Driving assistance device, driving assistance system, and driving assistance method

Abstract

The purpose of the present invention is to provide a technology capable of appropriate driving assistance by mapping vehicles while performing appropriate correction by consolidating the vehicles. This driving assistance device comprises: a first inter-vehicle communication means that receives the position of a second other vehicle; a second inter-vehicle communication means that receives the position of a third other vehicle; and a vehicle mapping means that generates mapping information by appropriately correcting positions including the position of the host vehicle, the position of a first other vehicle, the position of the second other vehicle, and the position of the third other vehicle by consolidation, and mapping the positions in a distinguishable manner onto road data including lanes.

Description

Driving assistance device, driving assistance system, and driving assistance method

[0001] The present disclosure relates to a driving assistance device, a driving assistance system, and a driving assistance method.

[0002] Various technologies have been proposed to enable drivers to drive their own vehicle safely and comfortably while avoiding accidents in various traffic conditions (e.g., Patent Documents 1 to 5). For example, autonomous driving assistance devices have been proposed that assist driving by using an adaptive cruise control (ACC) function, a lane keep assist (LKA) function, a lane change assist (LCA) function, and a function for adjusting the optical axis of headlights, etc.

[0003] To realize these functions, it is necessary to acquire the positions of other vehicles around the vehicle (the relative positions of other vehicles with respect to the vehicle) and the position of the vehicle (absolute position). Peripheral measurement using millimeter-wave radar, cameras, etc. is widely used as a sensing means for acquiring the positions (relative positions) of other vehicles around the vehicle. Navigation devices that update the position of the vehicle based on road data are widely used as a sensing means for acquiring the absolute position of the vehicle, but positioning devices that measure the position of the vehicle on a driving lane with high accuracy are becoming more common.

[0004] Factors that have made it possible to achieve high accuracy in positioning include, for example, the use of inexpensive GNSS receivers and GNSS antennas compatible with two frequencies (civilian L1 and L2C) of multi-GNSS (Global Navigation Satellite System) satellites, including GPS, GLONASS, Galileo, Beidou, and QZSS, and, in the case of Japan, the free distribution of positioning augmentation information for precise point positioning (PPP-RTK method) from quasi-zenith satellites. By using these, high-precision positioning of float and fixed solutions, which are positioning solutions used for surveying, can be utilized, making it possible to perform composite positioning including autonomous navigation using vehicle speed (wheel speed) pulses and an inertial measurement unit (IMU), thereby enabling highly accurate positioning of the vehicle's position.

[0005] In addition to the development of the autonomous driving assistance devices described above, development is also underway on cooperative driving assistance devices that use V2X (Vehicle to Everything) communication to obtain driving-related information and the positions of other vehicles, thereby improving the convenience and safety of the vehicle itself.

[0006] Japanese Patent No. 4214841 Japanese Patent Application Laid-Open No. 2015-118500 Japanese Patent Application Laid-Open No. 2011-204151 Japanese Patent No. 3639196 Japanese Patent No. 4859652

[0007] It is desirable to provide safer and more secure driving assistance by maintaining a safe distance from other vehicles traveling in blind spots (to the left and right sides and rear of the vehicle) around the vehicle, which are outside the measurement range of the surrounding detection sensor. One possible method for achieving this is to calculate the positional relationship between the vehicle and other vehicles around the vehicle from the positions (absolute positions) of each vehicle transmitted and received via vehicle-to-vehicle communication. However, because vehicle-to-vehicle communication is a one-to-one vehicle-to-vehicle communication, there is a need to prioritize and efficiently collect the positions of other vehicles around the vehicle that can communicate with the vehicle. Furthermore, while it is desirable for vehicles capable of vehicle-to-vehicle communication to be able to determine a highly accurate position (absolute position) that can identify the driving lane, currently widespread driving assistance devices often use low-accuracy positions updated on road data (road links), such as navigation devices. Furthermore, navigation devices in each vehicle often update their positions asynchronously. Therefore, there is a need to be able to appropriately recognize the positional relationship between each vehicle even when high-accuracy and low-accuracy positions coexist, or when positions at different times coexist.

[0008] Therefore, the present disclosure has been made in consideration of the above-mentioned problems, and aims to provide a technology that enables appropriate driving assistance by mapping each vehicle while appropriately adjusting it through appropriate consolidation and integration.

[0009] The driving assistance device according to the present disclosure includes a positioning means for locating the position of the host vehicle based on measurement data from an autonomous navigation sensor and satellite positioning data from satellite positioning; a periphery measurement sensor for measuring the position of a first other vehicle present within a predetermined range around the host vehicle; a first vehicle-to-vehicle communication means for transmitting and receiving the position of the host vehicle and the position of the second other vehicle between the host vehicle and a second other vehicle around the host vehicle; a second vehicle-to-vehicle communication means for transmitting and receiving the position of the first other vehicle measured by the periphery measurement sensor of the host vehicle and the position of a third other vehicle measured by the periphery measurement sensor of the second other vehicle between the host vehicle and the second other vehicle; and a vehicle mapping means for generating mapping information by appropriately correcting each position, including the position of the host vehicle, the position of the first other vehicle, the position of the second other vehicle, and the position of the third other vehicle, by consolidating and merging them, and by distinguishably mapping each position to road data including lanes.

[0010] According to the present disclosure, the mapping information is generated by appropriately correcting the positions of the host vehicle, the first other vehicle, the second other vehicle, and the third other vehicle through consolidation and by mapping the positions to road data including lanes in a distinguishable manner. With this configuration, the mapping information can be generated by appropriately correcting the positions of the vehicles through consolidation and by mapping the positions to provide appropriate driving assistance.

[0011] The objects, features, aspects and advantages of the present disclosure will become more apparent from the following detailed description and the accompanying drawings.

[0012] 1 is a block diagram showing the configuration of a driving assistance device according to a first embodiment. FIG. 2 is a diagram showing an example of the positions of other vehicles around a host vehicle. (a) and (b) are diagrams showing an example of the locations and measurement ranges of a stereo camera and a millimeter-wave radar. FIG. 3 is a block diagram showing the configuration of a host vehicle positioning means according to the first embodiment. FIG. 4 is a diagram for explaining a mismatch in measurement timing and a data output delay. FIG. 5 is a flowchart showing the processing of a driving assistance device according to the first embodiment. FIG. 6 is a flowchart showing the processing of a driving assistance device according to the first embodiment. (a) to (e) are diagrams showing an example of the processing of the driving assistance device. FIG. 7 is a flowchart showing the processing of a host vehicle positioning means according to the first embodiment. (a) to (d) are diagrams for explaining the operation of a driving assistance device according to a first modification of the first embodiment. (a) and (b) are diagrams for explaining the operation of a driving assistance device according to a second modification of the first embodiment. (a) to (c) are diagrams for explaining the operation of a driving assistance device according to a second modification of the first embodiment. (a) and (b) are diagrams for explaining the operation of a driving assistance device according to a third modification of the first embodiment. 10(a) to 10(c) are diagrams for explaining the operation of a driving assistance device according to a third modification of the first embodiment. FIG. 10(a) is a block diagram showing the configuration of a roadside device according to a second embodiment. FIG. 10(a) and 10(b) are diagrams for explaining the operation of a roadside device according to the second embodiment. FIG. 10(a) to 10(c) are diagrams for explaining a first roadside device and a second roadside device according to a second modification of the second embodiment. FIG. 10(a) is a block diagram showing the configuration of a first roadside device according to a second modification of the second embodiment. FIG. 10(c) is a flowchart showing the processing of the ...a) is a block diagram showing the hardware configuration of a driving assistance device according to another modification. FIG. 10(c) is a block diagram showing the hardware configuration of a driving assistance device according to another modification.

[0013] <First Embodiment> Fig. 1 is a block diagram showing the configuration of a driving assistance device according to the first embodiment. The driving assistance device in Fig. 1 is a device that assists in driving a host vehicle. In the first embodiment, the driving assistance device is mounted on the host vehicle and displays (notifies) the positions of other vehicles around the host vehicle to the driver and passengers of the host vehicle, but the present invention is not limited to this.

[0014] Fig. 2 is a diagram showing a situation during a traffic jam as an example of the positions of other vehicles around the subject vehicle. The example of Fig. 2 shows a communication range 51, which is the range of inter-vehicle communication performed by a driving assistance device of the subject vehicle 52. For inter-vehicle communication, a frequency band of 5.9 GHz is used, for example, and the radius of the communication range 51 is several tens of meters (for example, 30 meters). In the example of Fig. 2, there are approximately 24 other vehicles within the communication range 51.

[0015] The host vehicle periphery measurement sensor of the host vehicle 52 can measure the presence of other vehicles within measurement ranges 52p and 52q in front of the host vehicle 52 and the positions of the other vehicles (the relative positions of the other vehicles with respect to the host vehicle 52). On the other hand, the host vehicle periphery measurement sensor of the host vehicle 52 cannot grasp the presence and positions (relative positions) of other vehicles in blind spot ranges, which are ranges to the sides and rear of the host vehicle 52 outside the measurement ranges 52p and 52q.

[0016] Therefore, the driving assistance device according to the first embodiment is configured to prioritize vehicle-to-vehicle communication with other vehicles (other vehicles indicated by solid lines in FIG. 2 ) around the subject vehicle 52 and collect the positions of the other vehicles in order to grasp the presence and positions (relative positions) of the other vehicles. The driving assistance device is also configured to map the other vehicles around the subject vehicle 52 obtained from the subject vehicle surroundings measurement sensor and the vehicle-to-vehicle communication, and display (notify) the map to the driver.

[0017] 1 includes a host vehicle positioning means 10 serving as a positioning means, a stereo camera 11 serving as a periphery measurement sensor, a millimeter-wave radar 12 serving as a periphery measurement sensor, a vehicle mapping means 13, high-precision map data 14 serving as road data including lanes, a display means 15, six V2X-first communication means 16a, 16b, ..., 16f serving as first vehicle-to-vehicle communication means, and six V2X-second communication means 17a, 17b, ..., 17f serving as second vehicle-to-vehicle communication means. Note that these interfaces may be provided in the driving assistance device instead of the stereo camera 11, the millimeter-wave radar 12, the high-precision map data 14, and the display means 15.

