JP2005157765A - Pedestrian detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pedestrian detector capable of detecting pedestrians efficiently, while reducing the amount of processing for detection and preventing misdetections. <P>SOLUTION: The pedestrian detector 100, for detecting pedestrians among objects around own vehicle that include other vehicles, includes a radar device 10 for detecting both other vehicles and the objects including the other vehicles, while changing transmission outputs; a pedestrian position extracting part 30 that provides the subject of determination, by excluding the other vehicles from the objects detected by the radar device 10; an infrared camera 20 that determines whether the subject of determination is a pedestrian; an image-cutting part 32; a pattern comparison part 34; and a pedestrian position storage part 36. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pedestrian detection device that detects a pedestrian on a road.

  2. Description of the Related Art Conventionally, an object detection device that detects an obstacle around a vehicle using a radar is known (see, for example, Patent Document 1). In this object detection device, the distance and direction to an obstacle existing around the vehicle is detected by using a radar, and the result is displayed on the in-vehicle display so as to be superimposed on the own vehicle. The position of the obstacle is clearly recognized.

Conventionally, an infrared monitoring system that detects the presence of a person using infrared rays is known (see, for example, Patent Document 2). In this monitoring system, the temperature change region can be detected by photographing the monitoring region with an infrared camera, and when this temperature change region has a predetermined shape, the temperature change region can be detected as a human being.
JP 7-229961 A (page 3-5, FIG. 1-6) JP-A-6-38217 (page 2-4, FIG. 1-9)

  By the way, when trying to detect the presence of a pedestrian walking around the vehicle using the object detection device disclosed in Patent Document 1 described above, it is necessary to set the radar output high. There is a problem in that an object is included in the detection target and pedestrians cannot be detected efficiently.

  It is also conceivable to combine such an object detection device and the infrared monitoring system disclosed in Patent Document 2 to determine whether or not a person is a pedestrian using an infrared camera for an object detected by a radar. . However, as described above, when setting the radar output capable of detecting a pedestrian in the object detection device, the number of detected objects increases. Therefore, walking is performed using an infrared camera for all detected objects. There is a problem that it takes a long time to detect a person because the processing load is large. Moreover, when the object detected by the object detection device is a vehicle, there is a problem that a passenger of this vehicle may be erroneously detected as a pedestrian.

  The present invention was created in view of the above points, and its purpose is to reduce the amount of processing for detection, efficiently detect pedestrians in a short time, and to detect false detections. It is in providing the pedestrian detection apparatus which can prevent.

  In order to solve the above-described problem, the pedestrian detection device according to the present invention detects a pedestrian from objects including other vehicles existing around the host vehicle. Means, an object detection means for detecting an object, and other vehicles detected by the vehicle detection means are excluded from the objects detected by the object detection means as a determination target. Pedestrian determination means for determining whether or not. Since it is determined whether other objects excluding other vehicles are pedestrians as determination objects, the number of determination objects can be reduced, and pedestrians can be detected efficiently in a short time. In addition, since other vehicles are excluded from the determination target in advance, the vehicle passenger is not erroneously detected as a pedestrian, and erroneous detection can be prevented.

  Further, the pedestrian determination means described above includes a camera that images the determination object using infrared rays, and a comparison means that compares whether the image of the determination object captured by the infrared camera matches a human-specific image. It is desirable to provide. This makes it possible to reliably determine only pedestrians included in the determination object.

  Further, the above-described camera is an infrared camera, and it is desirable that the image unique to the human being has a human-specific infrared emission pattern. Thereby, it becomes possible to reliably determine the pedestrian included in the determination target object with high accuracy.

  The vehicle detection means described above includes a transmitter that outputs a predetermined exploration wave, a receiver that receives a reflected wave with respect to the exploration wave from another vehicle, and a position of the other vehicle based on the exploration wave and the reflected wave. It is desirable to be configured using a first radar apparatus having a control unit to be obtained. Alternatively, the object detection means described above includes a transmitter that outputs a predetermined exploration wave, a receiver that receives a reflected wave with respect to the exploration wave by the object, and a control for obtaining the position of another vehicle based on the exploration wave and the reflected wave. It is desirable to be configured using a second radar device having a unit. Thereby, the position of the other vehicle which exists in the circumference | surroundings of the own vehicle, and the object containing this other vehicle can be detected easily.

