Patent Publication Number: US-2022237923-A1

Title: Object detection device, object detection method, and storage medium

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is based on and claims the benefit of priority from earlier Japanese Patent Application No. 2019-188278 filed on Oct. 14, 2019, the description of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     Technical Field 
     The present disclosure relates to an object detection device configured to be mounted to an own vehicle to detect an object present around the own vehicle. The present disclosure also relates to an object detection method for detecting an object present around an own vehicle. The present disclosure also relates to storage medium storing an object detection program executed by the object detection device. 
     Related Art 
     An obstacle detection system is known. The obstacle detection system is provided to a vehicle that moves, and detects an obstacle behind the vehicle by using images captured by an imaging section. 
     SUMMARY 
     As an aspect of the present disclosure, an object detection device is configured to be mounted to an own vehicle to detect an object present around the own vehicle. The object detection device includes: 
     a coordinate acquisition section that acquires position coordinates of a detection point corresponding to the object on the basis of a plurality of images captured at different positions along with movement of the own vehicle by one imaging section mounted to the own vehicle; and 
     an object recognition section that recognizes the object without using position coordinates of a movement point that is a detection point corresponding to a moving object but using position coordinates of a stop point that is a detection point different from the movement point. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the accompanying drawings: 
         FIG. 1  is a plan view illustrating a schematic configuration of a vehicle to which an object detection device according to an embodiment is mounted; 
         FIG. 2  is a block diagram illustrating a schematic functional configuration in one embodiment of the object detection device illustrated in  FIG. 1 ; 
         FIG. 3  is a schematic diagram illustrating an example of actions of the object detection device illustrated in  FIG. 2 ; and 
         FIG. 4  is a flow chart illustrating the example of actions of the object detection device illustrated in  FIG. 2 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For example, an obstacle detection system described in JP 2009-180536 A is known. The obstacle detection system is provided to a vehicle that moves, and detects an obstacle behind the vehicle by using images captured by an imaging section. A movement detection section detects the vehicle having moved for a certain distance from the position at which a first image is captured by the imaging section. An image acquisition section acquires the first image and a second image that is an image when the movement detection section detects the vehicle having moved for a certain distance, and supplies the images to an obstacle detection section. The obstacle detection section measures the distance to an object by a motion stereo method using the first and second images. In the motion stereo method, two images captured by one camera at different times and positions are used to detect the three-dimensional position of an object in the images through the principle of triangulation and detect whether the object is an obstacle. 
     The obstacle detection system described in JP 2009-180536 A assumes that an object to be detected is a stationary object when detecting the three-dimensional position of the object in the images through the principle of triangulation in the motion stereo method. Therefore, when the object to be detected is a moving object, the error in three-dimensional position of the object is increased. An object detection result including a large error in three-dimensional position cannot suitably be used for vehicle controls. 
     The present disclosure has been made in view of the circumstances and the like described above. That is, the present disclosure provides, for example, an object detection result that can suitably be used for vehicle controls. 
     Embodiment 
     Hereinafter, an embodiment of the present disclosure will be described with reference to the drawings. Various modified examples that are applicable to one embodiment may possibly inhibit the understanding of the embodiment if inserted in the middle of a series of descriptions about the embodiment. Therefore, modified examples are described not in the middle of a series of descriptions about the embodiment but collectively after the series of descriptions. 
     (Entire Configuration of Vehicle) 
     With reference to  FIG. 1 , a vehicle  10  is a so-called four-wheel automobile and includes a vehicle body  11  having a substantially rectangular shape in plan view. Hereinafter, a virtual line that passes the center in the vehicle width direction of the vehicle  10  and is parallel with the vehicle length direction of the vehicle  10  is referred to as a vehicle central axis line LC. In  FIG. 1 , the vehicle width direction is a left-right direction in the drawing. The vehicle length direction is orthogonal to the vehicle width direction and the vehicle height direction. The vehicle height direction defines the vehicle height of the vehicle  10  and is parallel with a direction in which the gravity acts when the vehicle  10  is stably placed on a horizontal surface in a drivable manner. Further, any direction in which the vehicle  10  moves by drive and which is orthogonal to the vehicle height direction may be referred to as a “translational direction” of the vehicle  10 . 
     For convenience in description, the “front”, the “back”, the “left”, and the “right” of the vehicle  10  are defined as illustrated by arrows in  FIG. 1 . That is, the vehicle length direction is the same meaning as the front-back direction. The vehicle width direction is the same meaning as the left-right direction. The vehicle height direction cannot always be parallel with the direction in which the gravity acts, depending on the conditions for placing or driving the vehicle  10 . In many cases, however, the vehicle height direction is along the direction in which the gravity acts. Therefore, the “translational direction” that is orthogonal to the vehicle height direction can also be referred to as a “horizontal direction”, an “in-plane direction”, an “entry direction”, a “travel direction”, or a “track direction”. 
     A front bumper  13  is attached to a front surface part  12  that is a front end of the vehicle body  11 . A rear bumper  15  is attached to a rear surface part  14  that is a rear end of the vehicle body  11 . A door panel  17  is attached to a side surface part  16  of the vehicle body  11 . In the specific example illustrated in  FIG. 1 , two door panels each on the left and right sides, total four door panels  17  are provided. A door mirror  18  is attached to each of the door panels  17  on the front left and right sides, forming a pair. 
     (Object Detection Device) 
     An object detection device  20  is mounted to the vehicle  10 . The object detection device  20  is configured to be mounted to the vehicle  10  to detect an object B present outside and around the vehicle  10 . Hereinafter, the vehicle  10  to which the object detection device  20  is mounted may be abbreviated as an “own vehicle  10 ”. 
     In the present embodiment, the object detection device  20  includes an imaging section  21 , a sonar sensor  22 , a radar sensor  23 , a vehicle speed sensor  24 , a shift position sensor  25 , a rudder angle sensor  26 , an object detection ECU  27 , a display  28 , and a voice output section  29 . ECU is an abbreviation of Electronic Control Unit. Hereinafter, the components constituting the object detection device  20  are described in detail with reference to  FIGS. 1 and 2 . The electrical connection relationship among the components constituting the object detection device  20  is not illustrated in  FIG. 1  to simplify the illustration. 
     The imaging section  21  is mounted on the own vehicle  10  so as to move with movement of the own vehicle  10  while capturing images of a region around the own vehicle  10 . The imaging section  21  is configured to generate image information corresponding to the images captured of a region around the own vehicle  10 . In the present embodiment, the imaging section  21  is a digital camera device and includes an image sensor such as a CCD or a CMOS. CCD is an abbreviation of Charge Coupled Device. CMOS is an abbreviation of Complementary MOS. 
     In the present embodiment, a plurality of imaging sections  21 , i.e., a front camera CF, a rear camera CB, a left camera CL, and a right camera CR are mounted on the vehicle  10 . When any of the front camera CF, the rear camera CB, the left camera CL, and the right camera CR is not specified, the expression “the imaging section  21 ” in a singular form or “the plurality of imaging sections  21 ” may be used hereinafter. 
