FCW device for saddle-riding type vehicle and FCW method for saddle-riding type vehicle

Abstract

To perform FCW control different from conventional methods.SOLUTION: Provided is an FCW device for saddle-riding type 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 saddle-riding type vehicle is used by saddle-riding type vehicles. The control part(s) calculates time change of the detected relative position of the object to the vehicle, resulting from detecting a position of the object around the vehicle based on images captured by a monocular camera, and performs alarm control, using the predicted vehicle course, the detected position of the object around the vehicle and the result of the time change of the relative position.SELECTED DRAWING: Figure 1

Description

[Technical field]

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

[0002] Conventionally, there is known an FCW device that issues a warning to a driver of a saddle-type vehicle based on the possibility of a collision with a surrounding object. An example of a saddle-type vehicle is a motorcycle. For example, Patent Document 1 discloses a device that issues a warning based on the positional relationship between a saddle-type vehicle and a preceding vehicle traveling in front of the vehicle when multiple saddle-type vehicles are traveling together. Patent Document 2 discloses a system that captures an image of the front with a camera attached to the saddle-type 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] A saddle-type vehicle has a greater degree of freedom in terms of the relative position that it can take with respect to surrounding vehicles while traveling, compared to a non-saddle-type four-wheel vehicle. The techniques disclosed in Patent Documents 1 and 2 do not fully consider FCW control that takes into account the above-mentioned characteristics of a saddle-type vehicle.

[0005] An object of the present disclosure is to provide an FCW device for a saddle-ride type vehicle and an FCW method for a saddle-ride type vehicle that perform FCW control different from conventional ones. [Means for solving the problem]

[0006] In the FCW device for a saddle-type vehicle, it is considered to calculate the collision probability between the surrounding vehicles and the vehicle itself by using the positions of objects (surrounding vehicles) around the vehicle itself on an image captured by an on-board camera and the predicted course information of the vehicle itself. The inventors of the present application have considered using the conventional technologies of Patent Documents 1 and 2 in the FCW device for a saddle-type vehicle in various situations. As a result of the consideration, the inventors of the present application have noticed that there are situations where the surrounding vehicles are on the predicted course of the vehicle itself even though the possibility of a collision is low. Examples of such scenes include a scene where an oncoming vehicle passes by another vehicle just before a turning course (hereinafter, also referred to as passing by another vehicle just before a turning course) and a scene where a leading vehicle traveling in front of the vehicle itself changes lanes (hereinafter, also referred to as leading vehicle out).

[0007] The inventors of the present application also considered a situation specific to saddle riding vehicles in which the vehicle moves while changing its position in the lane width direction within the lane. It is conceivable that a saddle riding vehicle moves while changing its position in the lane width direction within the lane depending on the surrounding road conditions and the driving conditions of surrounding vehicles.

[0008] In light of the above, the inventors of the present application have come to propose an FCW device for saddle-ride type vehicles that takes into consideration the degree of freedom in positioning in the lane width direction that is specific to saddle-ride type vehicles, and that is capable of suppressing the recognition of nearby vehicles with a low probability of collision as obstacles and sounding an alarm in situations such as the above-mentioned passing just before a turning circle or when the preceding vehicle is out of position.

[0009] In the FCW control, generally, after detecting objects around the vehicle, an object that may collide with the vehicle is selected from the detected objects. Then, for example, the time to collision (TTC) between the selected object and the vehicle is calculated to determine whether or not to issue a warning to the driver of the vehicle. The FCW device executes multiple processes from the time the object is detected until the warning is issued to the driver. In a saddle-type vehicle, the space for mounting a device such as an FCW device is limited compared to a four-wheeled vehicle, so it is required to increase the design freedom of image processing hardware resources by reducing the load of various processes.

[0010] The inventors of the present application have investigated a configuration that detects the relative movement between the vehicle and surrounding vehicles using images captured by a monocular camera fixed to the vehicle body, selects vehicles to be warned without detecting white lines, and determines whether to issue a warning. As a result, they have found that it is possible to perform warning control that takes the above-mentioned situations into consideration while increasing the degree of freedom in designing hardware resources for image processing.

[0011] In the FCW device for a saddle-ride type vehicle according to the present disclosure, the following configuration is adopted in order to achieve both of the above-mentioned problems related to the saddle-ride type vehicle.

