FCW device for lean vehicle and FCW method for lean vehicle

Abstract

To perform FCW control different from conventional methods.SOLUTION: Provided is an FCW device for lean vehicle comprising: an alarm part for issuing an alarm to a driver; and one or more control parts for predicting a course of a vehicle and detecting a position of an object around the vehicle, calculating the probability of collision between the vehicle and the object on the basis of the result of the vehicle course prediction and the result of detection of the position of the object around the vehicle, and performing alarm control by the alarm status of the alarm part on the basis of the collision probability. The FCW device for lean vehicle is used by lean vehicles the vehicle bodies of which, when turning, leans towards the inside of the turn. The control part(s), on the basis of images captured by a monocular camera, predicts a position of the object around the vehicle, predicts a course of the vehicle based on a yaw rate of the vehicle obtained from the results detected by a turning state detection part, and performs alarm control using the obtained results.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to a forward collision warning (FCW) device for a lean vehicle and a forward collision warning method for a lean vehicle that issue a FCW to a driver of the lean vehicle. [Background technology]

[0002] Conventionally, there is known an FCW device that issues a warning to a driver of a lean vehicle based on the possibility of a collision with a surrounding object. A lean vehicle turns by tilting the body. An example of a lean vehicle is a motorcycle. For example, Patent Document 1 discloses a device that issues a warning based on the positional relationship between a lean vehicle and a preceding vehicle traveling in front of the lean vehicle when multiple lean vehicles are traveling together. Patent Document 2 discloses a system that captures an image of the front with a camera attached to the lean vehicle, detects surrounding vehicles using the captured image, and issues a warning. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2021 / 060357 [Patent Document 2] Special Publication No. 2021-526681 Summary of the Invention [Problem to be solved by the invention]

[0004] Lean vehicles tend to be lighter and more compact than non-lean vehicles, which do not tilt the vehicle body to the left or right when turning. Therefore, lean vehicles are more likely to sway when subjected to disturbances such as unevenness on the road surface while traveling straight, compared to non-lean vehicles. The techniques disclosed in Patent Documents 1 and 2 do not take into consideration FCW control in a situation where sway occurs due to disturbances such as unevenness on the road surface while the lean vehicle is traveling straight.

[0005] An object of the present disclosure is to provide an FCW device for a lean vehicle and an FCW method for a lean vehicle that perform FCW control different from those proposed in the past. [Means for solving the problem]

[0006] The present inventors have considered activating an FCW device while a lean vehicle is turning. The FCW device detects objects around the host vehicle, and then selects from the detected objects an object that is likely to collide with the host vehicle. A numerical value indicating the degree of risk of the host vehicle colliding with the object varies depending on whether the object is on the path of the host vehicle. The present inventors have come up with the idea that by predicting the path of the host vehicle in consideration of the turning state of the host vehicle, it is possible to execute warning control for objects on the turning path of the host vehicle.

[0007] Furthermore, the inventors of the present application have noticed that in a lean vehicle, the vehicle body is more likely to sway when traveling straight due to disturbances such as unevenness of the road surface compared to a four-wheel vehicle. If the vehicle body sways when traveling straight due to the influence of disturbances, and the swaying is recognized as turning and a course prediction is performed based on this, there is a possibility that a predicted course different from the actual course will be obtained. Therefore, the inventors of the present application have studied an FCW device for a lean vehicle that can execute FCW control that takes into account the swaying state and the turning state that occur due to the influence of disturbances when traveling straight.

[0008] While the situations in which warning control using FCW devices can be performed are expanding, the bodies of lean vehicles are smaller than the bodies of four-wheeled vehicles, limiting the space available for mounting the devices, so there is a demand to reduce the processing load and increase the design freedom of hardware resources.

[0009] In this way, when the FCW device is operated while the lean vehicle is turning, it is necessary to suppress an increase in the processing load while taking into consideration the swaying state and turning state that occur due to external disturbances when the lean vehicle is traveling straight.

[0010] In order to simultaneously address the conflicting issues described above, the FCW device for a lean vehicle according to the present disclosure employs the following configuration.

[0011] An FCW device for a lean vehicle according to one embodiment of the present disclosure includes an alarm unit that issues an alarm to a driver, and one or more control units that execute a host vehicle path prediction that predicts a path of the host vehicle and a host vehicle peripheral object position detection that detects the positions of objects around the host vehicle, calculate a possibility of a collision between the host vehicle and an object using the results of the host vehicle path prediction and the results of the host vehicle peripheral object position detection, and execute an alarm control that controls whether or not an alarm is issued by the alarm unit based on the possibility of collision. The FCW device for a lean vehicle is used in a lean vehicle whose body tilts to the inside of a turn when turning, and further includes a monocular camera that is fixed to the host vehicle and captures an image of the periphery of the host vehicle, and a turning state detection unit that detects a physical quantity related to the yaw rate of the host vehicle, and the control unit executes the position detection of the host vehicle peripheral object based on an image captured by the monocular camera, and executes the host vehicle path prediction that takes into account the yaw rate of the host vehicle obtained from the detection result of the turning state detection unit, and executes the alarm control using the obtained result as described in each of the following situations. Situation 1: When the host vehicle is turning on a road without white lines and a first preceding vehicle is turning in front of the host vehicle at a speed slower than the host vehicle's speed and with the same turning radius as the host vehicle, the control unit executes warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the first preceding vehicle reaches or exceeds a predetermined collision possibility. Situation 2: When the host vehicle is traveling straight on a road without white lines, and a second leading vehicle is traveling straight ahead of the host vehicle at a speed slower than the host vehicle's speed, and the center position of the vehicle width direction of the front wheels of the host vehicle is in a zigzag state, zigzagging within a range that falls within the vehicle width of the host vehicle, centered on a straight line parallel to the direction of travel of the second leading vehicle, and the center position of the vehicle width direction of the front wheels of the host vehicle is located within the vehicle width of the second leading vehicle when viewed from the direction of travel of the second leading vehicle, the control unit executes warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the second leading vehicle reaches a predetermined collision possibility or greater.

[0012] In the above configuration, the control unit may execute the warning control as described in the following situations. Situation 3: When the host vehicle is traveling straight on a road without white lines, a third leading vehicle is traveling straight ahead of the host vehicle at the same speed as the host vehicle, and the host vehicle is in a serpentine state where the center position of the vehicle width of the front wheels of the host vehicle is centered on a straight line parallel to the direction of travel of the third leading vehicle and falls within the vehicle width of the host vehicle, and the center position of the vehicle width of the front wheels of the host vehicle is located within the vehicle width of the third leading vehicle when viewed from the direction of travel of the third leading vehicle, and a fourth leading vehicle is turning at a speed slower than the speed of the host vehicle, following a turning path predicted from the yaw rate generated by the host vehicle traveling straight in the serpentine state, the control unit executes warning control so that an warning is not issued by the warning unit.