     The front camera CF is attached to the front surface part  12  of the vehicle body  11  to acquire image information corresponding to an image in front of the own vehicle  10 . The rear camera CB is attached to the rear surface part  14  of the vehicle body  11  to acquire image information corresponding to an image behind the own vehicle  10 . 
     The left camera CL is attached to the door mirror  18  on the left side to acquire image information corresponding to images on the left side of the own vehicle  10 . The right camera CR is attached to the door mirror  18  on the right side to acquire image information corresponding to images on the right side of the own vehicle  10 . 
     Each of the plurality of imaging sections  21  is connected via an in-vehicle communication line to the object detection ECU  27  to enable information communication. That is, each of the plurality of imaging sections  21  is configured to output the acquired, i.e., generated image information in such a manner as to enable the object detection ECU  27  to receive the image information. 
     The sonar sensor  22  is a ranging sensor that detects the distance to the object B and is attached to the vehicle body  11 . In the present embodiment, the sonar sensor  22  is a so-called ultrasonic sensor and is configured to be capable of transmitting exploratory waves that is ultrasonic waves toward the exterior of the own vehicle  10  and receiving reception waves including ultrasonic waves. That is, the sonar sensor  22  is provided to receive reception waves including reflected waves generated by exploratory waves being reflected on the object B and thereby output ranging information as a result of detecting the distance to a ranging point on the object B. The “ranging point” is a point which is on a surface of the object B and at which exploratory waves transmitted from the sonar sensor  22  are presumed to have been reflected, and is a point corresponding to a “reflection point” for the radar sensor  23 . 
     The object detection device  20  includes at least one sonar sensor  22 . Specifically, a plurality of sonar sensors  22  are provided in the present embodiment. Each of the plurality of sonar sensors  22  is disposed such that it is shifted to either one side from the vehicle central axis line LC in the vehicle width direction. At least one of the plurality of sonar sensors  22  is disposed to transmit exploratory waves along directions crossing the vehicle central axis line LC. 
     Specifically, the sonar sensors  22 , i.e., a first front sonar SF 1 , a second front sonar SF 2 , a third front sonar SF 3 , and a fourth front sonar SF 4  are attached to the front bumper  13 . Similarly, the sonar sensors  22 , i.e., a first rear sonar SR 1 , a second rear sonar SR 2 , a third rear sonar SR 3 , and a fourth rear sonar SR 4  are attached to the rear bumper  15 . Further, the sonar sensors  22 , i.e., a first side sonar SS 1 , a second side sonar SS 2 , a third side sonar SS 3 , and a fourth side sonar SS 4  are attached to the side surface parts  16  of the vehicle  11 . 
     When any of the first front sonar SF 1 , the second front sonar SF 2 , the third front sonar SF 3 , the fourth front sonar SF 4 , the first rear sonar SR 1 , the second rear sonar SR 2 , the third rear sonar SR 3 , the fourth rear sonar SR 4 , the first side sonar SS 1 , the second side sonar SS 2 , the third side sonar SS 3 , and the fourth side sonar SS 4  is not specified, the expression “the sonar sensor  22 ” in a singular form or “the plurality of sonar sensors  22 ” may be used hereinafter. 
     With one sonar sensor  22  referred to as a “first sonar sensor”, and another sonar sensor  22  as a “second sonar sensor”, a “direct wave” and an “indirect wave” are defined as below. The “direct wave” refers to a reception wave received by the first sonar sensor and attributed to a reflected wave generated when an exploratory wave transmitted from the first sonar sensor is reflected on the object B. That is, the direct wave is a reception wave when the sonar sensor  22  that sends an exploratory wave is identical with the sonar sensor  22  that detects, as the reception wave, a reflected wave generated by the exploratory wave being reflected on the object B. In contrast, the “indirect wave” refers to a reception wave received by the second sonar sensor and attributed to a reflected wave generated when an exploratory wave transmitted from the first sonar sensor is reflected on the object B. That is, the indirect wave is a reception wave when the sonar sensor  22  that sends an exploratory wave is different from the sonar sensor  22  that detects, as the reception wave, a reflected wave generated by the exploratory wave being reflected on the object B. 
     The first front sonar SF 1  is provided at a left end on the front surface of the front bumper  13  to transmit exploratory waves toward the front left of the own vehicle  10 . The second front sonar SF 2  is provided at a right end on the front surface of the front bumper  13  to transmit exploratory waves toward the front right of the own vehicle  10 . The first front sonar SF 1  and the second front sonar SF 2  are symmetrically disposed across the vehicle central axis line LC. 
     The third front sonar SF 3  and the fourth front sonar SF 4  are arranged along the vehicle width direction at positions closer to the center on the front surface of the front bumper  13 . The third front sonar SF 3  is disposed between the first front sonar SF 1  and the vehicle central axis line LC in the vehicle width direction to transmit exploratory waves substantially toward the front of the own vehicle  10 . The fourth front sonar SF 4  is disposed between the second front sonar SF 2  and the vehicle central axis line LC in the vehicle width direction to transmit exploratory waves substantially toward the front of the own vehicle  10 . The third front sonar SF 3  and the fourth front sonar SF 4  are symmetrically disposed across the vehicle central axis line LC. 
     As described above, the first front sonar SF 1  and the third front sonar SF 3  that are attached on the left side of the vehicle body  11  are disposed at positions different from each other in plan view. The first front sonar SF 1  and the third front sonar SF 3  adjacent to each other in the vehicle width direction are provided in such a positional relationship that one of the sonars transmits exploratory waves and the other sonar can receive, as reception waves, reflected waves generated by the exploratory waves being reflected on the object B. 
     That is, the first front sonar SF 1  is disposed to be capable of receiving both direct waves corresponding to exploratory waves transmitted by itself and indirect waves corresponding to exploratory waves transmitted by the third front sonar SF 3 . Similarly, the third front sonar SF 3  is disposed to be capable of receiving both direct waves corresponding to exploratory waves transmitted by itself and indirect waves corresponding to exploratory waves transmitted by the first front sonar SF 1 . 
     Similarly, the third front sonar SF 3  and the fourth front sonar SF 4  that are attached closer to the center in the vehicle width direction of the vehicle body  11  are disposed at positions different from each other in plan view. The third front sonar SF 3  and the fourth front sonar SF 4  that are adjacent to each other in the vehicle width direction are provided in such a positional relationship that one of the sonars transmits exploratory waves and the other sonar can receive, as reception waves, reflected waves generated by the exploratory waves being reflected on the object B. 
     Similarly, the second front sonar SF 2  and the fourth front sonar SF 4  that are attached on the right side of the vehicle body  11  are disposed at positions different from each other in plan view. The second front sonar SF 2  and the fourth front sonar SF 4  that are adjacent to each other in the vehicle width direction are provided in such a positional relationship that one of the sonars transmits exploratory waves and the other sonar can receive, as reception waves, reflected waves generated by the exploratory waves being reflected on the object B. 
     The first rear sonar SR 1  is provided at a left end on the rear surface of the rear bumper  15  to transmit exploratory waves toward the rear left of the own vehicle  10 . The second rear sonar SR 2  is provided at a right end on the rear surface of the rear bumper  15  to transmit exploratory waves toward the rear right of the own vehicle  10 . The first rear sonar SR 1  and the second rear sonar SR 2  are symmetrically disposed across the vehicle central axis line LC. 
