Patent Publication Number: US-2022229179-A1

Title: Obstacle detection device and obstacle detection method

Description:
INCORPORATION BY REFERENCE 
     The present application claims priority under 35 U.S.C. § 119 to Japanese Patent Application No. 2021-006345 filed on Jan. 19, 2021. The content of the application is incorporated herein by reference in its entirety. 
     BACKGROUND OF THE INVENTION 
     Field of the Invention 
     The present invention relates to an obstacle detection device and an obstacle detection method. 
     Description of the Related Art 
     Conventionally, a device has been known that detects an object existing around a vehicle and determines whether or not the detected object is an obstacle that obstructs a vehicle traveling along a parking path. 
     For example, Japanese Patent Laid-Open No. 2018-180909 discloses an obstacle detection and notification device including a moving obstacle detection unit that detects a moving obstacle in a monitoring region, a first calculation unit that calculates a movement prediction path of the moving obstacle, a second calculation unit that calculates a movement prediction path of an own vehicle, a removal unit that removes a moving obstacle that is less likely to lead to a warning execution region from a warning target moving obstacle based on the movement prediction path of the moving obstacle and the movement prediction path of the own vehicle, and a warning unit that notifies the warning target moving obstacle of a warning. 
     SUMMARY OF THE INVENTION 
     However, the number of objects to be detected is large and it may be erroneously determined that an object contacts or collides with the vehicle, so that the vehicle may stop traveling. If the vehicle stops traveling, a parking path is recalculated. Thus, there is a problem that it takes time to park the vehicle. 
     The present invention is directed to providing an obstacle detection device and an obstacle detection method in which a detection accuracy of an obstacle that obstructs a traveling vehicle is improved to shorten a time period required until the vehicle is parked. 
     To attain the above-described object, an obstacle detection device according to an aspect of the present invention includes an input interface connected to an external device, an acquisition unit configured to acquire path information as information about a parking path to a parking position where a vehicle is to be parked and range information representing a position and a range of an object existing around the vehicle, an operation control unit configured to generate a driving signal according to the path information acquired by the acquisition unit and outputs the generated driving signal to a traveling driving unit configured to travel the vehicle, the driving signal being for operating the traveling driving unit, an inside/outside determination unit configured to determine, when receiving surroundings information representing a situation around the vehicle from the external device via the input interface, whether an object included in the received surroundings information is an object positioned inside the range represented by the range information acquired by the acquisition unit or an object positioned outside the range, and an obstacle determination unit configured to determine whether or not the object that has been determined to be positioned outside the range by the inside/outside determination unit is an obstacle to the vehicle traveling in the parking path. 
     The aspect of the present invention makes it possible to improve a detection accuracy of an obstacle that obstructs a traveling vehicle to shorten a time period required until the vehicle is parked. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram illustrating a configuration of an in-vehicle apparatus; 
         FIG. 2  is a diagram illustrating a state where an own vehicle and a situation around the own vehicle are viewed from the top; 
         FIG. 3  is a diagram illustrating a position of a detection point detected by a sonar unit; 
         FIG. 4  is a diagram illustrating an example of a peripheral map; 
         FIG. 5  is a diagram illustrating an example of an obstacle map; 
         FIG. 6  is a diagram illustrating an example of an obstacle map and a diagram illustrating a determination point set in a parking path; 
         FIG. 7  is a diagram illustrating an example of an obstacle map and a diagram illustrating an own vehicle graphic; 
         FIG. 8  is a flowchart illustrating an operation of an obstacle detection device; 
         FIG. 9  is a flowchart illustrating an operation of the obstacle detection device; and 
         FIG. 10  is a block diagram illustrating a configuration of a modification of the obstacle detection device. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     An embodiment of the present invention will be described below with reference to the accompanying drawings. 
       FIG. 1  is a diagram illustrating a configuration of an in-vehicle apparatus  3  mounted on a vehicle. In the following description, the vehicle having the in-vehicle apparatus  3  mounted thereon is referred to as an own vehicle  1 A. 
     The in-vehicle apparatus  3  has a configuration in which a position detection unit  10 , a sonar unit  30 , a path generation device  50 , an obstacle detection device  100 , and a traveling driving device  150  are connected to one another via a communication bus  5 . The communication bus  5  is a bus for data communication according to a standard such as Ethernet (registered trademark), a CAN (controller area network), or an LIN (local interconnect network). 
     The position detection unit  10  detects a position of the own vehicle  1 A. The position detection unit  10  includes a GNSS (global navigation satellite system) receiver and a processor (Neither is illustrated). The GNSS receiver receives a signal to be transmitted from a satellite. The processor operates a longitude and a latitude as position information of the own vehicle  1 A based on the signal received by the GNSS receiver and an orientation of the own vehicle  1 A due to a difference in calculated position information. The position detection unit  10  outputs operated position information and orientation information of the own vehicle  1 A to the path generation device  50 . 
     The sonar unit  30  is mounted on a plurality of portions such as the front, the rear, the left, and the right of the own vehicle  1 A, and detects an object existing around the own vehicle  1 A using an ultrasonic wave. Specifically, the sonar unit  30  detects information about a distance to the object and an orientation based on the own vehicle  1 A, for example. The sonar unit  30  outputs sensor data representing a sensing result to the path generation device  50  and the obstacle detection device  100 . 
