JP5018571B2 - Deceleration instruction device and deceleration instruction method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a device for urging a driver to take a safety measure when there are a plurality of warning objects ahead of his or her own vehicle. <P>SOLUTION: A deceleration instruction device is provided with: a decision time determining means for determining a decision time; a projecting means for projecting an image onto a road surface ahead of one's own vehicle; a warning object information output means for outputting a position of the warning object and a relative moving speed ahead of one's own vehicle; an arrival time calculating means for calculating an arrival time required for one's own vehicle to arrive at each warning object on the basis of a position of each warning object and a relative moving speed when a plurality of positions of warning objects and the relative moving speed are output; a time interval predicting means for predicting time intervals at which one's own vehicle passes each warning object from each arrival time calculated; and a projection control means for projecting an image for instructing deceleration onto the road surface ahead of one's own vehicle by the projecting means when at least one of the predicted time intervals is shorter than the decision time determined by the decision time determining means. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a deceleration instruction device and a deceleration instruction method for instructing a driver to decelerate according to a situation ahead of a traveling vehicle.

There is a technique for notifying the driver of the presence of a target object in front of the host vehicle while traveling. A target of attention is a target that requires attention when traveling. Examples of caution objects include pedestrians, bicycles, parked vehicles, intersections, obstacles, and the like.
Patent Document 1 discloses a technique for detecting the presence of an attention object (a pedestrian in Patent Document 1) ahead of the host vehicle and irradiating the detected attention object with spot light. By irradiating the attention object with the spot light, the driver can recognize the attention object. Therefore, the driver can safely drive the host vehicle without overlooking the attention object.

JP 2006-176020 A

As in the technique of Patent Document 1, the technique of irradiating the attention object with spot light causes a problem when a plurality of attention objects exist in front of the host vehicle.
For example, if spot light is irradiated in order to each attention object, spot light will be irradiated to the front of the own vehicle intricately. Therefore, the driver's consciousness is distracted. In addition, it becomes difficult for the driver to recognize all the attention objects. In addition, even if the driver can recognize all the attention objects, if a plurality of information is given to the driver in this manner, it is difficult for the driver to properly determine the information and perform the driving. Become.
In addition, when there are multiple caution objects in front of the host vehicle, the target object near the host vehicle is irradiated with spot light, and when passing the target object, spot light is irradiated to the next target object. Irradiation is also conceivable. According to this method, the driver can easily recognize the attention object. However, when the spot light is irradiated in this manner, a problem occurs when two attention objects are close to each other. That is, when spot light is irradiated to the second attention object at the time of passing through the first attention object, the second attention object is already approaching when the spot light is irradiated, and the driver cannot appropriately deal with it. there is a possibility.
As described above, in the conventional technology, it is difficult for the driver to drive the host vehicle safely when there are a plurality of attention objects ahead of the host vehicle.

  The present invention has been made in view of the above-described circumstances, and provides a device that can prompt a driver to take a safe action when a plurality of attention objects are present in front of the host vehicle. Objective.

Even when there are a plurality of attention objects in front of the host vehicle, the inventor pays attention to each attention object and makes an appropriate determination when passing each attention object at a sufficiently long time interval. Focused on the fact that it is possible. That is, when passing through a plurality of attention objects at short time intervals, it is difficult for the driver to accurately recognize each attention object and often makes a mistake.
Therefore, this invention provides the deceleration instruction | indication apparatus which instruct | indicates deceleration to a driver | operator according to the condition ahead of the own vehicle in driving | running | working. The deceleration instruction apparatus includes a determination time determining unit, a projecting unit, an attention object information output unit, an arrival time calculating unit, a time interval predicting unit, and a projection control unit. The determination time determining means determines the determination time. The projecting means projects an image on the road surface ahead of the host vehicle. The attention object information output means specifies and outputs the position of the attention object in front of the host vehicle and the relative movement speed. The arrival time calculation means determines whether the own vehicle is cautioned on the basis of the output positions and relative movement speeds of the respective attention objects when the attention object information output means outputs the positions and relative movement speeds of the plurality of attention objects. The arrival time required to reach the target is calculated. The time interval prediction means predicts a time interval at which the host vehicle passes through each attention object from each arrival time calculated by the arrival time calculation means. The projection control unit instructs the projection unit to decelerate the road surface ahead of the host vehicle when at least one of the time intervals predicted by the time interval prediction unit is shorter than the determination time determined by the determination time determination unit. Project an image.
The relative movement speed refers to a relative movement speed with respect to the subject vehicle. When the attention object is a stationary object (an object whose absolute movement speed is zero), the traveling speed of the host vehicle can be adopted as the relative movement speed of the attention object.
In this deceleration instruction device, when there are a plurality of attention objects ahead of the host vehicle, the attention object information output means outputs the positions and relative movement speeds of the plurality of attention objects. Then, the arrival time calculating means and the time interval predicting means are operated to predict the time interval at which the host vehicle passes through each attention object. When there are three or more attention objects, “the time interval from passing through the first attention object to passing through the second attention object, and the third time after passing through the second attention object” A plurality of time intervals are predicted, such as “Time interval until passing the attention object... When at least one of the predicted time intervals is shorter than the determination time, an image instructing deceleration is projected in front of the host vehicle by the projection unit. Therefore, when the predicted time interval is shorter than the determination time, the driver can reduce the traveling speed of the host vehicle by looking at the projected image. By reducing the traveling speed of the host vehicle, the actual time interval passing through each attention object becomes longer than the predicted time interval, and the driver can drive with appropriate attention to each attention object. It becomes possible.
Thus, in the deceleration instruction device according to the present invention, when there are a plurality of attention objects ahead of the host vehicle, the attention objects are not individually notified to the driver, but the presence of the attention objects is not individually notified to the driver. The driver is instructed to decelerate when the time interval passing through is short. That is, the driver is informed of one piece of information called a deceleration instruction. Therefore, the driver can appropriately decelerate the host vehicle without hesitation in the determination. After decelerating, sufficient attention can be paid to each cautionary object, so that it is possible to drive safely. Further, the instruction for deceleration is performed by projecting an image on the road surface ahead of the host vehicle. Therefore, the driver can confirm the instruction of deceleration without moving the viewpoint or focus.
Note that the above-described “determination time” needs to be set to a time longer than the time interval at which the driver can surely recognize each attention object when the host vehicle passes through the plurality of attention objects. The determination time may be set to a constant value (that is, the determination time determination means may always output a predetermined determination time). Note that the determination time varies depending on the age and sex of the driver. The determination time may be set by the driver himself or may be set in advance by the manufacturer. In addition, the determination time also changes depending on the driving situation (the situation around the host vehicle and the situation of the driver). Therefore, the determination time determining means may change the determination time according to the situation at the time of traveling.

In the deceleration instruction device described above, the attention object information output means includes an image acquisition means, a pedestrian position specifying means, a pedestrian position storage means, a pedestrian relative movement speed specifying means, and an approaching pedestrian information output means. It is preferable. The image acquisition means acquires an image ahead of the host vehicle. The pedestrian position specifying unit specifies the position of the pedestrian from the image acquired by the image acquisition unit. The pedestrian position storage means stores the position of the pedestrian specified by the pedestrian position specifying means. The pedestrian relative movement speed specifying means is based on the pedestrian's past position stored by the pedestrian position storage means and the pedestrian's current position specified by the pedestrian position specifying means. Is identified. The approaching pedestrian information output means calculates the planned travel range of the host vehicle from the current position of the pedestrian specified by the pedestrian position specifying means and the relative movement speed of the pedestrian specified by the pedestrian relative movement speed specifying means. The position and relative movement speed of a pedestrian who may enter the road are specified and output.
In the present specification, “pedestrian” is a concept including a running bicycle. That is, the “pedestrian” includes both “a person walking” and “a person riding a bicycle”.
According to such a configuration, it is possible to specify a pedestrian who may enter the scheduled travel range of the host vehicle as a caution target.