     The third rear sonar SR 3  and the fourth rear sonar SR 4  are arranged along the vehicle width direction at positions closer to the center on the rear surface of the rear bumper  15 . The third rear sonar SR 3  is disposed between the first rear sonar SR 1  and the vehicle central axis line LC in the vehicle width direction to transmit exploratory waves substantially toward the rear of the own vehicle  10 . The fourth rear sonar SR 4  is disposed between the second rear sonar SR 2  and the vehicle central axis line LC in the vehicle width direction to transmit exploratory waves substantially toward the rear of the own vehicle  10 . The third rear sonar SR 3  and the fourth rear sonar SR 4  are symmetrically disposed across the vehicle central axis line LC. 
     As described above, the first rear sonar SR 1  and the third rear sonar SR 3  that are attached on the left side of the vehicle body  11  are disposed at positions different from each other in plan view. The first rear sonar SR 1  and the third rear sonar SR 3  that are adjacent to each other in the vehicle width direction are provided in such a positional relationship that one of the sonars transmits exploratory waves and the other sonar can receive, as reception waves, reflected waves generated by the exploratory waves being reflected on the object B. 
     That is, the first rear sonar SR 1  is disposed to be capable of receiving both direct waves corresponding to exploratory waves transmitted by itself and indirect waves corresponding to exploratory waves transmitted by the third rear sonar SR 3 . Similarly, the third rear sonar SR 3  is disposed to be capable of receiving both direct waves corresponding to exploratory waves transmitted by itself and indirect waves corresponding to exploratory waves transmitted by the first rear sonar SR 1 . 
     Similarly, the third rear sonar SR 3  and the fourth rear sonar SR 4  that are attached closer to the center in the vehicle width direction of the vehicle body  11  are disposed at positions different from each other in plan view. The third rear sonar SR 3  and the fourth rear sonar SR 4  that are adjacent to each other in the vehicle width direction are provided in such a positional relationship that one of the sonars transmits exploratory waves and the other sonar can receive, as reception waves, reflected waves generated by the exploratory waves being reflected on the object B. 
     Similarly, the second rear sonar SR 2  and the fourth rear sonar SR 4  that are attached on the right side of the vehicle body  11  are disposed at positions different from each other in plan view. The second rear sonar SR 2  and the fourth rear sonar SR 4  that are adjacent to each other in the vehicle width direction are provided in such a positional relationship that one of the sonars transmits exploratory waves and the other sonar can receive, as reception waves, reflected waves generated by the exploratory waves being reflected on the object B. 
     The first side sonar SS 1 , the second side sonar SS 2 , the third side sonar SS 3 , and the fourth side sonar SS 4  are provided to laterally transmit exploratory waves from vehicle side surfaces that are outer surfaces of the side surface parts  16 . Each of the first side sonar SS 1 , the second side sonar SS 2 , the third side sonar SS 3 , and the fourth side sonar SS 4  is provided to be capable of receiving only direct waves. 
     The first side sonar SS 1  is disposed between the door mirror  18  on the left side and the first front sonar SF 1  in the front-back direction to transmit exploratory waves toward the left of the own vehicle  10 . The second side sonar SS 2  is disposed between the door mirror  18  on the right side and the second front sonar SF 2  in the front-back direction to transmit exploratory waves toward the right of the own vehicle  10 . The first side sonar SS 1  and the second side sonar SS 2  are symmetrically provided across the vehicle central axis line LC. 
     The third side sonar SS 3  is disposed between the door panel  17  on the rear left side and the first rear sonar SR 1  in the front-back direction to transmit exploratory waves toward the left of the own vehicle  10 . The fourth side sonar SS 4  is disposed between the door panel  17  on the rear right side and the second rear sonar SR 2  in the front-back direction to transmit exploratory waves toward the right of the own vehicle  10 . The third side sonar SS 3  and the fourth side sonar SS 4  are symmetrically provided across the vehicle central axis line LC. 
     Each of the plurality of sonar sensors  22  is connected via an in-vehicle communication line to the object detection ECU  27  to enable information communication. Each of the plurality of sonar sensors  22  transmits exploratory waves under control of the object detection ECU  27 , generates a signal corresponding to the reception result of reception waves, and outputs the signal in such a manner as to enable the object detection ECU  27  to receive the signal. The information included in the signal corresponding to the reception result of reception waves is referred to as “ranging information” hereinafter. The ranging information includes information on the reception intensity of reception waves and distance information. The “distance information” is information on the distance between each of the plurality of sonar sensors  22  and the object B. Specifically, the distance information includes, for example, information on a time lag from the transmittance of exploratory waves to the reception of reception waves. 
     The radar sensor  23  is a laser radar sensor or a millimeter-wave radar sensor that transmits and receives radar waves and is attached to the front surface part  12  of the vehicle body  11 . The radar sensor  23  is connected via an in-vehicle communication line to the object detection ECU  27  to enable information communication. The radar sensor  23  is configured to generate a signal corresponding to the position and a relative velocity of a reflection point and output the signal in such a manner as to enable the object detection ECU  27  to receive the signal. The “reflection point” is a point which is on a surface of the object B and at which radar waves are presumed to have been reflected. The “relative velocity” is a velocity of the reflection point, i.e., the object B on which radar waves have been reflected, relative to the own vehicle  10 . 
     The vehicle speed sensor  24 , the shift position sensor  25 , and the rudder angle sensor  26  are connected via an in-vehicle communication line to the object detection ECU  27  to enable information communication. The vehicle speed sensor  24  is provided to generate a signal corresponding to a travel velocity of the own vehicle  10  and output the signal in such a manner as to enable the object detection ECU  27  to receive the signal. The travel velocity of the own vehicle  10  is simply referred to as “vehicle speed” hereinafter. The shift position sensor  25  is provided so to generate a signal corresponding to a shift position of the own vehicle  10  and output the signal in such a manner as to enable the object detection ECU  27  to receive the signal. The rudder angle sensor  26  is provided so to generate a signal corresponding to a steering angle of the own vehicle  10  and output the signal in such a manner as to enable the object detection ECU  27  to receive the signal. 
     The object detection ECU  27  is disposed inside the vehicle body  11 . The object detection ECU  27  is a so-called in-vehicle microcomputer, and includes a CPU, a ROM, a RAM, a non-volatile rewritable memory, and the like. Examples of the non-volatile rewritable memory include an EEPROM, a flash ROM, and a hard disk. EEPROM is an abbreviation of Electronically Erasable and Programmable Read Only Memory. The CPU, the ROM, the RAM, and the non-volatile rewritable memory of the object detection ECU  27  are hereinafter simply abbreviated as a “CPU”, a “ROM”, a RAM″, and a “non-volatile storage medium”, respectively. The ROM and the non-volatile storage medium each correspond to a computer-readable non-transitory tangible storage medium. 
     The object detection ECU  27  is configured to be capable of realizing various control actions by the CPU reading a program from the ROM or the non-volatile storage medium and executing the program. This program includes something corresponding to a flow chart or routine described later. The RAM and the non-volatile storage medium are configured to be capable of temporarily storing processing data when the CPU executes the program. In addition, the ROM and/or the non-volatile storage medium preliminarily stores various types of data used when the program is executed. Examples of the various types of data include an initial value, a look-up table, and a map. 