     Although a case where the in-vehicle apparatus  3  includes a sonar will be described, a sensor mountable on the in-vehicle apparatus  3  is not limited to the sonar. For example, a radar and a lidar (LIDAR: laser imaging detection and ranging) capable of measuring a distance from an object using a radio wave, light, or the like may be mounted on the in-vehicle apparatus  3 . A camera may be mounted on the in-vehicle apparatus  3 . 
     The path generation device  50  is a computer device including an input/output interface (the interface is hereinafter abbreviated as I/F)  60  (CAN transceiver, transceiver, Ethernet PHY), a memory  70 , and a processor  80  (first processor). The path generation device  50  may be configured to include a storage device such as an HDD (hard disk drive) and an SSD (solid state drive), for example, in addition to the devices. 
     The input/output I/F  60  is connected to the communication bus  5 , and performs data communication with an external device connected to the communication bus  5 . The external device includes the position detection unit  10 , the sonar unit  30 , and the obstacle detection device  100 . 
     The memory  70  includes a ROM (read only memory) and a RAM (random access memory). The memory  70  may include a nonvolatile semiconductor memory such as a flash memory. The memory  70  stores a computer program to be executed by the processor  80 , data to be processed when the processor  80  executes the computer program, and data representing a processing result. The memory  70  stores sensor data outputted by the sonar unit  30 . 
     The processor  80  includes a CPU (central processing unit) and an MPU (microprocessor unit). 
     The path generation device  50  includes a position acquisition unit  81 , a situation acquisition unit  82 , a map generation unit  83 , a parking position determination unit  84 , a parking path generation unit  85 , and an operation information generation unit  86 , respectively, as functional components. Each of the functional components is a function to be implemented when the processor  80  performs an operation according to the computer program. 
     The position acquisition unit  81  receives the position information and the orientation information of the own vehicle  1 A calculated by the position detection unit  10 . The position acquisition unit  81  corrects the position information and the orientation information received from the position detection unit  10  using a well-known dead reckoning method. The position acquisition unit  81  outputs the corrected position information and orientation information to the map generation unit  83 . The position acquisition unit  81  outputs the corrected position information and orientation information to the obstacle detection device  100 . The position information and the orientation information will be hereinafter referred to as position and orientation information. 
     The situation acquisition unit  82  causes the sonar unit  30  to perform sensing, and acquires sensor data as a detection result of the sonar unit  30  as surroundings information. The situation acquisition unit  82  causes the memory  70  to temporarily store the acquired sensor data. 
     The map generation unit  83  generates peripheral map  200  (see  FIG. 4 ) representing a situation around the own vehicle  1 A based on the position and orientation information received from the position acquisition unit  81  and the sensor data acquired from the memory  70 . In the peripheral map  200 , a position of the own vehicle  1 A, a position of an object existing around the own vehicle  1 A and a distance to the object, and a position of a parking frame such as a white line painted on a road surface of a parking lot, for example, are recorded. The object to be recorded on the peripheral map  200  includes other vehicles and structures such as a pillar and a wall of the parking lot, for example. The object is hereinafter referred to as a target object. The parking frame is painted on the road surface in a predetermined thickness, whereby a spacing corresponding to the thickness of the white line is detected as a periodical feature. 
     The map generation unit  83  generates, when recording a position and a range of a detected target object on the peripheral map  200 , a range graphic representing the range of the target object, and records the generated range graphic on the peripheral map  200 . The range graphic to be generated by the map generation unit  83  will be described with reference to  FIGS. 2 to 4 .  FIG. 2  is a diagram illustrating the own vehicle  1 A and a situation around the own vehicle  1 A as viewed from the top. 
     As illustrated in  FIG. 2 , three parking regions  201 ,  202 , and  203  exist on the right side of the own vehicle  1 A, and a wall  220  is installed on the left side of the own vehicle  1 A. Another vehicle  1 B is parked in the parking region  201 , and another vehicle  1 C is parked in the parking region  203 . In  FIG. 2 , a position of the own vehicle  1 A is referred to as a position S 0 . The position S 0  represents a reference position of the own vehicle  1 A. The reference position is a previously set position of the own vehicle  1 A, and may be a center position in a vehicle width direction of a front wheel or a rear wheel, a position of a center of gravity of the own vehicle  1 A, or a center position in a vehicle length direction and the vehicle width direction, for example. 
       FIG. 3  is a diagram illustrating a position of a detection point T detected by the sensor data from the sonar unit  30  until the own vehicle  1 A moves to the position S 0  illustrated in  FIG. 2 . In an example illustrated in  FIG. 3 , a case is illustrated where T 1 , T 2 , T 3 , and T 4  are detected as a detection point T of the other vehicle  1 B and T 11 , T 12 , T 13 , and T 14  are detected as a detection point T of the other vehicle  1 C. A case is illustrated where T 21 , T 22 , T 23 , T 24 , T 25 , and T 26  are detected as a detection point T of the wall  220 .  FIG. 3  does not illustrate all the detection points T detected by the sensor data from the sonar unit  30 , but the sonar unit  30  actually detects a target object with more detailed accuracy. 
