Driving assistance device

Abstract

Driving assistance device for performing driving assistance of a host vehicle based on signal cycle information relating to light color cycles of a traffic signal system at an intersection, wherein: If the signal cycle information is not available, the device estimates the signal cycle information based on environmental information regarding the intersection and performs driving assistance based on the estimated signal cycle information. the device includes a variety of estimation methods for estimating the signal cycle information and selects from the variety of estimation methods to be used for estimating the signal cycle information according to a scenario in which the signal cycle information is not available, the device selects a feasible service from driving assistance services according to the selected estimation method and scenario, and The device provides the selected service using signal cycle information estimated by the selected estimation method.

Description

BACKGROUND TECHNOLOGY

[0001] A conventional driver assistance device installed in a vehicle to assist a driver in driving a vehicle is known to be one that supports driving based on signal cycle information provided by a traffic light at an intersection. For example, JP 2008-299666A discloses a technique that determines, based on the distance to an intersection, the vehicle speed, and signal information provided by a traffic light, whether the host vehicle is in a dangerous driving condition and performs acceleration or deceleration control if the vehicle is in a dangerous driving condition. Similarly, JP 2006-48624A, JP 2009-9610A, and JP 2009-265837A disclose driver assistance techniques that use signal cycle information.

[0002] However, the conventional techniques described above assume that signal cycle information can be acquired, which means there is room for improvement in driver assistance for use when signal cycle information is unavailable.

[0003] The (subsequently published) German patent application DE 10 2011 004 425 A1 discloses a method for estimating the status of a traffic light system. The method detects that a vehicle is approaching a traffic light system. This can be done, for example, using a satellite-based navigation system. The method then checks whether the driver intends or is prepared to decelerate. Based on this, the status of the traffic light system is estimated. For example, if a driver's intention or readiness to decelerate is detected when approaching a traffic light, it can be assumed that the traffic light is emitting a red signal. Thus, the method allows the status of the traffic light system to be estimated without the traffic light system needing to have a transmitter for sending a corresponding radio signal.

[0004] Further state of the art is known from EP 1 481 837 B1 and DE 103 34 620 A1. SUMMARY OF THE INVENTION

[0005] In view of the foregoing, an object of the present invention is to provide a driving assistance device that is capable of adequately assisting driving even when signal cycle information is not available.

[0006] According to the invention, a driving assistance device is provided as defined in the independent patent claim, wherein advantageous embodiments and / or further developments of this are defined in the dependent patent claims.

[0007] According to the present disclosure, a driving assistance device is a driving assistance device for performing driving assistance of a host vehicle based on signal cycle information regarding a lighting cycle of a traffic signal at an intersection, wherein the driving assistance device is characterized in that, if the signal cycle information is not available, the device estimates the signal cycle information based on environmental information regarding the intersection and performs driving assistance based on the estimated signal cycle information.

[0008] The driving assistance device described above is preferably characterized in that the device comprises a plurality of estimation methods for estimating the signal cycle information and selects an estimation method used for estimating the signal cycle information from the plurality of estimation methods according to a scenario in which the signal cycle information is not available.

[0009] The driving assistance device described above is preferably characterized in that the device selects a deliverable service from services for driving assistance according to the selected estimation method and the scenario.

[0010] The driving assistance device described above is preferably characterized in that a case in which the signal cycle information is not available refers to a case in which a sending side of the signal cycle information does not send the signal cycle information.

[0011] The driving assistance device described above is preferably characterized in that a case in which the signal cycle information is not available refers to a case in which a receiving side of the signal cycle information does not receive the signal cycle information.

[0012] The driving assistance device described above is preferably characterized in that a case in which the signal cycle information is not available refers to a case in which an information processing load in the host vehicle is high and a reception processing of the signal cycle information is delayed.

[0013] The driving assistance device described above is preferably characterized in that the environmental information includes at least road information regarding the intersection, a presence status of other vehicles or pedestrians around the intersection, a remaining time until a signal type changeover time at the intersection, detected signal cycle information and / or a presence status of an emergency vehicle or a public vehicle around the intersection.

[0014] The driving assistance device described above is preferably characterized in that the vehicle determines, based on road information regarding the intersection, whether a route of the host vehicle is a main road or a side road, estimates signal cycle information as equivalent to a green traffic light when it is determined that the route is a main road, and estimates signal cycle information as equivalent to a red traffic light when it is determined that the route is a side road.

[0015] The driving assistance device described above is preferably characterized in that the device determines, based on the presence of other vehicles or pedestrians around the intersection, whether it is necessary for the host vehicle to stop at the intersection, estimates signal cycle information as equivalent to a green light signal when it is determined that it is not necessary for the vehicle to stop, and estimates signal cycle information as equivalent to a red light signal when it is determined that it is necessary for the vehicle to stop.

[0016] The driving assistance device described above is preferably characterized in that the device estimates signal cycle information based on a remaining time until a signal type switching time at the intersection.

[0017] The driving assistance device described above is preferably characterized in that the device estimates the signal cycle information based on the detected signal cycle information.

[0018] The driving assistance device described above is preferably characterized in that the device determines, based on a presence state of an emergency vehicle or a public vehicle around the intersection, whether a route of the host vehicle is a main road or a side road, estimates signal cycle information as equivalent to a green traffic light signal when it is determined that the route is a main road, and estimates signal cycle information as equivalent to a red traffic light signal when it is determined that the route is a side road. ADVANTAGEOUS EFFECTS OF THE INVENTION

[0019] The driving assistance device according to the present invention estimates signal cycle information based on environmental information regarding an intersection when the signal cycle information is unavailable. This makes it possible to provide a driving assistance service based on signal cycle information continuously without interruption, with the resulting effect that driving assistance can be performed appropriately even when signal cycle information is unavailable. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a block diagram showing a general configuration of a driving assistance device in an embodiment of the present invention. Fig. Figure 2 is a schematic representation showing an example of a road-vehicle communication configuration implemented by the driving assistance device in this embodiment. Fig. Figure 3 is a schematic representation showing solution 1-1, which is one of the signal cycle information estimation methods performed by the driving assistance device in this embodiment. Fig. Figure 4 is a schematic representation showing solution 1-4, which is one of the signal cycle information estimation methods performed by the driving assistance device in this embodiment. Fig. Figure 5 is a schematic representation showing solution 3-1, which is one of the signal cycle information estimation methods performed by the driving assistance device in this embodiment. Fig. Figure 6 is a representation that shows an example of the settings of scenario type in which signal cycle information is not sent, scenario determination condition for each scenario, selectable solutions and deliverable services, all of which are used in the signal cycle information estimation processing. Fig. Figure 7 is a representation that shows an example of the content of situations and means that are in the element "Scenario Determination Condition" in Fig. 6 are listed. Fig. Figure 8 is a representation that shows an example of the settings of scenario type in which signal cycle information is not received, scenario determination condition for each scenario, selectable solutions and deliverable services, all of which are used in the signal cycle information estimation processing. Fig. Figure 9 is a representation that shows an example of the content of situations and means that are in the element "Scenario Determination Condition" in Fig. 8 are listed. Fig. Figure 10 is a schematic representation showing a scenario in which the scenario “three-color traffic light ↔ flashing traffic light” and the scenario “detection of push button on / vehicle during flashing signal” are in Fig. 6 will be generated. Fig. Figure 11 is a schematic representation showing time conditions for solutions that apply to the scenario "three-color traffic light ↔ flashing traffic light" in Fig. 6 are set. Fig. Figure 12 is a schematic representation showing time conditions for solutions that apply to the scenario "three-color traffic light ↔ flashing traffic light" in Fig. 6 are set. Fig. Figure 13 is a main sequence showing the driving assistance processing performed by the driving assistance device in this embodiment. Fig. Figure 14 shows a subroutine that demonstrates the processing of solution 1-1, which is performed by the driving assistance operating unit. Fig. Figure 15 shows a subroutine that demonstrates the processing of solution 1-2, which is performed by the driving assistance operating unit. Fig. Figure 16 shows a subroutine that demonstrates the processing of solution 1-3, which is performed by the driving assistance operating unit. Fig. Figure 17 shows a subroutine that demonstrates the processing of solution 1-4, which is performed by the driving assistance operating unit. Fig. Figure 18 shows a subroutine that demonstrates the processing of solutions 1-5, which is performed by the driving assistance operating unit. Fig. Figure 19 shows a subroutine that demonstrates the processing of solutions 3-1 and 3-2, which are performed by the driving assistance operating unit. Fig. Figure 20 is a schematic representation showing an example of a road-vehicle communication configuration in a modification of this embodiment. Fig. Figure 21 is a schematic representation showing a signal cycle information estimation method in the modification of this embodiment. Fig. Figure 22 shows a subroutine that demonstrates the processing of solution 1-1 in the modification of this embodiment. DESIGNS FOR IMPLEMENTING THE INVENTION

[0020] With reference to the drawings, an embodiment of a driving assistance device according to the present invention is described below. In the following drawings, the same or corresponding part is assigned the same reference numeral, and its description is not repeated.