     The object detection ECU  27  is configured to execute an object detection action on the basis of the signals and the information received from each of the plurality of imaging sections  21 , the vehicle speed sensor  24 , the shift position sensor  25 , the rudder angle sensor  26 , and the like. The object detection ECU  27  is also configured to control the actions of the display  28  and the voice output section  29  to perform a notifying action accompanying an object detection state. 
     The display  28  and the voice output section  29  are disposed in a passenger compartment of the vehicle  10 . The display  28  and the voice output section  29  are connected via an in-vehicle communication line to the object detection ECU  27  to enable information communication. That is, the display  28  is configured to display an object detection result and a notifying action accompanying various actions based on the object detection result on a display screen or an indicator. The voice output section  29  is configured to output an object detection result and a notifying action accompanying various actions based on the object detection result by voice output from a speaker. 
     In the present embodiment, the object detection ECU  27  is configured to exhibit drive support functions including a parking support function and a collision avoidance function. Specifically, the object detection ECU  27  is configured to, for example, detect a parking space by using the imaging section  21  and support the movement of the own vehicle  10  into the detected parking space on the basis of an obstacle detection result of the sonar sensor  22  and the like. The “obstacle” refers to, among objects B present around the own vehicle  10 , an object which has a value of height greater than a prescribed threshold and which therefore the own vehicle has difficulty in passing over or it is impossible for the own vehicle to pass over. The object detection ECU  27  is also configured to calculate an acceleration and deceleration control amount and a steering control amount of the own vehicle  10  necessary for traveling a prescribed calculated route while avoiding an obstacle detected using the imaging section  21 . 
     That is, the object detection device  20  is provided to constitute a part of a drive support apparatus  50 . The drive support apparatus  50  includes, in addition to the object detection device  20 , an input operation section  51 , a power control ECU  52 , a braking control ECU  53 , and a steering control ECU  54 . The input operation section  51 , the power control ECU  52 , the braking control ECU  53 , and the steering control ECU  54  are connected via an in-vehicle communication line to the object detection ECU  27  to enable information communication. 
     The input operation section  51  is disposed in the passenger compartment of the vehicle  10 . The input operation section  51  includes switches and/or a voice input section for receiving an input operation by an operator that is an occupant of the vehicle  10 . 
     The power control ECU  52  is provided to control the action of a drive motor and/or an engine (both not illustrated) and thus control the drive output of the vehicle  10 . The braking control ECU  53  is provided to control the drive of a brake actuator (not illustrated) or the like and thus control the braking force of the vehicle  10 . The steering control ECU  54  is provided to control the drive of a steering motor (not illustrated) and thus control the steering amount of the vehicle  10 . 
     (Object Detection ECU) 
     With reference to  FIG. 2 , the object detection ECU  27  has the following functional configuration realized on a microcomputer. That is, the object detection ECU  27  includes an image information acquisition section  270 , a feature point extraction section  271 , and a coordinate acquisition section  272 . The object detection ECU  27  also includes a movement state amount acquisition section  273 , a moving object determination section  274 , a movement point specification section  275 , and a stop point specification section  276 . The object detection ECU  27  also includes a ranging information acquisition section  277 , an object recognition section  278 , and a control content determination section  279 . Hereinafter, the functional configuration of the object detection ECU  27  in the present embodiment will be described in detail. 
     The image information acquisition section  270  is provided to acquire image information corresponding to an image captured of a region around the own vehicle  10 . Specifically, the image information acquisition section  270  is configured to receive from the imaging section  21  image information generated by the imaging section  21  and chronologically hold in the non-volatile storage medium a prescribed volume of the received image information. 
     The feature point extraction section  271  is provided to extract feature points on the captured image on the basis of the image information acquired by the image information acquisition section  270 . The feature points are points featuring the shape of the object B in the captured image and correspond to “detection points”. Specifically, the feature points are discriminative points i.e., pixels in the angle of view of the captured image. For example, the feature points are pixels having a brightness greatly changed from that of a pixel adjacent thereto. The feature points and the technique for extracting the feature points are well-known at the time of filing of the present application. As the technique for detecting the feature points, a well-known technique (such as a Sobel filter, a Laplacian filter, and a Canny method) can be used. Accordingly, the technique for extracting the feature points by the feature point extraction section  271  is not described in detail in the present specification. The “extraction” of the feature points can also be expressed as “detection”. 
     The coordinate acquisition section  272  is provided to acquire the position coordinates of a detection point corresponding to the object B on the basis of a plurality of images captured at different positions of the own vehicle by one imaging section  21  mounted on the own vehicle  10 . The “one imaging section  21 ” is, for example, the front camera CF when the object B present in front of the own vehicle  10  is detected. 
     Specifically, the coordinate acquisition section  272  is configured to calculate the three-dimensional position coordinates of a feature point corresponding to the object B by a motion stereo technique on the basis of a plurality of images captured at different positions of the own vehicle and different times by an identical imaging section  21 . The motion stereo is also referred to as monocular motion stereo or SFM. SFM is an abbreviation of Structure from Motion. The motion stereo or the SFM has been publicly known or well-known at the time of filing of the present application. Accordingly, the motion stereo or the SFM is not described in detail in the present specification. 
     The “detection point” corresponding to the object B, the position coordinates of which are calculated by the coordinate acquisition section  272  is, among feature points extracted by the feature point extraction section  271 , a feature point associated with each of the plurality of images captured at different positions of the own vehicle and different times. Therefore, the “detection point” can also be said as a “feature point”. 
     The movement state amount acquisition section  273  is provided to acquire a movement state amount as a movement velocity or a movement distance of the object B. In the present embodiment, the movement state amount acquisition section  273  is configured to acquire a movement state amount by using an optical flow calculated on the basis of the plurality of images captured at different positions of the own vehicle. 
     The moving object determination section  274  is provided to determine the presence or absence of a moving object that is the object B in a motion state, and the relative positional relationship between the moving object (when present) and the own vehicle  10 , on the basis of the result of acquiring the movement state amount by the movement state amount acquisition section  273 . Specifically, the moving object determination section  274  is configured to determine the presence or absence of a moving object on the basis of a detection state and a distribution state of detection points having a value of the movement state amount greater than a threshold. The moving object determination section  274  is also configured to determine the direction in which a moving object is present with respect to the own vehicle  10 , on the basis of the three-dimensional position or the position in the angle of view of a detection point determined not to be noise but to correspond to the moving object. The detection of a moving object and the calculation of the movement state amount using the optical flow have been publicly known or well-known at the time of filing of the present application. Accordingly, the detection of a moving object and the calculation of the movement state amount using the optical flow are not described in detail in the present specification. 
     The movement point specification section  275  is provided to specify a detection point corresponding to a moving object as a movement point. With reference to  FIG. 3  in addition to  FIGS. 1 and 2 , in the present embodiment, the movement point specification section  275  is configured to specify, as a movement point, a detection point present in a movement point specification range RM that is a prescribed range set according to the relative positional relationship between a moving object and the own vehicle  10 . Specifically, the movement point specification section  275  is configured to set the movement point specification range RM in the direction in which a moving object is present with respect to the own vehicle  10 . 
