Warning device, warning method, and computer program

Abstract

The system suppresses warnings to vehicle occupants regarding the detection of moving objects in areas where warning notifications are undesirable. [Solution] The warning device includes a moving object detection unit 14 that detects moving objects around the vehicle 1, and a warning notification unit 15 that notifies the vehicle occupants of a first warning in response to the detection of a moving object in a first area FA set to the rear side of the vehicle, and a second warning in response to the detection of a moving object in a second area SA set to the front of the first area. The warning notification unit suppresses the second warning when a moving object enters the second area from the first area.

Description

[[Technical Field]]

[0001] The present invention relates to a warning device, a warning method, and a computer program. [[Background Art]]

[0002] Conventionally, there has been known an alert device (e.g., a blind spot monitor (BSM)) that alerts a driver when another vehicle located in a blind spot area of the vehicle driver is detected (e.g., Patent Document 1). [[Prior Art Documents]] [[Patent Documents]]

[0003] [[Patent Document 1]] Japanese Unexamined Patent Application Publication No. 2021-026241 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] However, there are cases where areas where a warning can be issued when a moving object such as another vehicle is detected are restricted by laws and regulations or the like. For example, it is considered undesirable for a warning for a moving object approaching the own vehicle from behind to be continued after the moving object reaches the front end of the own vehicle.

[0005] In view of the above problem, an object of the present invention is to suppress warnings to occupants of a vehicle for detection of a moving object in an area where warning notification is undesirable. [[Means for Solving the Problem]]

[0006] The gist of the present disclosure is as follows.

[0007] (1) A warning device comprising: a moving object detection unit that detects moving objects around a vehicle; and a warning notification unit that notifies the occupants of the vehicle of a first warning in response to the detection of a moving object in a first area set to the rear side of the vehicle, and a second warning in response to the detection of a moving object in a second area set in front of the first area, wherein the warning notification unit suppresses the second warning when the moving object enters the second area from the first area.

[0008] (2) The warning device according to (1) above, wherein the warning notification unit suspends the second warning for a predetermined time when a moving object entering the first area from the rear is detected.

[0009] (3) The warning device according to (2) above, wherein the warning notification unit sets the predetermined time based on the relative speed of the moving body with respect to the vehicle.

[0010] (4) The warning device according to (2) above, wherein the warning notification unit sets the predetermined time based on the length of the moving body in the front-rear direction.

[0011] (5) The warning device according to (2) above, wherein the warning notification unit starts to stop the second warning when the moving body reaches a determination line behind the rear end of the vehicle.

[0012] (6) The warning device according to (1) above, wherein the moving object detection unit detects the moving object located in the first area using a first sensor provided on the vehicle, and detects the moving object located in the second area using a second sensor provided in front of the first sensor on the vehicle.

[0013] (7) The warning device according to (6) above, wherein the warning notification unit stops the second warning when the moving body detected using the second sensor is the same as the moving body detected using the first sensor.

[0014] (8) The warning device according to (7) above, wherein the warning notification unit stops the second warning when the moving body detected using the second sensor in an area behind the second area is the same as the moving body detected using the first sensor.

[0015] (9) The warning device according to any one of (1) to (8) above, wherein the warning notification unit does not suppress the second warning when the moving body enters the first area from the second area.

[0016] (10) The warning device according to any one of (1) to (8) above, wherein the forward boundary of the second area is set at the front end of the vehicle.

[0017] (11) The warning device according to any one of (1) to (8) above, wherein the warning notification unit continues the first warning until the moving object detected in the first area reaches the eye lip reference line in the second area.

[0018] (12) The warning device according to (11), wherein the warning notification unit determines whether the moving body has reached the i-lips reference line based on the relative speed of the moving body with respect to the vehicle.

[0019] (13) A warning method performed by a computer, comprising: detecting a moving object around a vehicle; notifying the occupants of the vehicle of a first warning in response to the detection of the moving object in a first area set to the rear side of the vehicle, and a second warning in response to the detection of the moving object in a second area set in front of the first area; and suppressing the second warning when the moving object enters the second area from the first area.

[0020] (14) A computer program that causes a computer to execute: detecting a moving object around a vehicle; notifying an occupant of the vehicle of a first warning issued in response to detection of the moving object in a first area set on a rear side of the vehicle, and a second warning issued in response to detection of the moving object in a second area set in front of the first area; and suppressing the second warning when the moving object enters the second area from the first area. [Effects of the Invention]

[0021] According to the present disclosure, it is possible to suppress a warning to an occupant of a vehicle against detection of a moving object in an area where a warning notification is undesirable. [Brief Description of the Drawings]

[0022] [Figure 1] Figure 1 is a schematic configuration diagram of a warning system including a warning device according to an embodiment of the present invention. [Figure 2] Figure 2 is a plan view of a vehicle showing an upper portion of the vehicle. [Figure 3] Figure 3 is a functional block diagram of a processor of an ECU. [Figure 4] Figure 4 is a diagram showing an example of a first area and a second area set as warning target regions. [Figure 5] Figure 5 is a diagram showing an example where false detection of a position of a moving object occurs. [Figure 6] Figure 6 is a diagram showing a scene where a moving object overtakes a vehicle. [Figure 7] Figure 7 is a flowchart showing a control routine of warning stop processing in the first embodiment. [Figure 8] Figure 8 is a flowchart showing a control routine of warning notification processing in the first embodiment. [Figure 9] Figure 9 is a diagram showing a scene where a moving object overtakes a vehicle. [Figure 10] Figure 10 is a flowchart showing a control routine of warning stop processing in the second embodiment. [Figure 11]Figure 11 shows a scene in which a moving object overtakes a vehicle. [Figure 12] Figure 12 is a flowchart showing the control routine for the warning stop process in the third embodiment. [Figure 13] Figure 13 is a flowchart showing the control routine for the warning notification process in the third embodiment. [Modes for carrying out the invention]

[0023] Embodiments of the present invention will be described in detail below with reference to the drawings. In the following description, similar components will be given the same reference numerals.