  The vehicle detection means and the object detection means described above are based on a transmitter that outputs a predetermined exploration wave, a receiver that receives a reflected wave for the exploration wave from another vehicle or object, and the exploration wave and the reflected wave. It is configured using a common radar device having a control unit for determining the position of another vehicle or object, and by setting the transmission output of the exploration wave output from the transmitter to small or large, vehicle detection means or It is desirable to use a radar device as the object detection means. By simply switching the transmission output, a common radar apparatus can be used as the vehicle detection means and the object detection means, so that the entire apparatus can be simplified and the cost can be reduced.

  Hereinafter, a pedestrian detection apparatus according to an embodiment to which the present invention is applied will be described in detail with reference to the drawings.

  Drawing 1 is a figure showing the composition of the pedestrian detection device of one embodiment. A pedestrian detection device 100 shown in FIG. 1 is mounted on a vehicle and detects a pedestrian existing around the vehicle (own vehicle). In addition, this pedestrian does not include passengers of other vehicles existing around the host vehicle. As shown in FIG. 1, the pedestrian detection device 100 includes a radar device 10, an infrared camera 20, a pedestrian position extraction unit 30, an image extraction unit 32, a pattern comparison unit 34, a pedestrian position storage unit 36, and a display image generation. The unit 40 and the display device 42 are included.

  The radar apparatus 10 detects an object included in the search wave transmission range by transmitting a predetermined search wave and receiving the reflected wave. For example, an object existing in each angular direction can be detected by transmitting a survey wave simultaneously in a plurality of angular directions. For this purpose, the laser device 10 includes a transmitter 12, a receiver 14, and a control unit 16. The transmitter 12 outputs a plurality of exploration waves in parallel. As the exploration wave, highly directional radio waves such as millimeter waves, light, or ultrasonic waves are used. The number of exploration waves to be output is determined in consideration of the detection range and detection resolution. The receiver 14 receives the reflected wave returned from the probe wave output from the transmitter 12 reflected by an object existing in the transmission direction. The control unit 16 obtains the position (distance) of the object by comparing the transmitted exploration wave and the intensity of the reflected wave. In this embodiment, since the direction of transmission of each exploration wave output in parallel is fixed, only the distance of the object corresponding to each exploration wave is obtained by calculation, and the direction of this object is a predetermined direction. A set value is used. Note that a radar device that transmits one exploration wave may be used to detect an object that exists in the rotation range by receiving a reflected wave while mechanically rotating the direction of the exploration wave transmission.

  Further, in the present embodiment, by switching the transmission output (output power) of the exploration wave output from the transmitter 12 of the radar apparatus 10, the vehicle detection unit that mainly detects other vehicles and the other vehicles are used. The radar apparatus 10 is caused to perform both operations of the object detection means for detecting objects other than those. Specifically, when it is desired to operate the radar apparatus 10 as a vehicle detection means, a reflected wave that can be detected only for a vehicle or a large object (such as a signboard) of the same size by setting the transmission output small. To receive. On the other hand, when it is desired to operate the radar apparatus 10 as an object detection means, the transmission output can be set to be large so that not only a vehicle or a large object of the same size but also a pedestrian and other small objects can be detected. Make it possible to receive reflected waves.

  The infrared camera 20 has a predetermined shooting range and takes an infrared image emitted from an object included in the shooting range. The pedestrian position extraction unit 30 extracts a pedestrian position by excluding vehicles detected by reducing the transmission output from a plurality of objects detected by increasing the transmission output of the laser device 10. The extracted pedestrian position is stored in the pedestrian position storage unit 36. Note that the pedestrian position extracted here does not accurately indicate the position of the pedestrian, but was detected by increasing the transmission output from among the objects detected by decreasing the transmission output. By excluding large objects such as vehicles that are clearly different from pedestrians, the purpose is to narrow down (decrease) the number of objects to be determined for determining whether each object to be performed later is a pedestrian Therefore, noise other than pedestrians is also included. Therefore, precisely, it should be called a pedestrian candidate position.