     The movement point specification section  275  is also configured to variably set the shape of the movement point specification range RM according to the movement state amount. Specifically, the movement point specification section  275  is configured to change the size of the movement point specification range RM according to a movement velocity VB of a moving object or a movement distance DB of a moving object between the previous imaging point and the present imaging point. Aspects of setting the movement point specification range RM will be described in detail in the section of Summary of actions below. 
     The stop point specification section  276  is provided to specify a stop point that is a detection point different from the movement point. The stop point is a detection point corresponding to a stationary object that is the object B in a stationary state. The stop point specification section  276  is configured to remove the movement point from a plurality of acquired detection points to specify a stop point. Specifically, the stop point specification section  276  is configured to remove the movement point from a plurality of detection points, the position coordinates of which are acquired by the coordinate acquisition section  272 , to specify a stop point. 
     The ranging information acquisition section  277  is provided to acquire ranging information that is a result of detecting the distance by the sonar sensor  22 . The ranging information acquisition section  277  is provided to also acquire information on a relative position of the object B with respect to the own vehicle  10  in the translational direction by triangulation based on the ranging information acquired using the plurality of sonar sensors  22 . The ranging information acquisition section  277  is also configured to chronologically hold, in the non-volatile storage medium, the acquired result including the ranging information and the relative position information in a volume corresponding to a prescribed time duration. 
     The object recognition section  278  is provided to recognize the object B on the basis of the position coordinates of a detection point acquired by the coordinate acquisition section  272 . Specifically, the object recognition section  278  is configured to recognize the relative position of the object B with respect to the own vehicle  10  and the three-dimensional shape of the object B on the basis of the positions of detection points corresponding to the object B in an XYZ three-dimensional coordinate system set with reference to a prescribed origin. The “prescribed origin” is, for example, the position of the front camera CF at a prescribed reference time point. The “prescribed reference time point” is, for example, a time point when an object detection action is started by the object detection device  20 . The XYZ three-dimensional coordinate system is, for example, a rectangular coordinate system with reference to the prescribed origin at the prescribed reference time point, with the front set to the X-axis positive direction, the Y-axis positive direction set parallel with the vehicle width direction, and the Z-axis positive direction set parallel with the vehicle height direction. 
     In the present embodiment, the object recognition section  278  is provided to recognize the object B without using the position coordinates of the movement point but using the position coordinates of the stop point. Specifically, the object recognition section  278  is configured to recognize the object B on the basis of the position coordinates of the stop point obtained by removing the coordinates of the movement point from the position coordinates of a plurality of detection points acquired by the coordinate acquisition section  272 . 
     The object recognition section  278  is provided to recognize the object B on the basis of the result of calculating the position coordinates by the coordinate acquisition section  272  and the ranging information and the relative position information acquired by the ranging information acquisition section  277 . That is, in the present embodiment, the object recognition section  278  is configured to detect the object B as an obstacle, using a so-called “sensor fusion” technique that fuses an image recognition result with a ranging result. Specifically, the object recognition section  278  is configured to correct the result of calculating the position coordinates by the coordinate acquisition section  272  on the basis of the ranging information and the relative position information acquired by the ranging information acquisition section  277 , to recognize the position of the object B in the XYZ three-dimensional coordinate system and the shape of the object B. 
     The control content determination section  279  is configured to determine the control contents on the basis of the result of acquiring the ranging information and the relative position information by the ranging information acquisition section  277  and the result of recognizing the object B by the object recognition section  278 . The “control contents” are an acceleration and deceleration control amount and a steering control amount of the own vehicle  10  that are necessary for traveling a prescribed calculated route while avoiding the object B according to the detection result of the object B. The control content determination section  279  is also configured to send the determined control contents via an in-vehicle communication line to the power control ECU  52 , the braking control ECU  53 , and the steering control ECU  54 . 
     (Summary of Actions) 
     Hereinafter, the summary of actions of the object detection device  20  according to the present embodiment, that is, the object detection ECU  27  will be described together with the effects exhibited by the configuration of the present embodiment. 
     Each of the plurality of imaging sections  21 , i.e., the front camera CF, the rear camera CB, the left camera CL, and the right camera CR captures images of a region around the own vehicle  10  and generates image information corresponding the captured images. Each of the plurality of imaging sections  21  also outputs the generated image information in such a manner as to enable the object detection ECU  27  to receive the image information. 
     Each of the plurality of sonar sensors  22  receives reception waves including reflected waves of exploratory waves transmitted toward the exterior of the own vehicle  10  to measure the distance to a point on the object B present around the own vehicle  10 . Each of the plurality of sonar sensors  22  also outputs the acquired ranging information in such a manner as to enable the object detection ECU  27  to receive the ranging information. 
     The radar sensor  23  generates a signal corresponding to the position and a relative velocity of a reflection point on the object B and outputs the signal in such a manner as to enable the object detection ECU  27  to receive the signal. The vehicle speed sensor  24  generates a signal corresponding to a vehicle speed and outputs the signal in such a manner as to enable the object detection ECU  27  to receive the signal. The shift position sensor  25  generates a signal corresponding to a shift position of the own vehicle  10  and outputs the signal in such a manner as to enable the object detection ECU  27  to receive the signal. The rudder angle sensor  26  generates a signal corresponding to a steering angle of the own vehicle  10  and outputs the signal in such a manner as to enable the object detection ECU  27  to receive the signal. 
     The object detection ECU  27  receives the image information from each of the plurality of imaging sections  21 . The object detection ECU  27  also receives the ranging information from each of the plurality of sonar sensors  22 . The object detection ECU  27  also receives the output signals from the radar sensor  23 , the vehicle speed sensor  24 , the shift position sensor  25 , and the rudder angle sensor  26 . The object detection ECU  27  executes an object detection action and a drive support action on the basis of the signals and information received from each of the plurality of sonar sensors  22 , each of the plurality of imaging sections  21 , the vehicle speed sensor  24 , the shift position sensor  25 , the rudder angle sensor  26 , and the like. 
     The image information acquisition section  270  acquires image information corresponding to an image captured of a region around the own vehicle  10  from each of the plurality of imaging sections  21 . The acquired image information is chronologically stored in the non-volatile storage medium. The feature point extraction section  271  extracts feature points on the captured image on the basis of the image information acquired by the image information acquisition section  270 . The coordinate acquisition section  272  acquires the position coordinates of a detection point corresponding to the object B on the basis of a plurality of images captured at different positions along with movement of the own vehicle  10  by one imaging section  21 . 
     Specifically, for example, in cases of detecting the object B present in front of the own vehicle  10 , the image information acquisition section  270  acquires image information corresponding to images captured by the front camera CF and chronologically holds a prescribed volume of the received image information. The coordinate acquisition section  272  calculates, by a motion stereo technique, the position coordinates, i.e., the three-dimensional coordinates, of a feature point that is extracted from images captured by the front camera CF and corresponds to the object B. 
     The movement state amount acquisition section  273  acquires a movement state amount of the object B. Specifically, in the example described above, the movement state amount acquisition section  273  acquires a movement state amount corresponding to the object B in front of the own vehicle  10  by using an optical flow calculated on the basis of the plurality of images captured by the front camera CF. 