[0012] The FCW device for a straddle-type vehicle according to an embodiment of the present disclosure includes an alarm unit that issues an alarm to a driver, a self-vehicle path prediction that predicts the path of the self-vehicle, and a position detection of an object around the self-vehicle that detects the position of an object around the self-vehicle. The FCW device calculates the possibility of collision between the self-vehicle and the object using the result of the self-vehicle path prediction and the result of the position detection of the object around the self-vehicle, and executes an alarm control that controls the presence or absence of the alarm by the alarm unit based on the possibility of collision. The FCW device for a straddle-type vehicle is used in a straddle-type vehicle, and further includes a monocular camera that is fixed to the self-vehicle and images the periphery of the self-vehicle. The control unit calculates the time change of the relative position of the object detected by the position detection of the object around the self-vehicle in the captured image captured by the monocular camera with respect to the self-vehicle, and uses the results of the self-vehicle path prediction, the position detection of the object around the self-vehicle, and the time change of the relative position to execute the alarm control as described in each of the following situations. Situation 1: When the self-vehicle is traveling straight at a vehicle speed V1 on a road without a white line, and a first preceding vehicle is traveling straight in the same direction as the self-vehicle at a vehicle speed V2 (V2 < V1) that is smaller than the vehicle speed of the self-vehicle at a position that extends the center line in the vehicle width direction of the self-vehicle and in front of the self-vehicle, the control unit executes the alarm control so that an alarm is issued by the alarm unit when the possibility of collision between the self-vehicle and the first preceding vehicle becomes equal to or greater than a predetermined possibility of collision. Situation 2: When the self-vehicle is traveling straight at a vehicle speed V3 on a road without a white line, at a position that extends the center line in the vehicle width direction of the self-vehicle and in front of the self-vehicle, and when the second preceding vehicle is passing at a vehicle speed such that the relative speed with respect to the self-vehicle is the relative speed (V2 - V1) in Situation 1 at a position having the same inter-vehicle distance as the inter-vehicle distance between the self-vehicle and the first preceding vehicle when the alarm was issued by the alarm unit in Situation 1, the control unit executes the alarm control so that no alarm is issued by the alarm unit. Situation 3: In a situation where the relative position between the self-vehicle and the third preceding vehicle changes so as to change from Situation 3(a) described below to Situation 3(b), the control unit executes the alarm control so that no alarm is issued by the alarm unit. Situation 3(a): While the host vehicle is traveling straight at a vehicle speed V1 on a road without a white line, the third leading vehicle is at a position in front of the host vehicle where the center line in the vehicle width direction of the host vehicle is extended, and the position of the right end of the vehicle body of the third leading vehicle is the same as the position of the right end of the vehicle body of the host vehicle in the vehicle width direction. The third leading vehicle is traveling in the same direction as the host vehicle at a vehicle speed V2 (V2 < V1) that is smaller than the vehicle speed of the host vehicle, and the distance between the host vehicle and the third leading vehicle is greater than the distance between the host vehicle and the first leading vehicle when an alarm was issued by the alarm unit in Situation 1. Situation 3(b): When the third leading vehicle rotates its traveling direction 20 degrees to the right, and the right end of the vehicle body of the host vehicle is on the right side of the left end of the vehicle body of the third leading vehicle and on the left side of the center position in the vehicle body width direction of the third leading vehicle, the distance between the host vehicle and the third leading vehicle becomes the same as the distance between the host vehicle and the first leading vehicle when an alarm was issued by the alarm unit in Situation 1. The FCW device for a straddle-type vehicle is characterized in that it calculates the time change of the relative position of an object detected by detecting the position of an object around the host vehicle with respect to the host vehicle, and can execute different warning controls according to the host vehicle travel route prediction, the detection of the position of an object around the host vehicle, and the time change of the relative position. Due to this feature, when Situation 1 is reproduced, the FCW device for a straddle-type vehicle issues an alarm, and when Situations 2 and 3 are reproduced, the FCW device for a straddle-type vehicle does not issue an alarm. Situations 1, 2, and 3 are merely situation examples for showing the features of the FCW device for a straddle-type vehicle according to the present disclosure, and it is not intended to limit the warning control by the FCW device for a straddle-type vehicle to these situations.

[0013] In the above configuration, when the host vehicle is traveling straight at a vehicle speed V3 equal to the relative speed between the host vehicle and the second leading vehicle in Situation 1 on a road without a white line, and a fourth leading vehicle is stopped sideways with respect to the traveling direction of the host vehicle at a position that extends the center line in the vehicle width direction of the host vehicle and is in front of the host vehicle, the alarm control may be executed such that the alarm unit issues an alarm when the distance between the host vehicle and the fourth leading vehicle becomes the same as the distance between the host vehicle and the first leading vehicle when an alarm was issued by the alarm unit in Situation 1.

[0014] In the above configuration, in calculating the temporal change of the relative position, the control unit may obtain a movement vector from the difference in the detection coordinates of an object around the host vehicle in a plurality of captured images captured by the monocular camera, or may obtain a movement vector by optical flow.