       FIG. 4  is a diagram illustrating one example of the peripheral map  200  generated by the map generation unit  83 . 
     A coordinate system having the position S 0  of the own vehicle  1 A as an origin and having an x-axis and a y-axis as two axes perpendicular to each other is set in the peripheral map  200 . The x-axis is a direction parallel to the vehicle length direction of the own vehicle  1 A, and the y-axis is a direction parallel to the vehicle width direction of the own vehicle  1 A. The position S 0  of the own vehicle  1 A is a position represented by the position and orientation information acquired by the position acquisition unit  81 . On the peripheral map  200 , rectangular range graphics  211 ,  213 , and  225  generated by the map generation unit  83  based on coordinates of the detection point T are recorded. 
     The range graphic  211  is a rectangular graphic representing a range of the other vehicle  1 B as a target object, the range graphic  213  is a rectangular graphic representing a range of the other vehicle  1 C as a target object, and the range graphic  225  is a rectangular graphic representing a range of the wall  220  as a target object. 
     Although graphics corresponding to specific shapes of the other vehicle  1 B, the other vehicle  1 C, and the wall  220  may be respectively generated as the range graphics  211 ,  213 , and  225  each representing the range of the target object, a processing load of the path generation device  50  increases, and it takes time to perform processing for generating the graphics. Accordingly, the map generation unit  83  collects sensor data that can be determined as data which one target object has been detected among sensor data into one, to generate the range graphics  211 ,  213 , and  225  each representing the range of the target object. The map generation unit  83  determines that data in which the interval between the positions indicated by the sensor data is equal to or less than a previously set distance is data of one object. 
     The map generation unit  83  selects the detection points T respectively representing a maximum value and a minimum value in an x-axis direction and a maximum value and a minimum value in a y-axis direction for each of the target objects. 
     For the other vehicle  1 B, for example, T 1  is selected as the detection point T representing the maximum value in the x-axis direction, and T 3  or T 4  is selected as the detection point T representing the minimum value in the x-axis direction. T 4  is selected as the detection point T representing the maximum value in the y-axis direction, and T 2  is selected as the detection point T representing the minimum value in the y-axis direction. 
     The map generation unit  83  generates the rectangular range graphics  211 ,  213 , and  225  based on the coordinates of the selected detection point T. For example, the map generation unit  83  generates a graphic constitute by a first side passing through the detection point T 1  representing the maximum value in the x-axis direction and parallel to the y-axis, a second side passing through the detection point T 3  representing the minimum value in the x-axis direction and parallel to the y-axis, a third side passing through the detection point T 4  representing the maximum value in the y-axis direction and parallel to the x-axis, and a fourth side passing through the detection point T 2  representing the minimum value in the y-axis direction and parallel to the x-axis as the range graphic  211  representing the range of the other vehicle  1 B. 
     The range graphic  211  is a graphic having a point A (xa, ya), a point B (xb, yb), a point C (xc, yc), and a point D (xd, yd) illustrated in  FIG. 4 , respectively, as four vertexes. 
     The range graphic  213  is a graphic having a point E (xe, ye), a point F (xf, yf), a point G (xg, yg), and a point H (xh, yh), respectively, as four vertexes. 
     The range graphic  225  is a graphic having a point I (xi, yi), a point J (xj, yj), a point K (xk, yk), and a point L (xl, yl), respectively, as four vertexes. 
     If the own vehicle  1 A is positioned at the position S 0  illustrated in  FIGS. 2 to 4 , respective positions on surfaces, on the opposite side to the side facing the own vehicle  1 A, of the other vehicles  1 B and  1 C cannot be measured with high accuracy in the sensor data from the sonar unit  30 . Similarly, if the own vehicle  1 A is positioned at the position S 0 , a position on a surface, on the opposite side to the side facing the own vehicle  1 A, of the wall  220  cannot be measured. However, the respective positions on the surfaces, on the opposite side to the side facing the own vehicle  1 A, of the other vehicles  1 B and  1 C and the wall  220  are not required to have an accuracy from the viewpoint of collision detection, and therefore previously set values may be respectively set. For example, a y-coordinate value of the point B of the range graphic  211  may be set to a value obtained by adding or subtracting the previously set value to or from a y-coordinate value of the point A (xa, ya), and a y-coordinate value of the point D of the range graphic  211  may be set to a value obtained by adding or subtracting a previously set value to or from a y-coordinate value of the point C (xc, yc). 
     The parking position determination unit  84  refers to the peripheral map  200  generated by the map generation unit  83 , to determine a parking frame in which the own vehicle  1 A is to be parked. For example, the parking position determination unit  84  selects a parking frame in which a target object is not detected and a distance from the own vehicle  1 A is a previously set distance or less from among parking frames recorded on the peripheral map  200 . The parking position determination unit  84  sets a position and an angle at which the own vehicle  1 A is to be parked within the selected parking frame, to determine a parking position P. 
     The parking path generation unit  85  generates a parking path R for parking the own vehicle  1 A at the parking position P determined by the parking position determination unit  84 . The parking path R is a path for moving the own vehicle  1 A to the parking position P from the position S 0  of the own vehicle  1 A. Known means is used to perform processing for generating the parking path. 