[0021] First, the configuration of a driving assistance device in an embodiment of the present invention is described with reference to Fig. 1 to Fig. 12 described. Fig. Figure 1 is a block diagram showing a general configuration of a driving assistance device in an embodiment of the present invention. Fig. Figure 2 is a schematic representation showing an example of a road-vehicle communication configuration implemented by the driving assistance device in this embodiment. Fig. Figure 3 is a schematic representation showing solution 1-1, which is one of the signal cycle information estimation methods performed by the driving assistance device in this embodiment. Fig. Figure 4 is a schematic representation showing solution 1-4, which is one of the signal cycle information estimation methods performed by the driving assistance device in this embodiment. Fig. Figure 5 is a schematic representation showing solution 3-1, which is one of the signal cycle information estimation methods performed by the driving assistance device in this embodiment. Fig. Figure 6 is a representation that shows an example of the settings for the type of scenario in which signal cycle information is not sent, the scenario determination condition for each scenario, selectable solutions, and deliverable services, all of which are used in the signal cycle information estimation processing. Fig. Figure 7 is a representation that shows an example of the content of situations and means that are in the element "Scenario Determination Condition" in Fig. 6 are listed, Fig. Figure 8 is a representation that shows an example of the settings for the type of scenario in which signal cycle information is not received, the scenario determination condition for each scenario, selectable solutions, and deliverable services, all of which are used in the signal cycle information estimation processing. Fig. Figure 9 is a representation that shows an example of the content of situations and means that are in the element "Scenario Determination Condition" in Fig. 8 are listed, Fig. Figure 10 is a schematic representation showing a scenario in which the scenario “three-color traffic light ↔ flashing traffic light” and the scenario “detection of push button on / vehicle during flashing signal” are in Fig. 6 are generated, Fig. Figure 11 is a schematic representation showing time conditions for solutions that apply to the scenario "three-color traffic light ↔ flashing traffic light" in Fig. 6 are set, and Fig. Figure 12 is a schematic representation showing time conditions for solutions that apply to the scenario "three-color traffic light ↔ flashing traffic light" in Fig. 6 are set.

[0022] In this embodiment, a driving assistance device 1 is applied to a vehicle control system 3 installed in a vehicle 2, which is a host vehicle as described in Fig. Figure 1 shows the driving assistance device 1. This device comprises an HMI device 4 (HMI: "Human Machine Interface"), which functions as an assistance device, and a controller 5, which functions as a control device. The driving assistance device 1, in which the controller 5 controls the HMI device 4 according to the situation to output various types of driving assistance information (HMI information), assists a driver in safely driving the vehicle 2.

[0023] Vehicle 2 has a machine or motor as the energy source for powering the drive wheels. Vehicle 2 can be a hybrid vehicle (HV), which has both a machine and a motor, a conventional vehicle, which has a machine but no motor, or an electric vehicle (EV), which has a motor but no machine.

[0024] In this embodiment, the vehicle control system 3 is a so-called radio wave medium-based infrastructure cooperation system that supports driving by communicating with roadside units installed at the roadside. The vehicle control system 3 acquires various types of information from roadside units, such as signal information, oncoming traffic information, and pedestrian information. The vehicle control system 3 enables the driving assistance device 1 to provide driving assistance information to a driver based on these different types of information. In this way, the driving assistance device 1 provides guidance and support for the driving operation carried out by the driver.

[0025] In this embodiment, the driving assistance device 1 provides the driving assistance service when the vehicle 2 approaches a service target intersection, using the signal cycle information regarding the light color cycles of a traffic signal or traffic light at an intersection where a driving assistance service is provided (hereinafter also referred to as the service target intersection, target intersection, or simply intersection). Specifically, the following services are provided: "traffic signal service" or..."Traffic light service" (also referred to as Service A), which is a safety service to alert a driver regarding a condition in which the driver overlooks no-entry light colors such as a red light or a flashing red light; "Accelerator off assistance or green wave" (also referred to as Service B), which is an eco-service to induce a driver to accelerate or decelerate a vehicle to reduce wasteful fuel consumption or to improve HV (hybrid) regeneration efficiency; and "Eco" is to provide information indicating a time until the end of the red light to enable a driver to start a vehicle quickly.

[0026] Specifically, the vehicle control system 3 is configured to include the HMI device 4, the controller 5, and a status monitoring device 6. The HMI device 4 and the controller 5 configure the driving assistance device 1.

[0027] The HMI device 4 provides driver assistance to support the driving of the vehicle 2. The HMI device 4 can output driver assistance information, which is information to support the driving of the vehicle 2. The HMI device 4 provides driver assistance by supplying driver assistance information to a driver. The HMI device 4 is a vehicle-integrated device. The HMI device 4 is configured to include a display 41 and a loudspeaker (or buzzer) 42, which are provided in the vehicle interior of the vehicle 2. The display 41 is a visual information display device that outputs visual information (graphic information, character information). The loudspeaker 42 is an acoustic (speech) output device that outputs acoustic information (speech information, tone information).HMI device 4 outputs visual and audible information, thereby providing guidance for the driving operations performed by the driver. HMI device 4 provides the information described above to assist the driver in carrying out driving operations.

[0028] The HMI device 4 comprises an accelerator control unit 43, which automatically controls the accelerator pedal opening of the vehicle 2, and a brake control unit 44, which automatically controls the braking force of the vehicle 2. The HMI device 4 directly controls the acceleration and deceleration of the vehicle 2 using the accelerator control unit 43 and the brake control unit 44 to assist the driver in performing driving operations. The HMI device 4, which is electrically connected to the controller 5, is controlled by the controller 5.

[0029] The controller 5 is a control unit that holistically controls the entire vehicle control system 3, including the HMI device 4. The controller 5 is configured as an electronic circuit with a known microcomputer as its main component, the microcomputer comprising a CPU, ROM, RAM, and an interface. The controller 5 is also used as an ECU (electronic control unit) that controls the components of the vehicle 2.

[0030] The condition monitoring device 6, a device for monitoring the condition of the vehicle 2 and the condition around the vehicle 2, monitors the various state values / magnitudes or physical values / magnitudes that characterize the condition of the vehicle 2, as well as the operating state of the switches. The condition monitoring device 6, which is electrically connected to the control unit 5, outputs various signals to the control unit 5. The condition monitoring device 6 is configured to include a road-to-vehicle communication unit 60, a vehicle-to-vehicle communication unit 61, a GPS ECU 62 (GPS: "Global Positioning System"), a map database 63, a car navigation device 64, a vehicle speed sensor 65, a shift position sensor 66, a brake light switch 67, a turn signal switch 68, and so on.

[0031] As it is in Fig. As shown in Figure 2 by way of example, the road-vehicle communication unit 60 is a device that works together with the infrastructure, such as roadside communication units 60a installed at a service target intersection 71, to acquire various types of infrastructure data.

[0032] The service target intersection 71, where driving assistance is provided by the driving assistance device 1, is equipped with the roadside communication units 60a and detection sensors 60b. The detection sensor 60b, such as a radar (millimeter-wave radar), is positioned on a lane located on the road that forms the service target intersection 71 and leads into the intersection 71. Upon detecting that the vehicle 2 is approaching the intersection, the detection sensor 60b transmits data to the roadside communication unit 60a as vehicle detection sensor data. Additionally, upon detecting that a pedestrian is crossing the intersection 71, the detection sensor 60b transmits information to the roadside communication unit 60a as pedestrian information. Although in the schematic representation of Fig. 2 For the sake of description, a detection sensor 60b is illustrated on each road leading into the intersection; a variety of detection sensors 60b are provided according to the number of lanes and the number of pedestrian crossings.