[0015] An FCW method for a saddle-riding type vehicle according to an embodiment of the present disclosure includes a warning unit that issues a warning to a driver, a host vehicle path prediction that predicts the path of the host vehicle, and a position detection of an object around the host vehicle that detects the position of an object around the host vehicle, calculates the possibility of collision between the host vehicle and the object using the result of the host vehicle path prediction and the result of the position detection of the object around the host vehicle, and executes warning control that controls the presence or absence of a warning by the warning unit based on the possibility of collision. It is an FCW method for a saddle-riding type vehicle of an FCW device for a saddle-riding type vehicle, which is used in a saddle-riding type vehicle that tilts inward during turning, and includes a step of calculating a temporal change in the relative position of an object with respect to the host vehicle detected by the position detection of an object around the host vehicle in a captured image captured by a monocular camera fixed to the host vehicle and imaging the periphery of the host vehicle, and a step of executing the warning control as described in each of the following situations using the results of the host vehicle path prediction, the position detection of the object around the host vehicle, and the temporal change in the relative position. Situation 1: When the host vehicle is traveling straight at a vehicle speed V1 on a road without a white line, and a first preceding vehicle is traveling straight in the same direction as the host vehicle at a vehicle speed V2 (V2 < V1) that is smaller than the vehicle speed of the host vehicle at a position that extends the center line in the vehicle width direction of the host vehicle and in front of the host vehicle, the control unit executes the warning control so that a warning is issued by the warning unit when the possibility of collision between the host vehicle and the first preceding vehicle becomes equal to or greater than a predetermined possibility of collision. Situation 2: When the host vehicle is moving straight at a vehicle speed V3 on a road without a white line, at a position extending the center line in the vehicle width direction of the host vehicle and in front of the host vehicle, and at a position where the distance between the host vehicle and the second leading vehicle is the same as the distance between the host vehicle and the first leading vehicle when the warning was issued by the warning unit in the above Situation 1, and when the second leading vehicle is passing at a vehicle speed such that the relative speed with respect to the host vehicle is the relative speed (V2 - V1) in Situation 1, the control unit executes the warning control so that the warning by the warning unit is not issued. Situation 3: In a situation where the relative position between the host vehicle and the third leading vehicle changes so as to change from Situation 3(a) described below to Situation 3(b), the control unit executes the warning control so that the warning by the warning unit is not issued. Situation 3(a): When the host vehicle is moving straight at a vehicle speed V1 on a road without a white line, the third leading vehicle is at a position in front of the host vehicle extending the center line in the vehicle width direction of the host vehicle, and the position of the right end of the vehicle body of the third leading vehicle is the same as the position of the right end of the vehicle body of the host vehicle in the vehicle width direction, and is moving in the same direction as the host vehicle at a vehicle speed V2 (V2 < V1) smaller than the vehicle speed of the host vehicle, and the distance between the host vehicle and the third leading vehicle is greater than the distance between the host vehicle and the first leading vehicle when the warning was issued by the warning unit in the above Situation 1. Situation 3(b): The third leading vehicle rotates 20 degrees to the right in the traveling direction, and in a situation where the right end of the host vehicle is on the right side of the left end of the vehicle body of the third leading vehicle and on the left side of the center position in the vehicle body width direction of the vehicle body of the third leading vehicle, the distance between the host vehicle and the third leading vehicle becomes the same as the distance between the host vehicle and the first leading vehicle when the warning was issued by the warning unit in the above Situation 1.

[0016] In the above configuration, in the warning control, when the host vehicle is traveling straight on a road without white lines at a vehicle speed V3 equal to the relative speed between the host vehicle and the second preceding vehicle in situation 1, and a fourth preceding vehicle is stopped sideways to the direction of travel of the host vehicle at a position extended from the widthwise center line of the host vehicle and in front of the host vehicle, the warning unit may be configured to issue a warning when the inter-vehicle distance between the host vehicle and the fourth preceding vehicle becomes the same as the inter-vehicle distance between the host vehicle and the first preceding vehicle when the warning unit issued a warning in situation 1.

[0017] In the above configuration, in calculating the change over time in the relative position, a movement vector may be calculated from the difference in detection coordinates of objects around the vehicle in multiple images captured by the monocular camera, or the movement vector may be calculated using optical flow. Effect of the Invention

[0018] According to the FCW device for a saddle-riding type vehicle and the FCW method for a saddle-riding type vehicle of the present disclosure, it is possible to provide an FCW device for a saddle-riding type vehicle and an FCW method for a saddle-riding type vehicle that are capable of performing FCW control different from the conventional ones. [Brief description of the drawings]

[0019] [Figure 1] FIG. 1 is a diagram for explaining an overview of an FCW device for a saddle-ride type vehicle according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram for explaining the operation when a preceding vehicle is traveling ahead of the host vehicle. [Diagram 3] FIG. 3 is a diagram for explaining the operation when a preceding vehicle is traveling on a turning road in front of the host vehicle. [Figure 4] FIG. 4 is a diagram for explaining the operation when a preceding vehicle ahead of the host vehicle is traveling so as to deviate from the path of the host vehicle. [Diagram 5] FIG. 5 is a diagram for explaining the operation when there is a preceding vehicle that stops ahead of the host vehicle. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] Hereinafter, an embodiment of an FCW device for a saddle-riding type vehicle and an FCW method for a saddle-riding type vehicle according to the present invention will be described in detail with reference to the drawings. Prior to the description, terms used in the embodiment will be explained.