[0018] Next, an overview of each component of the driving assistance device will be described. A vehicle positioning unit 10 measures the position of the vehicle. A stereo camera 11 and a millimeter-wave radar 12 measure the white lines ahead of the vehicle and the positions of other vehicles (the relative positions of the white lines and other vehicles to the vehicle). A vehicle mapping unit 13 generates mapping information by mapping the positions of the vehicle and other vehicles onto high-precision map data 14.

[0019] The high-precision map data 14 includes, for example, three-dimensional shape information for each lane, created with an absolute accuracy of less than 50 cm for a predetermined range of expressways, three-dimensional shape information for road shoulders, as well as information on their longitudinal and transverse gradients and road elevations, etc. The display means 15 displays the mapping information generated by the vehicle mapping means 13, such as a road image depicting the position of the vehicle and the positions of other vehicles.

[0020] The V2X-first communication means 16a to 16f and the V2X-second communication means 17a to 17f perform V2X (Vehicle to Everything) communication, which is wireless communication with various external devices, and the V2X communication includes V2V (Vehicle to Vehicle) communication, which is communication between vehicles. Note that V2X communication may also include V2N (Vehicle to Network) communication, which is paid mobile communication, and V2I (Vehicle to Infrastructure) communication, which is road-to-vehicle communication.

[0021] The V2X-first communication means 16a to 16f perform V2V communication in accordance with a communication protocol of a predetermined frequency band (e.g., 5.96 GHz band) to simultaneously transmit and receive common item messages between the vehicle and up to six other vehicles around the vehicle at a predetermined period.

[0022] The common item message transmitted by the host vehicle is a message related to the position of the host vehicle, and includes, for example, the host vehicle ID / license plate, time, host vehicle position, host vehicle direction, host vehicle speed, position type (positioning / MM), satellite positioning method (standalone positioning / precise standalone positioning / RTK / VRS), MM map type (road / lane), positioning error, etc. The other vehicle transmits a common item message in which the host vehicle is replaced with the other vehicle in the common item message transmitted by the host vehicle. This enables the V2X-first communication means 16a to 16f to transmit and receive the position of the host vehicle and the position of the second other vehicle between the host vehicle and a second other vehicle in the vicinity of the host vehicle.

[0023] The V2X-second communication means 17a to 17f perform V2V communication in which dedicated item messages are individually transmitted and received between the host vehicle and up to six other vehicles around the host vehicle in accordance with a communication protocol for a predetermined frequency band (e.g., 5.96 GHz band). The dedicated item message transmitted by the host vehicle includes, for example, the host vehicle ID, the other vehicle ID of the transmission destination, the time, the number N of other vehicle measurements around the host vehicle, the positions [0] to [N-1] of the other vehicles around the host vehicle, the number m of host vehicle periphery measurement sensors, and information about each of the m host vehicle periphery measurement sensors (periphery measurement ranges such as measurement center direction, measurement angle, and measurement distance). The other vehicles transmit dedicated item messages in which the term "host vehicle" in the dedicated item message transmitted by the host vehicle is replaced with "other vehicle." This enables the V2X-second communication means 17a to 17f to transmit and receive, between the host vehicle and a second other vehicle surrounding the host vehicle, the position of a first other vehicle measured by the perimeter measurement sensor of the host vehicle and the position of a third other vehicle measured by the perimeter measurement sensor of the second other vehicle.Furthermore, the V2X-second communication means 17a to 17f enables the host vehicle and the second other vehicle surrounding the host vehicle to transmit and receive, between the host vehicle and the second other vehicle surrounding the host vehicle, the first perimeter measurement range of the perimeter measurement sensor of the host vehicle and the second perimeter measurement range of the perimeter measurement sensor of the second other vehicle.

[0024] Next, V2V communication, i.e., vehicle-to-vehicle communication, will be described in detail. In V2V communication, each vehicle simultaneously transmits (broadcasts) common item messages and the like, so V2V communication is possible only between vehicles equipped with communication means using the same frequency (e.g., 5.96 GHz band), and V2V communication is not possible with other vehicles. However, even between vehicles capable of V2V communication, if multiple vehicles communicate simultaneously using the same frequency, there is a possibility that multiple interference will occur between the communications between the multiple vehicles, making it impossible to receive data from each vehicle.

[0025] Therefore, the V2X-first communication means 16a to 16f and the V2X-second communication means 17a to 17f employ a wireless access method called CSMA / CA (Carrier Sense Multiple Access with Collision Avoidance), which separates communications in a time-division manner, as a wireless access method to avoid multiple interference. In this method, before a communication means of one vehicle starts communication, the communication means of the one vehicle checks whether the frequency band it wants to use is being used by a vehicle other than the one vehicle (Carrier Sense). If the communication means of the one vehicle confirms that the frequency band is not being used, it accesses the frequency band, and if it confirms that the frequency band is being used, it waits for a certain period of time before starting communication (Collision Avoidance).

[0026] However, if there is only one available frequency in a situation where there are many other vehicles communicating with the vehicle in the vicinity of the vehicle, the waiting time until communication can be established will be long, and there is a possibility that the positions of other vehicles around the vehicle traveling at high speeds will not be collected sufficiently.

[0027] Therefore, the cooperative ADAS (Advanced Driver-Assistance Systems) disclosed herein is provided with a plurality of V2X-first communication means that use a plurality of frequencies that do not interfere with each other (for example, a plurality of channels shifted by predetermined frequencies from a center frequency of 5.96 GHz). This allows the driving assistance device to perform V2V communication simultaneously in a plurality of pairings.

[0028] In addition, in order to enable the host vehicle to efficiently obtain the position of a third other vehicle around the second other vehicle, a plurality of V2X-second communication means are provided separately from the V2X-first communication means for performing additional data communication individually with a second other vehicle (pairing target) with which the host vehicle wishes to communicate.

[0029] In the first embodiment, six V2X-first communication means and six V2X-second communication means are provided. With this configuration, efficient V2V communication can be achieved between two other vehicles around the host vehicle located in each of the host vehicle's travel lane and the adjacent lanes on the left and right of the lane (i.e., a total of three lanes), that is, between a total of six other vehicles around the host vehicle. However, this is not essential, and the number of each of the V2X-first communication means and the V2X-second communication means may be one.

[0030] 3(a) and 3(b) are diagrams showing an example of the locations and measurement ranges of the perimeter measurement sensors (the stereo camera 11 and the millimeter-wave radar 12 in the first embodiment). These diagrams show the measurement range 11p of the stereo camera 11 and the measurement range 12q of the millimeter-wave radar 12, and the measurement range 11p and the measurement range 12q correspond to the measurement range 52p and the measurement range 52q in FIG. 2, respectively.

[0031] In the examples of FIGS. 3( a) and 3(b), the stereo camera 11 is provided above the windshield, and the millimeter-wave radar 12 is provided in the center of the front bumper. The stereo camera 11 measures white lines, other vehicles, and the like within a measurement range 11p. The measurement range 11p of the stereo camera 11 in FIG. 3(b) is, for example, angled 40 degrees left and right with respect to the front of the host vehicle 52, and ranges up to 100 meters ahead from the host vehicle 52. The millimeter-wave radar 12 measures other vehicles and the like within a measurement range 12q. The measurement range 12q of the millimeter-wave radar 12 in FIG. 3(b) is, for example, angled 20 degrees left and right with respect to the front of the host vehicle 52, and ranges up to 200 meters ahead from the host vehicle 52. Note that in the first embodiment, in order to prevent an increase in the price of the driving assistance device, measurement is limited to the area ahead of the host vehicle, which is required for an autonomous ADAS.

[0032] Next, we will explain the performance of the stereo camera 11 and the millimeter-wave radar 12. The stereo camera 11 measures the three-dimensional position, size, and shape of the boundary portions (areas where light and dark change) of obstacles such as other vehicles and pedestrians, and road markers such as white and yellow lines, based on the difference (parallax) between the left and right cameras when capturing images of those obstacles, and also measures the distance between the stereo camera 11 and the white lines (yellow lines) in the left-right direction.

[0033] The stereo camera 11 can detect the movement of an obstacle even if the obstacle moves across the detection direction. However, there are performance limitations, such as inability to measure when the windshield in front of the stereo camera 11 lens is dirty or fogged, in bad weather (heavy rain) or backlight, or at night or in a tunnel with the vehicle's lights off. In addition, because the measurement angle of the stereo camera 11 is relatively wide, the stereo camera 11 can measure other vehicles ahead traveling in adjacent lanes on the left and right of the driving lane, but the measurement distance of the stereo camera 11 is relatively short.

[0034] The millimeter-wave radar 12 detects the distance between the millimeter-wave radar 12 and an obstacle when millimeter waves (electromagnetic waves) transmitted at a predetermined detection angle are reflected by the obstacle and returned. The millimeter-wave radar 12 has excellent long-distance distance measurement performance and can ensure distance measurement performance regardless of sunlight conditions, brightness, or weather (rain, fog). On the other hand, the millimeter-wave radar 12 has performance limitations in that it has difficulty detecting obstacles with low reflectivity and cannot detect the movement of obstacles that cross the radar's detection direction. The millimeter-wave radar 12 has a relatively long measurement range and can therefore detect other vehicles at a distance that cannot be measured by the stereo camera 11, but the measurement angle of the millimeter-wave radar 12 is relatively narrow.

[0035] As described above, the stereo camera 11 and the millimeter-wave radar 12 have different performance limits. In order to prevent a situation in which the area ahead of the host vehicle cannot be measured due to the performance limits, in the first embodiment, a combination of the stereo camera 11 and the millimeter-wave radar 12 is used as a perimeter measurement sensor. This perimeter measurement sensor measures the position (relative position) of a first other vehicle that is present within a predetermined range around the host vehicle. Note that a perimeter measurement sensor similar to the perimeter measurement sensor described above is also provided on the second vehicle.

[0036] Fig. 4 is a block diagram showing the configuration of the vehicle positioning means 10 shown in Fig. 1. The vehicle positioning means 10 includes a GNSS receiver 100 including a GNSS antenna, a positioning augmentation signal receiver 101 including a GNSS antenna, a GNSS data acquisition means 102, a satellite positioning means 103, a speed sensor 104, an angular velocity sensor 105, a sensor data acquisition means 106, an autonomous navigation means 107, a data synchronization means 108, and a composite positioning means 109.