[0033] In addition to the vehicle detection sensor data and pedestrian information detected by the detection sensor 60b described above, the roadside communication unit 60a can also acquire various types of dynamic infrastructure data relating to the environment of the vehicle 2 and the service target intersection 71. The dynamic infrastructure data includes signal cycle information relating to the traffic signals at intersection 71, control signal information for switching the signal types of the traffic signals (including a control start time, a control end time, a signal cycle switching time, a signal type before and after a switchover, pedestrian push-button ON detection information, and vehicle detection information), and road information.

[0034] The roadside communication unit 60a is a communication unit that can wirelessly send and receive data to and from the road-vehicle communication units 60 (so-called road-vehicle communication). In this embodiment, the road-vehicle communication unit 60 and the roadside communication unit 60a acquire various types of information via broadband wireless communication using a radio wave communication medium capable of communication over a wider range than that of narrowband communication using an optical beacon and DSRC (Dedicated Short Range Communication).The road-to-vehicle communication unit 60 and the roadside communication unit 60a can communicate with each other at all times, not only when the vehicle 2 is at an intersection, but also when the vehicle 2 is several hundred meters away from an intersection. This means that various types of information can be transmitted even when the vehicle 2 is approaching an intersection. The road-to-vehicle communication unit 60, which is electrically connected to the controller 5, outputs signals regarding infrastructure data to the controller 5.

[0035] Returning to Fig. 1. The vehicle-to-vehicle communication unit 61 is a device that cooperates with a vehicle-to-vehicle communication unit installed in other vehicles to acquire various types of information concerning those other vehicles. Just like the road-to-vehicle communication unit 60, the vehicle-to-vehicle communication unit 61 transmits and receives various types of information to and from other vehicles via broadband wireless communication using a radio wave communication medium capable of communication over a wider range. The information concerning other vehicles acquired by the vehicle-to-vehicle communication unit 61 includes, at a minimum, information concerning surrounding vehicles or vehicles in the vicinity, information concerning the identification of an emergency vehicle / public vehicle, and / or information concerning surrounding pedestrians.Pedestrians in the vicinity. The vehicle-to-vehicle communication unit 61, which is electrically connected to the control unit 5, outputs signals regarding information from other vehicles to the control unit 5.

[0036] The GPS-ECU 62 is a device that detects the current position of the vehicle 2. The GPS-ECU 62 receives the GPS signal provided by the GPS satellites to specify the position and direction information (GPS information) of the vehicle 2. The GPS-ECU 62, which is electrically connected to the controller 5, outputs the received GPS signal to the controller 5.

[0037] Map database 63 stores static infrastructure information, such as map data that includes road information. For example, the road information includes at least road gradient information, road surface condition information, road shape information, vehicle speed limit information, and / or road curvature (curve) information. The road information stored in map database 63 includes road line shape information regarding the width of a road or the number of lanes, and information about whether a stop line or pedestrian crossing is present. The information stored in map database 63 is referenced by control unit 5 as needed to read necessary information.

[0038] The car navigation device 64 is a device that guides the vehicle 2 to a predetermined destination. From information stored in an internal map information database, information about the current position acquired by the GPS communication unit, and destination information entered by the driver, the car navigation device 64 detects a route to the destination and displays the detected route information on the display unit. The information stored in the car navigation device 64 can include road information similar to that stored in the map database 63. This information is referenced by the controller 5 as needed to read the necessary information.

[0039] The vehicle speed sensor 65 detects the vehicle speed of vehicle 2 (hereinafter referred to as "vehicle speed") as vehicle information. The gear shift position sensor 66 detects the gear position of vehicle 2 selected by the driver as vehicle information. The brake light switch 67 detects whether the driver is pressing the brake pedal on vehicle 2 (braking operation) as vehicle information. The turn signal switch 68 detects whether the driver is activating a turn signal (direction indicator) on vehicle 2 (turn signal operation) as vehicle information.

[0040] The controller 5 described above receives infrastructure data, information from other vehicles, position (GPS) information, and vehicle information, all detected and recorded by the condition monitoring device 6, various types of information stored in the map database 63, and electrical signals corresponding to the driving signals and control commands of the components. The controller 5 controls the components of the vehicle control system 3, including the HMI device 4, in response to the received electrical signals.

[0041] The driving assistance device 1, in which the controller 5 controls the HMI device 4 to perform driving assistance according to the situation, assists a driver by prompting them to carry out a predetermined driving operation. The driving assistance device 1, in which the HMI device 4 outputs various types of driving assistance information under the control of the controller 5 to perform driving assistance, provides a driver with guidance and support to prompt them to carry out a recommended driving operation.

[0042] More precisely, the control unit 5 functionally and conceptually comprises a communication control unit 51, a receiving data processing unit 52, a signal cycle estimation unit 53, a driving support operating unit 54, and an HMI control unit 55, as described in Fig. 1 is shown.

[0043] The communication control unit 51 controls the road-to-vehicle communication unit 60 and the vehicle-to-vehicle communication unit 61. When the vehicle 2 enters an assistance target area and a driving assistance start instruction is given, the communication control unit 51 starts communication via the road-to-vehicle communication unit 60 and the vehicle-to-vehicle communication unit 61.

[0044] The receiving data processing unit 52 performs signal processing on data received via the road-to-vehicle communication unit 60 and the vehicle-to-vehicle communication unit 61. The received data signal has undergone various signal processing operations, such as compression and encryption. The receiving data processing unit 52 restores the data signal after these various processing operations and converts it into a format that the controller 5 can use for various operational processing tasks.

[0045] If infrastructure data received via the road-vehicle communication unit 60 does not, for one reason or another, include signal cycle information regarding the service target intersection 71, the signal cycle estimation unit 53 estimates signal cycle information based on the environmental information regarding intersection 71. The detailed function of the signal cycle estimation unit 53 is described below with reference to Fig. 3 to 12 described.

[0046] The “intersection environment information” used in this embodiment refers specifically to infrastructure data that does not include signal cycle information. For example, as described below, the intersection environment information includes road information relating to intersection 71, whether or not other vehicles or pedestrians are present around intersection 71, the time remaining until the signal type changeover time at intersection 71, captured signal cycle information, and whether or not emergency or public transport vehicles are present around intersection 71. The “infrastructure data” used in this embodiment refers to information that can be captured through cooperation with the infrastructure around the vehicle.The infrastructure data includes information that is not only acquired by the road-vehicle communication unit 60 and the vehicle-to-vehicle communication unit 61, but also by various devices such as the GPS ECU 62, the map database 63 and the car navigation device 64.

[0047] The driver assistance operating unit 54 performs an operation with respect to a driver assistance service. For example, the driver assistance operating unit 54 performs various operations with respect to the driver assistance services A, B, and C described above, based on the infrastructure data surrounding and the signal cycle information with respect to the service destination intersection 71. Additionally, if the signal cycle information with respect to the service destination intersection 71 is not available, the driver assistance operating unit 54 performs an operation with respect to the driver assistance service using the signal cycle information estimated by the signal cycle estimating unit 53.

[0048] The HMI control unit 55 controls the HMI device 4 based on the operating result generated by the driving assistance operating unit 54. The HMI control unit 55 controls the HMI device 4 to cause it to output driving assistance information in order to present driving assistance information to a driver.

[0049] The function of the signal cycle estimation unit 53 in this embodiment is described below with reference to Fig. Sections 3 to 12 are described in detail. If signal cycle information is unavailable, the signal cycle estimation unit 53 estimates the signal cycle information using other information contained in the infrastructure data.

[0050] The Signal Cycle Estimator 53 has a variety of solutions (estimation methods) for estimating signal cycle information. These solutions are divided into eight classes according to the information used in the estimation: 1-1, 1-2, 1-3, 1-4, 1-5, 2, 3-1, and 3-2. The Signal Cycle Estimator 53 estimates signal cycle information using this variety of solutions according to different scenarios or scenes in which the signal cycle information is unavailable. Each of the solutions is described below. (Solution 1-1)

[0051] In solution 1-1, the signal cycle estimator estimates 53 signal cycle information based on the acquired signal cycle information. Referring to Fig. 3. The signal cycle information data is typically retained or stored for several further cycles. In the Fig. In the 3 examples shown, when the signal cycle information is unavailable, the signal cycle information is held or stored for approximately two further cycles.