     The moving object determination section  274  determines the presence or absence of a moving object that is the object B in a motion state, and the relative positional relationship between the moving object (when present) and the own vehicle  10 , on the basis of the result of acquiring the movement state amount by the movement state amount acquisition section  273 . Specifically, the moving object determination section  274  determines the direction in which a moving object is present with respect to the own vehicle  10 , on the basis of the three-dimensional position or the position in the angle of view of a detection point determined not to be noise but to correspond to the moving object. 
     The movement point specification section  275  specifies a detection point corresponding to a moving object as a movement point. Specifically, with reference to  FIG. 3 , first, the movement point specification section  275  sets a first feature point DP 1  on the object B that has been detected at a previous own vehicle position VP 1 , to a reference point of a movement point specification range RM. The previous own vehicle position VP 1  is a time point when an image of a region in front of the own vehicle  10  is captured by the front camera CF immediately before a present own vehicle position VP 2 . Next, the movement point specification section  275  sets the movement point specification range RM with reference to the reference point. In  FIG. 3 , the movement point specification range RM is set as a rectangle having the reference point in the center thereof. The movement point specification range RM, however, is not limited to this example, and may be set to have a larger area in the travel direction of the object B and on the own-vehicle side. Specifically, as described later, an area in the travel direction of the object B and on the own-vehicle side likely generates a calculation error. Therefore, the movement point specification range RM may be set to be capable of covering such an area. The movement point specification section  275  specifies a detection point present in the movement point specification range RM as a movement point. Setting of the reference point is not limited to the example described above. For example, the center of gravity (or the center) of the area of the object B detected by the front camera CF at the previous own vehicle position VP 1  may be used as the reference point. 
     When the object B is a stationary object, the position of the first feature point DP  1  is not changed between the previous own vehicle position VP 1  and the present own vehicle position VP 2 . The object B that moves at a movement velocity VB, however, moves the first feature point DP 1  to a second feature point DP 2 . 
     Here, the calculation of the position coordinates by motion stereo such as SFM is performed on the assumption that the object B to be calculated is a stationary object. Therefore, calculating the position coordinates of a moving object by the motion stereo increases the calculation error. Particularly, when the detection point, i.e., the feature point, moves along an epipolar line, the calculation error is considerably increased. In addition, the calculation error is increased as the movement velocity VB or the movement distance DB of the moving object is increased. In the example illustrated in  FIG. 3 , the result of calculating the position coordinates is generated in a range surrounded by the dash-dotted line of an ellipse in the drawing which is formed with a detection error candidate point DPE in the center of the ellipse. The detection error candidate point DPE is generated on a virtual line L 1  connecting the position of the front camera CF at the previous own vehicle position VP 1  and the first feature point DP 1 . 
     Therefore, the movement point specification section  275  determines the size of the movement point specification range RM according to the movement velocity VB or the movement distance DB of the moving object. Specifically, the movement point specification section  275  sets the size of the movement point specification range RM larger as the movement velocity VB or the movement distance DB of the moving object is increased. Subsequently, the movement point specification section  275  determines the relative position of the movement point specification range RM with respect to the reference point according to the relative velocity between the own vehicle  10  and the moving object. This procedure enables the movement point specification section  275  to set the movement point specification range RM in the direction in which the moving object is present with respect to the own vehicle  10 . 
     Referring back to  FIG. 2 , a stop point specification section  276  specifies a stop point that is a detection point different from the movement point. Specifically, the stop point specification section  276  removes the movement point from a plurality of detection points acquired by the feature point extraction section  271  and the coordinate acquisition section  272  to specify a stop point. In more detail, the stop point specification section  276  removes the movement point from a plurality of detection points, the position coordinates of which are acquired by the coordinate acquisition section  272 , to specify a stop point. 
     The ranging information acquisition section  277  acquires ranging information corresponding to the object B from each of the plurality of sonar sensors  22 . The ranging information acquisition section  277  also acquires information on a relative position of the object B with respect to the own vehicle  10  on the basis of the ranging information. The ranging information acquisition section  277  chronologically holds the acquired result including the ranging information and the relative position information in a volume corresponding to a prescribed time duration. 
     The object recognition section  278  recognizes the object B on the basis of the result of calculating the position coordinates by the coordinate acquisition section  272  and the ranging information and the relative position information acquired by the ranging information acquisition section  277 . The control content determination section  279  determines the control contents on the basis of the result of acquiring the ranging information and the relative position information by the ranging information acquisition section  277  and the result of recognizing the object B by the object recognition section  278 . The control content determination section  279  sends the determined control contents via an in-vehicle communication line to the power control ECU  52 , the braking control ECU  53 , and the steering control ECU  54 . 
     The object detection device  20  according to the present embodiment, and an object detection method and an object detection program that are executed by the object detection device can exhibit the following effects. Hereinafter, the object detection device  20  according to the present embodiment, and an object detection method and an object detection program that are executed by the object detection device are collectively and simply referred to as the “present embodiment”. 
     In the present embodiment, the object recognition section  278  recognizes the object B present around the own vehicle  10  by a motion stereo technique without using the position coordinates of a movement point that is a detection point corresponding to a moving object but using the position coordinates of a stop point. Specifically, the object recognition section  278  recognizes the object B present around the own vehicle  10  on the basis of the position coordinates of a stop point specified by removing a movement point from a plurality of acquired detection points. In more detail, the object recognition section  278  recognizes the object B on the basis of the position coordinates of a stop point obtained by removing the position coordinates of a movement point from the position coordinates of a plurality of detection points acquired by the coordinate acquisition section  272 . 
     In the detection of the object B using a motion stereo technique, the present embodiment can allow the own vehicle  10  to suitably avoid unnecessary vehicle control accompanying error detection caused by movement of the object B. For example, in cases of parking support or collision avoidance for the own vehicle  10 , when a moving object, i.e., an oncoming vehicle, which the own vehicle  10  can safely pass by is erroneously detected as an obstacle that is likely to collide with the own vehicle, an unnecessary avoidance control or braking control is performed. The present embodiment, however, can suitably avoid the intervention of such an unnecessary avoidance control or braking control. Accordingly, the present embodiment can provide an object detection result that can suitably be used for vehicle controls. 
     In the present embodiment, the object recognition section  278  recognizes the object B on the basis of the result of calculating the position coordinates by the coordinate acquisition section  272  and the ranging information and the relative position information acquired by the ranging information acquisition section  277 . Therefore, even if a moving object whose result of calculating the position coordinates has been deleted, i.e., cleared, approaches the own vehicle  10 , an alert can be issued or a collision avoidance action control can be performed before the occurrence of a collision, by using, for example, the ranging information acquired by the ranging information acquisition section  277 . Accordingly, the present embodiment enables a suitable vehicle drive support control. 
     In the present embodiment, the movement point specification section  275  sets the movement point specification range RM, whose shape is set according to the movement state amount of the object B in a motion state, in the direction in which the moving object is present with respect to the own vehicle  10 . The object recognition section  278  recognizes the object B present around the own vehicle  10  on the basis of the position coordinates of a stop point specified by removing a movement point, the movement point being specified by the movement point specification section  275  by using the movement point specification range RM. Accordingly, the present embodiment can specify, with suitable precision, a movement point according to the movement state amount of the object B, and a stop point. 
