JP2005331352A - Positioning system and positioning method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enhance positioning accuracy between a vehicle mounted with a radar device and a target, and to make positioning work more efficient. <P>SOLUTION: This positioning system A performs relative positioning between the vehicle 100 and the target 1 with an incident surface 1a entered by a beam from the radar device 101 in adjusting a beam axis of the radar device 101 mounted on the vehicle 100. The vehicle 100 is photographed by a camera 11 with its photographing direction set in a direction perpendicular to the incident surface 1a. The direction of the vehicle 100 relative to the incidence surface 1a is determined based on an image obtained by the photographing. Based on a determination result, the target 1 is moved so that the normal direction of the beam axis makes a right angle with the incident surface 1a. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for adjusting a beam axis of a radar apparatus mounted on a vehicle.

  In order to realize an auto-cruise function and a function for predicting a collision with an obstacle, it is becoming popular to provide a radar device in a vehicle. Generally, a radar device is disposed in front of a vehicle, transmits a beam to the front of the vehicle, and receives a reflected wave thereof to detect an obstacle in front of the vehicle and measure a distance from the obstacle. Here, unless the beam transmitted from the radar device is directed in the designed direction (hereinafter referred to as a normal direction), the accuracy of obstacle detection or the like is affected. For this reason, when attaching the radar device to the vehicle, it is checked whether the beam axis of the beam transmitted from the radar device is in the normal direction, and if there is a deviation, the attachment position of the radar device is adjusted. For example, an operation for adjusting the beam axis is performed.

  Various methods for adjusting the beam axis have been proposed. For example, a beam is transmitted from a radar device to a target that is virtually assumed as an obstacle, and a deviation of the beam axis is detected by receiving the reflected wave. A method has been proposed (for example, Patent Document 1). In addition, a method has been proposed in which a target is constituted by an electric field strength measuring device, and a beam axis deviation is detected by measuring the electric field strength of a beam transmitted from a radar device.

JP-A-11-337634

  Here, as a premise for adjusting the beam axis, the vehicle on which the radar apparatus is mounted and the target need to be relatively appropriately positioned. In other words, if the beam entrance surface of the target is not perpendicular to the normal direction of the beam axis of the vehicle, the beam axis is normal even if the beam axis adjustment work according to the conventional example described above is performed. There is a fear that the deviation remains in the direction. Conventionally, the positioning of the vehicle and the target is performed by the operator's sense, and the positioning accuracy is not always good, and the efficiency of the work is not achieved.

  Accordingly, an object of the present invention is to improve the positioning accuracy between a vehicle on which a radar device is mounted and a target, and to improve the efficiency of positioning work.

  According to the present invention, in adjusting the beam axis of the radar device mounted on the vehicle, the positioning system performs relative positioning between the vehicle and the target having the incident surface on which the beam from the radar device is incident. The photographing direction is set to a direction orthogonal to the incident surface, and the direction of the vehicle relative to the incident surface is determined based on the photographing means for photographing the vehicle and the image photographed by the photographing means. A positioning system comprising: a determining unit; and a moving unit that moves the target so that a normal direction of the beam axis and the incident surface are orthogonal to each other based on a determination result of the determining unit. Is provided.

  In this system, a vehicle is photographed in a direction orthogonal to the incident surface, and the orientation of the vehicle with respect to the incident surface is determined based on the photographed image. Then, based on the determination result of the direction of the vehicle, the target is moved so that the normal direction of the beam axis is orthogonal to the incident surface of the target. By photographing the vehicle in a direction perpendicular to the incident surface, the orientation of the vehicle relative to the incident surface can be determined from the image, and the target can be aligned by moving the target based on the determination result. Positioning accuracy can be improved and variation in positioning accuracy can be suppressed as compared with the case where it depends on the operator's sense. Furthermore, since positioning can be automated, the efficiency of positioning work can be improved.

  In the present invention, the photographing means may be attached to the target. According to this configuration, even if the target moves, it is possible to always maintain the photographing direction of the photographing unit in a direction orthogonal to the incident surface.

  Further, in the present invention, the normal direction is a center axis direction of the vehicle, the imaging unit captures an image of the front of the vehicle, and the determination unit includes the image of the front captured by the imaging unit. Of these, the orientation of the vehicle with respect to the incident surface can also be determined by determining the left-right symmetry of the image of the predetermined part of the vehicle. According to this configuration, it is possible to easily determine the orientation of the vehicle with respect to the incident surface by determining the left-right symmetry of the image of the predetermined part of the vehicle.

  In this case, examples of the predetermined portion include a pillar member of the vehicle. Since the pillar member is provided in any vehicle and is provided symmetrically, the orientation of the vehicle relative to the incident surface can be easily determined by using this as a reference for determination.

  Further, in the present invention, the moving means includes a rotating device that rotates the target to change the direction of the incident surface so that the normal direction and the incident surface are orthogonal to each other, and the normal direction is the And a moving device that moves the target on a predetermined trajectory so as to pass through the center of the incident surface. By rotating the target and changing the direction of the incident surface, it is possible to easily position the vehicle and the target, and by moving the target on a predetermined trajectory, the normal direction of the beam axis and the incident surface Even when the center position is shifted, the alignment can be easily performed.