[0021] [Saddle-type vehicle] The saddle-type vehicle according to the present disclosure refers to any vehicle on which a driver rides astride a saddle. As viewed from the driver of the saddle-type vehicle, the right hand side is described as right, the left hand side is described as left, the front is described as front, and the rear is described as rear. The "own vehicle" described in the present disclosure refers to a saddle-type vehicle. The saddle-type vehicle includes a motorcycle. The saddle-type vehicle includes at least one front wheel and at least one rear wheel. For example, the saddle-type vehicle may have two front wheels and one or two rear wheels, or may have one front wheel and one or two rear wheels. The saddle-type vehicle may have a front wheel as a steering wheel, or a rear wheel as a steering wheel. The saddle-type vehicle runs by driving the driving wheels with a driving source. The driving source may be an internal combustion engine, an electric motor, or a hybrid driving source including an engine and an electric motor.

[0022] [FCW device for saddle-type vehicles] The FCW device for a saddle-type vehicle described in this disclosure includes an alarm unit, one or more control units, and a monocular camera.

[0023] [white line] The white lines described in this disclosure refer to lines drawn on the road to indicate the vehicle's travel lane, 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 roadway lines, shoulder strips, diagonal boundary lines, dividing lines, etc. The FCW device can execute 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 executed even on roads without white lines, and is not intended to limit the roads on which the saddle-type vehicle travels to roads without white lines.

[0024] [situation] In this disclosure, situations numbered and described, such as "Situation 1," indicate 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.

[0025] [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 saddle-type 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 handlebar 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 saddle-type vehicle may be used as an alarm device. An alarm targeting the sense of touch may be issued by vibrating at least one of the handlebar, the helmet, and the seat.

[0026] [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 saddle riding type vehicle is traveling, regardless of whether the saddle riding type 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.

[0027] [Monocular camera] The monocular camera described in this disclosure is an imaging device that captures images of the periphery of a saddle-type 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 saddle-type vehicle and used. The monocular camera can capture images of the road ahead on which the saddle-type vehicle is traveling. The monocular camera captures images of a preceding vehicle traveling ahead while the saddle-type vehicle is traveling straight or turning, a vehicle stopped or parked in front of the saddle-type 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 saddle-type vehicle are continuously captured.

[0028] [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 an image captured by a 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 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 saddle-riding vehicle is traveling straight, the FCW device can predict the path of the saddle-riding 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 saddle-riding vehicle. When the saddle-riding 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 saddle riding type vehicle is turning, the FCW device can predict the path of the turning saddle riding type vehicle by curvature correcting the predicted path on the captured image, which is obtained assuming that the saddle riding type vehicle is traveling straight, based on the detection result by the turning state detection unit. The FCW device can predict the path in approximately real time after acquiring the captured image by the monocular camera while the saddle riding type vehicle is traveling.

[0029] [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 saddle-type vehicle while the saddle-type vehicle is traveling straight or turning, a vehicle stopped or parked ahead of the saddle-type vehicle, 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 deviating from the predicted path. When a detected vehicle is described as a "preceding vehicle," it refers to a vehicle traveling ahead of the saddle-type vehicle in the same direction as the saddle-type 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.

[0030] [Calculation of time change in relative position between detected object and vehicle] The calculation of the time change in the relative position between the detected object and the vehicle (relative movement analysis) described in the present disclosure calculates the time change in the relative position between the vehicle and the object around the vehicle based on the result of position detection of the object around the vehicle obtained from multiple captured images captured by a monocular camera. For example, a movement vector is calculated from the difference between the detection coordinates based on the time history of the detection coordinates of the object around the vehicle in multiple captured images captured by the monocular camera. In addition, the calculation of the time change in the relative position may be calculated by calculating the movement vector using optical flow.

[0031] [Possibility of collision] The collision probability described in the present disclosure is a numerical value indicating the possibility of a collision between the saddle-riding vehicle and a surrounding object. For example, the relative movement speed of the object with respect to the saddle-riding vehicle, the distance between the saddle-riding vehicle and the object, the time until the saddle-riding vehicle collides with the object, and the like 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 between each detected object and the saddle-riding vehicle. For example, the distance from the object detected on the captured image to the saddle-riding 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 saddle-riding 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 saddle-riding 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.

[0032] [Passing each other just before the turning circle] As described in this disclosure, a passing just before a turning circle refers to a situation in which, when the vehicle is traveling straight and there is a turning circle ahead in the path, an oncoming vehicle comes from the turning circle toward the vehicle, and the oncoming vehicle is detected as a detected object ahead of the predicted path of the vehicle.

[0033] [Leading vehicle out] As described in the present disclosure, "preceding vehicle out" refers to a situation in which, when the host vehicle is traveling straight and there is a preceding vehicle ahead of the host vehicle's predicted path, the preceding vehicle moves to the right or left of the host vehicle's direction of travel at a predetermined angle relative to the host vehicle's direction of travel, and deviates from the host vehicle's predicted path.

[0034] [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 saddle-type vehicle equipped with the FCW device can be implemented by a person skilled in the art using the hardware configurations of devices and saddle-type vehicles known in prior art documents, other publicly known documents, and conventional technologies. Therefore, detailed descriptions of the hardware configurations of the FCW device and the saddle-type vehicle will be omitted.

[0035] [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.