In the deceleration instruction device described above, the attention object information output means includes a travel speed detection means, a map data storage means, a GPS signal reception means, a host vehicle position calculation means, an intersection position specification means, and an intersection information output means. It is preferable to provide. The travel speed detection means detects the travel speed of the host vehicle. The map data storage means stores map data. The GPS signal receiving means receives a GPS signal. The own vehicle position calculating means calculates the position of the own vehicle from the GPS signal received by the GPS signal receiving means. The intersection position specifying means specifies the position of the intersection existing ahead of the host vehicle from the map data stored in the map data storage means and the position of the host vehicle calculated by the host vehicle position calculating means. The intersection information output means outputs the position of the intersection specified by the intersection position specifying means and the traveling speed detected by the traveling speed detecting means.
Since the intersection is a stationary object, the traveling speed of the own vehicle detected by the traveling speed detecting means is a relative movement speed of the intersection with respect to the own vehicle.
According to such a configuration, the intersection can be specified as the attention object.

In the deceleration instruction device described above, the attention object information output means includes a travel speed detection means, an image acquisition means, another vehicle position specification means, another vehicle position storage means, another vehicle relative movement speed specification means, and a parked vehicle. It is preferable to include a position specifying means and a parked vehicle information output means. The travel speed detection means detects the travel speed of the host vehicle. The image acquisition means acquires an image ahead of the host vehicle. The other vehicle position specifying means specifies the position of the other vehicle in front of the host vehicle from the image acquired by the image acquisition means. The other vehicle position storage means stores the position of the other vehicle specified by the other vehicle position specifying means. The other vehicle absolute movement speed specifying means is detected by the past position of the other vehicle stored in the other vehicle position storage means, the current position of the other vehicle specified by the other vehicle position specifying means, and the traveling speed detection means. The absolute moving speed of the other vehicle is specified from the travel speed thus determined. The parked vehicle position specifying means specifies the position of the parked vehicle based on the position of the other vehicle specified by the other vehicle position specifying means and the absolute movement speed of the other vehicle specified by the other vehicle absolute movement speed specifying means. . The parked vehicle information output means outputs the position of the parked vehicle specified by the parked vehicle position specifying means and the travel speed detected by the travel speed detecting means.
Since the parked vehicle is a stationary object, the travel speed of the host vehicle detected by the travel speed detecting means is a relative movement speed of the parked vehicle with respect to the host vehicle.
According to such a configuration, the parked vehicle can be specified as the attention object.

In addition, even when the time interval for passing through a plurality of attention objects is short, if the short time interval is not continuous (that is, the section between the attention objects passing at a short time interval is not continuous), driving In many cases, the person can recognize each attention object relatively accurately.
Therefore, it is preferable that the deceleration instruction device described above further includes a time interval maximum number storage unit that stores the maximum time interval number. The projection control unit preferably projects the image by the projection unit when the number of consecutive sections between the attention objects passing at a time interval shorter than the determination time is greater than the maximum number of time intervals.
According to such a configuration, no image is projected when the number of consecutive sections between attention objects passing at a time interval shorter than the determination time is equal to or less than the maximum number of time intervals. An image for instructing deceleration is not projected on the road surface until the attention object can be accurately recognized.
The “maximum number of time intervals” described above needs to be a number that allows the driver to accurately recognize each attention object. The maximum number of time intervals varies depending on the driver's age and gender. The maximum number of time intervals may be set by the driver himself or may be set in advance by the manufacturer.

The present invention also provides a deceleration instruction method for instructing the driver to decelerate according to the situation ahead of the traveling vehicle. This deceleration instruction method includes an apparatus including an attention object information output unit that specifies and outputs a position and a relative movement speed of an attention object in front of the host vehicle, and a projection unit that projects an image on a road surface in front of the host vehicle. Use to command deceleration. This deceleration instruction method includes a step of determining a determination time, and when the positions and relative movement speeds of a plurality of attention objects are output by the attention object information output means, the positions and relative movement speeds of the respective attention objects are output. A step of calculating an arrival time required for the host vehicle to reach each attention object, a step of predicting a time interval for the host vehicle to pass each attention object from the calculated arrival times, and a predicted time When at least one of the intervals is shorter than the determined determination time, the projector includes a step of projecting an image instructing deceleration on the road surface ahead of the host vehicle.
According to this deceleration instruction method, when there are a plurality of attention objects ahead of the host vehicle, the driver can be encouraged to take a safe action.

  According to the deceleration instruction device of the present invention, when there are a plurality of caution objects in front of the host vehicle and it is difficult for the driver to accurately recognize each caution object, the driver decelerates. Can be instructed. Therefore, the driver can drive safely without making a mistake even when there are a plurality of attention objects ahead of the host vehicle.

The main features of the embodiments described in detail below are listed first.
(Characteristic 1) The attention object information output means is an accompaniment from the position of each pedestrian specified by the pedestrian position specifying means and the relative movement speed of each pedestrian specified by the pedestrian relative movement speed specifying means. Identify a pedestrian. And an approaching pedestrian specific means performs a process by making into a single pedestrian the some pedestrian who is the accompanying body specified by the accompanying body specific means.
(Feature 2) Projection start time storage means for storing the projection start time is further provided. When the projection control means has more than the maximum number of time intervals between the attention objects that pass at a time interval shorter than the determination time, the host vehicle is the first in the attention object group included in the continuous intervals. When the arrival time to reach the attention object that arrives (that is, the attention object that reaches the earliest) is shorter than the projection start time, the projection unit projects an image instructing deceleration on the road surface ahead of the host vehicle.

  Embodiments of the deceleration instruction device of the present invention will be described with reference to the drawings. FIG. 1 shows a schematic configuration of a deceleration instruction device 10 of the present embodiment that is mounted on an automobile 100. Hereinafter, the automobile 100 is referred to as the host vehicle 100. While the host vehicle 100 is traveling, the deceleration instruction device 10 projects an image instructing deceleration on the road surface in front of the host vehicle 100 according to the situation in front of the host vehicle 100. As shown in FIG. 1, the deceleration instruction device 10 includes two cameras 12a and 12b, a car navigation system 14, a speed sensor 16, a steering angle sensor 18, and two projection display devices 20a and 20b. The driver photographing camera 21a, the rain sensor 21b, the light receiving sensor 21c, the storage device 22, and the arithmetic device 24 are provided.

  The cameras 12a and 12b are installed at positions where the front of the host vehicle 100 can be photographed. The camera 12a is attached to the right side of the host vehicle 100. The camera 12b is attached to the left side of the host vehicle 100. The cameras 12a and 12b take images in front of the host vehicle 100 in real time. The cameras 12a and 12b are connected to the arithmetic device 24. Image data captured by the cameras 12a and 12b is input to the arithmetic unit 24.