     The operation information generation unit  86  receives information about the parking path R generated by the parking path generation unit  85 . The operation information generation unit  86  generates operation information as information for causing the obstacle detection device  100  to control the traveling driving device  150  based on the received information about the parking path R. 
     The operation information generation unit  86  refers to the peripheral map  200  generated in the memory  70  by the map generation unit  83 , to acquire respective coordinates at the four vertexes of each of the range graphics  211 ,  213 , and  225  each representing the position and the range of the target object. 
     The operation information generation unit  86  outputs control information including path information as the information about the parking path R, range information as the information about the four vertexes of each of the range graphics  211 ,  213 , and  225 , and the generated operation information to the obstacle detection device  100 . 
     The obstacle detection device  100  is a computer device including the input/output I/F  110  (CAN transceiver, transceiver, Ethernet PHY), the memory  120 , and the processor  130  (second processor). The obstacle detection device  100  may be configured to include a storage device such as an HDD or an SSD, for example, in addition to the devices. 
     The input/output I/F  110  is connected to the communication bus  5 , and performs data communication with an external device connected to the communication bus  5 . The external device includes the position detection unit  10 , the sonar unit  30  and the path generation device  50 , and the traveling driving device  150 . 
     The memory  120  includes a ROM (read only memory) and a RAM (random access memory). The memory  120  may include a nonvolatile semiconductor memory such as a flash memory. The memory  120  stores a computer program to be executed by the processor  130 , data to be processed when the processor  130  executes the computer program, and data representing a processing result. The memory  120  stores sensor data outputted by the sonar unit  30  and control information received from the path generation device  50 . 
     The processor  80  includes a CPU and an MPU. 
     The obstacle detection device  100  includes an acquisition unit  131 , an operation control unit  132 , an inside/outside determination unit  133 , and an obstacle determination unit  134 , respectively, as functional components. Each of the functional components is a function to be implemented when the processor  80  performs an operation according to the computer program. 
     The acquisition unit  131  acquires range information and sensor data included in the control information stored in the memory  120 . The acquisition unit  131  outputs the acquired range information and sensor data to the inside/outside determination unit  133 . 
     The acquisition unit  131  outputs operation information stored in the memory  120  to the operation control unit  132 . 
     Further, the acquisition unit  131  acquires path information stored in the memory  120 . The acquisition unit  131  outputs the acquired path information to the obstacle determination unit  134 . 
     The operation control unit  132  generates, when receiving the operation information from the acquisition unit  131 , driving information for driving each of the units in the traveling driving device  150  according to the received operation information. The operation control unit  132  outputs the generated driving information to the traveling driving device  150 . 
     Here, the traveling driving device  150  will be described. 
     The traveling driving device  150  includes a steering device  151 , a driving device  153 , a braking device  155 , and a transmission device  157 . 
     The steering device  151  is a device including an actuator that steers a steering wheel of the own vehicle  1 A. The operation control unit  132  drives the actuator based on the driving information, and steers the steering wheel. 
     The driving device  153  is a device including an actuator that adjusts a driving force of a driving wheel of the own vehicle  1 A. When a power source of the own vehicle  1 A is an engine, a throttle actuator corresponds to the actuator. When the power source is a motor, the motor corresponds to the actuator. The operation control unit  132  drives the actuator based on the driving information, and adjusts the driving force of the driving wheel of the own vehicle  1 A. 
     The braking device  155  is a device including an actuator that drives a brake system provided in the own vehicle  1 A and applies a braking force to the wheel of the own vehicle  1 A. 
     The operation control unit  132  drives the actuator based on the driving information, and controls the braking force to be applied to the wheel of the own vehicle  1 A. 
     The transmission device  157  is a device including a transmission and an actuator. 
     The operation control unit  132  drives the actuator based on the driving information, and switches a speed change ratio of the transmission and forward traveling and reverse traveling of the own vehicle  1 A. 
     The inside/outside determination unit  133  receives the range information from the acquisition unit  131 . The inside/outside determination unit  133  loads a range graphic representing a position and a range of a target object represented by the received range information into the memory  120 , to generate an obstacle map  300 . An example of the obstacle map  300  is illustrated in  FIGS. 5 to 7 . 
     The inside/outside determination unit  133  acquires, when receiving the sensor data from the acquisition unit  131 , information about the target object included in the received sensor data. That is, the inside/outside determination unit  133  acquires information about a distance to the target object represented by the sensor data received from the sonar unit  30  and an orientation of the target object based on the own vehicle  1 A. The inside/outside determination unit  133  determines whether the target object is positioned inside or outside the range graphics  211 ,  213 , and  225  illustrated on the obstacle map  300  based on the information about the distance to the acquired target object and the orientation, for example. 
       FIG. 5  is diagram illustrating an example of the obstacle map  300  generated by the inside/outside determination unit  133 . 
     On the obstacle map  300 , a coordinate system having a position S 0  of an own vehicle  1 A as an origin and having an x-axis and a y-axis as two axes perpendicular to each other is also set. 
     A point U illustrated in  FIG. 5  represents a position of a target object detected by sensor data. It is assumed that coordinates of the point U are (xu, yu). 