[0036] An overview of the FCW device for a saddle-riding type vehicle according to this embodiment will be described with reference to Figures 1 to 5. Figure 1 is an explanatory diagram for explaining the overview of the FCW device for a saddle-riding type vehicle according to embodiment 1. As shown in Figure 1, the FCW device 2 for a saddle-riding type vehicle is provided on a saddle-riding type vehicle 1.

[0037] The FCW device 2 for a saddle-ride type vehicle includes an alarm unit 21, one or more control units 22, and a monocular camera .

[0038] The warning unit 21 issues a warning to the driver of the saddle riding type vehicle 1. The control unit 22 executes prediction of the course of the saddle riding type vehicle 1, i.e., the vehicle itself, detection of the positions of objects around the vehicle itself, and analysis of the relative movement between the vehicle itself and the objects around the vehicle itself. The control unit 22 calculates the possibility of collision using the results of the prediction of the vehicle's course, detection of the positions of objects around the vehicle itself, and analysis of the relative movement between the vehicle itself and the objects, and executes warning control to control whether or not the warning unit 21 issues a warning and the timing of issuing the warning based on the collision possibility. As shown in the dashed frame in Fig. 1, the FCW device 2 for a saddle riding type vehicle executes FCW control including object position detection, vehicle course prediction, analysis of the relative movement between the vehicle itself and the objects, and warning control.

[0039] Furthermore, the control unit 22 calculates the possibility of collision based on information such as the relative positional relationship between the host vehicle and the object around the host vehicle, the magnitude of the relative speed (magnitude of the movement vector), and the direction of the movement vector. When the calculated possibility of collision is smaller than a predetermined threshold, the control unit 22 excludes the object around the host vehicle from the object to be warned. Note that the control unit 22 may determine the exclusion from the object to be warned using the magnitude of the movement vector and the continuity of the direction of the movement vector in addition to the value of the possibility of collision. For example, the control unit 22 calculates the predicted path (extension of the movement vector) of the other vehicle based on time-series data of the position detection of the object around the host vehicle, and calculates the possibility of collision based on the distance between the predicted path and the position of the host vehicle (passing position) and the magnitude of the movement vector of the other vehicle.

[0040] Specifically, a Gaussian distribution is calculated with the passing position as the center and the inverse of the magnitude of the movement vector of the other vehicle as the standard deviation, and the integral value of the overlap between the Gaussian distribution and the vehicle width of the vehicle is calculated as the collision probability. Based on the collision probability, the control unit 22 determines whether or not to exclude the other vehicle from the warning target. Note that the method of calculating the collision probability is not limited to the above method, and for example, a mapping may be stored in advance in which the passing position and the magnitude and direction of the movement vector of the other vehicle are input information and the collision probability is output information.

[0041] A monocular camera 23 fixed to the body of the saddle riding type vehicle 1 captures images of the surroundings of the vehicle including the area ahead of the saddle riding type vehicle 1. The control unit 22 acquires (A) the captured images captured by the monocular camera 23. The control unit 22 executes (B) position detection of objects around the vehicle and (C) vehicle path prediction based on the acquired captured images.

[0042] The control unit 22 performs a relative movement analysis (D) between the host vehicle and the object based on the result obtained by executing the position detection of the object around the host vehicle and the result obtained by executing the vehicle path prediction, and can execute warning control (E) in situations 1, 2, and 3 shown in Fig. 1 based on the result of executing the relative movement analysis between the host vehicle and the object. Here, the relative movement analysis performs object position detection around the host vehicle to obtain detection coordinates, and calculates a movement vector (direction and magnitude) from the difference between the detection coordinates of the obtained time-series data of the detection coordinates. The movement vector may be calculated from the optical flow of an image captured by a monocular camera.

[0043] Situation 1, Situation 2, and Situation 3 shown in FIG. 1 are the positional relationship between the straddle-type vehicle 1 in motion and the preceding vehicles 101 to 103 detected by detecting the positions of the objects around the host vehicle, viewed from above, the predicted path of the straddle-type vehicle 1 obtained by performing host vehicle path prediction, and the result of relative movement analysis between the preceding vehicle and the host vehicle. The dashed-dotted line indicates the predicted path of the straddle-type vehicle 1 obtained by performing host vehicle path prediction. The broken line indicates the path through which both ends in the vehicle width direction of the straddle-type vehicle 1 pass when the straddle-type vehicle 1 travels along the obtained predicted path. The arrows attached to the preceding vehicles 101 to 103 indicate the moving directions of the preceding vehicles. If there is an object in the belt-shaped area indicated by the two broken lines, there is a possibility of collision between this object and the straddle-type vehicle 1 when the straddle-type vehicle 1 travels along the predicted path. Based on the relative movement analysis between the preceding vehicle and the host vehicle, when there is a high possibility of collision between the straddle-type vehicle 1 and the preceding vehicle when the straddle-type vehicle 1 travels along the predicted path, the warning unit 21 is controlled to issue a warning, and when there is a low possibility of collision with the preceding vehicle, the warning unit 21 is controlled not to issue a warning. Such warning control is executed by the control unit 22.