  The car navigation system 14 (hereinafter simply referred to as the car navigation system 14) includes a main body including a display, a calculation device, a storage device, and the like, a GPS antenna, and the like. Reference numeral 14 in FIG. 1 indicates the position of the main body of the car navigation system 14. As shown in FIG. 1, the main body of the car navigation system 14 is installed near the driver's seat. FIG. 2 is a block diagram showing a detailed structure of the deceleration instruction device 10. As shown in FIG. 2, among the constituent members of the car navigation system 14, the map data storage unit 14 a, the host vehicle position calculation unit 14 b, and the GPS antenna 14 c function as part of the deceleration instruction device 10. The map data storage unit 14a is configured by a storage area that stores map data in the storage device of the car navigation system 14. The GPS antenna 14c is an antenna that receives a GPS signal transmitted from an artificial satellite or the like. The GPS signal received by the GPS antenna 14c is input to the host vehicle position calculation unit 14b. The own vehicle position calculation unit 14 b is configured by an arithmetic device mounted on the main body of the car navigation system 14. The own vehicle position calculation unit 14b calculates the position (absolute coordinates) of the own vehicle 100 from the GPS signal input from the GPS antenna 14c. In addition, the host vehicle position calculation unit 14 b calculates the traveling direction of the host vehicle 100 from the past position data of the host vehicle 100 and the current position data of the host vehicle 100. As shown in FIG. 2, the map data storage unit 14 a and the host vehicle position calculation unit 14 b are connected to the calculation device 24. The map data stored in the map data storage unit 14a and the position data and traveling direction data of the host vehicle 100 calculated by the host vehicle position calculation unit 14b are input to the arithmetic unit 24.

  The speed sensor 16 detects the traveling speed of the host vehicle 100. The speed sensor 16 is connected to the arithmetic device 24. The traveling speed data detected by the speed sensor 16 is input to the arithmetic device 24.

  The steering angle sensor 18 detects the steering angle of the steering wheel of the host vehicle 100. The steering angle sensor 18 is connected to the calculation device 24. The steering angle data detected by the steering angle sensor 18 is input to the arithmetic unit 24.

The projection display devices 20a and 20b are installed at the forefront of the host vehicle 100 (side the headlight). The projection display devices 20 a and 20 b are connected to the arithmetic device 24. The projection display devices 20 a and 20 b project an image onto the road surface ahead of the host vehicle 100 in response to a command from the arithmetic device 24. By operating both the projection display device 20a and the projection display device 20b, one image is projected onto the road surface. That is, the projection display device 20a and the projection display device 20b substantially function as a single projection display device for projecting one image. Therefore, hereinafter, the projection display device 20a and the projection display device 20b are collectively referred to as a projection display device 20.
The projection display device 20 may be a device that projects an image by an imaging method such as a projector. The laser beam may be raster-scanned, or the laser beam may be vector-scanned. The light source is not limited, and may be a laser, an ultrahigh pressure mercury lamp, a halogen lamp, or the like. In the present embodiment, an example is shown in which one image is projected by the two projection display devices 20a and 20b, but the left and right images may be projected respectively. Further, one projection display device may be provided. In this embodiment, the projection display device is provided separately from the headlamp. However, the projection display device may function as a headlamp.

  The driver photographing camera 21a photographs the driver's face of the host vehicle 100 in real time. The driver photographing camera 21 a is connected to the arithmetic device 24. Image data photographed by the driver photographing camera 21 a is input to the arithmetic device 24.

  The rain sensor 21b detects the amount of rainfall by detecting the presence of water droplets on the windshield of the host vehicle 100. The rainfall sensor 21b is connected to the arithmetic device 24. The detection value of the rainfall sensor 21b is input to the arithmetic device 24.

  The light receiving sensor 21 c detects the brightness around the host vehicle 100. The light receiving sensor 21 c is connected to the arithmetic device 24. The detection value of the light receiving sensor 21c is input to the arithmetic device 24.

The storage device 22 is configured by a memory device such as a ROM or a RAM. The storage device 22 stores attention target maximum number data 22b, time interval maximum number data 22c, projection start time data 22d, projection pattern data 22e, and the like. Each data stored in the storage device 22 is read by the arithmetic device 24 as necessary.
The attention target maximum number data 22b is data indicating the maximum number of attention objects with which the driver can accurately recognize each attention object when the host vehicle 100 passes through a plurality of attention objects. In the present embodiment, the value indicated by the attention target maximum number data 22b is two.
The maximum time interval number data 22c indicates that the driver accurately identifies each caution target when a section in which the vehicle 100 passes at a time interval shorter than the determination time (detailed later) (that is, a section between caution targets) continues. This is data indicating the maximum number of continuous numbers that can be recognized. In this embodiment, the time interval maximum number data 22c is set to a value obtained by subtracting 1 from the maximum number data (that is, one).
The projection start time data 22d is data indicating the timing of projecting an image for instructing deceleration in front of the host vehicle 100. As will be described in detail later, the deceleration instruction device 10 needs to project an image for instructing deceleration when the number of consecutive sections between attention objects passing at a time interval shorter than the determination time is greater than the maximum number of time intervals. judge. When it is necessary to project an image, the deceleration instruction device 10 uses the attention target group that the host vehicle first reaches in the attention target group included in the continuous section (the section that passes at a short time interval) (that is, When the arrival time until it reaches the earliest target object) is shorter than the projection start time, an image for instructing deceleration is projected onto the road surface ahead of the host vehicle. In the present embodiment, the projection start time indicated by the projection start time data 22d is 2.9 seconds.
The projection pattern data 22e is data including a plurality of image data describing an image projected in front of the host vehicle 100. Each image data included in the projection pattern data 22e is data describing an image for displaying a message indicating a speed such as “20 km / h”, “30 km / h”, “40 km / h”. In front of the host vehicle 100, an image described by the image data selected by the arithmetic unit 24 among the image data included in the projection pattern data 22e is projected.

The arithmetic device 24 is a microcomputer provided with a CPU and the like. The arithmetic device 24 also includes a storage area including a ROM, a RAM, and the like. As shown in FIG. 2, the arithmetic device 24 includes a driving time counting unit 41, a determination time determining unit 42, an intersection specifying unit 25, a pedestrian specifying unit 26, a pedestrian position calculating unit 27, a pedestrian position storage unit 28, and a walking. Person movement speed calculation unit 29, accompanying body identification unit 30, approaching pedestrian identification unit 31, other vehicle identification unit 32, other vehicle position calculation unit 33, other vehicle position storage unit 34, other vehicle movement speed calculation unit 35, parked vehicle It functions as a specification unit 36, an obstacle specification unit 37, an arrival time calculation unit 38, a time interval prediction unit 39, and a projection control unit 40. The pedestrian position storage unit 28 and the other vehicle position storage unit 34 are configured by a storage area of the calculation device 24. Other components (reference numbers 25 to 27, 29 to 33, and 35 to 42) are realized by the calculation function of the calculation device 24. The operation of the components 25 to 42 of the arithmetic device 24 will be described later. As will be understood from the following description, in the deceleration instruction device 10 of the present embodiment, the car navigation system 14, the cameras 12a and 12b, the speed sensor 16, the intersection specifying unit 25, the pedestrian specifying unit 26, and the pedestrian position calculating unit. 27, pedestrian position storage unit 28, pedestrian movement speed calculation unit 29, accompanying body identification unit 30, approach pedestrian identification unit 31, other vehicle identification unit 32, other vehicle position calculation unit 33, other vehicle position storage unit 34, The other vehicle moving speed calculation unit 35, the parked vehicle specifying unit 36, and the obstacle specifying unit 37 as a whole are the attention object information output means of the claims (ie, the position of the attention object in front of the host vehicle 100 and the relative movement speed). Function to identify and output the data.
The computing device 24 identifies the situation ahead of the host vehicle 100 based on the map data input from the car navigation system 14, the image data input from the cameras 12a and 12b, and the like. Then, an image is projected on the projection display device 20 according to the situation ahead of the identified host vehicle 100.