[0013] In the above configuration, the FCW device for a lean vehicle may further include a vehicle speed detection unit that detects the vehicle speed of the host vehicle. The control unit may determine whether the host vehicle is turning based on a yaw rate obtained from the detection result of the turning state detection unit, and when it is determined that the host vehicle is turning, may execute the host vehicle course prediction based on the yaw rate obtained from the detection result of the turning state detection unit and the vehicle speed detected by the vehicle speed detection unit, and when the host vehicle is in the meandering state, may execute the host vehicle course prediction by considering the host vehicle to be traveling straight regardless of the value of the yaw rate.

[0014] In the above configuration, when the control unit defines the yaw rate as positive when the vehicle turns to the right relative to the direction of travel and the yaw rate as negative when the vehicle turns to the left relative to the direction of travel, if the duration during which the sign of the yaw rate obtained from the detection result of the turning state detection unit continues to show the same sign is shorter than a predetermined threshold time, the control unit may perform the vehicle trajectory prediction by assuming that the vehicle is traveling straight regardless of the value of the yaw rate.

[0015] The FCW method for a lean vehicle according to one embodiment of the present disclosure includes an alarm unit that issues an alarm to a driver, and one or more control units that execute host vehicle path prediction that predicts a path of the host vehicle and host vehicle peripheral object position detection that detects the positions of objects around the host vehicle, calculate a collision possibility between the host vehicle and an object using the host vehicle path prediction result and the host vehicle peripheral object position detection result, and execute alarm control that controls whether or not an alarm is issued by the alarm unit based on the collision possibility. The FCW method for a lean vehicle according to one embodiment of the present disclosure is executed by an FCW device used in a lean vehicle in which a vehicle body tilts toward the inside of a turn when turning. The FCW method includes the steps of: capturing an image of the surroundings of the host vehicle with a monocular camera fixed to the host vehicle; acquiring an image from the monocular camera and detecting the positions of objects around the host vehicle; acquiring a yaw rate of the host vehicle from a detection result of a turning state detection unit that detects a physical quantity related to the yaw rate of the host vehicle; predicting the host vehicle's course taking into account the yaw rate obtained from the detection result of the turning state detection unit; and executing the warning control as described in each of the following situations using the result of the host vehicle's course prediction and the result of the position detection of objects around the host vehicle. Situation 1: When the host vehicle is turning on a road without white lines and a first preceding vehicle is turning in front of the host vehicle at a speed slower than the host vehicle's speed with the same turning radius as the host vehicle, the control unit executes the warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the first preceding vehicle reaches or exceeds a predetermined collision possibility. Situation 2: When the host vehicle is traveling straight on a road without white lines, and a second leading vehicle is traveling straight in front of the host vehicle at a speed slower than the host vehicle's speed, and the center position of the vehicle width of the front wheels of the host vehicle is in a zigzag state, zigzagging within a range that falls within the vehicle width of the host vehicle, centered on a straight line parallel to the direction of travel of the second leading vehicle, and the center position of the vehicle width of the front wheels of the host vehicle is located within the vehicle width of the second leading vehicle when viewed from the direction of travel of the second leading vehicle, the control unit executes the warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the second leading vehicle reaches a predetermined collision possibility or greater.

[0016] In the above-mentioned configuration, the method may further include the step of executing the warning control as described in the following situations. Situation 3: When the host vehicle is traveling straight on a road without white lines, a third leading vehicle is traveling straight ahead of the host vehicle at the same speed as the host vehicle, and the host vehicle is in a serpentine state where the center position of the vehicle width of the front wheels of the host vehicle is centered on a straight line parallel to the direction of travel of the third leading vehicle and falls within the vehicle width of the host vehicle, and the center position of the vehicle width of the front wheels of the host vehicle is located within the vehicle width of the third leading vehicle when viewed from the direction of travel of the third leading vehicle, and a fourth leading vehicle is turning at a speed slower than the speed of the host vehicle, following a turning path predicted from the yaw rate generated by the host vehicle traveling straight in the serpentine state, the control unit executes the warning control so that the warning unit does not issue a warning.

[0017] In the above configuration, it is determined whether or not the host vehicle is turning based on the yaw rate obtained from the detection result of the turning state detection unit, and if it is determined that the host vehicle is turning, the host vehicle course prediction is performed based on the yaw rate obtained from the detection result of the turning state detection unit and the vehicle speed detected by a vehicle speed detection unit that detects the vehicle speed of the host vehicle, and if the host vehicle is in the serpentine state, the host vehicle course prediction may be performed by assuming that the host vehicle is traveling straight regardless of the value of the yaw rate.

[0018] In the above configuration, if the yaw rate is defined as positive when the vehicle turns to the right relative to the direction of travel, and the yaw rate is defined as negative when the vehicle turns to the left relative to the direction of travel, if the duration during which the sign of the yaw rate obtained from the detection result of the turning state detection unit continues to show the same sign is shorter than a predetermined threshold time, the vehicle path prediction may be performed assuming that the vehicle is traveling straight, regardless of the value of the yaw rate. Effect of the Invention

[0019] According to the lean vehicle FCW device and lean vehicle FCW method of the present disclosure, it is possible to provide a lean vehicle FCW device and lean vehicle FCW method that perform FCW control different from that proposed conventionally. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a diagram for explaining an overview of a lean vehicle FCW device according to a first embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram for explaining an overview of a lean vehicle FCW device according to a second embodiment of the present disclosure. [Diagram 3] FIG. 3 is a diagram for explaining an overview of a lean vehicle FCW device according to a third embodiment of the present disclosure. [Figure 4] FIG. 4 is a diagram for explaining an example of a process for determining whether a lean vehicle has started to turn or has started to wobble while traveling straight. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A lean vehicle FCW device and a lean vehicle FCW method according to an embodiment of the present invention will be described in detail below with reference to the drawings. Prior to the description, terms used in the embodiments will be explained.

[0022] [Lean vehicle] The lean vehicle according to the present disclosure is a vehicle in which the vehicle body tilts to the right when turning right and tilts to the left when turning left. The left and right directions are directions seen from the driver driving the lean vehicle. In this disclosure, the right hand side is described as right, the left hand side as left, the front as front, and the rear as rear, as seen from the driver of the lean vehicle. The "own vehicle" described in this disclosure refers to a lean vehicle. The lean vehicle includes a motorcycle. The own vehicle described in this disclosure refers to a lean vehicle. The inclination of the lean vehicle refers to the body of the lean vehicle being inclined to the left or right with respect to the vertical direction. The inclination of the lean vehicle can be expressed by the inclination angle between the body of the lean vehicle and the vertical direction. When the lean vehicle is traveling straight, the inclination angle is 0 degrees, and when the lean vehicle is turning, the inclination angle is greater than 0 degrees. The lean vehicle includes at least one front wheel and at least one rear wheel. For example, a lean vehicle may have two front wheels and one or two rear wheels, or one front wheel and one or two rear wheels. A lean vehicle may have steered front wheels or steered rear wheels. A lean vehicle runs by driving the drive wheels with a drive source. The drive source may be an internal combustion engine, an electric motor, or a hybrid drive source including an engine and an electric motor.