[0052] In solution 1-1, the captured signal cycle information is used until the held signal cycle ends. Afterward, new signal cycle information is generated because no signal cycle information is held. The signal cycle information is updated by additionally generating signal cycle information using the last cycle X of the captured signal cycle information, while the fluorescent pages are then applied. (Solution 1-2)

[0053] In solution 1-2, the signal cycle estimator 53 estimates signal cycle information based on road information (road line shape information, map information). Specifically, the signal cycle estimator 53 determines the main / secondary or priority / subordinate relationship of the roads leading into the service target intersection 71, using the road line shape information acquired by the road-vehicle communication unit 60 or the map information (or road information) acquired by the vehicle navigation device 64. The signal cycle estimator 53 then determines whether the road on which vehicle 2, namely the host vehicle, is currently traveling is a main / priority road or a secondary road.

[0054] The signal cycle estimation unit then estimates 53 signal cycle pieces of information based on the determined priority / secondary or superior / subordinate relationship of the roadway. Specifically, if the road on which the host vehicle is currently traveling is a priority road, the signal cycle information is updated with the flashing amber light (equivalent to a green light) or the steady green light. If the road is a secondary road, the signal cycle information is updated with the flashing red light (equivalent to a red light) or the steady red light. (Solution 1-3)

[0055] In solution 1-3, the signal cycle estimator 53 estimates signal cycle information based on whether or not other vehicles are present around the intersection. Specifically, the signal cycle estimator 53 receives vehicle detection sensor data collected by the detection sensors 60b at the service target intersection 71 from the road-vehicle communication unit 60, estimates the state of surrounding vehicles both on the road on which the host vehicle is currently traveling and on the road perpendicular to that road, based on the vehicle detection sensor data, and determines the stop request or necessity (permission to proceed) of vehicle 2 at intersection 71.

[0056] The signal cycle estimation unit 53 then estimates the signal cycle information according to the stop requirement or necessity of vehicle 2 at the service target intersection 71. Specifically, if it is determined that vehicle 2 is not required to stop, the signal cycle information is updated to information equivalent to a green light signal. If it is determined that vehicle 2 is required to stop, the signal cycle information is updated to information equivalent to a red light signal. (Solution 1-4)

[0057] In solution 1-4, the signal cycle estimator estimates 53 signal cycle pieces of information based on the signal type switching time. The signal type includes the signal illumination method (methods such as tri-color signal, flashing, push button, vehicle detection) and the signal cycle status (illumination color display sequence, combination of display content).

[0058] Specifically, in Solution 1-4, the signal cycle estimator 53 extracts the signal cycle changeover time (switching time of the signal lighting procedure or signal cycle state) from the infrastructure data and calculates the remaining time until the signal type changeover. The signal cycle estimator 53 then estimates the signal cycle information based on the calculated remaining time, with the duration until the signal cycle changeover time being equivalent to a red light signal. Additionally, if vehicle 2 is stopped at a stop line in intersection 71, the signal cycle estimator 53 can count down the remaining time (number of seconds remaining) until the signal type changeover in order to perform the start notification service (service C). (Solution 1-5)

[0059] In solution 1-5, the signal cycle estimation unit estimates 53 signal cycle information based on whether an emergency vehicle or a public vehicle is around the intersection.

[0060] When the existing FAST (“Fast Emergency Vehicle Preemption System”), PTPS (“Public Transportation Priority System”), or M-MOCS (“Mobile Operation Control System”) is operational, the traffic lights are controlled so that a green light is displayed as a priority at the traffic lights on a road where an emergency vehicle, such as an ambulance or fire engine, or a public vehicle, such as a bus, is traveling. As described in Fig. As shown in Figure 4, at this time the sending of signal cycle information from traffic signal systems or traffic lights that are under the control of FAST / PTPS / M-MOCS during its operating time is stopped.

[0061] With this in mind, the signal cycle estimation unit 53 estimates the signal cycle information in solution 1-5 as follows. It extracts the emergency vehicle flag or the public vehicle flag from other surrounding vehicles using vehicle-to-vehicle communication data. When the vehicle-to-vehicle communication unit 61 detects that an emergency vehicle or public vehicle is approaching, the road on which the emergency vehicle or public vehicle is currently traveling is determined to be a main or priority road at intersection 71, with the intersecting road being determined to be a minor road. If the road on which the host vehicle is currently traveling is a main or priority road, the signal cycle information is updated to information equivalent to a green traffic light; if the road on which the host vehicle is currently traveling is a minor road, the signal cycle information is updated to information equivalent to a green traffic light.If the host vehicle is currently driving on a side street, the signal cycle information is updated to information equivalent to a red light signal. In the... Fig. In example 4, since the road on which vehicle 2 is currently traveling crosses the road on which an emergency vehicle is currently traveling, the road is determined to be a secondary road, with the signal cycle information being updated to information equivalent to a red light signal. (Solution 2)

[0062] In Solution 2, the signal cycle estimator 53 estimates a signal cycle signal assuming that either pedestrians or other vehicles are present around an intersection, in response to the detection that the pedestrian push button is switched ON or that vehicles are present in the intersection. For example, in Solution 2, the signal cycle information for all roads leading into the intersection can be updated to information equivalent to a flashing yellow traffic light.

[0063] Additionally, in Solution 2, information indicating that "pedestrians are waiting to cross the intersection" or "vehicles are waiting to enter the intersection" can be presented to a driver. Providing such information allows for a new service, separate from Services A, B, and C, to alert a driver about pedestrians or vehicles that might enter the intersection without waiting for the signal to change. (Solution 3-1)

[0064] In solution 3-1, the signal cycle estimator estimates 53 signal cycle information according to a processing load on the vehicle's ECU 2.

[0065] As it is in Fig. As shown in Figure 5, the ECU is in a low-load state, where the ECU processing load is lower than a predetermined threshold, or in a high-load state, where the ECU processing load is higher than the predetermined threshold. When the ECU is in a high-load state, the reception of infrastructure data is delayed, and as a consequence, the acquisition of signal cycle information is delayed in some cases. To address this issue, Solution 3-1 does the following: When the ECU processing load becomes high, the acquisition processing of signal cycle information is stopped, as indicated by the hatched area in Figure 5. Fig. Figure 5 shows how to reduce the processing load by prioritizing service provisioning. At that time, as shown in Fig. As shown in Figure 5, the signal cycle information is additionally generated using the acquired signal cycle information, as is the case in Solution 1-1, in order to update the signal cycle information. (Solution 3-2)

[0066] In Solution 3-2, the signal cycle estimation unit estimates 53 signal cycle information based on whether the driver assistance service is provisioned or delivered. Specifically, signal cycle information reception processing is performed as usual before the service is started. From the start until the end of the service (while the service is provisioned or delivered), signal cycle information reception processing is stopped to reduce the processing load, prioritizing service provisioning or delivery. At this time, additional signal cycle information is generated using the acquired signal cycle information, as in Solution 1-1, to update the signal cycle information.

[0067] The signal cycle estimation unit 53 can select one of a variety of solutions for estimating signal cycle information according to different signal cycle information non-acquisition scenarios (situations). These scenarios are broadly divided into two: one in which the signal cycle information sending side (infrastructure) does not transmit the information, and one in which the sending side transmits signal cycle information, but the receiving side (vehicle 2) does not receive it.

[0068] Referring to Fig. 6 and Fig. Section 8 below describes in detail the signal cycle information non-detection scenarios assumed in this embodiment. Fig. Figure 6 is a representation showing an example of the scenario determination condition settings, selectable solution, and deliverable service settings for each of the signal cycle information non-collection scenarios assumed in this embodiment, in which signal cycle information is not sent.