     The inside/outside determination unit  133  first selects one of target range graphics. A case where a range graphic  211  has been selected will be described. The inside/outside determination unit  133  selects two adjacent vertexes among four vertexes of the range graphic  211 . In  FIG. 5 , a state where a point A and a point B have been respectively selected as the two adjacent vertexes. 
     The point A is positioned upstream when the vertex of the range graphic  211  is selected clockwise, and the point B is positioned downstream when the vertex of the range graphic  211  is selected clockwise. The inside/outside determination unit  133  generates a vector AB having the point A positioned upstream as a starting point and having the point B positioned downstream as a final point and a vector AU having the point A as a starting point and the point U as a final point. A component of the vector AB is (xb-xa, yb-ya), and a component of the vector AU is (xu-xa, yu-ya). 
     Then, the inside/outside determination unit  133  calculates an outer product AB×AU of the vector AB and the vector AU. 
       Vector  AB ×Vector  AU ={( xb−xa )·( yu−ya )}−{( xu−xa )·( yb−xa )}
 
     At this time, the inside/outside determination unit  133  generates a formula of the outer product such that the vector (e.g., the vector AB) connecting the two vertexes of the range graphic  211  precedes the vector (e.g., the vector AU) connecting the one vertex of the range graphic  211  and coordinates of the target object. 
     The inside/outside determination unit  133  also calculates an outer product of the other two adjacent vertexes of the range graphic  211  and the point U of the target object in addition to the outer product of the vector AB and the vector AU. Specifically, the inside/outside determination unit  133  calculates an outer product of a vector BD and a vector BU (the vector BD×the vector BU), an outer product of a vector DC and a vector DU (the vector DC×the vector DU), and an outer product of a vector CA and a vector CU (the vector CA×the vector CU). 
     The inside/outside determination unit  133  determines that the point U of the target object is positioned outside the range graphic  211  when calculation results of the outer products include even one positive value. The inside/outside determination unit  133  determines that the point U is positioned inside the range graphic  211  when the calculation results of the outer products are all negative values. 
     The inside/outside determination unit  133  determines, for all the other range graphics  213  and  225  represented by the range information, whether the point U of the target object is positioned inside or outside the range graphics  213  and  225 . The inside/outside determination unit  133  determines that the point U of the target object as an obstacle determination target when determining that the point U of the target object is positioned outside all the range graphics  211 ,  213 , and  225 . The inside/outside determination unit  133  determines that the point U of the target object is not the obstacle determination target when determining that the point U of the target object is positioned inside any one of the range graphics  211 ,  213 , and  225 . For example, if the point U of the target object is a point in the range graphic  211 , the point U of the target object is determined as a point at which the other vehicle  1 B has been detected. The path generation device  50  generates a parking path R in consideration of a position of the other vehicle  1 B. Thus, when the point U of the target object is a point in the range graphic  211 , even if the own vehicle  1 A is traveled along the parking path R, the own vehicle  1 A does not contact or collie with the target object. The inside/outside determination unit  133  excludes the point U of the target object from the obstacle determination target when determining that the point U of the target object is positioned inside any one of the range graphics  211 ,  213 , and  225 . The inside/outside determination unit  133  outputs coordinates of the point U of the target object that has been determined as the obstacle determination target to the obstacle determination unit  134 . 
       FIGS. 6 and 7  are diagrams each illustrating an obstacle map  300 . 
     The obstacle determination unit  134  receives coordinates of a point U of a target object that has been determined to be positioned outside all range graphics  211 ,  213 , and  225  by the inside/outside determination unit  133 , path information acquired by the acquisition unit  131 , and position and orientation information. 
     The obstacle determination unit  134  determines whether or not the point U of the target object the coordinates of which have been received is an obstacle to the own vehicle  1 A traveling in a parking path R. The obstacle determination unit  134  determines the target object that has been determined to contact or collide with the own vehicle  1 A traveling in the parking path as an obstacle. 
     The obstacle determination unit  134  first sets a plurality of determination points W on the parking path R represented by the path information. For example, the obstacle determination unit  134  sets the determination point W for each previously set distance.  FIG. 6  illustrates a state where the parking path R includes a path R 1  and a path R 2  and five determination points W 1 , W 2 , W 3 , W 4 , and W 5  are set in the path R 1  and the path R 2 . 
     The obstacle determination unit  134  operates an orientation when the own vehicle  1 A traveling along the parking path R has moved to the determination point W when a distance between the own vehicle  1 A and the determination point W is a predetermined distance or less and operates a range occupied by the own vehicle  1 A when the own vehicle  1 A is positioned at the determination point W. The obstacle determination unit  134  loads an own vehicle graphic  310  representing the operated range of the own vehicle  1 A into the obstacle map  300 .  FIG. 7  illustrates the own vehicle graphic  310  when the own vehicle  1 A is positioned at the determination point W 3 . 
     The obstacle determination unit  134  calculates a distance between coordinates of the point U of the target object received from the inside/outside determination unit  133  and the own vehicle graphic  310 , and determines whether or not the own vehicle  1 A contacts or collides with the target object. 