[0024] <First Embodiment> A first embodiment of the present invention will be described below with reference to Figures 1 to 8. Figure 1 is a schematic diagram of a warning system 100 including a warning device according to an embodiment of the present invention. The warning system 100 is mounted on a vehicle 1 (the vehicle itself) and notifies the occupants of the vehicle 1 (e.g., the driver) of a warning as needed. In this embodiment, the vehicle 1 is a four-wheeled automobile.

[0025] As shown in Figure 1, the warning system 100 includes a surrounding information acquisition sensor 2, a vehicle information acquisition sensor 3, a human-machine interface (HMI) 4, and an electronic control unit (ECU) 10. The surrounding information acquisition sensor 2, the vehicle information acquisition sensor 3, and the HMI 4 are electrically connected to the ECU 10 via an in-vehicle network compliant with standards such as CAN (Controller Area Network) or Ethernet.

[0026] The surrounding information acquisition sensor 2 acquires surrounding information of the vehicle 1. The surrounding information acquisition sensor 2 generates surrounding data of the vehicle 1 at predetermined intervals and transmits the surrounding data to the ECU 10. The surrounding information acquisition sensor 2 includes, for example, a distance measuring sensor 21.

[0027] The distance measuring sensor 21 detects the presence of objects around the vehicle 1 by irradiating the vehicle 1 with electromagnetic waves (millimeter waves or laser light) or ultrasonic waves, and measures the distance from the vehicle 1 to the objects. The distance measuring sensor 21 can also measure the speed and direction of objects around the vehicle 1. In other words, the distance measuring sensor 21 generates point cloud data, distance data, speed data, direction data, etc., of objects around the vehicle 1 as surrounding data for the vehicle 1. The distance measuring sensor 21 includes, for example, at least one of millimeter-wave radar, LiDAR (Laser Imaging Detection And Ranging), and sonar (ultrasonic sensor).

[0028] Figure 2 is a plan view of vehicle 1 showing the upper part of vehicle 1. In this embodiment, the warning system 100 includes a rear-side radar 21a and a front-side radar 21b as distance measuring sensors 21. The rear-side radar 21a is provided on vehicle 1 (specifically on the rear-side portion of vehicle 1), and the front-side radar 21b is provided in front of the rear-side radar 21a on vehicle 1 (specifically on the front-side portion of vehicle 1). The rear-side radar 21a is an example of a first sensor, and the front-side radar 21b is an example of a second sensor.

[0029] The rear-side radar 21a emits millimeter waves to the rear-side of the vehicle 1 and generates point cloud data of objects to the rear-side of the vehicle 1. In this embodiment, as shown in Figure 2, the rear-side radar 21a is installed on the left rear-side of the vehicle 1. For example, the rear-side radar 21a is installed on the left corner of the rear bumper of the vehicle 1 and emits millimeter waves to the left rear-side of the vehicle 1. The output of the rear-side radar 21a is transmitted to the ECU 10.

[0030] The front-side radar 21b emits millimeter waves to the front and side of the vehicle 1 and generates point cloud data of objects to the front and side of the vehicle 1. In this embodiment, as shown in Figure 2, the front-side radar 21b is installed on the left front side of the vehicle 1. For example, the front-side radar 21b is installed on the left corner of the front bumper of the vehicle 1 and emits millimeter waves to the left front side of the vehicle 1. The output of the front-side radar 21b is transmitted to the ECU 10.

[0031] The vehicle information acquisition sensor 3 acquires vehicle information (self-vehicle information). At predetermined intervals, the vehicle information acquisition sensor 3 generates vehicle data related to vehicle information (vehicle behavior data, self-position data, etc.) and transmits the vehicle data to the ECU 10. The vehicle information acquisition sensor 3 includes, for example, a vehicle speed sensor 31 and a positioning sensor 32.

[0032] The vehicle speed sensor 31 generates vehicle speed data as behavioral data of vehicle 1. For example, the vehicle speed sensor 31 generates vehicle speed data by detecting the rotational speed of the vehicle's wheels. The output of the vehicle speed sensor 31 is transmitted to the ECU 10.

[0033] The positioning sensor 32 measures the vehicle's own position and generates vehicle position data. For example, the positioning sensor 32 is a GNSS (Global Navigation Satellite System) receiver. A GNSS receiver detects the vehicle's current position (e.g., the latitude and longitude of the vehicle) based on positioning information obtained from multiple (e.g., three or more) positioning satellites. A specific example of a GNSS receiver is a GPS (Global Positioning System) receiver. The output of the positioning sensor 32 is transmitted to the ECU 10.

[0034] The HMI4 is installed inside the vehicle and facilitates the exchange of information between the vehicle 1 and its occupants (e.g., the driver). The HMI4 includes, for example, an input device 41 and an output device 42.

[0035] The input device 41 receives input from the occupants of vehicle 1. The input device 41 includes at least one of a touch panel, operation buttons, operation switches, and a microphone. The HMI 4 transmits the input data entered into the input device 41 by the occupants of vehicle 1 to the ECU 10.

[0036] The output device 42 provides notifications to the occupants of vehicle 1. The output device 42 includes at least one of a display, indicator, warning light, speaker, buzzer, and vibration unit. The HMI 4 notifies the occupants of vehicle 1 of information corresponding to signals transmitted from the ECU 10 via the output device 42.