Next, processing executed by the deceleration instruction device 10 while the host vehicle 100 is traveling will be described.
While the host vehicle 100 is traveling, the car navigation system 14 receives a GPS signal at a constant cycle, and calculates the position and traveling direction of the host vehicle 100 each time the GPS signal is received. The car navigation 14 outputs the position data and travel direction data of the host vehicle 100 and map data around the host vehicle 100 to the arithmetic device 24 at a constant cycle.
Further, the camera 12 a captures an image in front of the host vehicle 100 at a constant cycle while the host vehicle 100 is traveling, and outputs the captured image data to the arithmetic device 24. Similarly, the camera 12b also captures an image in front of the host vehicle 100 at a constant cycle while the host vehicle 100 is traveling, and outputs the captured image data to the arithmetic device 24.
Further, the speed sensor 16 detects the traveling speed of the host vehicle 100 at a constant period, and outputs the detected traveling speed data to the arithmetic device 24.
Further, the steering angle sensor 18 detects the steering angle of the host vehicle 100 at a constant cycle, and outputs the detected steering angle data to the arithmetic device 24.
Further, the driver photographing camera 21 a captures images of the driver's face at regular intervals while the host vehicle 100 is traveling, and outputs the captured image data to the arithmetic device 24.
Further, the rainfall sensor 21 b detects the amount of rainfall at a constant cycle while the host vehicle 100 is traveling, and outputs the detected value to the arithmetic device 24.
Further, the light receiving sensor 21 c detects the brightness around the host vehicle 100 at a constant cycle while the host vehicle 100 is traveling, and outputs the detected value to the arithmetic device 24.
Therefore, while the host vehicle 100 is traveling, the position data of the host vehicle 100, the traveling direction data of the host vehicle 100, the map data around the host vehicle 100, the image data captured by the camera 12a, and the camera 12b. The image data, traveling speed data, steering angle data, driver face image data, determination value of the rain sensor 21b, and detection value of the light receiving sensor 21c are input to the arithmetic device 24 as needed. Is done.
In addition, the driving time counting unit 41 of the arithmetic device 24 counts the time since the driving of the host vehicle 100 is started.

  FIG. 3 is a flowchart showing processing executed by the arithmetic device 24 while the host vehicle 100 is traveling.

  In step S2, the arithmetic unit 24 acquires image data output by the cameras 12a and 12b.

  In step S <b> 4, the arithmetic device 24 acquires position data of the host vehicle 100 output from the car navigation system 14, travel direction data of the host vehicle 100, and map data around the position of the host vehicle 100.

  In step S <b> 6, the computing device 24 identifies a cautionary object that exists in front of the host vehicle 100 and calculates the position of the identified cautionary object. The computing device 24 selects four types of caution objects: an intersection, a pedestrian who may enter the planned travel range of the host vehicle (hereinafter referred to as an approaching pedestrian), a parked vehicle, and an obstacle on the road surface. Identify. The processing for specifying each attention object in step S6 and calculating the position will be described below for each attention object.

(Process to calculate the position by specifying the intersection)
In the process of calculating the position by specifying the intersection, the intersection specifying unit 25 uses the position data of the host vehicle 100 acquired in step S4, the traveling direction data of the host vehicle 100, and the map data around the host vehicle 100. The intersection which exists ahead of the own vehicle 100 (running direction) is specified. Then, the relative position of the identified intersection with respect to the own vehicle 100 (position coordinates of the intersection with the own vehicle 100 as the origin) is calculated from the position data of the own vehicle 100 and the map data around the own vehicle 100. The intersection identifying unit 25 outputs the calculated position of the intersection to the arrival time calculating unit 38.

(Process to calculate the position by specifying the approaching pedestrian)
FIG. 4 is a flowchart showing a process of calculating the position by specifying an approaching pedestrian who may enter the scheduled travel range of the host vehicle 100.

  In step S50, the pedestrian specifying unit 26 uses the image data acquired in step S2 (the image data output by the camera 12a and the image data output by the camera 12b), and the pedestrians reflected in those images (that is, A pedestrian in front of the host vehicle 100) is identified. The identification of the pedestrian is performed by recognizing the shape of the pedestrian on each image data. Since the technique for specifying the pedestrian from the image data is a conventionally known technique, a detailed description thereof will be omitted. When a plurality of pedestrians are shown in the image data, the pedestrian specifying unit 26 specifies each pedestrian. In this process, the shape of the person riding the bicycle is also specified as a pedestrian. In the following processing, a person riding a bicycle is also described as a pedestrian.

In step S52, the pedestrian position calculation unit 27 uses the image data acquired in step S2 (the image data output by the camera 12a and the image data output by the camera 12b), and the pedestrian's own identity specified in step S50. A relative position with respect to the vehicle 100 is calculated.
For example, as shown in FIG. 5, consider a case where a pedestrian 102 is present in front of the cameras 12a and 12b (that is, in front of the host vehicle 100). In this case, the camera 12a captures an image as shown in FIG. The camera 12b captures an image as shown in FIG. 6 and 7, reference numeral 104 indicates a roadway on which the host vehicle 100 is traveling, and reference numeral 106 indicates a sidewalk beside the roadway 104. In step S52, the pedestrian position calculator 27 calculates the horizontal center position 108a of the image data of the camera 12a shown in FIG. 6 and the pedestrian 102 (more specifically, the center position of the pixel indicating the pedestrian 102). The number of pixels A1 between them (that is, the distance in the horizontal direction on the center position 108a and the image of the pedestrian 102) is calculated. Then, an angle B1 in FIG. 5 (an angle between a straight line C1 connecting the camera 12a and the pedestrian 102 and a straight line C2 indicating the front direction of the camera 12a) is calculated from the calculated pixel number A1. Similarly, the pedestrian position calculation unit 27 calculates the number of pixels A2 between the horizontal center position 108b of the image data of the camera 12b shown in FIG. 7 and the pedestrian 102. Then, an angle B2 in FIG. 5 (an angle between a straight line C3 connecting the camera 12b and the pedestrian 102 and a straight line C4 indicating the front direction of the camera 12b) is calculated from the calculated pixel number A2. The pedestrian position calculating unit 27 calculates the relative position of the pedestrian 102 relative to the host vehicle 100 (X1 in FIG. 5) from the calculated angle B1 and angle B2 and the distance H1 between the camera 12a and the camera 12b (see FIG. 5). Y1) is calculated (note that the point P1 in FIG. 5 indicates the midpoint between the camera 12a and the camera 12b). When a plurality of pedestrians are specified in step S50, the pedestrian position calculation unit 27 calculates the relative position of each specified pedestrian.

  The relative position of the pedestrian calculated by the pedestrian position calculation unit 27 is stored in the pedestrian position storage unit 28 together with the time when the relative position is calculated. The process shown in FIG. 3 is repeatedly executed while the host vehicle 100 is traveling. Therefore, the pedestrian position calculation unit 27 repeatedly calculates the relative position of the pedestrian. Each time the pedestrian position calculation unit 27 calculates the relative position of the pedestrian, the pedestrian position storage unit 28 stores the calculated relative position of the pedestrian. Therefore, the relative position of the pedestrian previously calculated by the pedestrian position calculation unit 27 is stored in the pedestrian position storage unit 28 in time series.