[0044] In Situation 1, while the host vehicle is traveling straight at a vehicle speed V1 on a road without a white line, the first preceding vehicle 101 is traveling straight in the same direction as the host vehicle at a vehicle speed V2 (V2 < V1), which is lower than the vehicle speed of the host vehicle, at a position extending the center line in the vehicle width direction of the host vehicle and in front of the host vehicle.

[0045] In Situation 1, when the possibility of collision between the straddle-type vehicle 1 and the first preceding vehicle 101 becomes equal to or higher than a predetermined collision possibility, the control unit 22 executes warning control to issue a warning. For example, as shown in FIG. 2(a), at time t = t1, when the distance d between the straddle-type vehicle 1 and the preceding vehicle 101 is longer than the distance Da for issuing a warning at a predetermined relative speed Vr (V1 - V2), the control unit 22 executes warning control not to issue a warning by the warning unit 21.

[0046] On the other hand, as shown in FIG. 2(b), at time t = t2 (t2 > t1), when the distance d between the straddle-type vehicle 1 and the preceding vehicle 101 becomes equal to or shorter than Da, the control unit 22 executes warning control to control the warning unit 21 to issue a warning.

[0047] In situation 2, while the host vehicle is traveling straight on a road without white lines at vehicle speed V3, the second leading vehicle 102 is traveling so as to pass a position which is an extension of the center line in the vehicle width direction of the host vehicle, which is in front of the host vehicle, and which provides a similar inter-vehicle distance to the host vehicle and the first leading vehicle when the alarm was issued by the alarm unit in situation 1, at a relative speed (V2-V1) with respect to the host vehicle. Also, the movement vector in the traveling direction of the second leading vehicle 102 has an angle of 110° with respect to the traveling direction of the host vehicle.

[0048] In situation 2, the control unit 22 executes warning control to control the warning unit 21 so as not to issue a warning for the second leading vehicle 102. For example, as shown in Fig. 3(a), at time t = t1, the saddle riding type vehicle 1 is traveling straight. The second leading vehicle 102, which has come out of a turning path, is present on the predicted path of the saddle riding type vehicle 1. In this case, the distance d between the vehicle and the second leading vehicle 102 is longer than the distance Da at which a warning is issued, so the control unit 22 controls the warning unit 21 so as not to issue a warning.

[0049] As shown in FIG. 3(b), at time t=t2 (t2>t1), the distance d between the saddle riding type vehicle 1 and the second leading vehicle 102 becomes equal to or shorter than Da. In FIG. 3(a) and FIG. 3(b), an analysis result is obtained by analyzing the relative movement between the saddle riding type vehicle 1 and the second leading vehicle 102, which indicates that the second leading vehicle 102 is moving at a movement vector angle of 110° with the traveling direction of the saddle riding type vehicle 1. Based on the obtained analysis result, the control unit 22 controls the warning unit 21 not to issue a warning targeting the second leading vehicle 102. That is, in FIG. 3(b), the control unit 22 executes warning control so that the warning unit 21 does not issue a warning even if the second leading vehicle 102 is traveling at the same relative speed and at the same distance as when the warning was issued in situation 1.

[0050] In situation 3 shown in FIG. 1, assume a scene where the situation changes from situation 3(a) described below to situation 3(b). In situation 3(a), while the host vehicle is moving straight ahead at vehicle speed V1 on a road without a white line, the third leading vehicle 103 is at a position in front of the host vehicle that extends the center line in the vehicle width direction, and the position of the right end of the body of the third leading vehicle is the same as the position of the right end of the body of the host vehicle in the vehicle width direction, and is traveling in the same direction as the host vehicle at a vehicle speed V2 (V2 < V1) that is smaller than the vehicle speed of the host vehicle. Further, at this time, the distance between the host vehicle and the third leading vehicle 103 is greater than the distance between the host vehicle and the first leading vehicle 101 when the alarm was issued by the alarm unit 21 in situation 1.

[0051] In situation 3(b), the third leading vehicle 103 rotates its traveling direction 20 degrees to the right, and in a situation where the right end of the body of the host vehicle is on the right side of the left end of the body of the third leading vehicle and on the left side of the center position in the vehicle width direction of the body of the third leading vehicle 103, the distance between the host vehicle and the third leading vehicle 103 becomes the same inter-vehicle distance as the distance between the host vehicle and the first leading vehicle 101 when the alarm was issued by the alarm unit 21 in situation 1. The control unit 22 controls the alarm unit 21 so as not to issue an alarm in situation 3. For example, as shown in FIG. 4(a), at time t = t1, the straddle-type vehicle 1 is moving straight ahead. And on the predicted travel path of the straddle-type vehicle 1, the third leading vehicle 103 is traveling with an angle formed by the traveling direction of the straddle-type vehicle 1 and the movement vector angle of 20°.