[0037] The ECU 10 performs various controls on the vehicle 1. As shown in Figure 1, the ECU 10 includes a communication interface 11, a memory 12, and a processor 13. The communication interface 11 and the memory 12 are connected to the processor 13 via signal lines. In this embodiment, one ECU 10 is provided, but multiple ECUs may be provided for each function. Furthermore, the communication interface 11, the memory 12, and the processor 13 may be configured as a single integrated circuit, or they may be configured as separate circuits.

[0038] The communication interface 11 has an interface circuit for connecting the ECU 10 to the in-vehicle network. The ECU 10 is connected to other in-vehicle equipment via the communication interface 11. The communication interface 11 transmits signals received from the surrounding information acquisition sensor 2, the vehicle information acquisition sensor 3, and the input device 41 of the HMI 4 to the processor 13. The communication interface 11 also transmits signals output from the processor 13 to the output device 42 of the HMI 4.

[0039] Memory 12 includes, for example, volatile semiconductor memory (e.g., DRAM (Dynamic Random Access Memory), SRAM (Static Random Access Memory), etc.) and non-volatile semiconductor memory (e.g., ROM (Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), flash memory, etc.). Memory 12 stores temporary data, computer programs used for various processes by the processor 13 (control programs for the ECU 10), ECU 10 setting data, log data, vehicle information, etc.

[0040] The processor 13 has one or more CPUs (Central Processing Units) and their peripheral circuits. The processor 13 executes computer programs stored in the memory 12. The processor 13 may also have other arithmetic circuits such as a logical operation unit, a numerical operation unit, or a graphics processing unit.

[0041] In this embodiment, the ECU 10 functions as a warning device that notifies the occupants of the vehicle 1 of a warning. In particular, in this embodiment, the ECU 10 notifies the occupants of the vehicle of a warning regarding a moving object located to the side of the vehicle 1. Note that the ECU 10 is just one example of a warning device.

[0042] Figure 3 is a functional block diagram of the processor 13 of the ECU 10. As shown in Figure 3, the processor 13 has a moving object detection unit 14 and a warning notification unit 15. The moving object detection unit 14 and the warning notification unit 15 are functional modules that are realized by the execution of a computer program stored in the memory 12 of the ECU 10 by the processor 13 of the ECU 10. These functional modules may also be realized by dedicated arithmetic circuits provided in the processor 13.

[0043] The moving object detection unit 14 detects moving objects around the vehicle 1. In particular, in this embodiment, the moving object detection unit 14 detects moving objects moving to the side of the vehicle 1. In this specification, a moving object is an object that may pass to the side of the vehicle 1 and includes, for example, at least one of a car, motorcycle, bicycle and pedestrian.

[0044] For example, the moving object detection unit 14 detects moving objects around the vehicle 1 based on the output of the surrounding information acquisition sensor 2. Based on the output of the surrounding information acquisition sensor 2, the moving object detection unit 14 acquires identification information of the moving object (e.g., category, name, etc.), location information (e.g., latitude and longitude), speed information (e.g., relative speed to vehicle 1), etc. Alternatively, the moving object detection unit 14 may acquire this information by inputting the output of the surrounding information acquisition sensor 2 into a trained machine learning model (e.g., CNN (Convolutional Neural Network), RNN (Recurrent Neural Network), Transformer, etc.).

[0045] The warning notification unit 15 notifies the occupant of the vehicle 1 (e.g., the driver) of a warning regarding a moving object detected by the moving object detection unit 14. In this embodiment, the warning notification unit 15 notifies the occupant of the vehicle 1 of a warning regarding a moving object located to the side of the vehicle 1. Specifically, a first area and a second area are pre-set as warning target areas, and the warning notification unit 15 notifies the occupant of the vehicle 1 of a warning when a moving object is detected in a warning target area.

[0046] Figure 4 shows an example of a first area FA and a second area SA that are set as warning areas. The first area FA and the second area SA are areas on the side of vehicle 1 that are difficult for the driver of vehicle 1 to see directly. The first area FA is set on the rear side of vehicle 1, and the second area SA is set in front of the first area FA (on the front side of vehicle 1). In this embodiment, the first area FA and the second area SA are areas on the left side of vehicle 1. That is, the first area FA is set on the left rear side of vehicle 1, and the second area SA is set on the left front side of vehicle 1.

[0047] In this embodiment, the moving object detection unit 14 detects moving objects located in the first area FA using the rear-side radar 21a and detects moving objects located in the second area SA using the front-side radar 21b. In other words, the first area FA is the area where moving objects are detected by the rear-side radar 21a, and the second area SA is the area where moving objects are detected by the front-side radar 21b. Note that the first area FA is a narrower area than the detectable range of the rear-side radar 21a, and the second area SA is a narrower area than the detectable range of the front-side radar 21b.

[0048] The front boundary of the first area FA is set between the dividing line SL, which divides the vehicle 1 in the longitudinal direction, and the rear end of the vehicle 1. The rear boundary of the first area FA is set behind the rear end of the vehicle 1. The front boundary of the second area SA is set at the front end of the vehicle 1. The rear boundary of the second area SA is set in front of the front boundary of the first area FA, and in this embodiment, it is set between the dividing line SL and the front end of the vehicle 1. By setting the first area FA and the second area SA in this way, it is possible to effectively alert the driver to moving objects in the blind spots of the vehicle 1.

[0049] Furthermore, the position of the rear boundary of the second area SA may be between the front boundary of the first area FA and the dividing line SL. Also, although there is a space between the first area FA and the second area SA in the example of Figure 4, the first area FA and the second area SA may be continuous regions in the longitudinal direction of the vehicle 1. In addition, the position of the rear boundary of the first area FA may be changed according to the relative speed of the moving object with respect to the vehicle 1. For example, the faster the relative speed of the moving object approaching the vehicle 1, the longer the distance from the rear boundary of the first area FA to the rear end of the vehicle 1 will be.