  In step S54 of FIG. 4, the pedestrian movement speed calculation unit 29 calculates the current relative position of the pedestrian calculated by the pedestrian position calculation unit 27 in step S52 and the past stored in the pedestrian position storage unit 28. From the relative position of the pedestrian, a relative movement speed vector (a vector indicating a relative movement speed and a relative movement direction with respect to the own vehicle 100) of the pedestrian is calculated. When a plurality of pedestrians are specified in step S50, the pedestrian movement speed calculation unit 29 calculates a relative movement speed vector of each specified pedestrian.

In step S56, the accompanying body specifying unit 30 specifies a pedestrian who is the accompanying body.
For example, when the first pedestrian and the second pedestrian are specified, the accompanying body specifying unit 30 first calculates the first pedestrian relative position and the second pedestrian relative position from the first pedestrian relative position. It is determined whether the distance interval between the pedestrian and the second pedestrian is equal to or smaller than a predetermined interval. When the distance interval is equal to or smaller than the predetermined distance interval, the accompanying body specifying unit 30 calculates the pedestrian calculated by the difference between the relative movement speed vector of the first pedestrian and the relative movement speed vector of the second pedestrian. The absolute value of the relative movement speed vector is calculated. When the calculated absolute value is equal to or less than a certain value, it is considered that the first pedestrian and the second pedestrian are moving together. The second pedestrian is identified as an accompanying body. The accompanying body specifying unit 30 performs the above process for each pedestrian specified in step S50. A plurality of pedestrians identified as being accompanied by the accompanying body specifying unit 30 are calculated as one pedestrian in the following processing.

In step S58, the approaching pedestrian identification unit 31 identifies an approaching pedestrian who may enter the planned travel range of the host vehicle 100 from the pedestrians identified in step S50. Whether or not there is a possibility that the pedestrian may enter the scheduled travel range of the vehicle 100 is based on the position of the pedestrian calculated in step S52 and the relative movement speed vector of the pedestrian calculated in step S54. Determined. That is, the approaching pedestrian specifying unit 31 calculates whether or not the host vehicle 100 exists within the angle range D1 in the relative movement speed vector direction from the position of the pedestrian. When the host vehicle 100 exists in the angle range D1, it is determined that the pedestrian may enter the scheduled travel range of the host vehicle 100.
For example, consider a case where pedestrians 110 to 114 exist as shown in FIG. In addition, the arrows 110a-114a of FIG. 8 have shown the relative movement speed vector of the pedestrians 110-114. As shown in FIG. 8, the pedestrian 112 has a straight line extending the relative moving speed vector 112 a intersecting the host vehicle 100. Therefore, assuming that the pedestrian 112 has moved as indicated by the relative movement speed vector 112a, the pedestrian 112 and the host vehicle 100 are considered to be very close. In this case, the approaching pedestrian specifying unit 31 determines that there is a possibility that the pedestrian 112 may enter the scheduled travel range of the host vehicle 100. In addition, the pedestrian 110 does not intersect the vehicle 100 with a straight line obtained by extending the relative movement speed vector 110a. However, the host vehicle 100 exists within the angle range D1 in the direction of the relative movement speed vector 110a. Therefore, when the relative movement speed vector 110a of the pedestrian 110 changes as indicated by the arrow 110b, the pedestrian 110 and the host vehicle 100 are considered to be very close. Therefore, the approaching pedestrian specifying unit 31 determines that there is a possibility that the pedestrian 110 may enter the scheduled travel range of the host vehicle 100. On the other hand, the pedestrian 114 does not have the host vehicle 100 within the angle range D1 in the direction of the relative movement speed vector 114a. Therefore, the approaching pedestrian specifying unit 31 determines that there is no possibility that the pedestrian 114 enters the scheduled travel range of the host vehicle 100.
When the approaching pedestrian identification unit 31 identifies an approaching pedestrian who may enter the planned travel range of the host vehicle 100, the approaching pedestrian identification unit 31 outputs the identified position and relative movement vector of the approaching pedestrian to the arrival time calculation unit 38.

(Process to calculate the position by specifying the parked vehicle)
FIG. 9 is a flowchart illustrating a process of calculating a position by specifying a parked vehicle.

  In step S60, the other vehicle identification unit 32 uses other images (that is, the image data output from the camera 12a and the image data output from the camera 12b) acquired in step S2 to be reflected in those images (that is, the image data output from the camera 12b). Vehicle in front of the host vehicle 100) is identified. The identification of the other vehicle is performed by recognizing the shape of the vehicle on each image data as in step S50 of FIG.

  In step S62, the other vehicle position calculation unit 33 determines the own vehicle of the other vehicle specified in step S60 based on the image data acquired in step S2 (image data output by the camera 12a and image data output by the camera 12b). A relative position with respect to the vehicle 100 is calculated. The calculation of the relative position of the other vehicle is performed in the same manner as the calculation of the relative position of the pedestrian described in step S52 of FIG.

  The relative position of the other vehicle calculated by the other vehicle position calculation unit 33 is stored in the other vehicle position storage unit 34 together with the time when the relative position is calculated. The process shown in FIG. 3 is repeatedly executed while the host vehicle 100 is traveling. Therefore, the other vehicle position calculation unit 33 repeatedly calculates the relative position of the other vehicle. Each time the other vehicle position calculation unit 33 calculates the relative position of the other vehicle, the other vehicle position storage unit 34 stores the calculated relative position of the other vehicle. Therefore, the relative position of the other vehicle previously calculated by the other vehicle position calculation unit 33 is stored in the other vehicle position storage unit 34 in time series.

  In step S64, the other vehicle movement speed calculation unit 35 calculates the relative position of the other vehicle calculated by the other vehicle position calculation unit 33, the past relative position of the other vehicle stored in the other vehicle position storage unit 34, and From the traveling speed of the host vehicle 100 detected by the speed sensor 16, an absolute moving speed vector (moving speed vector based on a stationary object) of the identified other vehicle is calculated. When a plurality of other vehicles are specified in step S60, the other vehicle moving speed calculation unit 35 calculates an absolute moving speed vector of each specified other vehicle.

  In step S66, the parked vehicle specifying unit 36 specifies a parked vehicle from the other vehicles specified in step S60. The parked vehicle specifying unit 36 specifies other vehicles whose absolute value of the absolute moving speed vector calculated in step S64 is equal to or less than a certain value (that is, a speed at which the moving speed is considered to be zero) as a parked vehicle. . When the parked vehicle identifying unit 36 identifies the parked vehicle, the parked vehicle identifying unit 36 outputs the position of the parked vehicle to the arrival time calculating unit 38.

(Process to calculate obstacles by identifying obstacles)
The process of specifying the obstacle and calculating the position is performed in the same manner as steps S50 and S52 in FIG.
That is, first, the obstacle identifying unit 37 determines the obstacle on the road surface ahead of the host vehicle 100 from the image data acquired in step S2 (image data output by the camera 12a and image data output by the camera 12b). Identify existence. The identification of the obstacle is performed by recognizing the shape of the obstacle on the road surface on each image data as in step S50 of FIG.
Next, the obstacle identifying unit 37 calculates the relative position of the identified obstacle with respect to the host vehicle 100 based on the image data acquired in step S2. The calculation of the relative position of the obstacle is performed in the same manner as the calculation of the relative position of the pedestrian described in step S52 of FIG.

  By executing each process described above in step S6, the relative positions of the four types of attention objects of the intersection, the approaching pedestrian, the parked vehicle, and the obstacle on the road surface are calculated.