[0037] As will be described below, the host vehicle positioning means 10 in Fig. 4 is compatible with a satellite positioning method (precise positioning) that accurately determines the position of the host vehicle, and determines the position of the host vehicle based on measurement data from an autonomous navigation sensor and satellite positioning data from satellite positioning. This enables the host vehicle positioning means 10 to update the position of the host vehicle within the driving lane. The host vehicle positioning means 10 in Fig. 4 will be described below, but the host vehicle positioning means 10 according to the first embodiment is not limited to the configuration shown in Fig. 4.

[0038] The GNSS receiver 100, the positioning augmentation signal receiver 101, the GNSS data acquisition means 102, and the satellite positioning means 103 are means for performing satellite positioning.

[0039] The GNSS receiver 100 is located above the vehicle and receives radio signals (e.g., two frequencies, L1 signal and L2C signal) in a predetermined frequency band broadcast from multiple GNSS satellites, including at least GPS satellites. Based on the radio signals, the GNSS receiver 100 serially outputs time data, observation data such as pseudorange, carrier phase, and Doppler shift frequency for each satellite signal, and orbital data (broadcast almanac) required for calculating the satellite's position. Based on the radio signals, the GNSS receiver 100 also outputs a PPS (pulse per second) signal synchronized with the satellite positioning time system as a hardware signal for each positioning cycle.

[0040] In the case of Japan, the positioning augmentation signal receiver 101 receives a PPP-RTK (Precise Point Positioning - Real Time Kinematic) positioning augmentation signal (e.g., an L6 signal) broadcast to the ground by a quasi-zenith satellite using a GNSS antenna, and outputs the positioning augmentation data serially.

[0041] The GNSS data acquisition means 102 acquires data that is serially output at a predetermined cycle from each of the GNSS receiver 100 and the positioning augmentation signal receiver 101 .

[0042] The satellite positioning means 103 determines the vehicle's position (standalone positioning solution) and the GNSS receiver's built-in clock error using the time data included in the data acquired by the GNSS data acquisition means 102 and the observation data and orbit data of the satellites used for stand-alone positioning. The satellite positioning means 103 also determines the vehicle's position (positioning solutions such as float solutions and fixed solutions) and carrier phase bias using the positioning augmentation data included in the acquired data and the observation data of the satellites that are the target of the positioning augmentation data, and predicts the positioning error of each positioning solution of the satellite positioning. These predictions can be made using, for example, the predictions disclosed in Japanese Patent No. 7475547. In the example of FIG. 4 , the positioning result of the satellite positioning means 103 corresponds to satellite positioning data obtained by satellite positioning, and includes, for example, the observation values ​​of the satellites used for positioning, the positioning augmentation data, the stand-alone positioning solution, the float solution, the fixed solution, the GNSS receiver's built-in clock error, and the predicted positioning error.

[0043] The speed sensor 104, angular velocity sensor 105, sensor data acquisition means 106, and autonomous navigation means 107 are provided so that the vehicle position measurement means 10 can update the position of the vehicle by autonomous navigation even in a radio wave blocking section. In the example of Fig. 4, the outputs of the speed sensor 104 and angular velocity sensor 105 correspond to measurement data obtained by the autonomous navigation sensors.

[0044] The speed sensor 104 outputs a pulse signal corresponding to the distance traveled by the vehicle. The angular velocity sensor 105 outputs an angular velocity (yaw rate) [dps] with at least the vertical direction of the sensor housing as the sensor detection axis. However, although the angular velocity sensor 105 should normally output 0 [dps] when traveling straight, if the zero point is not corrected, it will output a yaw rate other than 0 [dps] due to an error. Note that this zero point error occurs because the zero point fluctuates due to temperature drift, etc. The output of the angular velocity sensor 105 when traveling straight, i.e., the zero point of the angular velocity sensor when traveling straight, is corrected by the autonomous navigation means 107, which will be described later.

[0045] The sensor data acquisition means 106 acquires the outputs of the velocity sensor 104 and the angular velocity sensor 105 as acquired information at predetermined intervals.

[0046] The autonomous navigation means 107 generates current autonomous navigation data by adding to the previous autonomous navigation data a movement vector based on the information acquired by the sensor data acquisition means 106. The autonomous navigation data includes, for example, the position, speed, movement distance, direction, yaw angle, etc. of the host vehicle.

[0047] The data synchronization means 108 interpolates the autonomous navigation data, for example, using software, so that the satellite positioning data from the satellite positioning means 103 and the autonomous navigation data from the autonomous navigation means 107 are synchronized based on the time of the PPS signal from the GNSS receiver 100.

[0048] The composite positioning means 109 performs composite positioning using the satellite positioning data and the autonomous navigation data interpolated by the data synchronization means 108. For example, the composite positioning means 109 predicts an error in the interpolated autonomous navigation data based on the positioning result and predicted positioning error included in the satellite positioning data, and corrects the position, speed, and direction of the host vehicle included in the autonomous navigation data.

[0049] The autonomous navigation means 107 corrects the SF (Scale Factor) [m / pulse] based on the results obtained by the composite positioning means 109. SF is a value for calculating the travel distance and speed from the number of pulses output by the speed sensor 104. The autonomous navigation means 107 also corrects the zero point of the yaw rate [dps] output by the angular velocity sensor 105 based on the results obtained by the composite positioning means 109. The corrections to the SF and yaw rate are reflected in the movement vector, and are therefore also reflected in the autonomous navigation data generated from the movement vector.

[0050] FIG. 5 is a diagram for explaining a mismatch in measurement timing between the autonomous navigation data and the satellite positioning data and a data output delay.

[0051] Generally, the processors of the vehicle positioning means 10 excluding the GNSS receiver 100 and the GNSS receiver 100 each use separate oscillators (such as a TCXO / temperature-compensated crystal oscillator) to generate the timing for periodically performing their respective processes. The GNSS receiver 100 observes satellite radio waves at a positioning cycle (epoch) synchronized with the time system of the satellite system to perform positioning calculations, and outputs observation data (raw data), positioning results, and other data as appropriate via a serial I / F. However, the number of observation data from satellites used in positioning calculations, the positioning time (convergence calculation time), and the data output time vary depending on the satellite radio wave reception environment.

[0052] In contrast, the sensor data acquisition means 106 acquires the outputs (sensor data) of the velocity sensor 104 and the angular velocity sensor 105 at a predetermined cycle that is asynchronous with the time system of the satellite positioning. As a result, the autonomous navigation data and the satellite positioning data become asynchronous. For this reason, even if composite positioning is performed using the satellite positioning data received with a delay from the update cycle of the vehicle's position (sensor data acquisition cycle) and the autonomous navigation data that is not delayed from the update cycle, high-precision positioning cannot be achieved.

[0053] In response to this, the data synchronization means 108 interpolates the autonomous navigation data using software so that the satellite positioning data and the autonomous navigation data are synchronized based on the time of the PPS signal from the GNSS receiver 100. This allows the combined positioning means 109, i.e., the vehicle positioning means 10, to perform combined positioning that can obtain the vehicle's position with high accuracy. Note that the interpolation of the autonomous navigation data can be performed using, for example, the interpolation method disclosed in Japanese Patent No. 6929492.

[0054] For convenience in the following description, the position of the host vehicle measured by the host vehicle position measurement means 10, the position (relative position) of the first other vehicle measured by the periphery measurement sensor, the position of the second other vehicle obtained by the V2X-first communication means 16a to 16f, and the position of the third other vehicle obtained by the V2X-second communication means 17a to 17f will be referred to as each position. The vehicle mapping means 13 in FIG. 1 generates mapping information by appropriately correcting each position through consolidation and by mapping each position in a distinguishable manner on the high-precision map data 14. In the mapping information generated by the vehicle mapping means 13, the positions of the host vehicle, the first other vehicle, the second other vehicle, and the third other vehicle are distinguishable.

[0055] The display means 15 displays the mapping information. The vehicle mapping means 13 checks whether the third other vehicle includes the subject vehicle, and based on the result of the check, changes the display of the second other vehicle and the third other vehicle in the mapping information displayed on the display means 15. The mapping information generated by the vehicle mapping means 13 will be described in detail later.

[0056] <Operation> Fig. 6 is a flowchart showing main processing (i.e., vehicle mapping processing) of the driving assistance device according to the first embodiment. Fig. 7 is a flowchart showing sub-processing (i.e., common item message reception interrupt processing) of the driving assistance device according to the first embodiment. Fig. 8 is a flowchart showing sub-processing (i.e., dedicated item message reception interrupt processing) of the driving assistance device according to the first embodiment. Figs. 9(a) to 9(e) are diagrams showing an example of processing of the driving assistance device. Note that the arrows in Fig. 9(a) and the like indicate that each vehicle travels from left to right.

[0057] In the following description, it is assumed that the satellite positioning of the other vehicle corresponds to high-precision positioning such as the PPP-RTK method, which is capable of determining the position of the other vehicle in the driving lane, similar to the satellite positioning of the own vehicle. Furthermore, it is assumed that the positioning time, which is the time of the satellite positioning (composite positioning) of the other vehicle, is synchronized with the PPS signal of the satellite positioning and synchronized with the positioning time of the own vehicle, similar to the satellite positioning of the own vehicle. A case in which the positioning time of the own vehicle and the positioning time of the other vehicle are not synchronized will be described in Modification 2.

[0058] First, an overview of the processing in FIG. 6 will be described. The processing from step ST601 to step ST605 is processing for an autonomous ADAS. The processing for an autonomous ADAS mainly includes (1) positioning the position of the host vehicle, (2) measuring the positions (absolute positions or relative positions) of white lines around the host vehicle and other vehicles, and (3) mapping the host vehicle and the first other vehicle to the high-precision map data 14. The processing from step ST606 to step ST616 is processing for a cooperative ADAS. The processing for a cooperative ADAS mainly includes (1) V2V communication for transmitting and receiving the position of the host vehicle and the positions of other vehicles around the host vehicle, and (2) mapping the second other vehicle and the third other vehicle obtained by the V2V communication to the high-precision map data 14. The mapping information obtained by the processing in FIG. 6 is displayed (announced) on the display means 15.