[0050] The warning notification unit 15 notifies the occupants of vehicle 1 of a first warning in response to the detection of a moving object in the first area FA, and a second warning in response to the detection of a moving object in the second area SA. This allows the occupants of vehicle 1 (especially the driver) to pay attention to moving objects located in the blind spots of vehicle 1, thereby assisting in the driving of vehicle 1 (for example, changing lanes of vehicle 1).

[0051] Incidentally, in a scenario where a moving object approaches vehicle 1 from behind and overtakes vehicle 1, after the moving object reaches the front of vehicle 1, it moves away from the front of vehicle 1, making it unlikely that the moving object will obstruct vehicle 1's lane change. Therefore, to avoid unnecessary warnings to the occupants of vehicle 1, it is desirable to suppress the warning for the moving object after it reaches the front of vehicle 1. In fact, the Chinese standard (standard number: GB / T39265-2020, name: Road vehicles - Performance requirements and test methods for blind spot detection (BSD) systems) prohibits warnings for such moving objects.

[0052] However, errors may occur in the detection position of moving objects in the longitudinal direction of vehicle 1. In particular, when a moving object is located directly beside an on-board radar such as the rear-side radar 21a and the front-side radar 21b, reflected waves from the side become dominant, reducing detection accuracy.

[0053] Figure 5 shows an example of a false detection of the position of a moving object. In Figure 5, the moving object is shown as a surrounding vehicle 200. In Figure 5, the actual position of the surrounding vehicle 200 is shown by a solid line, and the detected position of the surrounding vehicle 200 is shown by a dashed line. In this example, because the reflection from the reflection point RP directly beside the front-side radar 21b is strong, it is determined that the surrounding vehicle 200 has not reached the front end of vehicle 1, even though a portion of the surrounding vehicle 200 is located in front of the front end of vehicle 1. In such a situation, if a second warning is issued to the occupants of vehicle 1 in response to the detection of the surrounding vehicle 200 by the front-side radar 21b, a warning will be issued for the detection of a moving object in an area where a warning notification is undesirable, and there is a risk of violating regulations such as the Chinese standard mentioned above.

[0054] Therefore, in this embodiment, the warning notification unit 15 suppresses the second warning when the moving object overtakes the vehicle 1, that is, when the moving object enters the second area SA from the first area FA. This prevents warnings to the moving object from being notified even after the moving object has reached the front end of the vehicle 1 due to false detection of the moving object's position. Consequently, it is possible to suppress warnings to the occupants of the vehicle 1 in response to the detection of a moving object in an area where warning notification is undesirable.

[0055] For example, when the warning notification unit 15 detects a moving object entering the first area FA from the rear, it suspends the second warning for a predetermined time. As a result, when the moving object overtakes the vehicle 1, the warning corresponding to the detection of the moving object by the front-side radar 21b in the second area SA is suspended, thus avoiding warnings for moving objects that have reached the front of the vehicle 1.

[0056] When the moving object has completely left the second area SA, there is no moving object directly to the side of the front-side radar 21b, so the possibility of false detection and determination that the moving object is located in the second area SA is low. For this reason, the predetermined time for suspending the second warning (hereinafter referred to as the "warning suspension time") is set to the estimated time required for the moving object that entered the first area FA to completely leave the second area SA, that is, the estimated time required for the rear end of the moving object detected in the first area FA to reach the forward boundary of the second area SA.

[0057] In this case, the warning notification unit 15 sets the warning stop time based, for example, on the relative speed of the moving object with respect to the vehicle 1. This improves the accuracy of the estimated required time and, consequently, allows the warning stop time to be set to an appropriate value. The estimated required time decreases as the relative speed of the moving object increases. Therefore, the warning notification unit 15 shortens the warning stop time as the relative speed of the moving object increases.

[0058] Furthermore, in this embodiment, the warning notification unit 15 sets the warning stop time based on the length of the moving body in the longitudinal direction. By considering the length of the moving body in the longitudinal direction, the accuracy of the estimated required time can be further improved. The longer the length of the moving body in the longitudinal direction, the longer the time from when the front end of the moving body reaches the front boundary of the second area SA to when the rear end of the moving body reaches the front boundary of the second area SA. In other words, the estimated required time increases as the length of the moving body in the longitudinal direction increases. For this reason, the warning notification unit 15 increases the warning stop time as the length of the moving body in the longitudinal direction increases.

[0059] In this embodiment, the warning notification unit 15 starts to stop the second warning when the moving object reaches a determination line behind the rear end of the vehicle 1. This makes it possible to stop the second warning before the moving object is detected in the second area SA, thereby reliably avoiding unnecessary warnings caused by false detection by the front side radar 21b.

[0060] Figure 6 shows a scene in which a moving object overtakes vehicle 1. In Figure 6, a motorcycle 300 is shown as the moving object passing to the side of vehicle 1. The determination line JL is set within the first area FA and is located between the rear end of vehicle 1 and the rear boundary of the first area FA. The position of the determination line JL is set, for example, based on the characteristics of the rear-side radar 21a so that the moving object can be accurately detected at the position of the determination line JL.

[0061] In this embodiment, the warning stop time Ts is calculated by the following equation (1) based on the relative velocity Vr of the moving object with respect to the vehicle 1. The relative velocity Vr is calculated based on the output of the rear-side radar 21a during the period until the moving object reaches the determination line JL. Ts = Ds / Vr…(1) Here, Ds is the distance a moving object that has reached the judgment line JL in the first area FA travels until it completely leaves the second area SA.

[0062] The distance Ds is calculated by the following formula (2). Ds = dj + dv + dm + dr ... (2) Here, dj is the distance from the determination line JL to the rear end of vehicle 1, dv is the longitudinal length of vehicle 1, and dm is the longitudinal length of the moving object (motorcycle 300 in the example of Figure 6). dr is the radar error set based on the rear-side radar 21a characteristics and is predetermined so that the second warning is not activated before the moving object completely leaves the second area SA. Note that the radar error dr may be zero, in which case the endpoint of distance Ds corresponds to the front end of the moving object when it has completely left the second area SA.