  In step S <b> 8 of FIG. 3, the arrival time calculation unit 38 reads the attention target maximum number data 22 b from the storage device 22. Then, it is determined whether or not the number of attention objects specified in step S6 is greater than the maximum number of attention objects (that is, two) indicated by the attention object maximum number data 22b. When the number of specified attention objects is three or more (that is, when YES in step S8), step S9 is executed by the determination time determination unit 42. If the specified number of attention objects is two or less (that is, if NO in step S8), the arithmetic unit 24 stops projecting an image by the projection display device 20 in step S22. (When the image is not projected before the execution of step S22, the state where the image is not projected is maintained). And the process from step S2 is performed again.

In step S9, the determination time determination unit 42 determines the determination time. The determination time is a time interval (a time interval through which each caution object passes) that is considered to be accurately recognized by the driver when the host vehicle 100 passes through a plurality of caution objects. The determination time depends on the situation during driving (the situation of the driver, the number of attention objects in front of the host vehicle 100, the situation around the host vehicle, etc.). Therefore, the determination time determination unit 42 calculates the determination time based on the situation at the time of traveling.
That is, the determination time determination unit 42 reads out the operation time counted by the operation time counting unit 41.
In addition, the determination time determination unit 42 calculates the number of times the driver blinks from image data within a predetermined time taken by the driver photographing camera 21a. A driver's blink is detected by recognizing an image of the driver's face. The determination time determination unit 42 calculates a sleepiness index (a value indicating that the driver feels sleepier as the value is higher) from the number of times the driver blinks.
In addition, the determination time determination unit 42 calculates a time ratio (hereinafter referred to as a side index) that the driver watched from the image data within a predetermined time taken by the driver photographing camera 21a. Driver side effects are detected by recognizing the driver's viewpoint from the image.
In addition, the determination time determination unit 42 reads the rainfall amount detected by the rainfall sensor 21b.
In addition, the determination time determination unit 42 calculates a value indicating darkness (calculated as a higher value as it is darker) from the brightness detected by the light receiving sensor 21c.
Then, the determination time is determined based on the driving time, the sleepiness index, the side index, the amount of rainfall, the darkness, and the number of attention objects specified in step S6. The ability of a human to recognize an attention object decreases as these values (ie, driving time, sleepiness index, side effect index, rainfall, darkness, and number of attention objects) increase. Therefore, the determination time determination unit determines the determination time longer as these values are larger.

In step S10, the arrival time calculation unit 38 calculates the arrival time for the host vehicle 100 to reach each attention target.
When the attention object is an approaching pedestrian, the arrival time calculation unit 38 calculates the distance from the vehicle 100 to the approaching pedestrian based on the relative position of the approaching pedestrian. Then, the arrival time to the approaching pedestrian is calculated by dividing the calculated distance by the relative movement speed of the approaching pedestrian. For example, when the approaching pedestrian 120 exists as shown in FIG. 10, the distance L1 between the own vehicle 100 and the approaching pedestrian 120 is determined by the relative movement speed of the approaching pedestrian 120 (the absolute value of the relative movement vector). Divide and calculate the arrival time to the approaching pedestrian 120. Also for the pedestrian 122, the distance L2 is divided by the relative movement speed of the pedestrian 122, and the arrival time to the approaching pedestrian 122 is calculated.
When the attention object is a stationary object (that is, an intersection, a parked vehicle, and an obstacle), the arrival time calculation unit 38 is based on the steering angle data input from the steering angle sensor 18 and the predicted course of the host vehicle 100. Is calculated. Next, the arrival time calculation unit 38 calculates the distance from the host vehicle 100 to the attention object in the direction along the prediction path based on the calculated predicted path and the relative position of the attention object. That is, a perpendicular line is drawn with respect to the predicted course from the position of the attention object, and the intersection of the perpendicular and the predicted course is calculated. And the distance (distance along a predicted course) from the own vehicle 100 to the calculated intersection is calculated. For example, as shown in FIG. 10, when the predicted course 130 of the host vehicle 100 is a straight line, the distance L3 is calculated as the distance to the intersection 124. Also, as shown in FIG. 11, when the predicted course 130 of the host vehicle 100 is curved, the distance L4 is calculated as the distance to the intersection 124. Next, the arrival time calculation unit 38 divides the distance from the host vehicle 100 to the attention object by the traveling speed of the host vehicle 100 detected by the speed sensor 16. Thus, the arrival time until the host vehicle 100 reaches the attention object is calculated (if the attention object is a stationary object, the traveling speed of the host vehicle 100 corresponds to the relative movement speed of the attention object, and the speed sensor 16 is a means for specifying the relative speed of the attention object).
The arrival time calculation unit 38 performs the above process on each attention object, and calculates the arrival time until the host vehicle 100 reaches each attention object.

  In step S12, the time interval prediction unit 39 predicts the time interval for the host vehicle 100 to pass each caution object based on the arrival time to each caution object calculated in step S10. For example, in the case shown in FIG. 10, the arrival time to the pedestrian 120 is t1, the arrival time to the pedestrian 122 is t2, the arrival time to the intersection 124 is t3, and t1 <t2 <t3 In some cases, t1 is subtracted from t2 to calculate (predict) the time interval from passing through the pedestrian 120 to passing through the pedestrian 122, and subtracting t2 from t3 to calculate the intersection 124 from the pedestrian 122. The time interval until passing through is calculated (predicted).

  In step S <b> 14, the projection control unit 40 determines whether each time interval calculated in step S <b> 12 is shorter than the determination time determined by the determination time determination unit 42. Then, it is determined whether or not the number of consecutive sections between attention objects passing at a time interval shorter than the determination time (hereinafter simply referred to as a short time interval) is greater than the maximum number of time intervals (ie, one). For example, consider a case where pedestrians 141 to 144 exist as shown in FIG. In this example, the time interval dt1 between the pedestrian 141 and the pedestrian 142 is short, the time interval dt2 of the section between the pedestrian 142 and the pedestrian 143 is short, and the time interval between the pedestrian 142 and the pedestrian 143 When t3 is long, the continuous number of sections that pass at short time intervals is two. Hereinafter, each attention object included in a continuous section that passes at a short time interval is referred to as a attention object group that passes at a short time interval. In the above example, the pedestrians 141, 142, and 143 are included in the attention target group that passes at short time intervals. In addition, when the time interval dt1 is short, the time interval dt2 is long, and the time interval dt3 is short, the number of consecutive sections that pass through the short time interval is 1 (that is, not continuous). When the continuous number is 2 or more (that is, when YES in step S14), the projection control unit 40 executes step S16. When the continuous number is 1 or less (that is, when NO in step S14), the arithmetic unit 24 executes the process from step S2 again after executing step S22 described above.

  In step S <b> 16, the projection control unit 40 determines the traveling speed of the host vehicle 100 so that the time interval passing through each section between the attention objects included in the attention object group that passes at a short time interval is equal to or greater than the determination time. Target travel speed) is calculated. For example, in the example of FIG. 12, when all the time intervals dt1 to dt3 are equal to or less than the determination time, the target travel speed of the host vehicle 100 is calculated so that all the time intervals dt1 to dt3 are equal to or greater than the determination time. To do. In this case, the target travel speed of the host vehicle 100 is calculated based on the positions and relative movement vectors of the pedestrians 141 to 144, the determination time, and the current travel speed of the host vehicle 100.