  The image cutout unit 32 cuts out an image corresponding to the pedestrian position extracted by the pedestrian position extraction unit 30 from the infrared video imaged by the infrared camera 20. The pattern comparison unit 34 performs pattern comparison between a cut-out image corresponding to each pedestrian position cut out by the image cut-out unit 32 and a preset human-specific image. That is, when a person is photographed with the infrared camera 20, the temperature of the face exposed from the clothes is high, and the clothes part is at a lower temperature and higher than the temperature of an object other than humans. Will have a pattern. It also has a human-specific shape pattern that combines the head and upper body. By preparing images corresponding to these human-specific patterns (temperature patterns, shape patterns) in advance and comparing them with images cut out corresponding to each pedestrian position photographed by the infrared camera 20, An object having a large degree of coincidence can be determined as a human. Since the vehicle is excluded when the pedestrian position extraction unit 30 extracts the pedestrian position, the human being detected by the pattern comparison unit 34 includes only pedestrians other than the passengers of the vehicle. become.

  The pedestrian position storage unit 36 stores the pedestrian position extracted by the pedestrian position extraction unit 30, and then removes the pedestrian position corresponding to other than the pedestrian as noise by the pattern comparison unit 34. Thereby, finally, only the pedestrian position corresponding to the true pedestrian is stored in the pedestrian position storage unit 36.

  The display image generation unit 40 displays the position of the vehicle detected by reducing the transmission output of the radar device 10 and the true pedestrian position determined by the pattern comparison unit 34 based on the position of the own vehicle. The displayed image is generated and displayed on the display device 42.

  The radar device 10 described above serves as vehicle detection means and object detection means, and the infrared camera 20, pedestrian position extraction unit 30, image cutout unit 32, pattern comparison unit 34, and pedestrian position storage unit 36 serve as pedestrian determination means. The pattern comparison unit 34 corresponds to the comparison unit.

  The pedestrian detection apparatus 100 of this embodiment has such a configuration, and the operation thereof will be described next.

  FIG. 2 is a flowchart showing a series of operation procedures related to pedestrian detection by the pedestrian detection apparatus 100. First, the control unit 16 in the radar apparatus 10 sets the transmission output of the transmitter 12 to a low output and transmits a search wave, and based on the reflected wave received by the receiver 14, The position (distance and direction) of another vehicle (including a large object similar to the vehicle) is detected (step 100). In addition, the control unit 16 in the radar apparatus 10 sets the transmission output of the transmitter 12 to a high output to transmit the exploration wave, and based on the reflected wave received by the receiver 14, The position (distance and direction) of an object including other vehicles is detected (step 101).

  Next, the pedestrian position extraction unit 30 extracts the pedestrian position as the determination target object by excluding the vehicle detected in step 100 from the objects detected in step 101 (step 102).

  3 and 4 are explanatory diagrams of the pedestrian position extraction operation. FIG. 3 shows the vehicle detection result in step 100. Since the transmission output of the radar apparatus 10 is set to be small, the number of detected objects (symbol □ represents a vehicle) is small. FIG. 4 shows the detection result of the vehicle and other objects in step 101. Since the transmission output of the radar apparatus 10 is set to be large, the number of detected objects (□, ○, and Δ respectively represent vehicles, pedestrians, and noise) is large. Among the detection results shown in FIG. 4, the object corresponding to the detection result shown in FIG. 3 (the vehicle represented by the symbol □) is excluded from the pedestrian position as the determination target (× Symbol).

  Next, when photographing by the infrared camera 20 is performed (step 103), the image cutout unit 32 corresponds to the pedestrian position extracted by the pedestrian position extracting unit 30 from the photographed infrared image. A partial image is cut out (step 104).

  Next, the pattern comparison unit 34 compares the cut-out partial image with a human-specific image pattern, and whether or not they match, that is, the cut-out partial image corresponds to a human (pedestrian). It is determined whether or not there is (step 105). If they do not match, a negative determination is made, and then the pedestrian position storage unit 36 removes the pedestrian position corresponding to the mismatched partial image as noise (step 106). After this noise removal is performed, or after a match determination is made as a result of the comparison operation by the pattern comparison unit 34 and an affirmative determination is made in step 105, the pattern comparison unit 34 determines all pedestrian positions. It is determined whether or not a comparison operation has been performed (step 107). If there is a pedestrian position that has not been compared, a negative determination is made, and the process returns to step 105 to perform a comparison operation for the next pedestrian position.

  Further, when the comparison operation for all pedestrian positions is completed, an affirmative determination is made in the determination of step 107, and then the display image generation unit 40 causes the display device 42 to use the own vehicle position as a reference. The positions of other vehicles and pedestrians in the vicinity are displayed (step 108). Thus, a series of operation | movement until it detects a pedestrian position and displays the position is complete | finished.