[0063] The longitudinal length dm of the moving object is obtained based on the output of the rear-side radar 21a. If the category of the moving object is obtained instead of the length, the warning notification unit 15 sets the longitudinal length dm of the moving object to a length corresponding to the category of the moving object. In this case, for example, the category of the moving object includes automobiles, two-wheeled vehicles (bicycles or motorcycles), and people. The length corresponding to the category is predetermined, and is increased in the order of people, two-wheeled vehicles, and automobiles. Furthermore, if it is difficult to obtain both the length and category of the moving object, the warning notification unit 15 sets the longitudinal length dm of the moving object to a length corresponding to automobiles, which is longer than two-wheeled vehicles and people. This makes it possible to avoid insufficient warning stop time Ts regardless of the category of the moving object.

[0064] On the other hand, when vehicle 1 overtakes the moving object, in a situation like that shown in Figure 5, even if part of the moving object is actually located in front of the second area SA, the moving object will then move to the misdetected position and obstruct vehicle 1's lane change. For this reason, even if the second warning is issued in a situation like that shown in Figure 5, it is unlikely that this warning will be considered unnecessary. In fact, there are currently no laws prohibiting such warnings.

[0065] Therefore, in this embodiment, the warning notification unit 15 does not suppress the second warning when vehicle 1 overtakes a moving object, that is, when the moving object enters the first area FA from the second area SA. This allows the attention of the occupants of vehicle 1 to be directed towards the moving object being overtaken by vehicle 1 when the object is located in the second area, thereby appropriately supporting the driving of vehicle 1.

[0066] The following describes the processing flow for executing the control described above, with reference to Figures 7 and 8. Figure 7 is a flowchart of the control routine for the warning stop process in the first embodiment. This control routine is repeatedly executed by the processor 13 of the ECU 10, for example, according to a computer program stored in the memory 12 of the ECU 10.

[0067] First, in step S101, the warning notification unit 15 of the processor 13 determines whether the warning stop flag F is zero. The warning stop flag F is set to 1 when the second warning is stopped and to zero when the second warning is not stopped (when the second warning is activated). The value of the warning stop flag F is stored in the memory 12 of the ECU 10, and the initial value of the warning stop flag F when the power switch (e.g., ignition switch) of the vehicle 1 is turned on is set to zero.

[0068] If the warning stop flag F is determined to be zero in step S101, the control routine proceeds to step S102. In step S102, the warning notification unit 15 determines, based on the output of the surrounding information acquisition sensor 2 (specifically, the rear-side radar 21a), whether a moving object approaching the vehicle 1 from the rear-side has reached the determination line JL. If it is determined that the moving object has not reached the determination line JL, the control routine terminates. On the other hand, if it is determined that the moving object has reached the determination line JL, the control routine proceeds to step S103.

[0069] In step S103, the warning notification unit 15 calculates the warning stop time Ts using the above formula (1). Next, in step S104, the warning notification unit 15 sets the warning stop flag F to 1. That is, the warning notification unit 15 stops the second warning. After step S104, this control routine terminates.

[0070] On the other hand, if it is determined in step S101 that the warning stop flag F is 1, the control routine proceeds to step S105. In step S105, the warning notification unit 15 determines whether the elapsed time since the warning stop flag F was set to 1, that is, the elapsed time since the second warning was stopped, is equal to or greater than the warning stop time Ts. If it is determined that the elapsed time is less than the warning stop time Ts, the control routine terminates. On the other hand, if it is determined that the elapsed time is equal to or greater than the warning stop time Ts, the control routine proceeds to step S106.

[0071] In step S106, the warning notification unit 15 sets the warning stop flag F to zero. That is, the warning notification unit 15 releases the stop for the second warning. After step S106, this control routine terminates.

[0072] The warning stop time Ts may be a predetermined fixed time. Furthermore, the warning notification unit 15 may stop supplying power to the front-side radar 21b when stopping the second warning. This prevents power from being consumed to acquire unnecessary output from the front-side radar 21b.

[0073] Figure 8 is a flowchart showing the control routine for the warning notification process in the first embodiment. This control routine is repeatedly executed by the processor 13 of the ECU 10, for example, according to a computer program stored in the memory 12 of the ECU 10.

[0074] First, in step S201, the warning notification unit 15 of the processor 13 determines whether or not a moving object has been detected in the first area FA by the moving object detection unit 14. In other words, the warning notification unit 15 determines whether or not a moving object located in the first area FA has been detected by the moving object detection unit 14. The moving object detection unit 14 detects a moving object in the first area FA based on the output of the surrounding information acquisition sensor 2 (specifically, the rear-side radar 21a).

[0075] If it is determined in step S201 that a moving object has been detected in the first area FA, the control routine proceeds to step S202. In step S202, the warning notification unit 15 notifies the occupants of vehicle 1 of a first warning. For example, the warning notification unit 15 uses the output device 42 of the HMI 4 to notify the occupants of vehicle 1 of at least one of a visual warning and an auditory warning as the first warning. As a specific example, an indicator built into the left side mirror of vehicle 1 is provided as the output device 42, and the warning notification unit 15 notifies the first warning by lighting up this indicator. After step S202, the control routine terminates.

[0076] On the other hand, if it is determined in step S201 that no moving object has been detected in the first area FA, the control routine proceeds to step S203. In step S203, the warning notification unit 15 determines whether the warning stop flag F is 1 or not. If it is determined that the warning stop flag F is 1, the control routine terminates without determining whether or not there is a moving object in the second area SA.