In step S <b> 18, the projection control unit 40 calculates the arrival time until the host vehicle reaches the attention object that arrives first (that is, the attention object that arrives first) among the attention object group that passes at short time intervals. To do. Then, it is determined whether or not the calculated arrival time is shorter than the projection start time (that is, 2.9 seconds) indicated by the projection start time data 22d. When the calculated arrival time is longer than the projection start time (that is, in the case of NO in step S18), the arithmetic unit 24 executes the processing from step S2 again. When the calculated arrival time is shorter than the projection start time (that is, in the case of YES at step S18), the projection control unit 40 executes step S20.
For example, as shown in FIG. 13, there are pedestrians 161 to 167, the pedestrians 162 to 164 are the first attention object group 171 that passes at a short time interval, and the pedestrians 165 to 167 pass at a short time interval. (Ie, the time interval passing through the section between the pedestrians 161-162 and the time interval passing through the section between the pedestrians 164-165 are equal to or greater than the determination time) (Each section has a time interval less than the judgment time). In this case, when the arrival time to reach the attention object (that is, the pedestrian 162) that reaches the host vehicle earliest among the attention objects included in the attention object group 171 is shorter than the projection start time, in step S18. It determines with YES.

  In step S20, the projection control unit 40 is closest to the target travel speed calculated in step S16 among the image data included in the projection pattern data 22e stored in the storage device 22, and is lower than the target travel speed. An image displaying the target traveling speed is read out. Then, the read image data is transmitted to the projection display device 20. Thereby, the projection display device 20 projects the image indicated by the received image data on the road surface ahead of the host vehicle 100. For example, when the target travel speed V2 calculated in step S16 is 35 km / h, the projection control unit 40 reads out image data indicating “30 km / h” from the storage device 22 and stores it in the projection display device 20. Send. Therefore, the projection display device 20 displays an image displaying “30 km / h” on the road surface ahead of the host vehicle 100. Therefore, the driver of the own vehicle 100 can reduce the traveling speed of the own vehicle 100 to a target traveling speed or less in accordance with the instruction of the image displayed on the road surface. When the traveling speed of the host vehicle 100 is reduced to be equal to or lower than the target traveling speed, it is possible to travel at a time interval equal to or longer than the determination time in the section between all the attention objects. As a result, the driver can recognize and travel reliably without overlooking each attention object.

The arithmetic unit 24 repeatedly executes the process of FIG. 3 described above. Therefore, the target object in front of the host vehicle 100 is always specified while the host vehicle 100 is traveling. And when the specified attention object satisfies the following conditions, the image which instruct | indicates deceleration on the road surface ahead of the own vehicle 100 is projected.
(1) The number of attention objects is greater than the maximum number of attention objects (that is, 2) (that is, 3 or more).
(2) The number of consecutive sections passing at a time interval shorter than the determination time is greater than the maximum number of time intervals (ie, 1) (ie, 2 or more).
(3) Among the attention objects included in the attention object group that passes at a short time interval, the arrival time until the host vehicle reaches the attention object that reaches the earliest is calculated from the projection start time (that is, 2.9 seconds). short.

  Thus, the deceleration instruction apparatus according to the present embodiment may prevent the driver from accurately recognizing each caution target because the situation ahead of the host vehicle 100 satisfies the above conditions (1) to (3). When there is, an image for instructing deceleration is projected. Therefore, the driver can decelerate the host vehicle 100 to a safe speed. In other words, each attention object can be passed at a speed at which each attention object can be accurately recognized. In addition, since a plurality of information is not transmitted to the driver but the target travel speed of the host vehicle 100 is transmitted to the driver, the driver can reduce the travel speed of the host vehicle 100 without hesitation. . In addition, since an image is projected on the road surface in front of the host vehicle 100, the driver can confirm the deceleration (that is, the target traveling speed) without moving the viewpoint or the focus.

  Moreover, in the Example mentioned above, the approaching pedestrian specific | specification part 31 specifies the approaching pedestrian who may enter into the planned driving | running | working range of the own vehicle 100 from the pedestrian specified by the pedestrian specific part 26. Only the specified approaching pedestrian is output as a target of attention. Therefore, it is possible to prevent an excessively large number of pedestrians from becoming an object of attention and projecting an image instructing deceleration until unnecessary.

  Moreover, in the Example mentioned above, the accompanying body specific | specification part 30 specifies the pedestrian who is an accompanying body. And approaching pedestrian specific part 31 processes a plurality of pedestrians who are accompanying bodies as one pedestrian. Therefore, it is possible to prevent a time interval (that is, a very short time interval) passing through a section between pedestrians who are accompanying persons from being calculated and projecting an image instructing deceleration.

  In the above-described embodiment, the maximum number of attention objects and the maximum number of time intervals are set. Therefore, it is prevented that an image instructing deceleration is projected until the driver can surely recognize each attention object.

In the above-described embodiment, the determination time is changed based on the driving condition (driving time, sleepiness index, side index, rainfall amount, darkness, and the number of attention objects). However, the determination time may be a fixed value. Moreover, you may change judgment time according to a driver | operator's ability (a driver | operator's age, sex, etc.). The determination time may be set by the driver himself or may be set in advance by the manufacturer.
In the above-described embodiment, the maximum number of attention objects is two. However, the maximum number of attention objects may be changed according to the ability of the driver, the situation at the time of driving, and the like. The maximum number of attention objects may be set by the driver himself or may be set in advance by the manufacturer.
In the above-described embodiment, the maximum number of time intervals is 1. However, the maximum number of time intervals may be changed according to the ability of the driver, the situation at the time of traveling, and the like. The maximum number of time intervals may be set by the driver himself or may be set in advance by the manufacturer.
In the above-described embodiment, the projection start time is 2.9 seconds. However, the projection start time may be changed according to the ability of the driver, the situation at the time of traveling, and the like. The projection start distance may be set by the driver himself or may be set in advance by the manufacturer. Further, instead of determining the timing to start projection based on the projection start time, the projection may be started when the distance to the attention object that reaches first becomes a certain value or less.

  Moreover, in the Example mentioned above, the position of each attention object (a pedestrian, a parked vehicle, and an obstruction) was calculated from the difference of the image of the camera 12a, and the image of the camera 12b. However, the deceleration instruction device 10 may include a device that measures the position of the attention object, such as a laser radar or a millimeter wave radar. Even with such a configuration, the position of the attention object can be measured. In this case, the number of cameras (that is, a device that acquires an image in front of the host vehicle 100) may be one. Planar projection stereo method (photographs the front with two cameras, calculates the difference between the pixel value of the image data of one camera and the corresponding pixel value of the image data of the other camera, and identifies the object) Method). Alternatively, a moving stereo technique (a technique for continuously capturing images with a single camera and identifying a three-dimensional object from the continuously captured images) may be used. Also in this case, one camera can be used.

In the above-described embodiment, the image indicating the target traveling speed is displayed on the road surface in front of the host vehicle 100, but another image may be displayed.
For example, a message such as “slow speed” or “slow down” may be displayed.
Further, as in the example illustrated in FIG. 14, a striped pattern across the traveling direction of the host vehicle 100 may be projected on the road surface in front of the host vehicle 100. At this time, the image is changed so that the striped pattern moves to the near side at the substantially same speed as the traveling speed of the host vehicle 100 (that is, moves in the direction indicated by the arrow 150 in FIG. 14). The projected stripe pattern looks like road surface unevenness when viewed from the driver. Therefore, the driver can be prompted to decelerate the host vehicle 100.
In the example shown in FIG. 14, the image may be changed so that the striped pattern moves to the near side at a speed faster than the traveling speed of the host vehicle 100. According to such a configuration, the driver feels that he is traveling at a speed faster than the actual traveling speed of the host vehicle 100. Therefore, the driver can be prompted to decelerate the host vehicle 100.
Further, for example, as in the example shown in FIG. 15, only the front central portion (the central portion with respect to the vehicle width) of the host vehicle 100 is irradiated, and the side portion in front of the own vehicle 100 (the side portion with respect to the vehicle width) is not irradiated. An image may be projected. According to such a configuration, the driver feels that the width of the road on which the host vehicle 100 travels is narrow. Therefore, the driver can be prompted to decelerate the host vehicle 100.