     (Example of Actions) 
     Hereinafter, a specific example of actions corresponding to the above-described summary of actions of the present embodiment will be described with reference to a flow chart illustrated in  FIG. 4 . In the drawing, a “step” is simply abbreviated as “S”. 
     The object detection device  20 , i.e., the CPU of the object detection ECU  27 , repetitively activates a routine illustrated in  FIG. 4  at prescribed time intervals while prescribed activation conditions are satisfied. When the routine is activated, the object detection device  20  first executes processing of steps  401  to  407  sequentially. 
     In step  401 , the object detection device  20  acquires image information by using the imaging section  21 . In step  402 , the object detection device  20  extracts feature points on the basis of the acquired image information. In step  403 , the object detection device  20  acquires the position coordinates, i.e., the three-dimensional coordinates, corresponding to the feature points extracted in step  402 . 
     In step  404 , the object detection device  20  calculates an optical flow on the basis of a plurality of images captured at different positions of the own vehicle. In step  405 , the object detection device  20  acquires a movement state amount corresponding to each of the feature points on the basis of the optical flow calculated in step  404 . In step  406 , the object detection device  20  determines the presence or absence of a moving object and the relative positional relationship between the moving object (when present) and the own vehicle  10  on the basis of the movement state amount acquired in step  405 . 
     In step  407 , the object detection device  20  determines the presence or absence of a moving object. When a moving object is present (that is, step  407 =YES), the object detection device  20  executes processing of steps  408  and  409  and then continues to processing of step  410  and following steps. 
     In step  408 , the object detection device  20  sets a movement point specification range RM. In step  409 , the object detection device  20  specifies a movement point by using the set movement point specification range RM. In step  410 , the object detection device  20  specifies a stop point. In this case, the stop point is specified by removing the movement point from a plurality of acquired detection points. 
     When a moving object is not present (that is, step  407 =NO), the object detection device  20  skips the processing of steps  408  and  409  and continues to processing of step  410  and following steps. In step  410 , the object detection device  20  specifies a stop point. In this case, almost all of the plurality of acquired detection points are specified as the stop points. 
     In step  411 , the object detection device  20  acquires ranging information that is a result of detecting the distance by the sonar sensor  22 . In step  411 , the object detection device  20  also acquires information on a relative position of the object B with respect to the own vehicle  10  in the translational direction by triangulation based on the ranging information acquired using the plurality of sonar sensors  22 . 
     In step  412 , the object detection device  20  recognizes the object B on the basis of the result of acquiring the position coordinates in step  403 , and the result of acquiring the ranging information and the relative position information in step  411 . In step  413 , the object detection device  20  determines the control contents on the basis of the result of recognizing the object B in step  412 . 
     Modified Examples 
     The present disclosure is not limited to the above embodiment. Therefore, the above embodiment can be modified as appropriate. Hereinafter, representative modified examples will be described. In the modified examples described below, differences from the above embodiment will be mainly described. Components that are identical or equal to each other between the above embodiment and the modified examples are assigned with the identical sign. Accordingly, in the modified examples described below, the description for the above embodiment can be applied as appropriate to a constituent element having a sign identical to that of the above embodiment, unless technical incompatibility or particularly additional description is noted. 
     The present disclosure is not limited to the specific device configuration illustrated in the above embodiment. That is, for example, the vehicle  10  to which the object detection device  20  is mounted is not limited to four-wheel automobiles. Specifically, the vehicle  10  may be a three-wheel automobile, or a six-wheel or eight-wheel automobile such as a cargo truck. The type of the vehicle  10  may be an automobile having only an internal-combustion engine, an electric automobile or a fuel cell vehicle having no internal-combustion engine, or a so-called hybrid automobile. The shape and the structure of the vehicle body  11  are not also limited to a box shape, that is, a substantially rectangular shape in a plan view. The number of door panels  17  is not also particularly limited. 
     The object to which the object detection device  20  is to be applied is not also particularly limited. That is, for example, the object detection device  20  is not limited to the application thereof to the drive support apparatus  50 . Specifically, for example, the object detection device  20  can also favorably be applied to semi-automated driving or automated driving corresponding to levels  2  to  5  in the definition of automated driving. 
     The imaging section  21  is not limited to the example described above in terms of its position and number. That is, for example, the front camera CF may be disposed in the passenger compartment. Specifically, for example, the front camera CF may be attached to a room mirror (not illustrated) disposed in the passenger compartment of the vehicle  10 . The left camera CL and the right camera CR may be disposed at positions different from the door mirror  18 . Alternatively, the left camera CL and the right camera CR may not be provided. 
     The sonar sensor  22  is not limited to the specific example described above in terms of its position and number. That is, for example, with reference to  FIG. 1 , when the third front sonar SF 3  is disposed at a central position in the vehicle width direction, the fourth front sonar SF 4  is not disposed. Similarly, when the third rear sonar SR 3  is disposed at a central position in the vehicle width direction, the fourth rear sonar SR 4  is not disposed. The third side sonar SS 3  and the fourth side sonar SS 4  may not be disposed. 
     The various sensors used in the object detection device  20  are not limited to the vehicle speed sensor  24 , the shift position sensor  25 , the rudder angle sensor  26 , and the like. That is, for example, at least one of the vehicle speed sensor  24 , the shift position sensor  25 , and the rudder angle sensor  26  may not be disposed or may be replaced with another sensor. 
     In the above embodiment, the object detection ECU  27  has a configuration in which the CPU reads a program from the ROM or the like and activates the program. The present disclosure, however, is not limited to the configuration. That is, for example, the object detection ECU  27  may have a configuration including a digital circuit, e.g., an ASIC or a FPGA, configured to enable the actions described above. ASIC is an abbreviation of Application Specific Integrated Circuit. FPGA is an abbreviation of Field Programmable Gate Array. 
     In the above embodiment, the object detection ECU  27  constitutes a main part of the object detection device  20 . Therefore, the imaging section  21  to the rudder angle sensor  26 , the display  28 , and the voice output section  29  may be, in the above embodiment, regarded not as main constituent elements of the object detection device  20  but as additional elements of the object detection device  20 . Alternatively, for example, at least the imaging section  21  as well as the object detection ECU  27  may be regarded as a main constituent element of the object detection device  20 . 
     The present disclosure is not limited to the specific functional configuration and example of actions illustrated in the above embodiment. For example, the imaging section  21  and the sonar sensor  22  may be regarded as main constituent elements of the object detection device  20  that respectively constitute the image information acquisition section  270  and the ranging information acquisition section  277 . Alternatively, at least one or all of the image information acquisition section  270  to the control content determination section  279  may be provided in the imaging section  21 . 
     The processing contents of the coordinate acquisition section  272  are not limited to monocular motion stereo. Specifically, for example, multiocular stereo, or integrated processing of monocular motion stereo and multiocular stereo may be used. The integrated processing of monocular motion stereo and multiocular stereo has been publicly known or well-known at the time of filing of the present application. Accordingly, in the present specification, the processing of multiocular stereo and the integrated processing of monocular motion stereo and multiocular stereo are not described in detail. 