     The obstacle determination unit  134  determines, when the distance between the own vehicle graphic  310  and the coordinates of the point U of the target object is a previously set distance or less, that the target object is an obstacle. The obstacle determination unit  134  instructs the operation control unit  132  to stop traveling the own vehicle  1 A when determining that the target object is an obstacle. 
     The operation control unit  132  stops traveling the own vehicle  1 A when receiving the coordinates of the target object that has been determined as an obstacle by the obstacle determination unit  134 . The operation control unit  132  notifies the path generation device  50  that the traveling of the own vehicle  1 A is stopped, and causes the path generation device  50  to generate a parking path capable of avoiding contact or collision with the obstacle again. 
       FIGS. 8 and 9  are flowcharts each illustrating an operation of the obstacle detection device  100 . 
     The operation of the obstacle detection device  100  will be described with reference to the flowcharts of  FIGS. 8 and 9 . 
     First, the obstacle detection device  100  determines whether or not control information has been acquired from the path generation device  50  (step S 1 ). The path generation device  50  generates path information, range information, and operation information, and outputs the generated information to the obstacle detection device  100  as control information. The obstacle detection device  100  temporarily stores the received control information to the memory  120 . The obstacle detection device  100  reads out the control information from the memory  120 , to determine that the control information has been acquired. Step S 1  corresponds to an acquisition step. 
     The obstacle detection device  100  generates, when acquiring the control information (YES in step S 1 ), the obstacle map  300  in the memory  120  based on the range information included in the control information (step S 2 ). The obstacle detection device  100  records a range graphic representing a position and a range represented by the range information on the obstacle map  300 , to generate the obstacle map  300 . 
     Then, the obstacle detection device  100  generates a driving signal that operates each of the units in the traveling driving device  150  according to the operation information included in the control information. The operation control unit  132  outputs the generated driving signal to the traveling driving device  150 , to start traveling of the own vehicle  1 A (step S 3 ). As a result, an own vehicle  1 A starts to travel to a parking position P according to a parking path generated by the path generation device  50 . Step S 3  corresponds to an output step. 
     Then, the obstacle detection device  100  acquires sensor data representing a detection result of the sonar unit  30  from the memory  120  (step S 4 ). The obstacle detection device  100  determines whether or not information about a target object is included in the acquired sensor data (step S 5 ). The obstacle detection device  100  acquires information about a distance to the target object and an orientation of the target object based on the own vehicle  1 A. 
     If the obstacle detection device  100  cannot acquire the information about the target object from the sensor data (NO in step S 5 ), the obstacle detection device  100  acquires position and orientation information from the position acquisition unit  81 , and determines whether or not the own vehicle  1 A has reached the parking position P based on the acquired position and orientation information (step S 12 ). 
     If the obstacle detection device  100  determines that the own vehicle  1 A has reached the parking position P (YES in step S 12 ), the processing flow ends. If the obstacle detection device  100  determines that the own vehicle  1 A has not reached the parking position P (NO in step S 12 ), the obstacle detection device  100  acquires the sensor data again (step S 4 ), and determines whether or not the target object has been detected. 
     If the target object has been detected in determination in step S 5  (YES in step S 5 ), the obstacle detection device  100  performs inside/outside determination processing for determining whether the detected target object is positioned inside or outside a range graphic (step S 6 ). Details of the inside/outside determination processing will be described with reference to a flowchart of  FIG. 9 . Step S 6  corresponds to an inside/outside determination step. 
     If the target object that has been determined to be positioned outside the range graphic does not exist as a result of the inside/outside determination processing (NO in step S 7 ), the processing flow returns to step S 4 . In step S 4 , the obstacle detection device  100  acquires sensor data. If the target object that has been determined to be positioned outside the range graphic exists (YES in step S 7 ), the obstacle detection device  100  performs obstacle determination processing for determining whether or not the detected target object is an obstacle that contacts or collides with the own vehicle  1 A traveling along the parking path (step S 9 ). Step S 9  corresponds to an obstacle determination step. 
     The obstacle detection device  100  sets a plurality of determination points W on the parking path, and calculates an orientation of the own vehicle  1 A at the set determination point W based on the position and orientation information received from the position acquisition unit  81 . The obstacle detection device  100  generates an own vehicle graphic representing a range of the own vehicle  1 A when the own vehicle  1 A is positioned at the calculated determination point W based on the calculated orientation of the own vehicle  1 A at the determination point W. The obstacle detection device  100  determines whether or not a distance between the generated own vehicle graphic and the detected target object is a previously set distance or less (step S 10 ). If the distance between the own vehicle graphic and the target object is the previously set distance or less (YES in step S 10 ), the obstacle detection device  100  stops driving the driving device  153 , drives the braking device  155 , and stops traveling the own vehicle  1 A (step S 11 ). If the distance between the own vehicle graphic and the target object is not the previously set distance or less (NO in step S 10 ), the obstacle detection device  100  shifts to determination in step S 12 . 
     Then, details of the inside/outside determination processing in step S 6  will be described with reference to the flowchart of  FIG. 9 . 