[0069] As it is in Fig. As shown in Figure 6, the following seven types of scenarios are set as a scenario in which signal cycle information is not sent: “tricolor traffic light ↔ flashing traffic light”, “push button ON / vehicle detection during flashing signal”, “tricolor traffic light ↔ push button / vehicle detection traffic light”, “change in signal cycle status”, “increase / decrease in number of lanes and change in lane direction”, “FAST, PTPS, M-MOCS operating time”, and “periodic inspection, unexpected inspection, or manual control by police officer”. (Three-color traffic light ↔ flashing traffic light)

[0070] The scenario "three-color traffic light ↔ flashing traffic light" refers to a scenario in which the signal lighting procedure of a traffic light switches between the three-color procedure and the flashing procedure, as described in Fig. Figure 10 above shows that at this changeover time, and for several minutes before and after the changeover time, the signal cycle information from the roadside transmitter is either not transmitted or is filled with invalid values. The control start time, at which the lighting procedure changes from the tri-color procedure to the flashing procedure, and the control end time, at which the lighting procedure reverts from the flashing procedure to the tri-color procedure, can be determined from the infrastructure data. The driving assistance device can define the several minutes before and after each of the predetermined times as a time zone during which the transmission of signal cycle information is stopped. (Detection of push button ON / vehicle during flashing signal)

[0071] The scenario "Detection of push button ON / vehicle during flashing signal" refers to a scenario in which the flashing traffic light, in response to the detection that the pedestrian push button is switched ON or a vehicle is present, changes its lighting pattern to a three-color illumination, as described in Fig. Figure 10 below shows that at this changeover time, and for several minutes before and after the changeover time within a predetermined time zone, the signal cycle information from the roadside transmitter is either not transmitted or the signal cycle information that is transmitted is filled with invalid values. The driving assistance device can extract information from the infrastructure data about whether it detects that the pedestrian push button is switched ON or whether a vehicle is detected. (Three-color traffic light ↔ Push button / vehicle detection traffic light)

[0072] The scenario "three-color traffic light ↔ push-button / vehicle detection traffic light" refers to a scenario in which the signal lighting method of a traffic light switches between the three-color method and the push-button / vehicle detection method. At this switchover time, and for a predetermined period of several minutes before and after the switchover time, the signal cycle information from the roadside transmitter is either not transmitted or the signal cycle information that is transmitted is filled with invalid values. The control start time, at which the lighting method switches from the three-color method to the push-button / vehicle detection method, and the control end time, at which the lighting method switches back from the push-button / vehicle detection method to the three-color method, can be determined from the infrastructure data.The driving assistance device can define the several minutes before and after the predetermined times as a time zone during which the transmission of signal cycle information is stopped. (Change in signal cycle status)

[0073] The "Change in Signal Cycle Status" scenario refers to a scenario in which the signal cycle status (light color display sequence, combination of display content, etc.) of a traffic light is toggled. At this changeover time, and for a predetermined period of several minutes before and after the changeover time, the signal cycle information is either not transmitted by the roadside transmitter, or the signal cycle information that is transmitted is populated with invalid values. The changeover time of the signal cycle status can be determined from the infrastructure data. The driver assistance device can define the several minutes before and after the predetermined time as a time zone during which the transmission of signal cycle information is stopped. (Increase / decrease in the number of lanes and change in the direction of travel of the lane)

[0074] The scenario "Increase / Decrease in Number of Lanes and Change in Lane Direction" refers to a scenario in which the center line of the roadway or the direction of travel of the lane is changed. At this change time, and for a predetermined period of several minutes before and after the change time, the signal cycle information from the roadside transmitter is either not transmitted or the signal cycle information that is transmitted is filled with invalid values. The roadway shape change time at which these changes occur can be determined from the infrastructure data. (FAST, PTPS, M-MOCS operating time)

[0075] The scenario “FAST, PTPS, M-MOCS operating time” refers to a scenario in which the traffic lights at the intersections ahead in the direction of travel are controlled during the operation of FAST, PTPS or M-MOCS, as described with reference to Fig. 4 is described. The infrastructure data can be used to determine whether FAST, PTPS or M-MOCS is in operation. (Periodic inspection, unexpected inspection or manual control by police officer)

[0076] The scenario "periodic inspection, unexpected inspection, or manual control by police officer" refers to a scenario in which the automatic operation of a traffic light is stopped when a periodic or unexpected inspection is carried out, or when the traffic light is manually controlled by a police officer. The information that the traffic light is undergoing inspection or manual control can be retrieved from the infrastructure data.

[0077] Fig. Figure 8 is a diagram showing an example of the scenario determination condition settings, selectable solution, and deliverable service settings for each of the signal cycle information non-acquisition scenarios assumed in this embodiment, where signal cycle information is not received. As shown in Fig. As shown in Figure 8, the following five scenarios are set as a scenario in which signal cycle information is not received: “Radio wave barrier”, “Radio wave interference”, “Electrical system noise”, “Increased ECU processing load”, and “Partial or device malfunction”.

[0078] The “radio wave barrier” scenario includes a situation of poor visibility that occurs when a large vehicle (truck, bus) is located between vehicle 2 and the infrastructure, or a situation of poor visibility that occurs between vehicle 2 and the roadside infrastructure as a result of the road layout (level separation, curve, gradient, etc.) or the road construction (pedestrian bridge, sign or information panel, etc.).

[0079] The scenario “radio wave interference” includes a situation in which interference is caused by a disturbing radio wave (same frequency), a situation in which the time division multiplexing control of road-vehicle communication or vehicle-vehicle communication is not carried out properly and interference is caused as a result (state of concealed terminal of vehicle-vehicle communication unit), and an effect of the higher harmonic from a high-output wireless unit.

[0080] The “electrical system noise” scenario includes noise generated during the differential operating time of components with insufficient noise protection, such as a windshield wiper and a blower installed on the host vehicle, or such as a compressor or ignition system installed on other vehicles, or noise generated by an environmental factor such as a location near a factory or railway line.

[0081] The scenario "increased ECU processing load" includes situations such as those that occur with reference to Fig. 5 are described in which the receiving processing of infrastructure data is delayed or cannot be carried out, for the following reasons: the processing load of the HMI processing is increased when the driving assistance service is provided based on signal cycle information, or the ECU processing load is increased when other services such as the vehicle-to-vehicle communication service are provided.

[0082] The scenario “partial or device failure” encompasses a situation in which a contact fault, separation, or disturbance or malfunction is generated in the radio antenna, antenna cable, or receiving circuit.

[0083] If signal cycle information is unavailable, the signal cycle estimator 53 determines, based on the acquired infrastructure data, which of the multitude of signal cycle information non-collection scenarios described above corresponds to the current state. Specifically, the signal cycle estimator 53 selects a scenario that satisfies the "scenario determination condition" specified for each of the scenarios in Fig. 6 and Fig. 8 is set as the current scenario. As it is in Fig. 6 and Fig. As shown in Figure 8, the "Scenario Determination Condition" selectively comprises two elements: one is a "Situation" element, which denotes the current data reception state, and the other is a "Means" element, which denotes the information used to determine a scenario. If all elements of a scenario are satisfied, the "Scenario Determination Condition" set for that scenario is determined to be fulfilled.

[0084] For each of the elements of the "scenario determination condition" in Fig. 6. For scenarios where signal cycle information is not sent, a specific content can be set for each of the elements, as described in Fig. Figure 7 shows that for each of the elements of the “scenario determination condition” in Fig. 8. For scenarios where signal cycle information is not received, a specific content can be set for each of the elements, as described in Fig. 9 is shown.

[0085] After determining the current scenario, the signal cycle estimation unit 53 can select a solution from the solutions listed in the "selectable solution" element for each scenario in Fig. 6 and Fig. 8 are set, and the selected solution is executed to estimate the signal cycle information. If a multitude of solutions are set for the scenario, the signal cycle estimation unit 53 selects and uses one solution based on the priority and usability condition set for each solution.

[0086] With reference to Fig. 6, Fig. 11 and Fig. In section 12, the selection of a solution using scenario no. 1 “three-color traffic light ↔ flashing traffic light” is described below as an example.

[0087] Referring to the element "selectable solution" in Fig. Solution 6 is assigned priority 1 to solutions 1-1 and 1-2, priority 2 to solution 1-4, and priority 3 to solution 1-3. Additionally, the following time conditions are assigned: Solution 1-1 is assigned "three-color signal time zone", solution 1-2 is assigned "flashing signal time zone", solution 1-4 is assigned "until the time immediately before switching", and solution 1-3 is assigned "any time zone".

[0088] It was with reference to Fig. 11. Now consider a switching time from a three-color light to a flashing light. Solutions 1-1 and 1-4 are restricted to the time before the control start time. Solution 1-2 is restricted to the time after the control start time. Solution 1-3 can be selected in any time zone before and after the control start time. That is, for a switching time from a three-color light to a flashing light, solutions 1-1, 1-4, and 1-3 are selected in this priority order before the control start time; conversely, solutions 1-2 and 1-3 are selected in this priority order after the control start time.

[0089] Next, with reference to Fig. 12. Consider a switching time from a flashing light to a three-color light. Solutions 1-1, 1-2, and 1-4 are restricted to the time before the control end time. Solution 1-3 can be selected in any time zone before and after the control end time. That is, for a switching time from a flashing light to a three-color light, solutions 1-1, 1-2, 1-4, and 1-3 are selected in this priority order before the control end time, and solution 1-3 is selected after the control end time.