  Further, the deceleration instruction device 10 of the above-described embodiment may be operated either during the day or at night. However, since it is difficult for the driver to recognize the attention object at night, it is more effective to operate at night.

  In addition, although the deceleration instruction | indication apparatus 10 mentioned above can acquire a high effect, even if it uses independently, it is used in combination with the technique which irradiates a spot light toward an attention object like the prior art, Recognition can be improved. For example, a deceleration instruction image is projected when the number of consecutive intervals between attention objects whose time intervals are shorter than the maximum number of time intervals, and spot light is irradiated to each attention object when the number of consecutive times is less than the maximum number of time intervals. You may do it. According to such a configuration, the driver can travel more safely without overlooking each attention target.

Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above.
The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology illustrated in the present specification or the drawings achieves a plurality of objects at the same time, and has technical utility by achieving one of the objects.

The figure which shows schematic structure of the deceleration instruction | indication apparatus 10 mounted in the own vehicle 100. FIG. FIG. 2 is a block diagram showing a configuration of a deceleration instruction device 10. The flowchart which shows the process which the arithmetic unit 24 performs. The flowchart which shows the process which specifies an approaching pedestrian. Explanatory drawing explaining the position calculation method of a pedestrian. The figure which illustrates the picture photoed with camera 12a. The figure which illustrates the picture photoed with camera 12b. The figure explaining the identification method of an approaching pedestrian. The flowchart which shows the process which specifies a parked vehicle. Explanatory drawing explaining the arrival time to attention object. Explanatory drawing explaining the arrival time to attention object. Explanatory drawing explaining the time interval which passes each attention object. Explanatory drawing explaining the projection start timing. The figure which shows the image which the deceleration instruction | indication apparatus of a modification projects on the road surface ahead of the own vehicle. The figure which shows the image which the deceleration instruction | indication apparatus of a modification projects on the road surface ahead of the own vehicle.

Explanation of symbols

10: Deceleration instruction device 12a: Camera 12b: Camera 14: Car navigation system 14a: Map data storage unit 14b: Own vehicle position calculation unit 14c: GPS antenna 16: Speed sensor 18: Steering angle sensor 20a: Projection type display device 20b: Projection type display device 22: storage device 22b: attention object maximum number data 22c: time interval maximum number data 22d: projection start time data 22e: projection pattern data 24: arithmetic device 25: intersection specifying unit 26: pedestrian specifying unit 27: Pedestrian position calculation unit 28: Pedestrian position storage unit 29: Pedestrian movement speed calculation unit 30: Accompanying body specifying unit 31: Entering pedestrian specifying unit 32: Other vehicle specifying unit 33: Other vehicle position calculating unit 34: Other vehicle Position storage unit 35: other vehicle moving speed calculation unit 36: parked vehicle identification unit 37: obstacle identification unit 38: arrival time calculation unit 39: time Interval prediction unit 40: the projection control unit 100: vehicle

Claims (6)

A device for instructing the driver to decelerate according to the situation ahead of the traveling vehicle,
A determination time determining means for determining a determination time;
Projecting means for projecting an image onto the road surface ahead of the host vehicle;
Attention object information output means for specifying and outputting the position of the attention object in front of the host vehicle and the relative movement speed;
When the position and relative movement speed of a plurality of attention objects are output by the attention object information output means, the own vehicle reaches each attention object based on the output position and relative movement speed of each attention object. An arrival time calculating means for calculating the required arrival time;
A time interval prediction means for predicting a time interval in which the host vehicle passes each attention object from each arrival time calculated by the arrival time calculation means;
Projection that projects an image instructing deceleration on the road surface ahead of the host vehicle when at least one of the time intervals predicted by the time interval prediction unit is shorter than the determination time determined by the determination time determination unit Control means,
A deceleration instructing device comprising: Attention target information output means,
Image acquisition means for acquiring an image ahead of the host vehicle;
Pedestrian position specifying means for specifying the position of the pedestrian from the image acquired by the image acquisition means;
Pedestrian position storage means for storing the position of the pedestrian specified by the pedestrian position specifying means;
Pedestrian relative movement speed specification that specifies the relative movement speed of the pedestrian from the past position of the pedestrian stored by the pedestrian position storage means and the current position of the pedestrian specified by the pedestrian position specification means Means,
Walking that may enter the planned travel range of the vehicle from the current position of the pedestrian specified by the pedestrian position specifying means and the relative movement speed of the pedestrian specified by the pedestrian relative movement speed specifying means Pedestrian information output means for specifying and outputting the position and relative movement speed of the person,
The deceleration instruction device according to claim 1, further comprising: Attention target information output means,
Traveling speed detecting means for detecting the traveling speed of the host vehicle;
Map data storage means for storing map data;
GPS signal receiving means for receiving GPS signals;
Own vehicle position calculating means for calculating the position of the own vehicle from the GPS signal received by the GPS signal receiving means;
An intersection position specifying means for specifying the position of an intersection existing ahead of the own vehicle from the map data stored by the map data storage means and the position of the own vehicle calculated by the own vehicle position calculating means;
Intersection information output means for outputting the position of the intersection specified by the intersection position specifying means and the traveling speed detected by the traveling speed detecting means;
The deceleration instruction device according to claim 1 or 2, further comprising: Attention target information output means,
Traveling speed detecting means for detecting the traveling speed of the host vehicle;
Image acquisition means for acquiring an image ahead of the host vehicle;
Other vehicle position specifying means for specifying the position of the other vehicle in front of the host vehicle from the image acquired by the image acquisition means;
Other vehicle position storage means for storing the position of the other vehicle specified by the other vehicle position specifying means;
Based on the past position of the other vehicle stored in the other vehicle position storage means, the current position of the other vehicle specified by the other vehicle position specifying means, and the travel speed detected by the travel speed detection means, Other vehicle absolute moving speed specifying means for specifying the absolute moving speed;
Based on the position of the other vehicle specified by the other vehicle position specifying means and the absolute movement speed of the other vehicle specified by the other vehicle absolute movement speed specifying means, the parked vehicle position specifying means for specifying the position of the parked vehicle;
Parked vehicle information output means for outputting the position of the parked vehicle specified by the parked vehicle position specifying means and the running speed detected by the running speed detecting means;
The deceleration instruction apparatus according to any one of claims 1 to 3, further comprising: It further has a time interval maximum number storage means for storing the maximum number of time intervals,
The projection control means projects the image by the projecting means when the number of consecutive sections between attention objects passing at a time interval shorter than the determination time is larger than the maximum number of time intervals. The deceleration instruction device according to any one of the above. Attention object information output means for specifying and outputting the position of the attention object in front of the host vehicle and the relative movement speed;
Projecting means for projecting an image onto the road surface ahead of the host vehicle;
A method of instructing the driver to decelerate according to the situation ahead of the host vehicle while traveling,
Determining a decision time;
When the position and relative movement speed of a plurality of attention objects are output by the attention object information output means, the own vehicle reaches each attention object based on the output position and relative movement speed of each attention object. Calculating the required arrival time;
Predicting the time interval at which the vehicle passes each attention object from the calculated arrival times;
Projecting an image instructing deceleration on the road surface ahead of the host vehicle when at least one of the predicted time intervals is shorter than the determined determination time;
A deceleration instruction method comprising:

Images