[0059] First, in step ST601, the driving assistance device initializes data that needs to be initialized at predetermined intervals. In step ST602, the vehicle position measuring means 10 measures the position of the vehicle. This positioning will be described in detail later with reference to FIG. 10. In step ST603, the stereo camera 11 measures the white line ahead of the vehicle and the first other vehicle, and in step ST604, the millimeter-wave radar 12 measures the white line ahead of the vehicle and the first other vehicle. For this measurement, for example, the measurement disclosed in Japanese Patent No. 7475547 can be used.

[0060] In step ST605, the vehicle mapping means 13 maps the positions of the host vehicle and the first other vehicle in a distinguishable manner on the high-precision map data 14. As a result, as shown in Fig. 9(a), mapping information is generated and displayed in which the host vehicle 52 and one or more first other vehicles 53a, 53b are marked on a road marked with a travel road (lane), so that the driver and passengers can visually recognize the relative positions of these vehicles.

[0061] In step ST606, the driving assistance device checks whether the current time corresponds to a period in which the common item message is simultaneously transmitted (broadcast) to the vicinity of the vehicle by the six V2X-first communication means 16a to 16f. If it is determined that the current time corresponds to a period in which the common item message is simultaneously transmitted (broadcast) to the vicinity of the vehicle, the process proceeds to step ST607, and if it is determined that the current time does not correspond to a period in which the common item message is simultaneously transmitted, the process proceeds to step ST609.

[0062] In step ST607, the driving assistance device creates a common item message indicating the position of the vehicle and the like.

[0063] In step ST608, the driving assistance device broadcasts a common item message of the host vehicle to the vicinity of the host vehicle by any one of the V2X-first communication means 16a to 16f, using a frequency channel unused by the other vehicles. Note that in this specification, for example, "at least one of A, B, C, ..., and Z" means any one of all combinations of one or more types extracted from the group of A, B, C, ..., and Z. The second other vehicle similarly broadcasts a common item message to the vicinity of the second other vehicle. The common item message transmitted from the second other vehicle indicates the position of the second other vehicle, etc.

[0064] In step ST609, the driving assistance device determines whether or not at least one of the V2X-first communication means 16a to 16f has received a common item message from a second other vehicle of the host vehicle in the process of Fig. 7 that is performed in parallel with the process of Fig. 6. The process of Fig. 7 will be described later.

[0065] 9(b) shows a state in which the driving assistance device has received a common item message from second other vehicles 54a, 54b, 54c around the subject vehicle 52. If it is determined that the common item message has been received, the process proceeds to step ST610, and if it is determined that the common item message has not been received, the process proceeds to step ST614.

[0066] In step ST610, the driving assistance device searches for and determines a second other vehicle that should preferentially communicate one-to-one with any one of the V2X-second communication means 17a to 17f to obtain its position (dedicated item message), i.e., a second other vehicle that should be the individual communication destination. For example, based on the position and direction of the second other vehicle that received the common item message, the driving assistance device searches for a second other vehicle that is present within the blind spot of the surrounding measurement sensors (stereo camera 11 and millimeter-wave radar 12) of the host vehicle as the individual communication destination. Note that the direction of the second other vehicle may be used to narrow down the second other vehicles traveling on the same road as the host vehicle as the individual communication destination.

[0067] The driving assistance device preferentially determines, as the individual communication destination, a second other vehicle that is as close as possible to the host vehicle and whose location has been updated as recently as possible, among the searched second other vehicles. A vehicle ID may be used to search for and determine the individual communication destination. Note that the driving assistance device may also determine, as the individual communication destination, a second other vehicle that is present within the measurement range of the perimeter measurement sensor of the host vehicle and for which communication via any one of the V2X-second communication means 17a to 17f is on hold. If all vehicles are present within the measurement range of the perimeter measurement sensor of the host vehicle and no communication via the V2X-second communication means 17a to 17f is on hold, an individual communication destination does not need to be determined.

[0068] In step ST611, the driving assistance device determines whether or not an individual communication destination has been determined. If it is determined that an individual communication destination has been determined, the process proceeds to step ST612, and if it is determined that an individual communication destination has not been determined, the process proceeds to step ST614.

[0069] In step ST612, the driving assistance device creates a dedicated item message indicating the position of the first other vehicle around the subject vehicle, etc.

[0070] In step ST613, the driving assistance device establishes communication with the individual communication destination using the V2X-second communication means 17a to 17f through a procedure of first to third stages. First, in the procedure of the first stage, the driving assistance device (host vehicle) sequentially switches between the V2X-second communication means 17a to 17f that are not being used for communication and are in standby, and transmits an authentication request to the individual communication destination to confirm that the communication destination is a valid communication destination. In the procedure of the second stage, the individual communication destination that has received the authentication request returns an authentication response to the driving assistance device (host vehicle). In the procedure of the third stage, upon receiving the authentication response, the driving assistance device (host vehicle) determines that communication can be established with the individual communication destination using the V2X-second communication means of that frequency, and transmits a message indicating that authentication has been completed to the individual communication destination.

[0071] After communication is established between the driving assistance device and the individual communication destination, the driving assistance device transmits a dedicated item message for its own vehicle to the individual communication destination via any one of V2X-second communication means 17a to 17f using the frequency channel on which communication is established. Similarly, the individual communication destination also transmits a dedicated item message to the driving assistance device (own vehicle). The dedicated item message transmitted from the individual communication destination indicates the position of a third other vehicle around the second other vehicle measured by the second other vehicle, which is the individual communication destination.

[0072] In step ST614, the driving assistance device determines whether at least one of the V2X-first communication means 16a to 16f has received a common item message from the second other vehicle in the process of Figure 7 that is performed in parallel with the process of Figure 6. The driving assistance device also determines whether at least one of the V2X-second communication means 17a to 17f has received a dedicated item message from the second other vehicle in the process of Figure 8 that is performed in parallel with the process of Figure 6. The processes of Figures 7 and 8 will be described later.

[0073] 9(c) shows a state in which the second other vehicle 54a is determined as the individual communication destination, and the driving assistance device receives a dedicated item message from the second other vehicle 54a indicating the positions of third other vehicles 55a, 55b, and 55c around the second other vehicle 54a. Since the third other vehicle is a vehicle seen from the second other vehicle, as shown in FIG. 9(c), the subject vehicle 52 may be measured as the third other vehicle 55a.

[0074] If it is determined in step ST614 that at least one of the common item message and the dedicated item message has been received, the process proceeds to step ST615, otherwise the process in Fig. 6 ends. Note that the process in Fig. 6 is repeated as needed.

[0075] In step ST615, the vehicle mapping means 13 consolidates the positions of the vehicles based on at least one of the received common item message and the dedicated item message. For example, when the distance between one of the first other vehicle, the second other vehicle, and the third other vehicle and the other vehicle is equal to or less than a threshold, the vehicle mapping means 13 consolidates the one vehicle and the other vehicle into one vehicle.

[0076] For example, the vehicle mapping means 13 maps the first other vehicle 53a in FIG. 9(a) and the second other vehicle 54b in FIG. 9(b) to the other vehicle P in FIG. 9(d). ３ The vehicle mapping means 13 consolidates the host vehicle 52 in FIG. 9(a) and the third other vehicle 55a in FIG. 9(c) into the host vehicle 52 in FIG. 9(d). The vehicle mapping means 13 consolidates the first other vehicle 53b in FIG. 9(a) and the third other vehicle 55c in FIG. 9(c) into the other vehicle P in FIG. 9(d). ５ The vehicle mapping means 13 maps the second other vehicle 54a and the second other vehicle 54c in FIG. 9(b) to the other vehicle P ２ and other vehicles P ４ 9(c) is integrated with the third other vehicle 55b in FIG. 9(d). １ Consolidate into.

[0077] FIG. 9(e) shows the vehicle 52 and the other vehicle P in the examples of FIGS. 9(a) to 9(d). １ ~P ５ 10 is a diagram showing the measurement results of the other vehicle P ４ The existence of the second other vehicle 54a is confirmed only by the common item message, and therefore is marked with a △, which indicates a low reliability. ２ Since the existence of the vehicle P is confirmed by both the common item message and the dedicated item message, it is marked with a double circle, which indicates a high degree of reliability. ２ The measurement ranges 54ap and 54aq of the vehicle P ２ The reliability of the measurement is high.

[0078] The driving assistance device may determine the order in which to check the positions of other vehicles based on the result of the consolidation. The driving assistance device may check the positions of other vehicles in the order of the first other vehicle, the second other vehicle, and the third other vehicle, or may check the positions of other vehicles in order of increasing reliability or decreasing reliability. For example, when the result of FIG. 9( e) is obtained, the driving assistance device may check the positions of other vehicle P ３ , P ５Then, the position of the second other vehicle P ２ , P ３ Then, the third vehicle, other vehicle P １ , P ５ You may check the location of

[0079] In step ST616 of FIG. 6 , the vehicle mapping means 13 generates mapping information by mapping the positions of the second and third other vehicles in a distinguishable manner on the high-precision map data 14 on which the host vehicle and the first other vehicle were mapped in step ST605 based on the result of the consolidation. As described above, mapping information is generated in which each position appropriately corrected by the consolidation is mapped in a distinguishable manner. The processing of FIG. 6 then ends. The processing of FIG. 6 is repeated as needed. In the above description, the vehicle mapping means 13 appropriately corrects each position by the consolidation and, in parallel, maps each position in a distinguishable manner on the high-precision map data 14. However, the vehicle mapping means 13 may appropriately correct each position by the consolidation and, thereafter, map each position in a distinguishable manner on the high-precision map data 14.

[0080] 9(d), only the host vehicle 52 is marked with dot hatching, the first other vehicles 53a, 53b are marked with neither solid nor dotted circles, the second other vehicles 54a to 54c are marked with solid circles, and the third other vehicles 55a to 55c are marked with dotted circles, making it possible to distinguish between the positions of the host vehicle, the first other vehicle, the second other vehicle, and the third other vehicle. Note that the mapping information may also include mapping of the measurement range of each vehicle.

[0081] The mapping information generated as described above is displayed by the display means 15. That is, the positions of the host vehicle, the first other vehicle, the second other vehicle, and the third other vehicle in the mapping information are displayed in a distinguishable manner. This prevents, for example, the driver and passengers of the host vehicle from mistaking one vehicle obtained from each of the positioning, peripheral measurement, and wireless communication for three vehicles, taking into account the accuracy of the positioning, peripheral measurement, and wireless communication. Note that the mapping information in which the host vehicle, the first other vehicle, the second other vehicle, and the third other vehicle are distinguished may be used not only for display but also for, for example, autonomous driving.