[0090] Once a solution is selected, the signal cycle estimating unit 53 extracts the type of deliverable driver assistance service(s) associated with the solution, as defined in the 'deliverable service' element in Fig. 6 and Fig. 8 is shown, and it sends the extracted service(s) as well as the estimated signal cycle information to the driving assistance operating unit 54. The driving assistance operating unit 54, the HMI control unit 55 and the HMI device 4 use the signal cycle information estimated by the signal cycle estimating unit 53 to provide a deliverable driving assistance service(s) to the driver.

[0091] Next, with reference to Fig. The operation of the driving assistance device 1 in this embodiment is described in sections 13 to 19. Fig. Figure 13 is a main sequence showing the driving assistance processing performed by the driving assistance device in this embodiment. Fig. Figure 14 shows a subroutine that demonstrates the processing of solution 1-1, which is performed by the driving assistance operating unit. Fig. Figure 15 shows a subroutine that demonstrates the processing of solution 1-2, which is performed by the driving assistance operating unit. Fig. Figure 16 shows a subroutine that demonstrates the processing of solutions 1-3, which is performed by the driving assistance operating unit. Fig. Figure 17 shows a subroutine that demonstrates the processing of solutions 1-4, which is performed by the driving assistance operating unit. Fig. Figure 18 shows a subroutine that demonstrates the processing of solutions 1-5, which is performed by the driving assistance operating unit, and Fig. Figure 19 shows a subroutine that demonstrates the processing of solutions 3-1 and 3-2, which are performed by the driving assistance operating unit.

[0092] As it is in the main sequence of Fig. As shown in Figure 13, the communication control unit 51 first confirms whether road-vehicle communication is taking place (S101). The communication control unit 51 can, for example, confirm whether road-vehicle communication is taking place by checking the operating status of the road-vehicle communication unit 60.

[0093] When it is determined that road-to-vehicle communication will take place (Yes in S101), the communication control unit 51 receives infrastructure data about the environment of the vehicle 2 (S102). The communication control unit 51 receives various types of infrastructure data from different devices, such as the road-to-vehicle communication unit 60, the vehicle-to-vehicle communication unit 61, the GPS ECU 62, the map database 63, and the car navigation device 64. The received infrastructure data is sent to the receiving data processing unit 52.

[0094] The receiving data processing unit 52 determines the vehicle position and the vehicle route (S103). The receiving data processing unit 52 calculates the vehicle position, such as the latitude / longitude information of the vehicle 2, based on the information acquired by the GPS ECU 62, and it determines the road on which the vehicle 2 is currently traveling, based on the calculated vehicle position and the road information obtained from the map database 63 or the vehicle navigation device 64. The receiving data processing unit 52 sends the infrastructure data, which includes the determined information regarding the vehicle position and the vehicle route, to the driving assistance operating unit 54.

[0095] If the intersection ahead on the vehicle's route is identified as a target intersection based on the infrastructure data received by the receiving data processing unit 52, the driving assistance operating unit 54 determines the service type (S104) defined for the target intersection.

[0096] At this point, the driver assistance control unit 54 confirms whether signal cycle information can be acquired (S105). Specifically, the driver assistance control unit 54 confirms whether the infrastructure data received by the receiving data processing unit 52 includes signal cycle information. If it is determined that signal cycle information is not available (No in S105), the situation is such that the infrastructure data is being received, but the received infrastructure data does not include signal cycle information. Therefore, processing proceeds to step S107, assuming that a fault or malfunction has occurred on the signal cycle information sending side (at the roadside communication unit).

[0097] If it is determined that signal cycle information can be acquired (Yes in S105), the signal cycle information is updated using the signal cycle information included in the newly acquired infrastructure data (S111). The driving assistance operating unit 54, the HMI control unit 55, and the HMI device 4 provide the driving assistance service using the updated signal cycle information (S112).

[0098] On the other hand, if step S101 determines that road-vehicle communication is not taking place (No in S101), the next step is to confirm whether the road-vehicle service is being performed (S106). If it is determined that the road-vehicle service is being performed (Yes in S106), the situation is such that the road-vehicle service is being performed, but road-vehicle communication is not. Therefore, the processing proceeds to step S107, assuming that the infrastructure data (signal cycle information) cannot be received due to a fault or malfunction in the receive state on the signal cycle information receiver side (at vehicle 2). If it is determined that the road-vehicle service is not being performed (No in S106), the situation is such that neither road-vehicle communication nor the road-vehicle service is being performed.In this case, processing will be terminated without the driver assistance service being performed.

[0099] If step S105 determines that signal cycle information is unavailable (No in S105), or if step S106 determines that the road-vehicle service is being performed (Yes in S106), then signal cycle information is indeed unavailable. Therefore, the signal cycle estimation unit 53 performs the signal cycle estimation processing in step S107 and subsequent steps.

[0100] First, the signal cycle estimator 53 determines a signal cycle information non-acquisition scenario (S107). Using various types of information included in the infrastructure data acquired by the communication control unit 51, the signal cycle estimator 53 checks the situation against a determination condition specified in the "Scenario Determination Condition" element in Fig. 6 and Fig. 8 is listed and set for each scenario, and it determines a scenario that meets all conditions as the signal cycle information non-capture scenario at the current time.

[0101] Next, the signal cycle estimator 53 selects a solution for estimating the signal cycle information according to the signal cycle information non-acquisition scenario determined in step S107 (S108). The signal cycle estimator 53 can select a solution that is associated with the scenario selected in step S107, as described in the "selectable solution" element in Fig. 6 and Fig. Figure 8 is shown as an example. If a large number of solutions are assigned to the scenario, the signal cycle estimation unit 53 selects a solution taking into account the time condition or priority that is individually specified for each solution.

[0102] The subroutine for the solution selected in step S108 is executed to estimate the signal cycle information (S109). The subroutine for each solution is described below with reference to Fig. Described in sections 14 to 19.

[0103] Based on the signal cycle information non-detection scenario determined in step S107 and the solution selected in step S108, with reference to Fig. 6 and Fig. 8. A deliverable service type (S110) was selected that is related to the signal cycle information non-capture scenario and the solution.

[0104] The driving assistance operating unit 54, the HMI control unit 55 and the HMI device 4 use the signal cycle information estimated in step S109 to provide the driving assistance service selected in step S110 (S112).

[0105] Additionally, a check is performed to determine whether the road-vehicle service has ended (S113). If the road-vehicle service continues (No in S113), processing returns to step S101 to repeat the process for continued driving assistance based on signal cycle information. If the road-vehicle service has ended (Yes in S113), processing terminates.

[0106] Next, the subroutines for the solutions that were defined in step S109 of the main flow of Fig. 13 are executed, individually with reference to Fig. Described in sections 14 to 19.

[0107] First, the subroutine of solution 1-1 is referenced to Fig. 14 described.

[0108] A check is performed to determine whether the signal cycle information stored in the driving assistance device 1 is within the effective time (S201). If the stored signal cycle information is within the effective time (Yes in S201), it is written as the latest signal cycle information (S202). Conversely, if the stored signal cycle information is not within the effective time (No in S201), the last signal cycle of the stored signal cycle information is duplicated to generate new signal cycle information (S203).

[0109] Afterwards, the signal cycle information is updated using the signal cycle information generated in step S202 or S203 (S204) and processing returns to the main flow.

[0110] Next, the subroutine of solution 1-2 will be used with reference to Fig. 15 described.

[0111] The road-vehicle communication unit 60 and the car navigation device 64 acquire the road line shape information and the map information (S301). Based on the road line shape information and map information acquired in step S301, the main / minor or priority / subordination relationship at the target intersection is estimated (S302). That is, the subroutine estimates which of each of the roads leading into the target intersection is a main / priority road or a minor road.

[0112] Based on the main / secondary or superior / subordinate relationship at the intersection, which is estimated in step S302, it is determined whether the road on which vehicle 2 is currently traveling is a main / priority road or a secondary road (S303).

[0113] The signal cycle information is updated according to the main / secondary or priority / subordinate relationship of the route, which is determined in step S303 (304), and the processing returns to the main flow. Specifically, the signal cycle information is updated with a flashing yellow light (equivalent to a green light) if the road on which the host vehicle is currently traveling is a main road. If the road on which the host vehicle is currently traveling is a secondary road, the signal cycle information is updated with a flashing red light (equivalent to a red light).