[0023] [FCW device for lean vehicles] The FCW device for a lean vehicle described in the present disclosure includes an alarm unit, one or more control units, a monocular camera, and a turning state detection unit. The FCW device may further include a vehicle speed detection unit. The FCW device is mounted on a lean vehicle and used.

[0024] [white line] The white lines described in this disclosure refer to lines drawn on the road to indicate the lane in which the vehicle is traveling, and are not intended to be limited in color. For example, the lines may be drawn in other colors, such as yellow. Such lines on the road may be called outer road lines, shoulder strips, diagonal boundary lines, dividing lines, etc. The FCW device can perform FCW control without detecting white lines. In this disclosure, when it is described that the host vehicle is traveling on a road without white lines, this indicates that the FCW control can be performed even on roads without white lines, and is not intended to limit the roads on which the lean vehicle travels to roads without white lines.

[0025] [situation] In this disclosure, situations numbered and described as "Situation 1" show examples of situations in which the operation of the FCW device can be confirmed. One feature of the FCW device is that it executes processes such as detecting the position of objects around the vehicle and predicting the vehicle's path, and can change whether or not to issue an alarm depending on the situation. Each situation numbered and described indicates that the alarm control executed by the FCW device can be confirmed by reproducing this situation, and is not intended to limit the operation of the FCW device to the described situation.

[0026] [Meandering state] The meandering state described in this disclosure includes a state in which the center position of the front wheels of a lean vehicle in the vehicle width direction meanders within the vehicle width of the lean vehicle, centered on a straight line parallel to the traveling direction of the preceding vehicle traveling straight ahead of the lean vehicle. In other words, if a strip-shaped area of ​​the same width as the vehicle width of the lean vehicle is set on the road, the meandering state includes the driving state of the lean vehicle that runs while changing the direction and position of the front wheels within the range that fits within this area. The meandering state is merely an example of a driving state to show one of the characteristics of the FCW control executed when a lean vehicle stumbles, and is not intended to limit the driving state considered to be a meandering state. For convenience of explanation, it is called a meandering state, but it is not intended to limit the driving state to a driving state in which the direction of the front wheels is changed continuously from left to right. The direction or position of the front wheels in a meandering state may be changed only once. For example, a meandering state is when a lean vehicle is moving straight and then changes the direction of the front wheels once to the right or left, then returns to its original position to the right or left of the original straight path and continues moving straight from that position. A meandering state is also when a lean vehicle changes the direction of the front wheels once to the right or left, then changes the direction of the front wheels again to the left or right, then returns to its original straight path and continues moving straight. If a lean vehicle has multiple front wheels, it is sufficient to determine whether or not the vehicle is in a meandering state for any one of the front wheels.

[0027] [Alarm section] The alarm unit described in the present disclosure is an alarm device that issues an alarm to at least the driver of the lean vehicle. The alarm unit issues an alarm targeting at least one of the senses of hearing, vision, and touch. An alarm targeting the sense of hearing may be issued by emitting a voice or an alarm sound from a speaker. An alarm targeting the sense of sight may be issued by displaying information on a display device or illuminating a light-emitting device. An alarm device such as a speaker, a display device, or a light-emitting device may be installed, for example, on a handle or in the vicinity thereof. If the driver wears a helmet, the alarm device may be mounted on the helmet. A device such as a speedometer or a navigation device provided in the lean vehicle may be used as an alarm device. An alarm targeting the sense of touch may be issued by vibrating at least one of a handle, a helmet, and a seat.

[0028] [Control Unit] The control unit described in the present disclosure controls each unit constituting the FCW device. The control unit controls each unit, thereby realizing the functions and operations of the FCW device described in the present disclosure. The control unit is a control device that executes FCW control. The FCW control includes vehicle path prediction, position detection of objects around the vehicle, and warning control. The FCW device may include multiple control units, and multiple processes may be executed in parallel by separate control units. For example, the process related to vehicle path prediction and the process related to position detection of objects around the vehicle may be executed in parallel at the same time. The control unit calculates a numerical value indicating the possibility of collision between the vehicle and the object based on the prediction result of the path of the vehicle and the result of position detection of objects around the vehicle. For example, the time to collision (TTC) may be used as the numerical value indicating the possibility of collision. In addition, the numerical value indicating the possibility of collision may be, for example, the distance between the lean vehicle and the object, the relative moving speed, or the like. The control unit determines whether or not an alarm is necessary and the timing of issuing an alarm based on the possibility of collision, and executes warning control to issue an alarm from the warning device based on the determination result. The control unit can continuously execute warning control while the lean vehicle is traveling, regardless of whether the lean vehicle is traveling straight or turning. A program corresponding to the control unit is prepared in advance in a non-volatile storage device, and the function and operation of the control unit are realized by executing this program by predetermined hardware. The control unit may be realized by an ECU (Electronic Control Unit) for vehicle control, or the FCW device may have a dedicated control unit.

[0029] [Monocular camera] The monocular camera described in this disclosure is an imaging device that captures images of the periphery of a lean vehicle. The FCW device can execute FCW control by using one monocular camera that is smaller than a stereo camera. The monocular camera is fixed to the lean vehicle and used. The monocular camera can capture images of the road ahead on which the lean vehicle travels. The monocular camera captures images of a preceding vehicle traveling ahead of the lean vehicle while the lean vehicle is traveling straight or turning, a vehicle stopped or parked in front of the lean vehicle, and other obstacles. The preceding vehicles captured by the monocular camera include vehicles traveling on a predicted path obtained by vehicle path prediction and vehicles traveling at a position deviating from the predicted path. The monocular camera captures moving images or continuous still images, so that objects around the lean vehicle are continuously captured.

[0030] [Rotation state detection section] The turning state detection unit described in the present disclosure is a detection device that detects a physical quantity related to the yaw rate of a lean vehicle. The yaw rate and yaw angle of the lean vehicle can be identified from the physical quantity detected by the turning state detection unit. For example, the turning state detection unit may detect either the yaw rate or the yaw angle, and calculate the other based on the detection result. For example, an IMU (Inertial Measurement Unit) may be used as the turning state detection unit. Other devices such as a GPS (Global Positioning System) or a gyro sensor may be used as the turning state detection unit.

[0031] [Vehicle speed detection section] The vehicle speed detection unit described in the present disclosure is a detection device that detects the running speed of a lean vehicle. For example, a device that detects the vehicle speed based on the rotation speed of the front or rear wheels and the outer diameter of the tires obtained by using a rotation sensor is used as the vehicle speed detection unit. Other devices, such as a device that detects the vehicle speed from position information by GPS, may be used as the vehicle speed detection unit.

