1 to 9, wherein the second lane line calculation determination unit determines whether or not the vehicle has crossed the lane line based on the driving lane change operation information and the second distance. (Appendix 11) one or more additional lane marking calculation and determination units that detect the position of the lane marking on a road surface, calculate a distance between the vehicle and the lane marking, and determine whether or not the vehicle is crossing the lane marking based on the distance; The lane alignment unit aligns at least one of the first distance, the second distance, and the distance calculated by the additional lane line calculation determination unit based on whether or not the vehicle has crossed the lane line determined by the first lane line calculation determination unit, whether or not the vehicle has crossed the lane line determined by the second lane line calculation determination unit, and whether or not the vehicle has crossed the lane line determined by the additional lane line calculation determination unit, A vehicle position estimation device according to any one of appendix 1 to 10, wherein the position estimation unit estimates the position of the vehicle based on the first distance, the second distance, or the distance aligned by the driving section alignment unit. [Explanation of symbols]

[0121] 1 vehicle, 100, 100a, 100b vehicle position estimation device, 101, 101a first lane line calculation and determination unit, 102, 102a second lane line calculation and determination unit, 10N Nth lane line calculation and determination unit, 113, 113a travel lane matching unit, 114, 114a position estimation unit, 201 first sensor, 202 second sensor, 20N Nth sensor, 213 travel lane change operation information acquisition unit

Claims

1. a first demarcation line calculation and determination unit that detects a position of a demarcation line on a road surface, calculates a first distance between a vehicle and the demarcation line, and determines whether or not the vehicle has crossed the demarcation line based on the first distance; a second demarcation line calculation and determination unit that detects a position of the demarcation line on a road surface, calculates a second distance between the vehicle and the demarcation line, and determines whether or not the vehicle has crossed the demarcation line based on the second distance; A lane matching unit that matches at least one of the first distance or the second distance based on whether or not the vehicle crosses the lane line determined by the first lane line calculation determination unit and whether or not the vehicle crosses the lane line determined by the second lane line calculation determination unit; and A vehicle position estimation device comprising: a position estimation unit that estimates a position of the vehicle based on the first distance or the second distance aligned by the traveling section alignment unit.

2. The first demarcation line calculation determination unit detects a position of the demarcation line based on a signal from a first sensor, The vehicle position estimation device according to claim 1 , wherein the second lane line calculation / determination unit detects the position of the lane line based on a signal from a second sensor.

3. the first demarcation line calculation determination unit determines that the vehicle has crossed the demarcation line when the first distance changes by a greater amount than a predetermined crossing determination distance within a predetermined crossing determination time, or when the position of the demarcation line is switched from left to right, The vehicle position estimation device of claim 1, wherein the second marking line calculation determination unit determines that the vehicle has crossed the marking line when the second distance changes more than the crossing determination distance within the crossing determination time, or when the position of the marking line changes from left to right.

4. The vehicle position estimation device of claim 1, wherein the driving lane matching unit starts matching at least one of the first distance or the second distance when either the first lane line calculation determination unit or the second lane line calculation determination unit determines that the vehicle has crossed the lane line.

5. The vehicle position estimation device according to claim 4 , wherein the travel section matching unit ends the distance matching when a predetermined matching duration time has elapsed after starting the distance matching.

6. The vehicle position estimation device of claim 1, wherein the driving lane matching unit starts distance matching to match the distance calculated by the one lane line calculation determination unit with the distance calculated by the other lane line calculation determination unit when one of the first lane line calculation determination unit and the second lane line calculation determination unit determines that the vehicle has crossed the lane line earlier than the other.

7. The vehicle position estimation device according to claim 6, wherein the lane matching unit terminates matching of the distance calculated by the other lane line calculation determination unit when the other lane line calculation determination unit determines that the vehicle has crossed the lane line.

8. The vehicle position estimation device of claim 1, wherein the driving lane matching unit starts matching the first distance and the second distance based on the distance to a lane line other than the lane line when either the first lane line calculation determination unit or the second lane line calculation determination unit determines that the vehicle has crossed the lane line.

9. the first demarcation line calculation determination unit executes at least one of: calculating a first right-side distance between the vehicle and a demarcation line on the right side of the vehicle and determining whether or not the vehicle has crossed the right-side demarcation line based on the first right-side distance; or calculating a first left-side distance between the vehicle and a demarcation line on the left side of the vehicle and determining whether or not the vehicle has crossed the left-side demarcation line based on the first left-side distance; the second demarcation line calculation determination unit executes at least one of: calculating a second right-side distance between the vehicle and a demarcation line on the right side of the vehicle and determining whether or not the vehicle has crossed the right-side demarcation line based on the second right-side distance; or calculating a second left-side distance between the vehicle and a demarcation line on the left side of the vehicle and determining whether or not the vehicle has crossed the left-side demarcation line based on the second left-side distance; The traveling lane matching unit is when either the first demarcation line calculation determination unit or the second demarcation line calculation determination unit determines that the vehicle has crossed the demarcation line from left to right, start at least one of matching based on the distance between the vehicle and the demarcation line adjacent to the right of the demarcation line crossed by the vehicle using the first right-side distance and the second right-side distance, or matching based on the distance between the vehicle and the demarcation line crossed by the vehicle using the first left-side distance and the second left-side distance, The vehicle position estimation device of claim 8, wherein when either the first demarcation line calculation determination unit or the second demarcation line calculation determination unit determines that the vehicle has crossed the demarcation line from right to left, at least one of the following is started: matching based on the first right-side distance and the second right-side distance between the vehicle and the demarcation line crossed by the vehicle, or matching based on the first left-side distance and the second left-side distance between the vehicle and the demarcation line adjacent to the left of the demarcation line crossed by the vehicle.

10. A driving section change operation information acquisition unit that acquires driving section change operation information when a driving lane of the vehicle is changed, The first lane line calculation determination unit determines whether or not the vehicle has crossed the lane line based on the lane change operation information and the first distance, The vehicle position estimation device according to claim 1 , wherein the second lane line calculation determination unit determines whether or not the vehicle has crossed the lane line based on the lane change operation information and the second distance.

11. one or more additional lane marking calculation and determination units that detect the position of the lane marking on a road surface, calculate a distance between the vehicle and the lane marking, and determine whether or not the vehicle is crossing the lane marking based on the distance; The lane alignment unit aligns at least one of the first distance, the second distance, and the distance calculated by the additional lane line calculation determination unit based on whether or not the vehicle has crossed the lane line determined by the first lane line calculation determination unit, whether or not the vehicle has crossed the lane line determined by the second lane line calculation determination unit, and whether or not the vehicle has crossed the lane line determined by the additional lane line calculation determination unit, The vehicle position estimation device according to claim 1 , wherein the position estimation unit estimates the position of the vehicle based on the first distance, the second distance, or the distance aligned by the traveling section alignment unit.

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