     The movement state amount acquisition section  273  may acquire a movement state amount by using the detection result of the sonar sensor  22  and/or the radar sensor  23  in place of or together with the optical flow. 
     The movement point specification section  275  may be configured to specify a movement point from feature points, the position coordinates of which have not been calculated by the coordinate acquisition section  272 . Similarly, the stop point specification section  276  may be configured to specify a stop point from feature points, the position coordinates of which have not been calculated by the coordinate acquisition section  272 . In this case, the coordinate acquisition section  272  calculates, by a motion stereo technique, the position coordinates of a stop point obtained by removing, from extracted feature points, a movement point that is a feature point corresponding to a moving object. That is, the coordinate acquisition section  272  acquires the position coordinates of a stop point obtained by removing a movement point from a plurality of acquired detection points, i.e., feature points. The object recognition section  278  recognizes the object B on the basis of the position coordinates of the stop point. Specifically, in the flow chart of  FIG. 4 , the processing of step  403  is performed after step  410 . This processing order can realize high-precision calculation of the position coordinates while effectively reducing calculation load. 
     The ranging information acquisition section  277  may acquire ranging information on the basis of the output of the radar sensor  23  in place of or together with the output of the sonar sensor  22 . That is, ultrasonic waves or electromagnetic waves may be used as the exploratory waves. In addition, a reflection point acquired by the radar sensor  23  may be used as the ranging point. In this case, the relative position information on the reflection point may be used as a replacement of the ranging point acquired by the sonar sensor  22 . Alternatively, the relative position information on the reflection point may be used as a correction element of the ranging point acquired by the sonar sensor  22 . 
     The data on the feature point and/or the position coordinates corresponding to the movement point that is not used for object recognition by the object recognition section  278  may be deleted, i.e., cleared. Alternatively, the data on the feature point and/or the position coordinates corresponding to the movement point may not be deleted but may be held to supply the data for another purpose or use by another ECU. 
     In the specific example described above, the action of detecting the object B using an image captured by the front camera CF has been described. The present disclosure, however, is not limited to this aspect. That is, for example, the present disclosure may also favorably be applied to an action of detecting the object B using an image captured by the rear camera CB. Similarly, the present disclosure may also favorably be applied to an action of detecting the object B using images captured by the left camera CL and the right camera CR. 
     In the above embodiment, an example of using three-dimensional coordinates as the position coordinates has been described. In this example, the “position coordinates” may also be referred to as “three-dimensional position coordinates” or “three-dimensional coordinates”. The present disclosure, however, is not limited to this aspect. That is, for example, two-dimensional coordinates may be used as the position coordinates. Specifically, for example, the coordinate acquisition section  272  may detect, through the principle of triangulation by a motion stereo technique, the position coordinates in an XY two-dimensional coordinate system, with the center of gravity of the own vehicle  10  set to the origin, the vehicle width direction to the X-axis, the vehicle length direction to the Y-axis. Similarly, the movement state amount acquisition section  273  to the control content determination section  279  may be configured to function or act on the basis of the two-dimensional position coordinates. 
     The expression “acquisition” can be replaced as appropriate with similar expressions such as “estimation”, “detection”, “sensing”, and “calculation” without technical incompatibility. The “detection” and the “extraction” can also be replaced with each other as appropriate without technical incompatibility. An inequality sign in the determination processing may be with or without an equality sign. That is, for example, the phrases “less than a threshold” and “a threshold or less” can be replaced with each other without technical incompatibility. 
     Needless to say, the elements constituting the embodiment are not necessarily essential except, for example, cases in which they are particularly clearly described as essential or clearly considered to be essential in principle. In addition, when the numerical values of the number, the amount, the range, and the like of the constituent elements are referred to, the present disclosure is never limited to the specified numerical values except, for example, cases in which they are particularly clearly described as essential or the present disclosure is clearly in principle limited to them. Similarly, when the shape, the direction, the positional relationship, and the like of the constituent elements and the like are referred to, the present disclosure is never limited to the specified shape, direction, positional relationship, and the like except, for example, cases in which they are particularly clearly described as essential or the present disclosure is clearly in principle limited to them. 
     The functional configurations and methods described above may be realized by a dedicated computer that is configured to include a memory and a processor programmed to execute one or a plurality of functions embodied by a computer program. Alternatively, the functional configurations and methods described above may be realized by a dedicated computer configured to include a processor consisting of one or more dedicated hardware logic circuits. Alternatively, the functional configurations and methods described above may be realized by one or more dedicated computers configured by a combination of a memory and a processor programmed to execute one or a plurality of functions, with a processor consisting of one or more hardware logic circuits. The computer program may be stored in a computer-readable non-transitory tangible storage medium as instructions executed by a computer. That is, the device or method according to the present disclosure can be expressed as a computer program including a procedure for realizing the functions or method described above, or as a non-transitory tangible storage medium that stores the program. 
     The modified examples are not also limited to the examples described above. A plurality of modified examples may be combined with each other. In addition, the entire or a part of the above embodiment may be combined with the entire or a part of the modified examples. 
     According to an aspect of the present disclosure, an object detection device ( 20 ) is configured to be mounted to an own vehicle ( 10 ) to detect an object (B) present around the own vehicle. 
     The object detection device includes: 
     a coordinate acquisition section ( 272 ) that acquires position coordinates of a detection point corresponding to the object on the basis of a plurality of images captured at different positions along with movement of the own vehicle by one imaging section ( 21 ) mounted to the own vehicle; and 
     an object recognition section ( 278 ) that recognizes the object without using position coordinates of a movement point that is a detection point corresponding to a moving object but using position coordinates of a stop point that is a detection point different from the movement point. 
     According to another aspect of the present disclosure, an object detection method is a method for detecting an object (B) present around an own vehicle ( 10 ), the method including a following procedure or processing: 
     acquiring position coordinates of a detection point corresponding to the object on the basis of a plurality of images captured at different positions along with movement of the own vehicle by one imaging section ( 21 ) mounted to the own vehicle; and 
     recognizing the object without using position coordinates of a movement point that is a detection point corresponding to a moving object but using position coordinates of a stop point that is a detection point different from the movement point. 
     According to another aspect of the present disclosure, a storage medium ( 27 ) is a medium in which an object detection program that is executed by an object detection device ( 20 ) configured to be mounted to an own vehicle ( 10 ) to detect an object (B) present around the own vehicle is stored to cause a computer ( 27 ) to execute processing, the processing including: 
     acquiring position coordinates of a detection point corresponding to the object on the basis of a plurality of images captured at different positions along with movement of the own vehicle by one imaging section ( 21 ) mounted to the own vehicle; and 
     recognizing the object without using position coordinates of a movement point that is a detection point corresponding to a moving object but using position coordinates of a stop point that is a detection point different from the movement point. 
     In the sections of the application document, elements may be assigned with a reference sign in parenthesis. In this case, the reference sign simply represents one example of the correspondence relationship between the element and a specific component described in the embodiment described above. Therefore, the present disclosure is not at all limited by the reference sign described.