[0032] [Vehicle Path Prediction] The vehicle path prediction described in the present disclosure is a process of predicting the path of the vehicle. The vehicle path prediction also includes predicting the path on the image captured by the monocular camera. Note that the prediction of the path on the captured image may be performed by mapping the path of the vehicle predicted in three-dimensional coordinates in the real world to the corresponding planar coordinates on the captured image. The planar coordinates on the captured image are, for example, an orthogonal coordinate system with the center of the captured image as the origin. When the lean vehicle is traveling straight, the FCW device can predict the path of the lean vehicle on the image captured by the monocular camera based on the mounting position and mounting angle, imaging direction, imaging range, etc. of the monocular camera on the lean vehicle. When the lean vehicle is turning, the FCW device can predict a curved path as the path of the turning lean vehicle based on the detection result by the turning state detection unit. When the lean vehicle is turning, the FCW device can predict the path of the turning lean vehicle by curving and correcting the predicted path on the captured image, which is obtained assuming that the lean vehicle is going straight, based on the detection result by the turning state detection unit. The FCW device can predict the path of the turning lean vehicle in approximately real time after acquiring the captured image by the monocular camera while the lean vehicle is traveling.

[0033] [Detecting the position of objects around the vehicle] The position detection of an object around the vehicle described in the present disclosure is a process of detecting objects around the vehicle and identifying the position of each object. The position detection of an object around the vehicle is performed using an image captured by a monocular camera. Here, the position of an object may be a position on the image captured by the monocular camera. By performing image analysis to detect objects on the image captured by the monocular camera, the objects shown in the captured image and the positions of each object are detected. Such image analysis may be called object detection, object recognition, or the like. Objects detected from the captured image include a preceding vehicle traveling ahead of the lean vehicle while the lean vehicle is traveling straight and while the lean vehicle is turning, a vehicle stopped or parked ahead, and other obstacles. The preceding vehicle detected from the captured image includes a vehicle traveling on a predicted path obtained by the vehicle path prediction and a vehicle traveling at a position deviated from the predicted path. When the detected vehicle is described as a "preceding vehicle," it refers to a vehicle traveling ahead of the lean vehicle in the same direction as the lean vehicle. The FCW device can detect the positions of objects around the vehicle in approximately real time after capturing an image using a monocular camera while the vehicle is traveling.

[0034] [Possibility of collision] The collision probability described in the present disclosure is a numerical value indicating the possibility of a collision between the lean vehicle and a surrounding object. For example, the relative movement speed of the object with respect to the lean vehicle, the distance between the lean vehicle and the object, the time until the lean vehicle collides with the object, etc. can be used as the collision probability. The collision probability is calculated based on the predicted path of the host vehicle obtained by executing the host vehicle path prediction, the position of each object obtained by executing the position detection of the object around the host vehicle, and the relative movement of each detected object and the lean vehicle. For example, the distance from the object detected on the captured image to the lean vehicle is specified by detecting the position of the object around the host vehicle. The direction and movement speed of the detected object relative to the lean vehicle are specified by comparing multiple captured images captured in succession. The time until the collision is specified based on the distance from the object to the lean vehicle and the relative movement speed. Based on the result of comparing the value indicating the collision probability with a threshold value prepared in advance according to the type of collision probability, an alarm control is performed to determine whether or not an alarm is required by the alarm unit and the timing of issuing the alarm. For example, when the time to collision (TTC) is used as the collision probability, a predetermined time is set as a threshold, and alarm control is performed to issue an alarm when the time to collision reaches the threshold time.

[0035] [Hardware configuration] The FCW device according to the present disclosure is characterized in that it executes FCW control that has not been seen in the past. The hardware configuration of the FCW device according to the present disclosure and a lean vehicle equipped with the FCW device can be implemented by a person skilled in the art using the hardware configuration of a device and a lean vehicle known in prior art documents, other publicly known documents, and the prior art. Therefore, a detailed description of the hardware configuration of the FCW device and the lean vehicle will be omitted.

[0036] [others] In this disclosure, a process described as being performed "based on A" or "taking A into consideration" indicates that the process is performed using A, but the information used is not limited to A, and information other than A may also be used. In the present disclosure, when options are described and "at least one" is stated, this means that all possible combinations of multiple options are included. When used in this disclosure, the words "including," "comprising," "having," and their derivatives indicate that other items in addition to the listed items may be included. In the present disclosure, the words "may" and "may" are intended to indicate that these are non-exclusive examples and are not limited to the examples set forth. In the present disclosure, unless the number of components is clearly specified, the number of the components may be one or more. Unless otherwise defined, the terms described in this disclosure have the general meanings as understood by those skilled in the art in the field of FCW control. The FCW device according to the present disclosure is not limited to the configurations described in the following embodiments or the configurations shown in the drawings. The FCW device according to the present disclosure can also be implemented by combining multiple embodiments described below. The FCW device according to the present disclosure can also be implemented in forms other than the embodiments described below, and can also be implemented by modifying the embodiments described below.

[0037] [First embodiment] An FCW device for a lean vehicle according to a first embodiment of the present disclosure will be described with reference to Fig. 1. As shown in Fig. 1, an FCW device 2 for a lean vehicle is provided on a lean vehicle 1 that turns by tilting the vehicle body toward the inside of the turn. The tilt angle θ shown in Fig. 1 indicates the tilt angle of the lean vehicle 1 with respect to the vertical direction. When the lean vehicle 1 is traveling, the tilt angle θ is 0 degrees while traveling straight, and the tilt angle θ is greater than 0 degrees while turning.

[0038] The FCW device 2 includes an alarm unit 21, one or more control units 22, a monocular camera 23, and a turning state detection unit 24.

[0039] The warning unit 21 issues a warning to the driver of the lean vehicle 1. The control unit 22 executes prediction of the path of the lean vehicle 1, i.e., the host vehicle, and detection of the positions of objects around the host vehicle. The control unit 22 calculates the possibility of a collision using the results of the host vehicle path prediction and the results of the position detection of objects around the host vehicle. The control unit 22 executes warning control for controlling whether or not the warning unit 21 issues a warning and the timing of issuing the warning, based on the possibility of a collision.

[0040] As shown within a dashed line frame in FIG. 1, the FCW device 2 executes FCW control including vehicle path prediction, position detection of objects around the vehicle, and warning control.

[0041] A monocular camera 23 fixed to the body of the lean vehicle 1 captures an image of the periphery of the vehicle including the front of the lean vehicle 1. The control unit 22 acquires the captured image captured by the monocular camera 23 (A). The turning state detection unit 24 detects a physical quantity related to the yaw rate of the body of the lean vehicle 1. The control unit 22 acquires the yaw rate based on the physical quantity detected by the turning state detection unit 24 (B).