[0077] On the other hand, if the warning stop flag F is determined to be zero in step S203, the control routine proceeds to step S204. In step S204, the warning notification unit 15 determines whether or not a moving object has been detected in the second area SA by the moving object detection unit 14. In other words, the warning notification unit 15 determines whether or not a moving object located in the second area SA has been detected by the moving object detection unit 14. The moving object detection unit 14 detects a moving object in the second area based on the output of the surrounding information acquisition sensor 2 (specifically, the front-side radar 21b).

[0078] If it is determined in step S204 that no moving object has been detected in the second area SA, this control routine terminates. On the other hand, if it is determined in step S204 that a moving object has been detected in the second area SA, this control routine proceeds to step S205. In step S205, the warning notification unit 15 notifies the occupants of vehicle 1 of a second warning. For example, the warning notification unit 15 uses the output device 42 of the HMI4 to notify the occupants of vehicle 1 of at least one of a visual warning and an auditory warning as a second warning. Specifically, an indicator built into the left side mirror of vehicle 1 is provided as the output device 42, and the warning notification unit 15 notifies of the second warning by lighting up this indicator. After step S205, this control routine terminates.

[0079] In this embodiment, the warning methods for the first and second warnings are the same, but the warning methods for the first and second warnings may be different. For example, the first warning may include both a visual and an auditory warning, while the second warning may be a visual warning.

[0080] <Second Embodiment> The configuration and control of the warning device according to the second embodiment are basically the same as those of the warning device according to the first embodiment, except for the points described below. Therefore, the second embodiment of the present invention will be described below, focusing on the differences from the first embodiment.

[0081] Figure 9 shows a scene in which a moving object overtakes vehicle 1. In Figure 9, a motorcycle 300 is shown as a moving object passing to the side of vehicle 1. As described above, the warning notification unit 15 suppresses the second warning when a moving object enters the second area SA from the first area FA. Normally, when a moving object enters the second area SA from the first area FA, the moving object (motorcycle 300, solid line in Figure 9) is first detected by the rear-side radar 21a, and then the same moving object (motorcycle 300, dashed line in Figure 9) is detected by the front-side radar 21b.

[0082] Therefore, in the second embodiment, the warning notification unit 15 stops the second warning when the moving object detected using the front-side radar 21b is the same as the moving object detected using the rear-side radar 21a. As a result, when the same moving object is detected by both the rear-side radar 21a and the front-side radar 21b, the warning corresponding to the detection of the moving object by the front-side radar 21b is stopped, thus avoiding warnings for moving objects that have reached the front end of the vehicle 1.

[0083] Because the detectable range of the front-side radar 21b is wider than that of the second area SA, as shown in Figure 9, the front-side radar 21b detects moving objects in the area behind the second area SA (specifically, the area between the first area FA and the second area SA). In other words, the warning notification unit 15 stops the second warning when the moving object detected using the front-side radar 21b in the area behind the second area SA is the same as the moving object detected using the rear-side radar 21a. This ensures that false detection of the position of a moving object in the second area SA is avoided.

[0084] For example, the warning notification unit 15 determines that a moving object detected using the front-side radar 21b is the same as a moving object detected using the rear-side radar 21a when the first condition is met. The first condition is that predetermined parameters acquired by the front-side radar 21b are similar to predetermined parameters acquired by the rear-side radar 21a (for example, the difference between the parameters is less than or equal to a predetermined value). The predetermined parameters include at least one of the velocity of the recognized object (moving object), reflected power, number of reflection points, shape of the recognized object, and direction of movement of the recognized object.

[0085] Furthermore, the warning notification unit 15 may determine, when the second condition is met, that the moving object detected using the front-side radar 21b is the same as the moving object detected using the rear-side radar 21a. The second condition is that the position of the recognized object detected by the front-side radar 21b is similar to the future position of the recognized object (e.g., position after a predetermined time) estimated based on the output of the rear-side radar 21a (e.g., the velocity and direction of travel of the recognized object).

[0086] Furthermore, the warning notification unit 15 may determine that the moving object detected using the front-side radar 21b is the same as the moving object detected using the rear-side radar 21a when both the first and second conditions are met. That is, in the second embodiment, the warning notification unit 15 determines that the moving object detected using the front-side radar 21b is the same as the moving object detected using the rear-side radar 21a when at least one of the first and second conditions is met.

[0087] Figure 10 is a flowchart of the control routine for the warning stop process in the second embodiment. This control routine is repeatedly executed by the processor 13 of the ECU 10 according to a computer program stored in the memory 12 of the ECU 10, for example.

[0088] First, in step S301, similar to step S101 in Figure 7, the warning notification unit 15 of the processor 13 determines whether the warning stop flag F is zero. If it is determined that the warning stop flag F is zero, the control routine proceeds to step S302.

[0089] In step S302, the warning notification unit 15 determines whether a moving object has been detected by the moving object detection unit 14 using the front-side radar 21b. If it is determined that no moving object has been detected, this control routine terminates. On the other hand, if it is determined that a moving object has been detected, this control routine proceeds to step S303.

[0090] In step S303, the warning notification unit 15 determines whether the moving object detected using the front-side radar 21b is the same as the moving object detected (most recently) using the rear-side radar 21a. For example, the warning notification unit 15 determines that the moving object detected using the front-side radar 21b is the same as the moving object detected using the rear-side radar 21a when at least one of the first and second conditions described above is met. If it is determined that the moving objects are not the same, this control routine terminates. On the other hand, if it is determined that the moving objects are the same, this control routine proceeds to step S304.

[0091] In step S304, the warning notification unit 15 sets the warning stop flag F to 1. That is, the warning notification unit 15 stops the second warning. After step S304, this control routine terminates.