[0052] On the other hand, as shown in FIG. 4(b), at time t = t2 (t2 > t1), the distance d between the straddle-type vehicle 1 and the third leading vehicle 103 becomes equal to or shorter than Da. In FIGS. 4(a) and 4(b), as a result of the relative movement analysis between the straddle-type vehicle 1 and the third leading vehicle 103, it is obtained as an analysis result showing that the third leading vehicle 103 is traveling with a movement vector angle of 20° with respect to the traveling direction of the straddle-type vehicle 1. Based on the obtained analysis result, the control unit 22 executes alarm control not to issue an alarm targeting the third leading vehicle 103. That is, in FIG. 4(b), even when the third leading vehicle 103 is traveling at the same relative speed and at the same distance as when the alarm was issued in situation 1, the control unit 22 executes alarm control so that the alarm unit 21 does not issue an alarm.

[0053] Next, the operation of the FCW device for a saddle riding type vehicle when a leading vehicle 201 is stopped in front of the saddle riding type vehicle 1 will be described. Fig. 5 is a diagram for explaining the operation when there is a fourth leading vehicle 201 that is stopped in front of the host vehicle. As shown in Fig. 5, while the host vehicle is traveling straight on a road without white lines, the fourth leading vehicle 201 is stopped at a position in front of the host vehicle as an extension of the center line in the vehicle width direction. As shown in Fig. 5, the fourth leading vehicle 201 is stopped sideways with respect to the traveling direction of the host vehicle.

[0054] The control unit 22 executes warning control so that the warning unit 21 issues a warning when the saddle-type vehicle 1 is traveling at a vehicle speed V1-V2 and the distance d between the saddle-type vehicle 1 and the stopped fourth preceding vehicle 201 becomes equal to or shorter than Da.

[0055] In this way, the FCW device 2 for a saddle riding type vehicle predicts the course of the saddle riding type vehicle 1, and controls the warning unit 21 to issue a warning when the possibility of a collision with an object on the predicted course reaches a predetermined probability of collision. In other words, the FCW device 2 for a saddle riding type vehicle does not issue a warning for an object that is not on the predicted course. As shown in Situations 2 and 3, even if there is a preceding vehicle ahead of the predicted course of the saddle riding type vehicle 1, the FCW device 2 for a saddle riding type vehicle can exclude the preceding vehicle from the target of warning for a forward collision based on the analysis result of the relative movement analysis between the saddle riding type vehicle 1 and the preceding vehicle.

[0056] The FCW device 2 for a saddle riding type vehicle issues an alarm when an object approaching the saddle riding type vehicle 1 due to the movement of the saddle riding type vehicle 1 or due to relative movement between the saddle riding type vehicle 1 and the object is on the predicted path of the saddle riding type vehicle 1, but does not issue an alarm when the object is expected to deviate from the predicted path of the vehicle. Situations 1, 2, and 3 are examples to illustrate this, and the alarm control by the FCW device 2 for a saddle riding type vehicle is not limited to situations 1, 2, and 3.

[0057] 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]

[0058] The FCW device for a saddle-ride type vehicle and the FCW method for a saddle-ride type vehicle according to the present invention are suitable for cases where FCW control different from the conventional ones is performed. [Explanation of symbols]

[0059] 1 Saddle-type vehicle 2 FCW device for saddle-type vehicles 21 Alarm section 22 Control section 23 Monocular Camera 101 First advance vehicle 102 2nd Leading Vehicle 103 Third Leading Vehicle 201 4th Leading Vehicle

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 FCW device for a saddle-type vehicle used in a saddle-type vehicle, A monocular camera that is fixed to the vehicle and captures images of the surroundings of the vehicle. Further equipped with The control unit is Calculating a time change in a relative position of an object detected in the position detection of the object around the host vehicle in an image captured by the monocular camera with respect to the host vehicle, and Using the results of the vehicle trajectory prediction, the position detection of the object around the vehicle, and the time change of the relative position, the warning control is executed as described in each of the following situations. FCW device for a saddle-type vehicle. Situation 1: When the host vehicle is traveling straight at a vehicle speed V1 on a road without white lines, and a first preceding vehicle is traveling straight in the same direction as the host vehicle at a position extended from the vehicle width centerline of the host vehicle and in front of the host vehicle at a vehicle speed V2 (V2 < V1) that is slower than the vehicle speed of 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 possibility of collision. Situation 2: When the vehicle is traveling straight at a vehicle speed V3 on a road without white lines, and a second preceding vehicle is passing a position that is an extension of the vehicle width centerline of the vehicle, is in front of the vehicle, and is at a position where the distance between the vehicle and the first preceding vehicle is the same as the distance between the vehicle and the first preceding vehicle when the alarm was issued by the alarm unit in situation 1, the control unit executes the alarm control so that the alarm unit does not issue an alarm. Situation 3: In a situation in which the relative position between the host vehicle and a third preceding vehicle changes from situation 3(a) to situation 3(b) described below, the control unit executes the warning control so that the warning unit does not issue a warning. Situation 3 (a): While the host vehicle is traveling straight on a road without white lines at the vehicle speed V1, the third preceding vehicle is located ahead of the vehicle width centerline of the host vehicle, and is traveling in the same direction as the host vehicle at a vehicle speed V2 (V2 < V1) that is slower than the vehicle speed of the host vehicle, at a position where the position of the right end of the third preceding vehicle is the same as the position of the right end of the host vehicle in the vehicle width direction, and the inter-vehicle distance between the host vehicle and the third preceding vehicle is greater than the inter-vehicle distance between the host vehicle and the first preceding vehicle when the alarm was issued by the alarm unit in situation 1. Situation 3 (b): When the third preceding vehicle rotates its direction of travel by 20 degrees to the right, and the right end of the host vehicle's body is to the right of the left end of the third preceding vehicle's body and to the left of the center position of the third preceding vehicle's body in the width direction, the inter-vehicle distance between the host vehicle and the third preceding vehicle becomes the same as the inter-vehicle distance between the host vehicle and the first preceding vehicle when the alarm was issued by the alarm unit in situation 1.