[0042] The control unit 22 executes position detection of objects around the vehicle based on the captured image (C). The control unit 22 executes vehicle path prediction taking the yaw rate into consideration (D). Using the result obtained by executing the position detection of objects around the vehicle and the result obtained by executing the vehicle path prediction, the control unit 22 executes warning control (E) so that a warning is issued by the warning unit 21 in situations 1 and 2 shown in FIG. 1.

[0043] Situation 1 and situation 2 shown in FIG. 1 show the positional relationship of the leaning vehicle 1 during travel and the leading vehicles 101 and 102 detected by detecting the positions of the objects around the host vehicle, as viewed from above. The dashed-dotted line and the broken line shown in situation 1 and situation 2 are the predicted travel routes of the leaning vehicle 1 obtained by performing the host vehicle travel route prediction. The dashed-dotted line is the travel route of the leaning vehicle 1 obtained by performing the host vehicle travel route prediction. The broken line is the route through which both ends in the vehicle width direction of the leaning vehicle 1 pass when the obtained travel route is traveled by the leaning vehicle 1. If there is an object within the band-shaped area indicated by the two broken lines, there is a possibility of collision with this object while the leaning vehicle 1 continues to travel. For this reason, warning control is executed using the band-shaped area indicated by the broken line as the predicted travel route.

[0044] In situation 1, while the leaning vehicle 1 is turning on a road without a white line, the first leading vehicle 101 is turning at a turning radius equal to that of the leaning vehicle 1 and at a vehicle speed V2 smaller than the vehicle speed V1 of the leaning vehicle 1 (V2 < V1). The first leading vehicle 101 is turning in front of the leaning vehicle 1. The first leading vehicle 101 is turning on the predicted travel route of the leaning vehicle 1.

[0045] In situation 1, when the possibility of collision between the leaning vehicle 1 and the first leading vehicle 101 becomes equal to or greater than a predetermined collision possibility, the control unit 22 executes warning control so that a warning is issued from the warning unit 21. For example, the control unit 22 controls the warning unit 21 to issue a warning when the distance between the leaning vehicle 1 and the first leading vehicle 101 reaches a predetermined distance. For example, the control unit 22 controls the warning unit 21 to issue a warning when the relative speed between the leaning vehicle 1 and the first leading vehicle 101 reaches a predetermined speed. For example, the control unit 22 controls the warning unit 21 to issue a warning when the collision margin time reaches a predetermined time.

[0046] In situation 2, while the lean vehicle 1 is moving straight ahead at the same vehicle speed V1 as in situation 1 on a road without a white line, the second leading vehicle 102 is moving straight ahead in front of the host vehicle at a vehicle speed V2 that is less than the vehicle speed of the host vehicle (V2 < V1). The lean vehicle 1 is in a meandering state where, although it is moving straight ahead, the center position of the front wheels in the vehicle width direction meanders within a range that fits within the vehicle width W of the lean vehicle 1 around a straight line parallel to the traveling direction of the second leading vehicle 102 that is moving straight ahead. Furthermore, the lean vehicle 1 is in a state where it is traveling such that the center position of the front wheels of the host vehicle in the vehicle width direction is located within the vehicle width of the second leading vehicle 102 as viewed from the traveling direction of the second leading vehicle 102.

[0047] In situation 2, when the possibility of collision between the lean vehicle 1 and the second leading vehicle 102 becomes equal to or greater than a predetermined collision possibility, the control unit 22 executes warning control so that a warning is issued by the warning unit 21. The warning control is performed based on any one of the distance between the lean vehicle 1 and the first leading vehicle 101, the relative speed between the lean vehicle 1 and the first leading vehicle 101, and the collision margin time, similar to situation 1.

[0048] When the lean vehicle 1 moves straight ahead while meandering as in situation 2, the value of the yaw rate of the lean vehicle 1 may show a larger value compared to when moving straight ahead. When the host vehicle path prediction is executed based on the yaw rate obtained at this time, for example, as shown in the figure of situation 2, a predicted path 200 that is curved in the same way as when turning in situation 1 is obtained. When the warning control is performed based on this predicted path 200, the second leading vehicle 102 may be regarded as not being on the predicted path, and there is a risk that the second leading vehicle is excluded from the warning target. The control unit 22 avoids this by distinguishing between the turning lean vehicle 1 and the lean vehicle 1 that moves straight ahead while meandering.

[0049] The control unit 22 determines whether the lean vehicle 1 has started to turn or has become in a meandering state while swaying during straight-ahead travel. When it is determined that the lean vehicle 1 has become in a meandering state while swaying during straight-ahead travel, the control unit 22 can execute the warning control without using the predicted path 200 at the time of turning determination. The method for determining the meandering state will be described later.

[0050] In this way, the FCW device 2 predicts the path of the lean vehicle 1 that is turning, and controls the alarm unit 21 to issue an alarm when the possibility of collision with an object on the predicted path becomes a predetermined collision possibility. When the lean vehicle 1 traveling straight starts to meander, the FCW device 2 can determine that the lean vehicle 1 traveling straight is in a meandering state and execute alarm control in the same way as when traveling straight. Situation 1 and situation 2 are examples to illustrate this, and the alarm control by the FCW device 2 is not limited to situation 1 and situation 2. For example, when the first preceding vehicle 101 in situation 1 is stopped on the road, alarm control is executed in the same way as in situation 1 described above. For example, when the second preceding vehicle 102 in situation 2 is stopped on the road, alarm control is executed in the same way as in situation 2 described above. The FCW device 2 can execute alarm control in various other situations as well, based on the path of the lean vehicle 1 predicted by executing the host vehicle path prediction, the position of the object detected by the position detection of the object around the host vehicle, and the relative movement between the lean vehicle 1 and the object.

[0051] [Second embodiment] A lean vehicle FCW device 2 according to a second embodiment of the present disclosure will be described with reference to Fig. 2. Below, contents that overlap with the description of the first embodiment will be omitted, and only contents necessary for describing the FCW device 2 of the second embodiment will be described.

[0052] The FCW device 2 according to the second embodiment has the same configuration as the FCW device 2 according to the first embodiment. The control unit 22 executes host vehicle path prediction and host vehicle peripheral object position detection as described in the first embodiment. The control unit 22 executes warning control so that the warning unit 21 does not issue a warning in situation 3 shown in Fig. 2(a) by using the result obtained by executing the host vehicle peripheral object position detection and the result obtained by executing the host vehicle path prediction.