[0114] Next, the subroutine of solution 1-3 will be described with reference to Fig. 16 described.

[0115] The road-vehicle communication unit 60 acquires the vehicle detection sensor data at the target intersection (S401). This means that information about whether vehicles are present on the roads leading into the target intersection is recorded.

[0116] The driving behavior of other vehicles (vehicles ahead or oncoming vehicles) on the road on which vehicle 2 is currently traveling is detected using the vehicle detection sensor data acquired in step S401 (S402). Additionally, the driving behavior of other vehicles on the road that intersects the host vehicle's route at the intersection is detected (S403).

[0117] Based on the driving behavior of the other vehicles on the host road and on the intersecting road, which are detected in step S402 and step S403 respectively, the entry status of the other vehicles into the target intersection is estimated and the stopping request or necessity (the permission to pass) of vehicle 2 at the target intersection is determined (S404).

[0118] The signal cycle signal is then updated according to the stop requirement or necessity determined in step S404 (S405), and processing returns to the main flow. Specifically, the signal cycle information is updated to information equivalent to a green light signal if it is not necessary for the vehicle to stop. Conversely, the signal cycle information is updated to information equivalent to a red light signal if it is necessary for the vehicle to stop.

[0119] Next, the subroutine of solution 1-4 will be described with reference to Fig. 17 described.

[0120] The signal cycle switching time is detected by the road-vehicle communication unit 60 (S501), and a check is performed to determine whether the current time falls within a predetermined range immediately before the switching time (S502). If the current time is determined to be immediately before the switching time (Yes in S502), the remaining time until the switching time is counted (S503) to check whether the remaining time until the switch is equal to or greater than a predetermined value (S504).

[0121] If the remaining time is equal to or greater than the predetermined value (Yes in S504), it is determined that the start notification service (Service C) is available (S505). If the remaining time is less than the predetermined value (No in S504), it is determined that the start notification service (Service C) is not available (S506). Then, using the remaining time calculated in step S503, the signal cycle information is updated, taking into account the remaining time until the status changeover time, i.e., the time from the current time until the signal cycle changeover time, as equivalent to a red light signal (S507). Afterward, processing returns to the main flow.

[0122] If step S502 determines that the current time is not a time immediately before the switchover time (No in S502), it is also possible to determine whether a new information provision service can be provided other than services A, B and C (S508).

[0123] Next, the subroutine of solution 1-5 will be described with reference to Fig. 18 described.

[0124] Data about the surrounding vehicles are collected by the vehicle-to-vehicle communication unit 61 (S601), and based on this vehicle data, the route and proximity situation of an emergency vehicle (such as an ambulance) or a public vehicle (such as a bus) included in the surrounding vehicles are detected (S602).

[0125] The primary / secondary or superior / subordinate relationship of the roads at the target intersection is estimated according to the driving state of the surrounding emergency vehicle or public vehicle detected in step S602 (S603). Specifically, as is determined with reference to Fig. As described in section 4, the route of an emergency vehicle or a public vehicle is a main road or priority road, and the other roads are secondary roads.

[0126] The priority / secondary or dominant / subordinate relationship of the route of vehicle 2 is determined according to the priority / secondary or dominant / subordinate relationship of the target intersection, which is estimated in step S603 (S604). That is, if vehicle 2 is currently traveling on the same road as the emergency vehicle or the public vehicle, the road is determined to be a priority road. If vehicle 2 is currently traveling on other roads, the road is determined to be a secondary road.

[0127] The signal cycle information is then updated according to the main / secondary or priority / subordinate relationship of the route of vehicle 2 determined in step S604 (S605), and processing returns to the main sequence. Specifically, if the route of vehicle 2 is a main or priority road, the signal cycle information is updated to information equivalent to a green traffic signal; if the route is a secondary road, the signal cycle information is updated to information equivalent to a red traffic signal.

[0128] Next, the subroutine processing of solutions 3-1 and 3-2 will be described with reference to Fig. 19 described.

[0129] First, the ECU processing load of vehicle 2 is detected (S701) to check if it is in a high-load state (S702). If the ECU processing load is indeed high (yes in S702), the same processing as for solution 1-1 is performed (S704), and the processing returns to the main flow. That is, if the ECU processing load is high, the infrastructure data reception processing for acquiring new signal cycle information is not performed, and the signal cycle information is updated using the acquired signal cycle information.

[0130] On the other hand, if the ECU processing load is in the low-load state (No in S702), the next step is to check whether a driver assistance service is currently available (S703). If a service is available (Yes in S703), the same processing is performed as for solution 1-1, as in the high-load state (S704).

[0131] If no service is provided (No in S703), the signal cycle information is updated as usual (S705). This means that processing is carried out by the road-vehicle communication unit 60 to receive new infrastructure data and new signal cycle information is extracted from the infrastructure data for use during an update.

[0132] Next, the effect of the driving assistance device in this embodiment will be described.

[0133] In this embodiment, the driving assistance device 1 provides driving assistance to the vehicle 2 based on the signal cycle information regarding the light color cycle of the traffic signal at intersection 71. If the signal cycle information is unavailable, the driving assistance device 1 estimates the signal information based on the infrastructure data, which is the information regarding the environment of intersection 71, and provides driving assistance based on the estimated signal cycle information.

[0134] The driver assistance service, which can be provided by the driver assistance device 1 based on signal cycle information, includes various services such as services A, B, and C, as described above. If signal cycle information is unavailable for any reason, none of these services can be provided. When signal cycle information is unavailable, this embodiment, with the configuration described above, estimates the signal cycle information based on the infrastructure data. Therefore, this embodiment can continuously provide the driver assistance service based on the signal cycle information without interruption, thus enabling a driver assistance service to be performed appropriately even when signal cycle information is unavailable.

[0135] In addition, in this embodiment, the driving assistance device 1 provides a plurality of solutions for estimating signal cycle information and selects one solution to be used for estimating signal cycle information from the plurality of solutions according to a scenario in which signal cycle information is not available.

[0136] This configuration makes it possible to estimate signal cycle information appropriately according to a scenario in which signal cycle information is not available, and to estimate signal cycle information accurately, enabling driver assistance to be provided in an even more appropriate manner even when signal cycle information is not available.

[0137] In addition, in this embodiment, the driving assistance device 1 selects an available service from the driving assistance services according to a selected solution and scenario in which signal cycle information is not available.

[0138] This configuration allows driving assistance to be provided only for a serviceable service according to a scenario in which signal cycle information is not available, thus enabling driving assistance to be provided in a more appropriate manner even when signal cycle information is unavailable.

[0139] The case in which “signal cycle information is not available” for the driving assistance device 1 in this embodiment refers to a case in which the signal cycle information transmitting side is not sending signal cycle information. Even if such a condition occurs and a road infrastructure, such as the roadside communication unit 60a, cannot send signal cycle information, the driving assistance device 1 can continuously provide the driving assistance service based on the signal cycle information without interruption.

[0140] The case in which "signal cycle information is not available" for the driving assistance device 1 in this embodiment refers to a case in which the signal cycle information receiving side does not receive any signal cycle information. Even if such a condition occurs and some communication interference or malfunction occurs between the sending and receiving sides of signal cycle information, the driving assistance device 1 can continuously provide the driving assistance service based on the signal cycle information without interruption.

[0141] The case in which "signal cycle information is not available" for the driving assistance device 1 in this embodiment refers to a situation where the information processing load in the vehicle 2 is high and the reception processing of signal cycle information is delayed. Even if such a condition exists, if signal cycle information is received and processing is consequently delayed, the driving assistance device 1 can continuously provide the driving assistance service based on the signal cycle information without interruption.

[0142] In this embodiment, the driving assistance device 1 additionally determines whether the vehicle 2's route is a main road or a secondary road, based on the road information at intersection 71. As a consequence, the driving assistance device 1 estimates the signal cycle information as equivalent to a green traffic light if the road is a main road; it estimates the signal cycle information as equivalent to a red traffic light if the road is a secondary road. This allows signal cycle information to be estimated based on the road information regarding intersection 71 when the signal cycle information is unavailable, thus enabling the driving assistance service to be provided continuously without interruption based on the signal cycle information.