2. The control unit is when the host vehicle is traveling straight on a road without white lines at a vehicle speed V3 equal to the relative speed between the host vehicle and the second preceding vehicle in the situation 1, and a fourth preceding vehicle is stopped laterally with respect to the traveling direction of the host vehicle at a position on an extension of a center line in a vehicle width direction of the host vehicle and in front of the host vehicle, the warning control is executed so that the warning unit issues a warning when the inter-vehicle distance between the host vehicle and the fourth preceding vehicle becomes the same as the inter-vehicle distance between the host vehicle and the first preceding vehicle when the warning unit issued a warning in the situation 1.

2. The FCW device for a straddle-type vehicle according to claim 1.

3. The control unit is In calculating the change over time of the relative position, a movement vector is calculated from a difference between detection coordinates of the object around the vehicle in a plurality of captured images taken by the monocular camera, or the movement vector is calculated by optical flow.

2. The FCW device for a straddle-type vehicle according to claim 1.

4. 1. An FCW method for a saddle-ride type vehicle, 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, A step of calculating a time change in a relative position of an object detected in a position detection of the object around the host vehicle in an image captured by a monocular camera fixed to the host vehicle for capturing an image of the surroundings of the host vehicle; Executing the warning control as described in each of the following situations using the results of the host vehicle trajectory prediction, the position detection of the object around the host vehicle, and the time change of the relative position. The FCW method for a saddle-type vehicle includes: Situation 1: When the host vehicle is traveling straight at a vehicle speed V1 on a road without white lines, and a first preceding vehicle is traveling straight in the same direction as the host vehicle at a position extended from the vehicle width centerline of the host vehicle and in front of the host vehicle at a vehicle speed V2 (V2 < V1) that is slower than the vehicle speed of 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 vehicle is traveling straight at a vehicle speed V3 on a road without white lines, and a second preceding vehicle is passing a position that is an extension of the vehicle width centerline of the vehicle, is in front of the vehicle, and is at a position where the distance between the vehicle and the first preceding vehicle is the same as the distance between the vehicle and the first preceding vehicle when the alarm was issued by the alarm unit in situation 1, the control unit executes the alarm control so that the alarm unit does not issue an alarm. Situation 3: In a situation where the relative position between the vehicle and the third preceding vehicle changes from situation 3(a) described below to situation 3(b), the control unit executes the warning control so that the warning unit does not issue a warning. Situation 3 (a): While the host vehicle is traveling straight on a road without white lines at a vehicle speed V1, the third preceding vehicle is located ahead of the host vehicle's vehicle width direction center line, and is traveling in the same direction as the host vehicle at a vehicle speed V2 (V2 < V1) that is slower than the vehicle speed of the host vehicle, at a position where the position of the right end of the third preceding vehicle is the same as the position of the right end of the host vehicle in the vehicle width direction, and the inter-vehicle distance between the host vehicle and the third preceding vehicle is greater than the inter-vehicle distance between the host vehicle and the first preceding vehicle when the alarm was issued by the alarm unit in situation 1. Situation 3 (b): When the third preceding vehicle rotates its direction of travel by 20 degrees to the right, and the right end of the host vehicle's body is to the right of the left end of the third preceding vehicle's body and to the left of the center position of the third preceding vehicle's body in the width direction, the inter-vehicle distance between the host vehicle and the third preceding vehicle becomes the same as the inter-vehicle distance between the host vehicle and the first preceding vehicle when the alarm was issued by the alarm unit in situation 1.

5. In the warning control, when the host vehicle is traveling straight on a road without white lines at a vehicle speed V3 equal to the relative speed between the host vehicle and the second preceding vehicle in the situation 1, and a fourth preceding vehicle is stopped sideways with respect to the traveling direction of the host vehicle at a position on an extension of a center line in the vehicle width direction of the host vehicle and in front of the host vehicle, the warning unit issues a warning when the inter-vehicle distance between the host vehicle and the fourth preceding vehicle becomes the same as the inter-vehicle distance between the host vehicle and the first preceding vehicle when the warning unit issued a warning in the situation 1.

5. The FCW method for a saddle-type vehicle according to claim 4.

6. In calculating the change over time of the relative position, a movement vector is calculated from a difference between detection coordinates of the object around the vehicle in a plurality of captured images taken by the monocular camera, or the movement vector is calculated by optical flow.

5. The FCW method for a saddle-type vehicle according to claim 4.

Images