  As described above, in the pedestrian detection apparatus 100 according to the present embodiment, since it is determined whether other objects excluding other vehicles around the host vehicle are pedestrians, the number of determination objects is reduced. It is possible to detect a pedestrian efficiently in a short time. In addition, since other vehicles are excluded from the determination target in advance, the vehicle passenger is not erroneously detected as a pedestrian, and erroneous detection can be prevented.

  In addition, it is included in the determination object by comparing whether or not the image of the determination object captured by the infrared camera 20 matches a human-specific image pattern and determining whether or not each determination object is a pedestrian. It is possible to reliably determine only pedestrians who are able to travel with high accuracy. In addition, by using the radar apparatus 10, it is possible to easily detect the position of another vehicle existing around the own vehicle or an object including the other vehicle.

  Moreover, since both the detection of the vehicle and the detection of other objects including the vehicle are performed by switching the transmission output of the radar device 10, the common radar device 10 can be used for two types of detection applications. The entire apparatus can be simplified, and the cost can be reduced.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. In the above-described embodiment, it is determined whether or not each partial image obtained by cutting out the infrared video imaged by the infrared camera 20 is a pedestrian, but a normal camera having light receiving sensitivity to visible light is used. May be. In this case, since a comparison using a light emission pattern based on a human-specific temperature cannot be performed, it is determined whether a partial image corresponds to a pedestrian by performing a comparison using a human-specific shape pattern. The

  In the above-described embodiment, an image representing the pedestrian position is generated using the detection result of the pedestrian position, but other operations may be performed using the detection result. For example, a predetermined warning operation or an operation for assisting automatic driving for avoiding danger may be performed when the distance to the pedestrian around the host vehicle becomes a predetermined value or less.

It is a figure which shows the structure of the pedestrian detection apparatus of one Embodiment. It is a flowchart which shows a series of operation | movement procedures regarding the pedestrian detection by a pedestrian detection apparatus. It is explanatory drawing of extraction operation | movement of a pedestrian position. It is explanatory drawing of extraction operation | movement of a pedestrian position.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Radar apparatus 12 Transmitter 14 Receiver 16 Control part 20 Infrared camera 30 Pedestrian position extraction part 32 Image extraction part 34 Pattern comparison part 36 Pedestrian position storage part 40 Display image generation part 42 Display apparatus 100 Pedestrian detection apparatus

Claims (6)

A pedestrian detection device for detecting a pedestrian from objects including other vehicles existing around the host vehicle,
Vehicle detection means for detecting the other vehicle;
Object detection means for detecting the object;
Pedestrian determination for determining whether or not the object to be detected is a pedestrian by excluding the other vehicle detected by the vehicle detection unit from the object detected by the object detection unit Means,
A pedestrian detection device comprising: In claim 1,
The pedestrian determination means includes
A camera for photographing the determination object using infrared rays;
A comparison means for comparing whether or not the image of the determination object photographed by the infrared camera matches a human-specific image;
A pedestrian detection device comprising: In claim 2,
The pedestrian detection apparatus according to claim 1, wherein the camera is an infrared camera, and the human-specific image is a human-specific infrared light emission pattern. In any one of Claims 1-3,
The vehicle detection means includes: a transmitter that outputs a predetermined exploration wave; a receiver that receives a reflected wave with respect to the exploration wave by the other vehicle; and the other vehicle based on the exploration wave and the reflected wave. A pedestrian detection device comprising a first radar device having a control unit for obtaining a position. In any one of Claims 1-4,
The object detection means includes a transmitter for outputting a predetermined exploration wave, a receiver for receiving a reflected wave with respect to the exploration wave by the object, and a control for obtaining the position of the object based on the exploration wave and the reflected wave. A pedestrian detection device comprising: a second radar device having a unit. In any one of Claims 1-3,
The vehicle detection means and the object detection means include a transmitter that outputs a predetermined exploration wave, a receiver that receives a reflected wave with respect to the exploration wave from the other vehicle or the object, the exploration wave and the reflected wave. Is configured using a common radar device having a control unit for determining the position of the other vehicle or the object based on
A pedestrian detection apparatus using the radar apparatus as the vehicle detection means or the object detection means by setting the transmission output of the exploration wave output from the transmitter to small or large.

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