[0092] On the other hand, if the warning stop flag F is determined to be 1 in step S301, the control routine proceeds to step S305. In step S305, the warning notification unit 15 determines whether the detection of the same moving object by the front-side radar 21b has finished. That is, the warning notification unit 15 determines whether the moving object determined to be the same has moved out of the detectable range of the front-side radar 21b. If it is determined that the detection of the same moving object has not finished, the control routine terminates. On the other hand, if it is determined that the detection of the same moving object has finished, the control routine proceeds to step S306.

[0093] In step S306, the warning notification unit 15 sets the warning stop flag F to zero. That is, the warning notification unit 15 releases the stop for the second warning. After step S306, this control routine terminates.

[0094] In step S303, unlike the example in Figure 9, it may be determined whether the moving object detected using the front-side radar 21b when at least a part of the moving object enters the second area SA is the same as the moving object detected using the rear-side radar 21a. Also, in step S305, the warning notification unit 15 may determine whether the elapsed time since the warning stop flag F was set to 1, that is, the elapsed time since the second warning was stopped, is equal to or greater than a predetermined time.

[0095] In the second embodiment, as in the first embodiment, the control routine for the warning notification process shown in Figure 8 is executed.

[0096] <Third Embodiment> The configuration and control of the warning device according to the third embodiment are basically the same as those of the warning device according to the first embodiment, except for the points described below. Therefore, the third embodiment of the present invention will be described below focusing on the differences from the first embodiment.

[0097] Figure 11 shows a scene in which a moving object overtakes vehicle 1. In Figure 11, a motorcycle 300 is shown as a moving object passing to the side of vehicle 1. As described above, the warning notification unit 15 suppresses the second warning when the moving object enters the second area SA from the first area FA. However, it is desirable that warnings for moving objects located in the blind spot of vehicle 1 continue even after the moving object has left the first area FA.

[0098] Therefore, in the third embodiment, the warning notification unit 15 continues the first warning until the moving object detected in the first area FA reaches the eye lip reference line EEL in the second area SA. This suppresses unnecessary warnings due to false detection of the position of the moving object in the second area SA, while directing the attention of the vehicle 1's occupants (especially the driver) to the moving object located in the vehicle 1's blind spot.

[0099] The eye lips, as defined in ISO 4513, are ellipses representing the eye ranges (a statistical representation of the distribution of the driver's eye positions) of the driver's right and left eyes in side and top views. In this specification, the eye lips reference line EEL is a reference line in the vehicle width direction (left-right direction) shown on the eye lips. The eye lips reference line EEL can be set for each vehicle type, for example, according to the Japanese Industrial Standard (JIS D 00211: Driver's Eye Range for Automobiles).

[0100] In this embodiment, as shown in Figure 11, the eye lip reference line EEL is set between the dividing line SL, which divides the vehicle 1 in the longitudinal direction, and the front end of the vehicle 1. The eye lip reference line EEL is also set within the second area SA, and is set between the front boundary and the rear boundary of the second area SA.

[0101] The warning notification unit 15 continues the first warning from, for example, when the moving body reaches the determination line JL behind the rear end of the vehicle 1 until the warning duration has elapsed. In this embodiment, the warning duration Tc is calculated based on the relative speed of the moving body with respect to the vehicle 1, and the warning notification unit 15 determines whether or not the moving body has reached the i-lips reference line EEL based on the relative speed of the moving body. This makes it possible to set the warning duration Tc to an appropriate value and to suppress the continuation of the first warning even after the moving body has reached the front end of the vehicle 1.

[0102] The warning duration Tc is calculated by the following formula (3). The relative velocity Vr is calculated based on the output of the rear-side radar 21a during the period until the moving object reaches the judgment line JL. Tc = Dc / Vr…(3) Here, Dc is the distance from the judgment line JL to the i-lips reference line EEL.

[0103] The distance Dc is calculated by the following formula (4). Ds = dj + de…(4) Here, dj is the distance from the judgment line JL to the rear end of vehicle 1, and de is the distance from the rear end of vehicle 1 to the iris reference line EEL.

[0104] The following describes the process flow for executing the control in the third embodiment with reference to Figures 12 and 13. Figure 12 is a flowchart of the control routine for the warning stop process in the third embodiment. This control routine is repeatedly executed by the processor 13 of the ECU 10, for example, according to a computer program stored in the memory 12 of the ECU 10.

[0105] First, in step S401, similar to step S101 in Figure 7, the warning notification unit 15 of the processor 13 determines whether the warning stop flag F is zero. If it is determined that the warning stop flag F is zero, the control routine proceeds to step S402.

[0106] If the warning stop flag F is determined to be zero in step S401, the control routine proceeds to step S402. In step S402, similar to step S102 in Figure 7, the warning notification unit 15 determines whether the moving object approaching the vehicle 1 from the rear side has reached the determination line JL. If it is determined that the moving object has not reached the determination line JL, the control routine terminates. On the other hand, if it is determined that the moving object has reached the determination line JL, the control routine proceeds to step S403.

[0107] In step S403, similar to step S103 in Figure 7, the warning notification unit 15 calculates the warning stop time Ts. Next, in step S404, the warning notification unit 15 calculates the warning duration Tc using the above formula (3).

[0108] Next, in step S405, the warning notification unit 15 sets the warning stop flag F to 1. That is, the warning notification unit 15 stops the second warning. After step S405, this control routine terminates.

[0109] On the other hand, if the warning stop flag F is determined to be 1 in step S401, the control routine proceeds to step S406. Steps S406 and S407 are executed in the same manner as steps S105 and S106 in Figure 7, and after step S407, the control routine terminates.

[0110] Figure 13 is a flowchart of the control routine for the warning notification process in the third embodiment. This control routine is repeatedly executed by the processor 13 of the ECU 10, for example, according to a computer program stored in the memory 12 of the ECU 10.