     First, the obstacle detection device  100  selects one of range graphics (step S 61 ). Then, the obstacle detection device  100  selects clockwise two adjacent vertexes among vertexes of the selected range graphic (step S 62 ). The selected two vertexes are set as A and B, and a point of a target object is set as a point U. It is assumed that the point A is positioned upstream and the point B is positioned downstream when the two adjacent vertexes of the range graphic are selected clockwise. Then, the obstacle detection device  100  generates a vector AB connecting coordinates of the target object and the selected two vertexes and a vector AU connecting the upstream vertex A and the point U of the target object, and calculates an outer product AB×AU of the generated vectors (step S 63 ). Then, the obstacle detection device  100  determines whether or not there is an unselected combination of the two adjacent vertexes of the range graphic that has been selected in step S 61  (step S 64 ). 
     If the unselected combination of the two adjacent vertexes exists (YES in step S 64 ), the processing flow returns to step S 62 . In step S 62 , the obstacle detection device  100  selects the two adjacent vertexes. If the unselected combination of the two adjacent vertexes does not exist (NO in step S 64 ), the obstacle detection device  100  determines whether or not values of outer products respectively calculated for combinations of the two adjacent vertexes are all negative values (step S 65 ). If the values of the outer products are not all negative values, that is, the values of the outer products include a positive value (NO in step S 65 ), the obstacle detection device  100  determines that the position of the target object is outside the range graphic (step S 67 ). If the values of the outer products are all negative values (YES in step S 65 ), the obstacle detection device  100  determines that the position of the target object is inside the range graphic (step S 66 ). 
     Then, the obstacle detection device  100  determines whether or not all the range graphics have been each selected as a target (step S 68 ). If all the range graphics have not been each selected as a target (NO in step S 68 ), the processing flow returns to step S 61 . In step S 61 , the obstacle detection device  100  selects one of the range graphics that have not been selected (step S 61 ). If all the range graphics have been each selected as a target (YES in step S 68 ), the obstacle detection device  100  determines whether or not the range graphic inside which the target object has been determined to be positioned exists (step S 69 ). 
     If the range graphic inside which the target object has been determined to be positioned does not exist (NO in step S 69 ), the obstacle detection device  100  determines that the target object is positioned outside all the range graphics (step S 70 ). The obstacle detection device  100  determines that the target object is an obstacle determination target, and outputs coordinates of the target object. 
     If the range graphic inside which the target object has been determined to be positioned exists (YES in step S 69 ), the obstacle detection device  100  determines that the target object is positioned inside the range graphic, and determines whether or not there is another target object that has not been processed (step S 71 ). If the obstacle detection device  100  determines that the other target object that has not been processed exists (YES in step S 71 ), the processing flow returns to step S 61 . If the obstacle detection device  100  determines that the other target object that has not been processed does not exist (NO in step S 71 ), the processing flow proceeds to step S 7 . 
     As described above, the obstacle detection device  100  according to the present embodiment includes the input/output I/F  110 , the acquisition unit  131 , the operation control unit  132 , the inside/outside determination unit  133 , and the obstacle determination unit  134 . 
     The acquisition unit  131  acquires path information as information about the parking path R to the parking position P where the own vehicle  1 A is to be parked and range information representing a position and a range of a target object existing around the own vehicle  1 A. 
     The operation control unit  132  generates a driving signal, for operating the traveling driving device  150  that travels the own vehicle  1 A, according to the path information acquired by the acquisition unit  131 , and outputs the generated driving signal to the traveling driving device  150 . 
     The inside/outside determination unit  133  determines, when receiving surroundings information representing a situation around the own vehicle  1 A from the path generation device  50  via the input/output I/F  110 , whether the target object included in the received surroundings information is a target object positioned inside the range represented by the acquired range information or a target object positioned outside the range. That is, the inside/outside determination unit  133  determines whether a target object represented by sensor data received from the sonar unit  30  is the target object positioned inside the range represented by the range information or the target object positioned outside the range. 
     The obstacle determination unit  134  determines whether or not the target object that has been determined to be positioned outside the range by the inside/outside determination unit  133  is an obstacle to the own vehicle  1 A traveling in the parking path R. 
     Therefore, the obstacle detection device  100  performs obstacle determination for the target object positioned outside the range represented by the range information, thereby making it possible to shorten a time period required to detect the obstacle that obstructs the own vehicle  1 A and improve a detection accuracy of the obstacle that obstructs the own vehicle  1 A. 
     The obstacle detection device  100  does not determine whether or not the target object that has been determined to be positioned inside the range by the inside/outside determination unit  133  is an obstacle to the own vehicle  1 A traveling in the parking path R. 
     Therefore, the obstacle detection device  100  can shorten a time period required to detect the obstacle that obstructs the own vehicle  1 A. 
     The inside/outside determination unit  133  calculates an outer product of a vector connecting respective coordinates of two adjacent vertexes of the range represented by the range information and a vector connecting respective coordinates of either one of the two vertexes and the target object, and determines whether the target object is positioned inside or outside the range represented by the range information based on a calculation result of the outer product. 
     Therefore, a determination accuracy for determining whether the obstacle is positioned inside or outside the range represented by the range information can be improved. 
     The obstacle determination unit  134  sets a plurality of determination points W on the parking path R, and generates an own vehicle graphic  310  representing a range occupied by the own vehicle  1 A when the own vehicle  1 A is positioned at each of the determination points W. 