[0053] In Situation 3, while the lean vehicle 1 is moving straight ahead at a vehicle speed V1 on a road without a white line, a third leading vehicle 103 is moving straight ahead in front of the lean vehicle 1 at the same vehicle speed V1 as the lean vehicle 1. The lean vehicle 1 is in a meandering state where, although it is moving straight ahead, the center position of the front wheels in the vehicle width direction meanders within a range that fits within the vehicle width of the lean vehicle 1 around a straight line parallel to the traveling direction of the third leading vehicle 103 that is moving straight ahead. Furthermore, the lean vehicle 1 is in a state of traveling such that the center position of the front wheels of its own vehicle in the vehicle width direction is located within the vehicle width of the third leading vehicle 103 as viewed from the traveling direction of the third leading vehicle 103.

[0054] In Situation 3, in addition to the third leading vehicle 103, a fourth leading vehicle 104 is traveling at a vehicle speed V2 that is smaller than the vehicle speed V1 of the lean vehicle 1 (V2 < V1). The fourth leading vehicle 104 is turning in front of the predicted path 200. The predicted path 200 indicates the path obtained when the FCW device 2 executes a self-vehicle path prediction that turns at the same yaw rate as the yaw rate obtained from the meandering lean vehicle 1. In reality, when the lean vehicle 1 is in a meandering state, the self-vehicle path prediction based on the yaw rate is not executed.

[0055] When the lean vehicle 1 is in a meandering state, the control unit 22 executes a self-vehicle path prediction assuming that the lean vehicle 1 is moving straight ahead. For this reason, the predicted path of the lean vehicle 1 becomes a band-shaped region extending in the same direction as the traveling direction of the third leading vehicle 103 that is moving straight ahead.

[0056] In Situation 3, the control unit 22 executes warning control so that no warning is issued by the warning unit 21. The fourth leading vehicle 104 traveling at a vehicle speed V2 smaller than the vehicle speed V1 of the lean vehicle 1 moves relatively closer to the lean vehicle 1, but the fourth leading vehicle 104 is at a position outside the predicted path of the lean vehicle 1 that is regarded as moving straight ahead. For this reason, the possibility of collision between the lean vehicle 1 and the fourth leading vehicle 104 becomes equal to or less than a predetermined collision possibility that requires a warning, and the control unit 22 controls the warning unit 21 so as not to issue a warning for the fourth leading vehicle 104.

[0057] The third leading vehicle 103 is on the predicted path of the lean vehicle 1 regarded as going straight, but is traveling at the same vehicle speed V1 as the lean vehicle 1. The distance between the lean vehicle 1 and the third leading vehicle 103 is maintained, and the third leading vehicle 103 is not moving relative to the lean vehicle 1. For this reason, the possibility of collision between the lean vehicle 1 and the third leading vehicle 103 is also below a predetermined collision possibility that requires an alarm, and the control unit 22 controls the alarm unit 21 so as not to issue an alarm for the third leading vehicle 103.

[0058] Figure 2(b) shows a situation where the fifth leading vehicle 105 is going straight at a vehicle speed V2 on the predicted path of the lean vehicle 1 going straight at a vehicle speed V1. When the vehicle speed V2 of the fifth leading vehicle 105 is less than the vehicle speed of the lean vehicle 1 (V2 < V1), the control unit 22 executes alarm control so that an alarm is issued by the alarm unit 21 when the possibility of collision between the lean vehicle 1 and the fifth leading vehicle 105 becomes equal to or greater than a predetermined collision possibility. When the vehicle speed V2 of the fifth leading vehicle 105 is the same as the vehicle speed of the lean vehicle 1 (V2 = V1), since the distance between the lean vehicle 1 and the fifth leading vehicle 105 is maintained, the control unit 22 executes alarm control so that an alarm by the alarm unit 21 is not issued.

[0059] In situation 2 shown in FIG. 1 and situation 3 shown in FIG. 2(a), since the control unit 22 regards the lean vehicle 1 as not being in a turning state, the control unit 22 executes alarm control in the same manner as when the lean vehicle 1 is going straight without meandering, as shown in FIG. 2(b).

[0060] [Third Embodiment] The FCW device 2 for a lean vehicle according to the third embodiment of the present disclosure will be described with reference to FIG. 3. Hereinafter, the content overlapping with the descriptions in the first embodiment and the second embodiment will be omitted, and the content necessary for the description of the FCW device 2 of the third embodiment will be described.

[0061] As shown in FIG. 3(a), the FCW device 2 according to the third embodiment further includes a vehicle speed detection unit 25 that detects the vehicle speed of the lean vehicle 1 in addition to the configuration shown in FIG. 1.

[0062] The control unit 22 determines whether the lean vehicle 1 is moving straight or turning from the yaw rate obtained by using the turning state detection unit 24. The control unit 22 determines whether the lean vehicle 1 is moving straight or turning from the yaw rate obtained by using the turning state detection unit 24. The control unit 22 may determine that the lean vehicle 1 is turning when the magnitude of the yaw rate is equal to or greater than a predetermined threshold. In the case where the yaw rate when the lean vehicle 1 turns to the right with respect to the traveling direction is defined as positive, and the yaw rate when the lean vehicle 1 turns to the left with respect to the traveling direction is defined as negative, the control unit 22 may determine that the lean vehicle 1 is turning when the duration of the sign of the yaw rate is equal to or greater than a predetermined threshold. When it is determined that the lean vehicle 1 is moving straight, the control unit 22 predicts a course ahead in the traveling direction of the lean vehicle 1.

[0063] As shown in FIG. 3(b), when the control unit 22 determines that the lean vehicle 1 is turning, it performs a vehicle trajectory prediction taking into account the turning of the lean vehicle 1 based on the yaw rate obtained using the turning state detection unit 24 and the vehicle speed detected by the vehicle speed detection unit 25 (S1).

[0064] When the lean vehicle 1 turns, a curved predicted path is obtained ahead in the turning direction of the lean vehicle 1, as shown in situation 1 of Fig. 1. When the lean vehicle 1 travels straight, a straight predicted path is obtained ahead in the traveling direction of the lean vehicle 1, as shown in Fig. 2(b).

[0065] When the lean vehicle 1 is in a meandering state, the control unit 22 executes the host vehicle path prediction taking into account the meandering state (S2). Specifically, the control unit 22 executes the host vehicle path prediction when it is determined that the lean vehicle 1 is traveling straight. That is, the control unit 22 executes the host vehicle path prediction regardless of the value of the yaw rate obtained by using the turning state detection unit 24. For example, even if a yaw rate having a value similar to that at the start of turning is obtained, the control unit 22 executes the host vehicle path prediction assuming that the value of the yaw rate is 0 (zero). As a result, when the lean vehicle 1 traveling straight is in a meandering state, the same predicted path as when the lean vehicle 1 is traveling straight is obtained.

[0066] The control unit 22 executes position detection of an object around the host vehicle based on the captured image obtained by the monocular camera 23 (S3). When the lean vehicle 1 is in a meandering state, the control unit 22 executes warning control based on the predicted path obtained by the host vehicle path prediction (S2) taking the meandering state into consideration and the position of the object detected by the position detection of the object around the host vehicle (S3) (S4). On the other hand, when the lean vehicle 1 is not in a meandering state and is not in a straight line state, the control unit 22 executes warning control based on the predicted path obtained by the host vehicle path prediction (S1) taking turns into consideration and the position of the object detected by the position detection of the object around the host vehicle (S3) (S4).