[0082] Furthermore, in the first embodiment, the vehicle mapping means 13 checks whether the third other vehicle includes the subject vehicle, and based on the check result, changes the display of the second other vehicle and the third other vehicle in the mapping information displayed on the display means 15. For example, the vehicle mapping means 13 may change the display of the second other vehicle and the third other vehicle measured by the second other vehicle depending on whether it has been confirmed that the third other vehicle includes the subject vehicle, whether it has been confirmed that the third other vehicle does not include the subject vehicle, or whether it has been unable to confirm that the third other vehicle neither includes nor does include the subject vehicle.

[0083] 9(d), as an example, diagonal hatching is applied to the second other vehicle 54a that measured the third other vehicle 55a including the subject vehicle 52, and the third other vehicle 55b that was measured by the second other vehicle 54a. Also, the second other vehicle 54c, which could not be confirmed as the third other vehicle, is diagonally hatched in the opposite direction.

[0084] Next, the processing in FIG. 7 will be described. In step ST701, the driving assistance device receives a common item message transmitted from a second other vehicle at a predetermined cycle using the V2X-first communication means 16a to 16f, and stores the message for each vehicle ID. Then, the processing in FIG. 7 ends. When the second other vehicle checks an unused frequency by CSMA / CA and transmits data, that is, when the second other vehicle determines the frequency to use for communication, the processing in FIG. 7 becomes a passive processing for the own vehicle.

[0085] Next, the processing in Fig. 8 will be described. In step ST801, the driving assistance device determines whether authentication has been completed or whether a message indicating that authentication has been completed has been received from the second other vehicle. If it is determined that authentication has been completed, the processing proceeds to step ST802, and if it is determined that authentication has not been completed, the processing in Fig. 8 ends.

[0086] In step ST802, the driving assistance device stores the common item message from the second other vehicle for each vehicle ID using any one of the authenticated V2X-second communication means 17a to 17f. Then, the process in FIG. 8 ends.

[0087] Fig. 10 is a flowchart showing the process of the host vehicle positioning means 10 locating the host vehicle position in step ST602 in Fig. 6. The process from step ST1001 to step ST1011 corresponds to the process of the satellite positioning method (precise positioning) that measures the host vehicle position with high accuracy so that the host vehicle position can be updated within the travel lane.

[0088] In step ST1001, the vehicle positioning means 10 initializes positioning-related processing. In step ST1002, the autonomous navigation means 107 acquires the number of pulses, which is the output of the speed sensor 104, from the information acquired at predetermined intervals by the sensor data acquisition means 106. The autonomous navigation means 107 then multiplies the number of pulses by a scale factor (SF) [m / pulse] to determine the travel distance, and calculates the speed using a value obtained by passing the number of pulses at each predetermined interval through a low-pass filter.

[0089] In step ST1003, the autonomous navigation means 107 acquires the yaw rate [dps] without zero point correction, which is the output of the angular velocity sensor 105, from the information acquired at predetermined intervals by the sensor data acquisition means 106. Then, the autonomous navigation means 107 performs a zero point correction process on the yaw rate while the vehicle is stopped. For this correction process, for example, the correction processes disclosed in Japanese Patent Nos. 3137784 and 3751513 can be used. That is, the autonomous navigation means 107 determines whether the vehicle is stopped based on the travel distance, calculates the average value of the yaw rate without zero point correction, which is the output of the angular velocity sensor 105 while the vehicle is stopped, and corrects the yaw rate of the angular velocity sensor 105 so that the average value becomes zero.

[0090] In step ST1004, the autonomous navigation means 107 calculates the yaw angle from the yaw rate without or after zero point correction. In step ST1005, the autonomous navigation means 107 calculates a movement vector for each predetermined period based on the movement distance in step ST1002 and the yaw angle in step ST1004. The autonomous navigation means 107 then adds the movement vector to the previous autonomous navigation data (position, speed, and direction of the host vehicle) to time-update the autonomous navigation data. Note that the position of the host vehicle in the autonomous navigation data is the position of the host vehicle in DR (Dead Reckoning).

[0091] In step ST1006, the vehicle positioning means 10 determines whether or not GNSS reception has occurred. That is, the vehicle positioning means 10 determines whether or not the positioning dimension of the satellite positioning cycle has been measured. If it is determined that GNSS reception has occurred, the process proceeds to step ST1007, and if it is determined that GNSS reception has not occurred, the process of Fig. 10 ends. The process of Fig. 10 is repeated as needed.

[0092] In step ST1007, the satellite positioning means 103 performs satellite positioning based on the data acquired at a predetermined cycle by the GNSS data acquisition means 102. The data acquired by the GNSS data acquisition means 102 is data obtained by the GNSS receiver 100 and the positioning augmentation signal receiver 101 receiving radio waves from GNSS satellites and calculating their positions.

[0093] As an example of satellite positioning, as in the technology of Japanese Patent No. 4988028 and Japanese Patent No. 6482720, the satellite positioning means 103 may compare pseudoranges with Doppler shift frequencies or carrier phases and select satellites for which a pseudorange residual can be calculated as satellites to be used for stand-alone positioning. The satellite positioning means 103 may then use time data, observation data of the satellites used for stand-alone positioning, and orbit data to determine the vehicle's position (stand-alone positioning solution) and the GNSS receiver's built-in clock error. Then, as in the technology of Japanese Patent No. 7475547, for example, the satellite positioning means 103 may use observation data of satellites that are the target of the positioning augmentation data and the positioning augmentation data to determine the vehicle's position (float solution and fixed solution) and carrier phase bias, and predict the positioning error of each positioning solution of the satellite positioning.

[0094] In step ST1008, the data synchronization means 108 interpolates the autonomous navigation data so that the satellite positioning data of the satellite positioning means 103 and the autonomous navigation data of the autonomous navigation means 107 are synchronized based on the time of the PPS signal from the GNSS receiver 100. Note that the interpolation of the autonomous navigation data can be performed using, for example, the interpolation method disclosed in Japanese Patent No. 6929492.

[0095] In step ST1009, the composite positioning means 109 performs composite positioning using the satellite positioning data and the autonomous navigation data interpolated by the data synchronization means 108. For example, as in the techniques of Japanese Patent Nos. 5855249, 6482720, 6877854, and 6929492, the composite positioning means 109 may correct the position of the host vehicle for composite positioning using satellite positioning data (observation values ​​of satellites used for positioning, positioning augmentation data, and stand-alone positioning solutions). This allows the composite positioning means 109 to calculate composite positioning solutions that match the driving trajectory even in the presence of local radio wave shielding or multipath.

[0096] Furthermore, when precise point positioning using a positioning augmentation signal is performed, the composite positioning means 109 may correct the error included in the position of the host vehicle for composite positioning based on satellite positioning data (positioning errors between a float solution or a fixed solution and their predictions), as in the technology of Japanese Patent No. 7475547. This allows the composite positioning means 109 to update the position of the host vehicle within the driving lane.

[0097] In step ST1010, the autonomous navigation means 107 corrects SF [m / pulse], for example, as in the techniques of Japanese Patent No. 3321096 and Japanese Patent No. 3727489.

[0098] In step ST1011, the autonomous navigation means 107 performs a process of correcting a zero point error during travel for the yaw rate [dps] output from the angular velocity sensor 105. For example, as in the techniques of Japanese Patent Nos. 3321096 and 3727489, the autonomous navigation means 107 calculates the difference between the orientation of the host vehicle at an arbitrary time as an initial value, which is calculated by integrating the yaw angle from moment to moment, and the orientation of the host vehicle for combined positioning by the combined positioning means 109. Then, the autonomous navigation means 107 corrects the zero point of the yaw rate during travel based on the difference. Thereafter, the process of FIG. 10 ends. The process of FIG. 10 is repeated as needed.

[0099] In the first embodiment described above, the V2V communication required for cooperative ADAS has been described. However, as long as the process related to mapping of other vehicles around the vehicle is not impaired, the driving assistance device may appropriately delete or change data from the common item message and dedicated item message of V2V communication, or may appropriately add data to these messages. Furthermore, in order to comply with vehicle-to-vehicle communication that is expected to become more widespread in the future, the radio wave frequency, communication method, number of communication channels, one-to-N communication, and the like described in the first embodiment may be appropriately changed.

[0100] Furthermore, when there are multiple other vehicles engaging in one-to-one vehicle-to-vehicle communication within a communication range of radio waves for the one-to-one vehicle-to-vehicle communication, the driving assistance device performs one-to-one vehicle-to-vehicle communication with one of the multiple other vehicles that is as close to the vehicle as possible. However, this is not limited to this. For example, the standard specifications for vehicle-to-vehicle communication may specify inbound and outbound lanes, main lanes, side lanes, service areas, and parking areas on the same road of a highway. In such cases, the driving assistance device may select a vehicle with which to perform one-to-one vehicle-to-vehicle communication (i.e., an individual communication destination) from multiple other vehicles traveling on the same road section in the same direction as the vehicle, which can be determined from the standard specifications.

[0101] Summary of First Embodiment According to the driving assistance device of the first embodiment described above, the vehicle mapping means 13 generates mapping information by appropriately correcting each position, including the position of the host vehicle, the position of the first other vehicle, the position of the second other vehicle, and the position of the third other vehicle, by consolidating and integrating them, and by mapping each position on the high-precision map data in a manner that allows each position to be distinguished. With this configuration, for example, the driver and passengers of the host vehicle can be prevented from mistaking one vehicle obtained from each of the positioning, peripheral measurement, and wireless communication for three vehicles, taking into account the accuracy of the positioning, peripheral measurement, and wireless communication. In this way, the driving assistance device of the first embodiment can provide appropriate driving assistance by appropriately mapping each vehicle.

[0102] Furthermore, in the first embodiment, the vehicle mapping means 13 checks whether the third other vehicle includes the subject vehicle, and based on the check result, changes the display of the second other vehicle and the third other vehicle in the mapping information displayed on the display means 15. With this configuration, the driver and passengers of the subject vehicle can check the reliability of the presence of other vehicles.