[0143] In this embodiment, the driving assistance device 1 additionally determines whether it is necessary for the vehicle 2 to stop at intersection 71, based on the presence of other vehicles or pedestrians around intersection 71. As a consequence, the driving assistance device 1 estimates the signal cycle information as equivalent to a green light signal when it is not necessary for the vehicle 2 to stop; it estimates the signal cycle information as equivalent to a red light signal when it is necessary for the vehicle 2 to stop. This allows signal cycle information to be estimated based on the presence of other vehicles or pedestrians around intersection 71 when the signal cycle information is unavailable, thus enabling the driving assistance service to be provided continuously without interruption based on the signal cycle information.

[0144] In addition, in this embodiment, the driving assistance device 1 estimates signal cycle information based on the remaining time until the signal type switching time at intersection 71. This allows signal cycle information to be estimated based on the remaining time until the signal type switching time at intersection 71 when the signal cycle information is unavailable, making it possible to provide the driving assistance service continuously without interruption based on the signal cycle information.

[0145] In addition, in this embodiment, the driving assistance device 1 estimates signal cycle information based on acquired signal cycle information. This allows signal cycle information to be estimated based on acquired signal cycle information when the signal cycle information is unavailable, making it possible to provide the driving assistance service continuously without interruption based on the signal cycle information.

[0146] In addition, in this embodiment, the driving assistance device 1 determines whether the route of the vehicle 2 is a main road or a secondary road, based on the presence of an emergency vehicle or a public vehicle around the intersection 71. As a consequence, the driving assistance device 1 estimates the signal cycle information as equivalent to a green traffic light if the road is a main road; the driving assistance device 1 estimates the signal cycle information as equivalent to a red traffic light if the road is a secondary road.This allows signal cycle information to be estimated based on the presence of an emergency vehicle or a public vehicle around intersection 71 when signal cycle information is unavailable, making it possible to provide the driver assistance service based on signal cycle information continuously without interruption. [Modification]

[0147] Next, a modification of the exemplary embodiment will be presented with reference to Fig. described in sections 20 to 22. Fig. Figure 20 is a schematic representation showing an example of a road-vehicle communication configuration in a modification of this embodiment. Fig. Figure 21 is a schematic representation showing a signal cycle information estimation method in the modification of this embodiment, and Fig. Figure 22 shows a subroutine that demonstrates the processing of solution 1-1 in the modification of this embodiment.

[0148] In this modification, the processing content of solution 1-1, namely one of the multitude of solutions provided by the signal cycle estimation unit 53 of the embodiment described above for estimating signal cycle information, is partially modified.

[0149] Consider a case in which interlocking traffic signal systems are installed before and after the service target intersection 71, and signal cycle information regarding intersection 71 is not transmitted by the roadside communication unit 60a. Interlocking traffic signal systems refer to a multitude of traffic signal systems whose signal cycles interlock or are interwoven. For example, as in Fig. 20 and Fig. As shown in Figure 21, the signal cycles of a multitude of traffic lights arranged in succession along a road are set to the same cycle (or the time required for a cycle between them is set to the same). This multitude of traffic lights is configured to regulate and manage the smooth operation of passing vehicles, for example, to allow a vehicle traveling at a certain speed to pass through a series of traffic lights, each showing a green light. Additionally, the illumination time for a green or red light of the interlocking traffic lights can be flexibly varied according to the number of passing vehicles.

[0150] In solution 1-1 of the embodiment described above, if signal cycle information from the service target intersection 71 is not available, the signal cycle information already acquired is used to estimate new signal cycle information. In contrast, in this modification, the signal cycle information relating to the interlocking or interwoven traffic signal systems before and after the service target intersection 71 (traffic lights a and c in Fig. 20) used to obtain signal cycle information regarding the traffic light system at the service target intersection 71 (traffic light b in Fig. 20) to estimate.

[0151] Specifically, if the signal cycle of an interlocking traffic signal system is changed before or after the service target intersection 71, as described in Fig. Figure 21 confirms the changed luminous color and its increase / decrease time (ΔT). Subsequently, ΔT is also reflected in the same luminous color of the signal cycle information regarding the service target intersection 71. In the Fig. In example 21, the time for the green light of a traffic light a is increased by ΔT, and accordingly, the time for the green light in the second cycle is also increased by ΔT when estimating the signal cycle information regarding the service target intersection 71.

[0152] In this variation, the subroutine of solution 1-1 is configured as described in Fig. 22 is shown by referring to steps S801 and S802 of the subroutine of solution 1-1 of the Fig. The embodiment described in section 14 has been added. Only a portion of the subroutine is described below. Fig. 22 described, which is opposite the one in Fig. The subroutine shown in section 14 has been changed.

[0153] After new signal cycle information is generated in step S203, a check is performed to determine whether the service destination intersection 71 and the intersections before and after service destination intersection 71 are through service destination intersections, each with an interlocking or interwoven signal system, and whether signal cycle information can be captured from the intersections before and after service destination intersection 71 (S801). If the condition in step S801 is not met, processing proceeds to step S204 to update the signal cycle information using the signal cycle information generated in step S203.

[0154] On the other hand, if the condition in step S801 is met, a check is performed to determine whether the basic cycle of signal cycle information at the intersections before and after service target intersection 71 is / has been changed. If the basic cycle is / has been changed, the increase / decrease time ΔT of each light cycle is reflected in the signal cycle information generated in step S203 (S802). The processing then proceeds to step S204 to update the signal cycle information using the signal cycle information generated in step S802.

[0155] While preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments. The components of the embodiments of the present invention can be modified to be easily interchangeable by a person skilled in the art, or to be essentially the same. REFERENCE MARK LIST 1 driving support device 2 vehicles 4 HMI device 5 Control 53 Signal Cycle Estimation Unit 71 Service Destination Intersection

Claims

[1] Driving assistance device for performing driving assistance of a host vehicle based on signal cycle information relating to light color cycles of a traffic signal at an intersection, wherein: If the signal cycle information is not available, the device estimates the signal cycle information based on environmental information regarding the intersection and performs driving assistance based on the estimated signal cycle information. the device includes a variety of estimation methods for estimating the signal cycle information and selects from the variety of estimation methods to be used for estimating the signal cycle information according to a scenario in which the signal cycle information is not available, the device selects a feasible service from driving assistance services according to the selected estimation method and scenario, and The device provides the selected service using signal cycle information estimated by the selected estimation method. [2] Driving assistance device according to claim 1, wherein a case in which the signal cycle information is not available refers to a case in which a sending side of the signal cycle information does not send the signal cycle information. [3] Driving assistance device according to claim 1, wherein a case in which the signal cycle information is not available refers to a case in which a receiving side of the signal cycle information does not receive the signal cycle information. [4] Driving assistance device according to claim 1, wherein a case in which the signal cycle information is not available refers to a case in which an information processing load in the host vehicle is high and a receive processing of the signal cycle information is delayed. [5] Driving assistance device according to any one of claims 1 to 4, wherein the environmental information includes at least road information regarding the intersection, a presence state of other vehicles or pedestrians around the intersection, a remaining time until a signal type switching time at the intersection, detected signal cycle information and / or a presence state of an emergency vehicle or a public vehicle around the intersection. [6] Driving assistance device according to any one of claims 1 to 5, wherein the device determines, based on road information regarding the intersection, whether a route of the host vehicle is a main road or a side road, estimates signal cycle information as equivalent to a green light signal when it is determined that the route is the main road, and estimates signal cycle information as equivalent to a red light signal when it is determined that the route is the side road. [7] Driving assistance device according to any one of claims 1 to 5, wherein the device determines, based on a presence state of other vehicles or pedestrians around the intersection, whether it is necessary for the host vehicle to stop at the intersection, estimates the signal cycle information as equivalent to a green light signal when it is determined that it is not necessary for the vehicle to stop, and estimates the signal cycle information as equivalent to a red light signal when it is determined that it is necessary for the vehicle to stop. [8] Driving assistance device according to any one of claims 1 to 5, wherein the device estimates the signal cycle information based on a remaining time until a signal type switching time at the intersection. [9] Driving assistance device according to any one of claims 1 to 5, wherein the device estimates the signal cycle information based on the detected signal cycle information. [10] Driving assistance device according to any one of claims 1 to 5, wherein the device determines, based on a presence state of an emergency vehicle or a public vehicle around the intersection, whether a route of the host vehicle is a main road or a side road, estimates signal cycle information as equivalent to a green light signal when it is determined that the route is the main road, and estimates signal cycle information as equivalent to a red light signal when it is determined that the route is the side road.

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