[0067] [How to determine meandering state] An example of a process in which the FCW device 2 for a lean vehicle according to the first to third embodiments determines whether the lean vehicle 1 has started to turn or has started to wobble while traveling straight will be described with reference to FIG.

[0068] Fig. 4(a) is a diagram showing the change over time in the value of the yaw rate obtained from the detection result of the turning state detection unit 24. Fig. 4(a) shows the change in yaw rate when the yaw rate when the lean vehicle 1 turns to the right with respect to the traveling direction is defined as positive, and the yaw rate when the lean vehicle 1 turns to the left with respect to the traveling direction is defined as negative.

[0069] Fig. 4(b) shows the code duration, which is the duration during which the yaw rate shown in Fig. 4(a) continues to show the same code. The threshold value Th shown in Fig. 4(b) is a threshold value for determining whether the lean vehicle 1 is traveling straight or turning. If the code duration is smaller than the threshold value Th, the control unit 22 determines that the lean vehicle 1 is traveling straight.

[0070] 4(c) shows a straight-line flag indicating whether the lean vehicle 1 is traveling straight or not. When the lean vehicle 1 is traveling straight, the value of the straight-line flag is "1." When the lean vehicle 1 is turning, the value of the straight-line flag is "0."

[0071] If the code duration shown in Fig. 4(b) does not exceed the threshold value Th, the control unit 22 determines that the lean vehicle 1 is traveling straight and sets the straight-travel flag to "1" as shown in Fig. 4(c). If the code duration exceeds the threshold value Th, the control unit 22 determines that the lean vehicle 1 is turning and sets the straight-travel flag to "0".

[0072] When the duration of the yaw rate sign is smaller than a predetermined threshold value Th, the control unit 22 determines that the lean vehicle 1 is traveling straight and performs the vehicle path prediction without considering the yaw rate. For example, as described above, the vehicle path prediction is performed with the yaw rate value set to 0 (zero) regardless of the value of the yaw rate detected from the lean vehicle 1.

[0073] In the example shown in FIG. 4, the sign of the yaw rate is positive from time 0 to t1, negative from time t1 to t2, and positive again from time t2 onward. When the lean vehicle 1 is in a meandering state, the sign of the yaw rate changes in this manner within a short period of time. The threshold value Th is set to a value greater than the sign duration when the vehicle is in this meandering state. When the lean vehicle 1 is in a meandering state, the sign duration does not exceed the threshold value, and the lean vehicle 1 is therefore considered to be traveling straight.

[0074] When the lean vehicle 1 starts turning, the code duration becomes longer than when the vehicle is in a snaking state. In the example shown in Fig. 4, the code duration reaches the threshold value Th at time t3. When the code duration exceeds the threshold value Th, i.e., a predetermined time, the lean vehicle 1 is considered to be turning.

[0075] In this way, even if the lean vehicle 1 starts to sway and meander while traveling straight and the yaw rate value indicates a large value that cannot be obtained while traveling straight, the control unit 22 can determine whether the lean vehicle 1 has started to turn or is swaying and meandering while traveling straight, based on whether the time during which the yaw rate continues to show the same sign exceeds the threshold value Th.

[0076] [Variations] In each embodiment, an example in which there is mainly one preceding vehicle has been described, but even when there are multiple preceding vehicles, the FCW device 2 can execute warning control as described above. For example, a priority may be set for each of the multiple preceding vehicles captured by the monocular camera 23, and warning control may be executed based on the priority. Specifically, the FCW device 2 specifies a distance Dx between the predicted course and the preceding vehicle, and a distance Dy between the vehicle and the preceding vehicle on an image captured by the monocular camera 23. For example, when the predicted course shown by the dashed line in Figs. 1 and 2 is displayed on the captured image, the distance to the center line in the vehicle width direction of the preceding vehicle in a direction perpendicular to the predicted course may be set as Dx. If the distance from the start point on the predicted course to the end point set for the preceding vehicle is set as Dx, the distance from this end point to the vehicle may be set as Dy. The FCW device 2 obtains a value P by substituting the distances Dx and Dy specified using the captured image into the calculation formula P=α×Dy+(1−α)×Dx. The value P is a value related to the priority of the object to be warned, and the warning priority is set higher as the value P becomes smaller. α is a weighting coefficient for weighting the distance Dx between the predicted course and the preceding vehicle, or the distance Dy between the own vehicle and the preceding vehicle. For example, the weighting coefficient α may be set appropriately based on the vehicle speeds of the own vehicle and the preceding vehicle. The FCW device 2 calculates the value P of each of the multiple preceding vehicles, and executes warning control based on the obtained priority. For example, warning control may be executed for the preceding vehicle with the smallest value P. Warning control may also be executed for a predetermined number of preceding vehicles in order starting from the preceding vehicle with the smallest value P.

[0077] The configurations illustrated in the above embodiments are merely functional schematics, and are not necessarily physically configured as illustrated. In other words, the form of distribution and integration of each device is not limited to that illustrated, and all or part of the devices can be functionally or physically distributed and integrated in any unit according to various loads, usage conditions, etc. [Industrial Applicability]

[0078] The FCW device for a lean vehicle and the FCW method for a lean vehicle according to the present invention are suitable for performing FCW control different from the conventional one. [Explanation of symbols]

[0079] 1 Lean vehicle 2 FCW device 21 Alarm section 22 Control section 23 Monocular Camera 24 Turning state detection unit 25 Vehicle speed detection unit

Claims

1. an alarm unit that issues an alarm to a driver; one or more control units that execute a host vehicle path prediction for predicting a path of the host vehicle and a host vehicle peripheral object position detection for detecting positions of objects around the host vehicle, calculate a collision possibility between the host vehicle and the object using a result of the host vehicle path prediction and a result of the host vehicle peripheral object position detection, and execute a warning control that controls whether or not the warning unit issues a warning based on the collision possibility; Equipped with A lean vehicle FCW device used in a lean vehicle in which a vehicle body tilts toward the inside of a turn during a turn, a monocular camera fixed to the host vehicle and configured to capture an image of the surroundings of the host vehicle; a turning state detection unit that detects a physical quantity related to a yaw rate of the host vehicle; Further equipped with The control unit is The position of an object around the vehicle is detected based on an image captured by the monocular camera, and the vehicle path prediction is performed taking into account the yaw rate of the vehicle obtained from the detection result of the turning state detection unit, and the warning control is performed using the obtained result as described in each of the following situations. FCW device for a lean vehicle. Situation 1: When the host vehicle is turning on a road without white lines and a first preceding vehicle is turning in front of the host vehicle at a speed slower than the host vehicle's speed and with the same turning radius as the host vehicle, the control unit executes warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the first preceding vehicle reaches or exceeds a predetermined collision possibility. Situation 2: When the host vehicle is traveling straight on a road without white lines, a second leading vehicle is traveling straight in front of the host vehicle at a speed slower than the host vehicle's speed, and the center position of the vehicle width direction of the front wheels of the host vehicle is in a zigzag state, zigzagging within a range that falls within the vehicle width of the host vehicle, centered on a straight line parallel to the direction of travel of the second leading vehicle, and the center position of the vehicle width direction of the front wheels of the host vehicle is located within the vehicle width of the second leading vehicle when viewed from the direction of travel of the second leading vehicle, the control unit executes warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the second leading vehicle reaches a predetermined collision possibility or greater.