[0111] Steps S501 to S505 are executed in the same way as steps S201 to S205 in Figure 8. On the other hand, if the warning stop flag F is determined to be 1 in step S503, this control routine proceeds to step S506.

[0112] In step S506, the warning notification unit 15 determines whether the elapsed time since the warning stop flag F was set to 1, that is, the elapsed time since the moving object reached the determination line JL, is less than or equal to the warning duration Tc. If it is determined that the elapsed time is longer than the warning duration Tc, this control routine terminates. On the other hand, if it is determined that the elapsed time is less than or equal to the warning duration Tc, this control routine proceeds to step S502.

[0113] In step S502, similar to step S202 in Figure 8, the warning notification unit 15 notifies the occupants of vehicle 1 of the first warning. After step S502, this control routine terminates.

[0114] <Other Embodiments> Although preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and various modifications and changes can be made within the scope of the claims. For example, the warning notification unit 15 may suppress the second warning when a moving object enters the first area FA from the second area SA. Also, the forward boundary of the first area FA may be set at another position, such as the iris reference line EEL.

[0115] Furthermore, the distance measuring sensor 21 may be provided on the right side of the vehicle 1 instead of the left side of the vehicle 1, or on the right side of the vehicle 1 in addition to the left side of the vehicle 1. In this case, the first area FA and the second area SA are set as the area on the right side of the vehicle 1, and a warning is issued to moving objects passing on the right side of the vehicle 1, similar to the embodiments described above. Also, in the first or third embodiment, instead of the rear side radar 21a and the front side radar 21b, a single side radar that includes the first area FA and the second area SA in its detectable range may be provided on the side of the vehicle 1 (at least one of the left side and the right side) as the distance measuring sensor 21.

[0116] Furthermore, a server or the like, located outside the vehicle 1 and capable of communicating with the vehicle 1, may function as a warning device. In this case, information for detecting objects around the vehicle 1, such as the output of the surrounding information acquisition sensor 2, is transmitted from the vehicle 1 to the server, and the vehicle 1's ECU 10 notifies the occupants of the vehicle 1 of a warning via the output device 42 based on instructions from the server. In addition, the vehicle 1 may be an autonomous driving vehicle in which at least a portion of the vehicle 1's acceleration, braking, and steering are performed automatically.

[0117] Furthermore, the second and third embodiments can be implemented in combination. In this case, in the second embodiment, the warning notification unit 15 continues the first warning until the moving object detected in the first area FA reaches the iris reference line EEL in the second area SA.

[0118] Furthermore, a computer program that enables a computer to implement the functions of each part of the processor 13 of the ECU 10 or the server's processor may be provided in the form of a recording medium readable by a computer, or as part of a computer program product. The recording medium readable by a computer may be, for example, a magnetic recording medium, an optical recording medium, or a semiconductor memory. [Explanation of symbols]

[0119] 1 vehicle 10. Electronic Control Unit (ECU) 13 processors 14. Moving object detection unit 15 Warning notification section 200 surrounding vehicles 300 Motorcycle FA Area 1 SA Area 2

Claims

1. A moving object detection unit that detects moving objects around the vehicle, A warning notification unit that notifies the occupant of the vehicle of a first warning in response to the detection of the moving object in a first area set to the rear side of the vehicle, and a second warning in response to the detection of the moving object in a second area set in front of the first area. Equipped with, The warning notification unit is a warning device that suppresses the second warning when the moving body enters the second area from the first area.

2. The warning device according to claim 1, wherein the warning notification unit suspends the second warning for a predetermined time when a moving object entering the first area from the rear is detected.

3. The warning device according to claim 2, wherein the warning notification unit sets the predetermined time based on the relative speed of the moving body with respect to the vehicle.

4. The warning device according to claim 2, wherein the warning notification unit sets the predetermined time based on the length of the moving body in the front-rear direction.

5. The warning device according to claim 2, wherein the warning notification unit starts to stop the second warning when the moving body reaches a determination line behind the rear end of the vehicle.

6. The warning device according to claim 1, wherein the moving object detection unit detects the moving object located in the first area using a first sensor provided on the vehicle, and detects the moving object located in the second area using a second sensor provided in front of the first sensor on the vehicle.

7. The warning device according to claim 6, wherein the warning notification unit stops the second warning when the moving object detected using the second sensor is the same as the moving object detected using the first sensor.

8. The warning device according to claim 7, wherein the warning notification unit stops the second warning when the moving object detected using the second sensor in an area behind the second area is the same as the moving object detected using the first sensor.

9. The warning device according to any one of claims 1 to 8, wherein the warning notification unit does not suppress the second warning when the moving body enters the first area from the second area.

10. The warning device according to any one of claims 1 to 8, wherein the forward boundary of the second area is set at the front end of the vehicle.

11. The warning device according to any one of claims 1 to 8, wherein the warning notification unit continues the first warning until the moving object detected in the first area reaches the eye lip reference line in the second area.

12. The warning notification unit determines whether the moving body has reached the eye lip reference line based on the relative speed of the moving body with respect to the vehicle, according to claim 11.

13. A warning method performed by a computer, Detecting moving objects around the vehicle, To notify the occupants of the vehicle of a first warning in response to the detection of the moving object in a first area set to the rear side of the vehicle, and a second warning in response to the detection of the moving object in a second area set in front of the first area, The second warning is suppressed when the moving body enters the second area from the first area. Warning methods, including those mentioned above.

14. Detecting moving objects around the vehicle, To notify the occupants of the vehicle of a first warning in response to the detection of the moving object in a first area set to the rear side of the vehicle, and a second warning in response to the detection of the moving object in a second area set in front of the first area, The second warning is suppressed when the moving body enters the second area from the first area. A computer program that causes a computer to execute something.

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