     The obstacle determination unit  134  determines a target object spaced apart from the own vehicle graphic  310  by a previously set distance or less as an obstacle, and instructs the operation control unit  132  to stop traveling the own vehicle  1 A when the target object that has been determined as the obstacle has been detected. 
     Therefore, when an obstacle that obstructs the own vehicle  1 A traveling in the parking path has been detected, the traveling of the own vehicle  1 A can be stopped. 
     The above-described embodiment is merely an illustration of one aspect of the present invention, and variations and applications are optionally possible without departing from the scope and spirit of the invention. 
     For example, the path generation device  50  and the obstacle detection device  100  may be respectively composed of separate computer devices, as illustrated in  FIG. 1 , or may be composed of one computer device, as illustrated in  FIG. 10 .  FIG. 10  illustrates a configuration in which an obstacle detection device  500  includes a position acquisition unit  531 , a situation acquisition unit  532 , an acquisition unit  540 , an operation information generation unit  533 , an operation control unit  534 , an inside/outside determination unit  535 , and an obstacle determination unit  536 . The acquisition unit  540  includes a map generation unit  541 , a parking position determination unit  542 , and a parking path generation unit  543 . That is, the obstacle detection device  500  illustrated in  FIG. 10  generates path information as information about a parking path to a parking position P and range information representing a position and a range of an object existing around an own vehicle  1 A. 
     Although a case where a parking mode of the own vehicle  1 A is a parallel parking is illustrated in  FIGS. 2 to 7 , the parking mode of the own vehicle  1 A may be perpendicular parking or angle parking. The parallel parking is a parking manner for parking the own vehicle  1 A such that the own vehicle  1 A and another vehicle are arranged in a vehicle length direction of the own vehicle  1 A. The angle parking is a parking manner for parking the own vehicle  1 A in a parking stall provided diagonally to a path in front of or behind the parking stall. 
     Although  FIGS. 2 to 7  illustrate a case where the range graphics  211 ,  213 , and  225  representing the range of the target object each have a rectangular shape, the range graphics  211 ,  213 , and  225  may not each have a rectangular shape but may each have a polygonal shape such as a triangular shape or a pentagonal shape. 
     The inside/outside determination unit  133  selects the two adjacent vertexes of the range graphic clockwise, and therefore determines that the point U of the target object is positioned outside the range graphic if the values of the outer products include even one positive value and determines that the point U is positioned inside the range graphic if the calculation results of the outer products are all negative values. 
     In addition thereto, the two adjacent vertexes of the range graphic may be selected counterclockwise. In this case, the inside/outside determination unit  133  determines that the point U of the target object is positioned outside the range graphic if the values of the outer products include even one negative value, and determines that the point U of the target object is positioned inside the range graphic if the calculation results of the outer products are all positive values. 
     A block diagram illustrating respective configurations of the path generation device  50  and the obstacle detection device  100  illustrated in  FIG. 1  is a schematic view illustrated by classifying components depending on a main processing content to facilitate understanding of the present invention, and the components can also be classified into more components depending on a processing content. The components can also be classified such that one of the components performs more processes. 
     If an obstacle detection method according to the present invention is implemented using a computer, a program that the computer is caused to execute can also be configured in a form of a recording medium or a transmission medium that transmits the program. A magnetic or optical recording medium or a semiconductor memory device can be used for the recording medium. Specific examples include portable or fixed recording media such as a flexible disk, an HDD, a CD-ROM (compact disk read only memory), a DVD, a Blue-ray (registered trademark) Disc, a magnetooptical disk, a flash memory, and a card-type recording medium. The above-described recording medium may be a nonvolatile storage device such as a ROM or an HDD included in the path generation device  50 . 
     Processing units in the flowchart illustrated in each of  FIGS. 8 and 9  are obtained by dividing the processing units of the flowchart depending on a main processing content to facilitate understanding of the processing of the obstacle detection device  100 . The present invention is not limited depending on a method of dividing the process of the obstacle detection device  100  and the name of the divided process. The processing of the obstacle detection device  100  may be divided into more processing units depending on the processing content. The processing of the obstacle detection device  100  may be divided such that one of the processing units includes more processes. 
     REFERENCE SIGNS LIST 
     
         
           1 A Vehicle 
           1 B Another vehicle 
           1 C Another vehicle 
           3  In-vehicle apparatus 
           5  Communication bus 
           10  Position detection unit 
           30  Sonar unit 
           50  Path generation device 
           60  Input/output I/F (input interface) 
           70  Memory 
           80  Processor 
           81  Position acquisition unit 
           82  Situation acquisition unit 
           83  Map generation unit 
           84  Parking position determination unit 
           85  Parking path generation unit 
           86  Operation Information generation unit 
           100  Obstacle detection device 
           110  Input/output I/F 
           120  Memory 
           130  Processor 
           131  Acquisition unit 
           132  Operation control unit 
           133  Inside/outside determination unit 
           134  Obstacle determination unit 
           150  Traveling driving device (traveling driving unit) 
           151  Steering device 
           153  Driving device 
           155  Braking device 
           157  Transmission device 
           200  Peripheral map 
           201 ,  202 ,  203  Parking region 
           220  Wall 
           300  Obstacle map 
           310  Own vehicle graphic