2. 2. The FCW device for a lean vehicle according to claim 1, wherein the control unit executes the warning control in the following situations: Situation 3: When the host vehicle is traveling straight on a road without white lines, a third leading vehicle is traveling straight ahead of the host vehicle at the same speed as the host vehicle, the host vehicle is in a serpentine state in which the center position of the vehicle width of the front wheels of the host vehicle is centered on a straight line parallel to the direction of travel of the third leading vehicle and falls within the vehicle width of the host vehicle, the center position of the vehicle width of the front wheels of the host vehicle is located within the vehicle width of the third leading vehicle when viewed from the direction of travel of the third leading vehicle, and a fourth leading vehicle is turning at a speed slower than the speed of the host vehicle, following a turning path predicted from the yaw rate generated by the host vehicle while traveling straight in the serpentine state, the control unit executes warning control so that the warning unit does not issue a warning.

3. A vehicle speed detection unit that detects the vehicle speed Further equipped with The control unit is determining whether or not the host vehicle is turning based on a yaw rate obtained from the detection result of the turning state detection unit, and when it is determined that the host vehicle is turning, executing the host vehicle path prediction based on the yaw rate obtained from the detection result of the turning state detection unit and the vehicle speed detected by the vehicle speed detection unit; When the host vehicle is in the meandering state, the host vehicle is assumed to be traveling straight regardless of the value of the yaw rate, and the host vehicle course prediction is performed.

2. The lean vehicle FCW device according to claim 1 .

4. The control unit is When the yaw rate when the host vehicle turns to the right with respect to the traveling direction is defined as positive, and the yaw rate when the host vehicle turns to the left with respect to the traveling direction is defined as negative, When the duration during which the sign of the yaw rate obtained from the detection result of the turning state detection unit continues to show the same sign is shorter than a predetermined threshold time, the host vehicle is assumed to be traveling straight regardless of the value of the yaw rate, and the host vehicle course prediction is performed.

2. The lean vehicle FCW device according to claim 1 .

5. An FCW method for a lean vehicle, which is executed by an FCW device used in a lean vehicle whose body leans toward the inside of a turn when turning, comprising: a warning unit that issues a warning to a driver; and one or more control units that execute a host vehicle path prediction that predicts a path of the host vehicle and a host vehicle peripheral object position detection that detects the positions of objects around the host vehicle, calculate a collision possibility between the host vehicle and the object using a result of the host vehicle path prediction and a result of the host vehicle peripheral object position detection, and execute warning control that controls whether or not a warning is issued by the warning unit based on the collision possibility, capturing an image of the surroundings of the host vehicle using a monocular camera fixed to the host vehicle; acquiring an image captured by the monocular camera and detecting the positions of objects around the host vehicle; acquiring a yaw rate of the host vehicle from a detection result of a turning state detection unit that detects a physical quantity related to a yaw rate of the host vehicle; A step of predicting a course of the vehicle taking into consideration a yaw rate obtained from a detection result of the turning state detection unit; executing the warning control using the result of the host vehicle trajectory prediction and the result of the position detection of the object around the host vehicle as described in each of the following situations; 2. A lean vehicle FCW method comprising: Situation 1: When the host vehicle is turning on a road without white lines and a first preceding vehicle is turning in front of the host vehicle at a speed slower than the host vehicle's speed and with the same turning radius as the host vehicle, the control unit executes the warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the first preceding vehicle reaches or exceeds a predetermined collision possibility. Situation 2: When the host vehicle is traveling straight on a road without white lines, a second leading vehicle is traveling straight in front of the host vehicle at a speed slower than the host vehicle's speed, and the center position of the vehicle width direction of the front wheels of the host vehicle is in a zigzag state, zigzagging within a range that falls within the vehicle width of the host vehicle, centered on a straight line parallel to the direction of travel of the second leading vehicle, and the center position of the vehicle width direction of the front wheels of the host vehicle is located within the vehicle width of the second leading vehicle when viewed from the direction of travel of the second leading vehicle, the control unit executes the warning control so that the warning unit issues a warning when the possibility of a collision between the host vehicle and the second leading vehicle reaches a predetermined collision possibility or greater.

6. 6. The lean vehicle FCW method of claim 5, further comprising the step of: executing the warning control as described in the following circumstances: Situation 3: When the host vehicle is traveling straight on a road without white lines, a third leading vehicle is traveling straight ahead of the host vehicle at the same speed as the host vehicle, the host vehicle is in a serpentine state in which the center position of the vehicle width of the front wheels of the host vehicle is centered on a straight line parallel to the direction of travel of the third leading vehicle and falls within the vehicle width of the host vehicle, the center position of the vehicle width of the front wheels of the host vehicle is located within the vehicle width of the third leading vehicle when viewed from the direction of travel of the third leading vehicle, and a fourth leading vehicle is turning at a speed slower than the speed of the host vehicle, following a turning path predicted from the yaw rate generated by the host vehicle while traveling straight in the serpentine state, the control unit executes the warning control so that the warning unit does not issue a warning.

7. It is determined whether or not the host vehicle is turning based on a yaw rate obtained from the detection result of the turning state detection unit, and when it is determined that the host vehicle is turning, the host vehicle path prediction is executed based on the yaw rate obtained from the detection result of the turning state detection unit and a vehicle speed detected by a vehicle speed detection unit that detects the vehicle speed of the host vehicle, When the host vehicle is in the meandering state, the host vehicle path prediction is executed assuming that the host vehicle is traveling straight regardless of the value of the yaw rate.

6. The lean vehicle FCW method of claim 5.

8. In the case where a yaw rate when the host vehicle turns to the right with respect to the traveling direction is defined as positive, and a yaw rate when the host vehicle turns to the left with respect to the traveling direction is defined as negative, if the duration during which the sign of the yaw rate obtained from the detection result of the turning state detection unit continues to show the same sign is shorter than a predetermined threshold time, the host vehicle is considered to be traveling straight regardless of the value of the yaw rate, and the host vehicle course prediction is performed.

6. The lean vehicle FCW method of claim 5.

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