[0103] <Modification 1> In the first embodiment, a case has been described in which a host vehicle and other vehicles around the host vehicle that perform vehicle-to-vehicle communication each perform high-precision positioning that allows the vehicle's position to be updated on a travel lane. In this modification 1, a case has been described in which the host vehicle and other vehicles around the host vehicle as a whole include vehicles capable of high-precision positioning and vehicles incapable of high-precision positioning, that is, a case in which vehicles capable of high-precision positioning and vehicles incapable of high-precision positioning are mixed. Below, a case will be described in which the positioning time of the host vehicle and the positioning time of the other vehicles are synchronized, and a vehicle that is incapable of high-precision positioning broadcasts a common item message including a satellite positioning method (single positioning) and an MM map type (road) via V2X-first communication means.

[0104] 11(a) illustrates a case where the host vehicle 52 is located in the middle of three lanes, and the host vehicle positioning means and periphery measurement sensor of the host vehicle 52 have acquired information indicating that a first other vehicle 53 is located ahead in the lane adjacent to the left of the host vehicle 52. FIG. 11(b) illustrates a case where the host vehicle 52 is located in the middle of the three lanes, and the V2X-first communication means and V2X-second communication means of the host vehicle 52 have acquired information indicating that a third other vehicle 55 measured by the second other vehicle 54 is located ahead in the lane adjacent to the right of the second other vehicle 54. Hereinafter, a case where the vehicle mapping means 13 of the host vehicle 52 corrects the first other vehicle 53 in FIG. 11(a) and the second other vehicle 54 in FIG. 11(b) by consolidation will be described.

[0105] 11(c) shows a case where high-precision positioning is possible for the host vehicle 52 but not for the second other vehicle 54. In this case, the vehicle mapping means 13 of the host vehicle 52 determines that the accuracy of the position of the first other vehicle 53 is higher than the accuracy of the position of the second other vehicle 54, and consolidates the position of the second other vehicle 54 in FIG. 11(b) with the position of the first other vehicle 53 in FIG. 11(a). Then, in accordance with this correction, the vehicle mapping means 13 of the host vehicle 52 corrects the position of the third other vehicle 55 by moving it to the adjacent lane on the left.

[0106] 11(d) shows a case where high-precision positioning is not possible for the host vehicle 52, but high-precision positioning is possible for the second other vehicle 54. In this case, the vehicle mapping means 13 of the host vehicle 52 determines that the accuracy of the position of the second other vehicle 54 is higher than the accuracy of the position of the first other vehicle 53, and consolidates the position of the first other vehicle 53 in FIG. 11(a) into the position of the second other vehicle 54 in FIG. 11(b). Then, in accordance with this correction, the vehicle mapping means 13 of the host vehicle 52 corrects the position of the host vehicle 52 by moving it to the adjacent lane to the right.

[0107] As described above, in the present modified example 1, the vehicle mapping means 13 identifies the position with the highest accuracy among the positions based on the position-related information, and corrects the other positions by consolidating them based on the identified position. The position-related information here includes, for example, at least one of the position type (satellite positioning, combined positioning, or map matching), satellite positioning method (point positioning, precise point positioning, RTK, or VRS), satellite positioning solution (point positioning solution, Float solution, or Fix solution), map type (road or lane), and positioning error.

[0108] Generally, the absolute position of a vehicle determined by high-precision positioning and the relative position measured by a perimeter measurement sensor are both highly accurate. Therefore, with the above configuration, it is possible to generate mapping information in which the positions of each vehicle are appropriately corrected by consolidation. This allows the driver of the vehicle to easily and accurately grasp the positions of each vehicle from the displayed mapping information, thereby enabling appropriate driving.

[0109] The vehicle mapping means 13 may generate an error for each position based on the correction amount at the time of consolidation and add the error to the mapping information. The error here corresponds, for example, to the difference between the position before correction and the position after correction. With this configuration, the driver of the host vehicle can easily and accurately grasp the error for each position of each vehicle from the displayed mapping information. Furthermore, the vehicle mapping means 13 may add at least one of the first perimeter measurement range of the perimeter measurement sensor of the host vehicle and the second perimeter measurement range of the second other vehicle to the mapping information. With this configuration, the driver of the host vehicle can easily and accurately grasp the perimeter measurement range from the displayed mapping information.

[0110] <Modification 2> In the first embodiment and modification 1, it has been described that the positioning time of the subject vehicle and the positioning time of the other vehicle are synchronized, but in the present modification 2, a case where they are not synchronized will be described. Note that the following first and second cases are assumed as cases where the positioning time of the subject vehicle and the positioning time of the other vehicle are not synchronized.

[0111] In the following, a case will be described in which the V2X-first communication means and the V2X-second communication means transmit and receive updated times for each position between the host vehicle and a second other vehicle. FIG. 12(a) is a diagram for explaining the first case. In the first case, the positioning time of the other vehicle received through vehicle-to-vehicle communication is different from the positioning time of the host vehicle. In the example of FIG. 12(a), the host vehicle P ０ When the surrounding measurement sensor of the host vehicle P does not measure other vehicles ahead of the host vehicle, ０ is V2X-first communication means to another vehicle P １ , P ２ and receives a common item message from another vehicle P via the V2X-second communication means. ２ From other vehicle P ３ In the example of FIG. 12(a), a dedicated item message indicating １ , P ２ , P ３ The positioning time of each is t+Δt １ , t-Δt ２ , t-Δt ２ and the host vehicle P ０This is different from the positioning time t.

[0112] In such a case, as shown in FIG. 12(b), the vehicle mapping means 13 calculates the vehicle speed V １ and the positioning time is Δt １ Other vehicles P are moving forward １ The position of V １ Δt １ Similarly, the vehicle mapping means 13 performs a correction to shift the vehicle forward by V ２ , V ３ and the positioning time is Δt ２ Other vehicle P is delayed by ２ , P ３ The position of V ２ Δt ２ , V ３ Δt ２ The correction is made by shifting it forward by just that much.

[0113] 13A and 13B are diagrams for explaining the second case. In FIG. 13A, the host vehicle P ０ The surrounding measurement sensor of the vehicle P ０ Other vehicle P ahead Ｂ In FIG. 13(b), the host vehicle P ０ Another vehicle P Ａ The surrounding measurement sensor of other vehicles P Ａ Other vehicle P ahead Ｃ This indicates that the vehicle P is the third other vehicle. ０ and other vehicles P Ａ ~P Ｃ The positioning times of the other vehicles P in FIG. Ｂ and the other vehicle P in FIG. Ｃ It is the same vehicle.

[0114] Nevertheless, the other vehicle P in FIG. Ｂ The position of the other vehicle P Ｃ ΔL ＢThe reason for this discrepancy is thought to be that even if the positioning time of the other vehicle received through vehicle-to-vehicle communication indicates the same time as the positioning time of the subject vehicle, the positioning time of the second other vehicle is actually different from the positioning time of the subject vehicle.

[0115] In such a case, the vehicle mapping means 13 determines that the cause of the positional deviation is the other vehicle P Ｃ 13(b) as shown in FIG. 13(c). Ａ The position of ΔL Ａ The vehicle mapping means 13 also corrects the other vehicle P Ｃ is other vehicle P Ｂ and other vehicle P Ｃ Other vehicle P Ｂ Consolidate into.

[0116] As described above, in the present second modification, the vehicle mapping means 13 checks whether there is a difference or error in the time at each location during consolidation, and if there is a difference or error in the time at each location, corrects at least one of the locations so that the time at at least one of the other locations is synchronized with the time at one of the locations. This configuration makes it possible to generate mapping information in which the positions of each vehicle are appropriately corrected through consolidation. This increases the reliability of the mapping information, allowing the driver of the vehicle to drive with greater peace of mind.

[0117] As in the first modification, the vehicle mapping means 13 may add an error in each position to the mapping information, or may add at least one of the first periphery measurement range of the periphery measurement sensor of the host vehicle and the second periphery measurement range of the second other vehicle to the mapping information. The error here corresponds to, for example, the difference between the position before correction and the position after correction. In the example of FIG. 12(b), the error is V １ Δt １ , V ２ Δt ２ , V ３ Δt ２In the example of FIG. 13(c), ΔL Ａ The periphery measurement range is the measurement range of the periphery measurement sensor. With this configuration, the driver of the vehicle can easily and accurately grasp the position error of each vehicle and the periphery measurement range from the displayed mapping information.

[0118] <Variation 3> In this variation 3, the vehicle mapping means 13 adds, to the mapping information as a blind spot range, an area that is not included in either the peripheral measurement range of the host vehicle (measurement range of the peripheral measurement sensor) or the peripheral measurement range of the second other vehicle (measurement range of the peripheral measurement sensor).

[0119] FIG. 14( a) shows measurement ranges 52p and 52q of the perimeter measurement sensors of the host vehicle 52. FIG. 14( b) shows the communication range 51 of the host vehicle 52 and the measurement ranges 52p and 52q of the perimeter measurement sensors of the host vehicle 52. If all other vehicles within the communication range 51 of vehicle-to-vehicle communication are capable of vehicle-to-vehicle communication, it is possible that the communication range 51 of the host vehicle 52 will not be a blind spot. However, because radio waves in the 5.9 GHz band have a strong tendency to travel in a straight line and are obstructed by large vehicles, the area of ​​the communication range 51 on the opposite side of the large vehicle from the host vehicle 52 may be a blind spot. Therefore, in the following description, the blind spot when there is no second other vehicle is assumed to be the area outside the hatched area in FIG. 14( b) (measurement ranges 52p and 52q), but is not limited to this.

[0120] FIG. 15A shows a case where another vehicle P, which is a standard vehicle, is located in front of the host vehicle 52 in the lane adjacent to the host vehicle 52 on the right side of the lane in which the host vehicle 52 is traveling. １ The periphery measurement sensor of the host vehicle 52 can measure the area behind the host vehicle 52 compared to the normal vehicle. １ The area surrounded by the thick line on the far side is not a blind spot area.

[0121] FIG. 15B shows a situation where another vehicle P, a large truck, is located in front of the host vehicle 52 in the lane adjacent to the host vehicle 52 on the right side and within the measurement ranges 52p and 52q of the periphery measurement sensor. １The surroundings measurement sensor of the host vehicle 52 cannot measure the area behind the large truck relative to the host vehicle 52. １ As described above, even when the communication range 51 of the vehicle-to-vehicle communication is used, this range is a blind spot.

[0122] FIG. 15C shows the other vehicle P ２ There is another vehicle P ２ The other vehicle P is a large truck within the measurement range 54p, 54q. １ In the range further back than the third vehicle, ３ In this case, the vehicle mapping means 13 calculates the distance between the measurement ranges 52p and 52q of the host vehicle 52 and the distance between the measurement ranges 52p and 52q of the other vehicle P ２ The range that is not included in either of the measurement ranges 54p and 54q is set as a blind spot range. １ The area further back is other vehicles P ２ Since the distances are within the measurement ranges 54p and 54q, they are not blind spots.

[0123] According to the third modification, mapping information that includes a blind spot range that can change depending on the surrounding vehicle can be displayed to the driver and passengers of the vehicle. This allows the driver of the vehicle to recognize that other vehicles may be present in the blind spot range that cannot be measured by the driving assistance device, and allows the driver to drive carefully.

[0124] <Variation 4> When there are many other vehicles around the host vehicle for which high-precision positioning is not possible or when there are many other vehicles whose satellite positioning time systems are asynchronous, the vehicle mapping means 13 may be unable to successfully consolidate the vehicles. In such a case, the vehicle mapping means 13 may generate mapping information so as to distinguishably display the positions of the consolidated vehicles from the positions of the vehicles that could not be consolidated. Alternatively, the vehicle mapping means 13 may generate mapping information so as to display the errors of the vehicles that could not be consolidated in a larger scale. With this configuration, the driver of the host vehicle can distinguishably display the positions of the vehicles that could not be consolidated, allowing the driver of the host vehicle to drive carefully.

[0125] <Embodiment 2> The driving assistance device according to embodiment 1 maps each vehicle by integrating the positions of each vehicle collected using the surrounding measurement sensors (the stereo camera 11 and the millimeter-wave radar 12) of the vehicle itself and vehicle-to-vehicle communication.

[0126] In contrast, a driving assistance system according to the second embodiment includes a driving assistance device and a roadside unit attached (for example, permanently or temporarily) to a specific section of road. The roadside unit generates (photographs) the traffic conditions of the specific section of road as road image data, edits the road image data, and transmits it to the driving assistance device via road-to-vehicle communication, so that the driver and passengers of the vehicle can easily recognize the traffic conditions of the specific section of road. The driving assistance device is capable of displaying, on the display means 15, the mapping information on which the road image data has been superimposed by superimposing the mapping information displayed on the display means 15 with the road image data transmitted from the roadside unit closest to the vehicle.

[0127] Fig. 16 is a block diagram showing the configuration of a roadside device in the driving assistance system according to Embodiment 2. The roadside device in Fig. 16 includes a GNSS receiver 21, an internal camera 22, an image editing means 23, a broadcast data editing means 24, and a V2X communication means 25.

[0128] The GNSS receiver 21 performs satellite positioning to acquire the time at which a road image was captured. The internal camera 22 captures images of traffic conditions on a specific section of road. When road image data of the specific section captured by the internal camera 22 includes an oblique image, the image editing means 23 edits the oblique image by trapezoidal correction to convert it into a planar image viewed from directly above the road.

[0129] The broadcast data editing means 24 generates a broadcast item message. The broadcast item message includes, for example, road image data that has been keystone corrected by the image editing means 23, a roadside device ID, the position of the roadside device, the time of shooting by the internal camera 22, and the coordinates of the four corners of the specific section (i.e., the four corners of the planar image). The V2X communication means 25 broadcasts the broadcast item message at a predetermined interval to one or more vehicles traveling on the specific section of road, in accordance with a communication protocol for a predetermined frequency band (5.9 GHz band) for road-to-vehicle communication.

[0130] Fig. 17 is a flowchart showing the processing of the roadside device according to the second embodiment. This processing is performed at predetermined intervals. Figs. 18(a) and 18(b) are diagrams for explaining the processing of the roadside device, and Fig. 18(a) shows a roadside device 71 installed on a road. As will be described below, in the processing from step ST1701 to step ST1705, the roadside device captures and edits road image data of a specific section at predetermined intervals, generates a broadcast item message, and transmits it to one or more vehicles traveling on the specific section of road.

[0131] In step ST1701, the GNSS receiver 21 performs satellite positioning and updates the image capture time, which is the observation time. In step ST1702, the internal camera 22 captures an image of the traffic conditions on a specific section of road as shown in Fig. 18(a) and stores road image data (oblique image) obtained by the image capture by the internal camera 22. In step ST1703, the image editing means 23 performs trapezoidal correction (homography coordinate transformation) on the road image data (oblique image) to convert it into a planar image viewed from directly above the road as shown in Fig. 18(b).

[0132] In step ST1704, the broadcast data editing means 24 generates a broadcast item message including the trapezoidally corrected road image data (planar image), the coordinates of the four corners, the shooting time, etc. In step ST1705, the V2X communication means 25 broadcasts the broadcast item message at a predetermined cycle to one or more vehicles traveling on a specific section of road, in accordance with a communication protocol of a predetermined frequency band for V2X communication.

[0133] Fig. 19 is a block diagram showing the configuration of a driving assistance device in a driving assistance system according to the second embodiment. The configuration of the driving assistance device in Fig. 19 is the same as the configuration of the driving assistance device in Fig. 1, with the addition of 2ch V2X-third communication means 18a, 18b for road-to-vehicle communication. According to the driving assistance device in Fig. 19, not only vehicle-to-vehicle communication but also road-to-vehicle communication with a roadside unit can be performed.

[0134] Note that the V2X-third communication means 18a, 18b use multiple frequencies (for example, two channels shifted by a predetermined frequency from a center frequency of 5.9 GHz) in the same way as the V2X-first communication means 16a to 16f and the V2X-second communication means 17a to 17f. The V2X-third communication means 18a, 18b employ the above-mentioned CSMA / CA as a wireless access scheme to avoid multiple interference.

[0135] Next, the processing of the driving assistance device according to the second embodiment that differs from the processing of the driving assistance device according to the first embodiment will be described.

[0136] When the V2X-third communication means 18a, 18b receive a broadcast item message from the nearest roadside device, they output the message to the vehicle mapping means 13. The vehicle mapping means 13 superimposes the received road image data (traffic conditions) on mapping information that is the mapping result of each vehicle, and the display means 15 displays the mapping information on which the road image data has been superimposed. Because the road image data is a planar image with coordinates assigned to the four corners, the vehicle mapping means 13 can easily superimpose position marks of each vehicle on the road image data by synchronizing the time.

[0137] Summary of Second Embodiment According to the driving assistance system of the second embodiment described above, the vehicle mapping means 13 superimposes the mapping information displayed on the display means 15 onto the road image data transmitted from the roadside device closest to the vehicle. With this configuration, the driver of the vehicle can easily check the mapping information and the road image data, allowing the driver to drive with greater peace of mind.

[0138] In addition, in the second embodiment, when the road image data of a specific section includes a perspective image, the roadside device performs trapezoidal correction on the perspective image to convert it into a planar image viewed from directly above the road. With this configuration, the driving assistance device can easily superimpose mapping information and road image data.

[0139] <Modification> In the second embodiment, a case where one roadside unit is installed on a specific section of road has been described. However, in a specific section of road with poor visibility as shown in FIG. 20( a), a single roadside unit may not be able to capture the entire section of road. Therefore, as shown in FIG. 20( b), a first roadside unit 71 a and a second roadside unit 71 b may be installed at two locations on the specific section of road. Furthermore, the first roadside unit 71 a and the second roadside unit 71 b may capture images of the traffic conditions on the specific section of road from different viewpoints and directions, and broadcast broadcast item messages to one or more vehicles traveling on the specific section of road at predetermined intervals.

[0140] Then, as shown in Figure 20 (c), the driving assistance device may superimpose the position marks of each vehicle on new road image data that is created by concatenating (combining) the multiple road image data that it has received, and the display means 15 may display the image obtained by the superposition.

[0141] 21 is a block diagram showing the configuration of the first road-side device 71a according to this modification. The configuration of the first road-side device 71a will be described below, but the configuration of the second road-side device 71b may be the same as the configuration of the first road-side device 71a.

[0142] The V2X communication means 25 of the first roadside device 71a receives the broadcast item message from the second roadside device 71b. The image editing means 23 of the first roadside device 71a generates new road image data by linking the road image data generated by the first roadside device 71a with the road image data included in the broadcast item message received from the second roadside device 71b. The broadcast data editing means 24 of the first roadside device 71a generates a broadcast item message for the new road image data, and the V2X communication means 25 of the first roadside device 71a broadcasts the broadcast item message at a predetermined interval to one or more vehicles traveling on a specific section of road. The other configuration of the first roadside device 71a according to this modification is the same as the configuration of FIG. 16 .

[0143] 22 and 23 are flowcharts showing the processing of the first road-side device 71a according to this modification. The processing of the first road-side device 71a will be described below, but the processing of the second road-side device 71b may be similar to the processing of the first road-side device 71a. Note that, since the processing of steps ST2201 to ST2205 in FIG. 22 is similar to the processing of steps ST1701 to ST1705 in FIG. 17, the following description will mainly focus on steps ST2206 to ST2209.

[0144] In step ST2206, the image editing means 23 of the first roadside device 71a determines whether or not it holds the broadcast item message from the second roadside device 71b. If it is determined that it holds the broadcast item message, the process proceeds to step ST2207, and if it is determined that it does not hold the broadcast item message, the process of FIG. 22 ends.

[0145] In step ST2207, the image editing means 23 of the first roadside unit 71a generates new road image data (one planar image) by combining the road image data generated by the first roadside unit 71a and the road image data included in the broadcast item message received from the second roadside unit 71b.

[0146] In step ST2208, the broadcast data editing means 24 of the first roadside device 71a generates a broadcast item message for the new road image data. In step ST2209, the V2X communication means 25 of the first roadside device 71a broadcasts the broadcast item message at a predetermined interval to one or more vehicles traveling on a specific section of road.

[0147] Next, a description will be given of the processing in Fig. 23. The processing in Fig. 23 is performed in parallel with the processing in Fig. 22.

[0148] In step S2301, the image editing means 23 of the first roadside device 71a determines whether or not a broadcast item message has been received from the second roadside device 71b. If it is determined that a broadcast item message has been received, the process proceeds to step ST2302, and if it is determined that a broadcast item message has not been received, the process of FIG. 23 ends.

[0149] In step ST2302, the image editing means 23 of the first roadside device 71a holds the broadcast item message from the second roadside device 71b, and then the process of FIG.

[0150] According to the present modified example, the first roadside device 71 a generates and transmits new road image data by combining the road image data generated by the first roadside device 71 a and the road image data received from the second roadside device 71 b. With this configuration, it is possible to capture the entire road in a specific section, even if the road is in a section with poor visibility.

[0151] <Other Modifications> The host vehicle positioning means, the periphery measurement sensor, the V2X-first communication means, the V2X-second communication means, and the vehicle mapping means described above will hereinafter be referred to as the "host vehicle positioning means, etc." The host vehicle positioning means, etc. are realized by a processing circuit 81 shown in FIG. That is, the processing circuit 81 includes a host vehicle positioning means for locating the position of the host vehicle based on measurement data from an autonomous navigation sensor and satellite positioning data from satellite positioning, a periphery measurement sensor for measuring the position of a first other vehicle present within a predetermined range around the host vehicle, a first V2X communication means for transmitting and receiving the position of the host vehicle and the position of the second other vehicle between the host vehicle and a second other vehicle around the host vehicle, a second V2X communication means for transmitting and receiving the position of the first other vehicle measured by the periphery measurement sensor of the host vehicle and the position of a third other vehicle measured by the periphery measurement sensor of the second other vehicle between the host vehicle and the second other vehicle, and a vehicle mapping means for generating mapping information by appropriately correcting each position including the position of the host vehicle, the position of the first other vehicle, the position of the second other vehicle, and the position of the third other vehicle by consolidating and integrating them, and by distinguishably mapping each position to road data including lanes. The processing circuit 81 may be implemented by dedicated hardware or a processor that executes a program stored in memory. Examples of processors include central processing units, processing units, arithmetic units, microprocessors, microcomputers, and DSPs (Digital Signal Processors).

[0152] When the processing circuit 81 is dedicated hardware, the processing circuit 81 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field Programmable Gate Array), or a combination thereof. The functions of each unit of the vehicle positioning means and the like may be realized by a circuit in which the processing circuits are distributed, or the functions of each unit may be realized together by a single processing circuit.

[0153] When the processing circuit 81 is a processor, the functions of the vehicle positioning means and the like are realized in combination with software and the like. The software and the like may include, for example, software, firmware, or software and firmware. The software and the like are written as programs and stored in a memory. As shown in FIG. 25 , the processor 82 applied to the processing circuit 81 realizes the functions of each unit by reading and executing programs stored in a memory 83. That is, the driving assistance device includes a memory 83 for storing a program that, when executed by the processing circuit 81, results in the following steps: determining the position of the host vehicle based on measurement data from an autonomous navigation sensor and satellite positioning data from satellite positioning, measuring the position of a first other vehicle present within a predetermined range around the host vehicle, transmitting and receiving the position of the host vehicle and the position of the second other vehicle between the host vehicle and a second other vehicle around the host vehicle, transmitting and receiving the position of the first other vehicle measured by the host vehicle and the position of a third other vehicle measured by the second other vehicle between the host vehicle and the second other vehicle, and generating mapping information by appropriately correcting and integrating each position including the position of the host vehicle, the position of the first other vehicle, the position of the second other vehicle, and the position of the third other vehicle, and mapping each position to road data including lanes in a distinguishable manner. In other words, this program can be said to cause a computer to execute the procedures and methods of the host vehicle position determining means, etc. Here, the memory 83 may be, for example, a non-volatile or volatile semiconductor memory such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EPROM (Erasable Programmable Read Only Memory), or an EEPROM (Electrically Erasable Programmable Read Only Memory), a HDD (Hard Disk Drive), a magnetic disk, a flexible disk, an optical disk, a compact disk, a mini disk, a DVD (Digital Versatile Disc), a drive device for any of these, or any storage medium to be used in the future.

[0154] The above describes a configuration in which each function of the vehicle position measuring means, etc. is realized either by hardware or software, etc. However, the present invention is not limited to this, and a configuration in which part of the vehicle position measuring means, etc. is realized by dedicated hardware and another part is realized by software, etc. For example, the function of the vehicle position measuring means can be realized by a processing circuit 81 as dedicated hardware, and the other functions can be realized by the processing circuit 81 as a processor 82 reading and executing programs stored in a memory 83.

[0155] As described above, the processing circuitry 81 can realize the above-described functions by hardware, software, or a combination of these.

[0156] The driving assistance device described above can also be applied to a driving assistance system constructed as a system by appropriately combining a vehicle device, a communication terminal, the functions of an application installed on at least one of the vehicle device and the communication terminal, and a server. The communication terminal includes, for example, a mobile phone, a smartphone, and a tablet. The functions or components of the driving assistance device described above may be distributed among the devices that construct the system, or may be centrally located in one of the devices.

[0157] In this disclosure, 'a' and 'an' mean one or more. Therefore, 'a', 'an', 'one or more', and 'at least one' can be used interchangeably.

[0158] It should be noted that the embodiments and modifications may be freely combined, and the embodiments and modifications may be modified or omitted as appropriate.

[0159] The above description is illustrative in all respects and is not restrictive. It is understood that countless variations not illustrated can be envisioned.

[0160] 10 Vehicle positioning means, 11 Stereo camera, 12 Millimeter wave radar, 13 Vehicle mapping means, 14 High precision map data, 15 Display means, 16a to 16f V2X-first communication means, 17a to 17f V2X-second communication means, 52 Vehicle, 53 First other vehicle, 54 Second other vehicle, 55 Third other vehicle, 71 Roadside unit, 71a First roadside unit, 71b Second roadside unit.

Claims

1. A driving assistance device comprising: a positioning means for locating a position of a vehicle based on measurement data from an autonomous navigation sensor and satellite positioning data from satellite positioning; a periphery measurement sensor for measuring the position of a first other vehicle present within a predetermined range around the vehicle; a first vehicle-to-vehicle communication means for transmitting and receiving the position of the vehicle and the position of the second other vehicle between the vehicle and a second other vehicle around the vehicle; a second vehicle-to-vehicle communication means for transmitting and receiving the position of the first other vehicle measured by the periphery measurement sensor of the vehicle and the position of a third other vehicle measured by the periphery measurement sensor of the second other vehicle between the vehicle and the second other vehicle; and a vehicle mapping means for generating mapping information by appropriately correcting each position, including the position of the vehicle, the position of the first other vehicle, the position of the second other vehicle, and the position of the third other vehicle, by consolidating and merging them, and by distinguishably mapping each of the positions on road data including lanes.

2. A driving assistance device as described in claim 1, further comprising a display means for displaying the mapping information, wherein the vehicle mapping means checks whether the third other vehicle includes the subject vehicle, and changes the display of the second other vehicle and the third other vehicle in the mapping information displayed by the display means based on the result of the check.

3. A driving assistance device as described in claim 1, wherein the first inter-vehicle communication means and the second inter-vehicle communication means transmit and receive position-related information, which is at least one of the position type, satellite positioning method, satellite positioning solution, map type, and positioning error, of each of the host vehicle and the second other vehicle, and the vehicle mapping means identifies the position with the highest accuracy among the positions based on the position-related information, and corrects other positions by consolidating them based on the identified position.

4. A driving assistance device according to claim 3, wherein the vehicle mapping means generates an error for each position based on a correction amount at the time of consolidation, and adds the error to the mapping information.

5. A driving assistance device as described in claim 1, wherein the first inter-vehicle communication means and the second inter-vehicle communication means transmit and receive updated times for each of the locations between the host vehicle and the second other vehicle, and the vehicle mapping means, when consolidating, checks whether there is a difference or error in the times for each of the locations, and if there is a difference or error in the times for each of the locations, corrects at least one of the locations so that the time for one of the locations is synchronized with the time for at least one of the other locations.

6. A driving assistance device as described in claim 1, wherein the second vehicle-to-vehicle communication means transmits and receives a first periphery measurement range of the periphery measurement sensor of the host vehicle and a second periphery measurement range of the periphery measurement sensor of the second other vehicle between the host vehicle and the second other vehicle, and the vehicle mapping means adds at least one of the first periphery measurement range and the second periphery measurement range to the mapping information.

7. A driving assistance device as described in claim 1, wherein the vehicle mapping means adds an area that is not included in either the surrounding measurement range of the subject vehicle or the surrounding measurement range of the second other vehicle to the mapping information as a blind spot area.

8. A driving assistance system comprising: a driving assistance device according to claim 1; and a roadside unit attached to a specific section of road, wherein the roadside unit generates and transmits road image data for the specific section; the driving assistance device further comprises display means for displaying the mapping information; and the vehicle mapping means superimposes the mapping information displayed on the display means on the road image data transmitted from the roadside unit closest to the vehicle.

9. A driving assistance system as described in claim 8, wherein, when the road image data includes an oblique image of the specific section, the roadside device performs trapezoid correction on the oblique image to convert it into a planar image, and transmits the trapezoid-corrected road image data, the coordinates of the four corners of the planar image, and the time the oblique image was taken.

10. A driving assistance system as described in claim 8, wherein the roadside devices include a first roadside device and a second roadside device attached to the road in the same specific section, and when the first roadside device receives the road image data generated by the second roadside device from the second roadside device, the first roadside device generates and transmits new road image data that combines the road image data generated by the first roadside device with the road image data received from the second roadside device.

11. A driving assistance method comprising: determining a position of a host vehicle based on measurement data from an autonomous navigation sensor and satellite positioning data from satellite positioning; measuring the position of a first other vehicle present in a predetermined range around the host vehicle; transmitting and receiving the position of the host vehicle and the position of the second other vehicle between the host vehicle and a second other vehicle around the host vehicle; transmitting and receiving the position of the first other vehicle measured by the host vehicle and the position of a third other vehicle measured by the second other vehicle between the host vehicle and the second other vehicle; appropriately correcting each position including the position of the host vehicle, the position of the first other vehicle, the position of the second other vehicle, and the position of the third other vehicle by consolidating and integrating them, and generating mapping information by distinguishably mapping each of the positions to road data including lanes.

Images