Further, according to the present invention, when adjusting the beam axis of the radar device mounted on the vehicle, the vehicle and the target having the incident surface on which the beam from the radar device is incident are relatively positioned. A positioning method, wherein a shooting direction is set to a direction orthogonal to the incident surface, and a shooting step of shooting the vehicle, and an orientation of the vehicle with respect to the incident surface based on an image shot by the shooting step. A determining step of determining, and a moving step of moving the target so that the normal direction of the beam axis and the incident surface are orthogonal to each other based on the determination result of the determining step;
A positioning method is provided.

  In this method, the vehicle is photographed in a direction orthogonal to the incident surface, and the orientation of the vehicle with respect to the incident surface is determined based on the photographed image. Then, based on the determination result of the direction of the vehicle, the target is moved so that the normal direction of the beam axis is orthogonal to the incident surface of the target. By photographing the vehicle in a direction perpendicular to the incident surface, the orientation of the vehicle relative to the incident surface can be determined from the image, and the target can be aligned by moving the target based on the determination result. Positioning accuracy can be improved and variation in positioning accuracy can be suppressed as compared with the case where it depends on the operator's sense. Furthermore, since positioning can be automated, the efficiency of positioning work can be improved.

  As described above, according to the present invention, it is possible to improve the positioning accuracy between the vehicle on which the radar device is mounted and the target, and to increase the efficiency of the positioning operation.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1A is a side view of a positioning system A according to an embodiment of the present invention, and FIG. 1B is a plan view of the positioning system A. The positioning system A includes a camera 11 that captures an image of the vehicle 100 and a moving unit 12 that moves the target 1 on which the beam from the radar apparatus 101 is incident.

  The radar apparatus 101 is disposed in the front center portion (for example, a bumper portion) of the vehicle 100 and transmits a beam to the front of the vehicle 100 substantially horizontally. In the present embodiment, it is assumed that the normal direction of the beam axis of the radar apparatus 101 is the central axis direction of the vehicle 100. In the state shown in the figure, the radar apparatus 101 is still temporarily mounted on the vehicle 100 and is fixed to the vehicle 100 by beam axis adjustment work performed after positioning of the vehicle 100 and the target 1 to be described later. become.

  The target 1 has an incident surface 1a on which a beam from the radar apparatus 101 is incident. The type of the target 1 varies depending on the beam axis adjustment method. For example, an adjustment method for detecting a beam axis deviation by transmitting a beam from the radar apparatus 101 and receiving the reflected wave by the radar apparatus 101 is adopted. In this case, the incident surface 1a constitutes a beam reflecting surface. In addition, when the target 1 is composed of an electric field intensity measuring device and an adjustment method for detecting the beam axis deviation by measuring the electric field intensity of the beam transmitted from the radar apparatus 101 is used, the incident surface 1a has an electric field intensity measurement. This constitutes the beam entrance surface of the apparatus. In any adjustment method, the incident surface 1a is a surface to which a beam transmitted from the radar apparatus 101 is irradiated. The target 1 is located at a predetermined distance from the vehicle 100 in front of the vehicle 100. The height of the center position of the incident surface 1a is set to be substantially the same as that of the beam transmission unit of the radar apparatus 101.

  The camera 11 is a digital camera that photographs the vehicle 100 with the photographing direction set to a direction orthogonal to the incident surface 1a. By setting the photographing direction to a direction orthogonal to the incident surface 1a, the image photographed by the camera 11 is an image of a part of the vehicle 100 that faces the incident surface 1a. In the case of this embodiment, the camera 11 is attached to the target 1. A configuration in which the camera 11 is not attached to the target 1 can also be adopted, but once the camera 11 is attached to the target 1 and the shooting direction is set to a direction orthogonal to the incident surface 1a, the shooting direction is always set even if the target 1 is moved. Can maintain the state orthogonal to the incident surface 1a, and the operation of resetting the photographing direction for each movement of the target 1 becomes unnecessary.

  In the case of this embodiment, the shooting direction of the camera 11 is matched with the direction orthogonal to the center of the incident surface 1a. That is, the camera 11 is attached above the center of the incident surface 1a. By doing so, the center of the image photographed by the camera 11 substantially coincides with the center of the incident surface 1a. Here, in the present embodiment, it is assumed that the normal direction of the beam axis of the radar apparatus 101 is the central axis direction of the vehicle 100 as described above. Therefore, if the vehicle 100 and the target 1 are relatively positioned so that the central axis direction of the vehicle 100 is orthogonal to the incident surface 1a, the normal direction of the beam axis is orthogonal to the incident surface 1a. That is, the front surface of the vehicle 100 only needs to face the entrance surface 1a. In the present embodiment, as will be described later, an image of the front of the vehicle 100 is taken by the camera 11 in order to determine whether or not the front of the vehicle 100 faces the entrance surface 1a.

  The moving unit 12 is a unit that moves the target 1 when positioning the vehicle 100 and the target 1. In the case of the present embodiment, the moving unit 12 rotates the target 1, and the moving unit 12 moves on a predetermined track by being guided by a rail 13 installed on the floor of the work place. The rail 13 is laid in a straight line in the vehicle width direction of the vehicle 100, and the moving unit 12 moves linearly in parallel on the horizontal plane. FIG. 2A is a configuration diagram showing an outline of the moving unit 12.

  The moving unit 12 includes a rotating device that rotates the target 1 to change the direction of the incident surface 1a so that the normal direction of the beam axis and the incident surface 1a are orthogonal to each other. In the case of this embodiment, this rotating device includes a motor 121, a pulley 121a attached to the output shaft of the motor 121, and a pulley 1c attached to the pulley 121a and the rotating shaft 1b protruding downward from the target 1. And a belt 121b stretched between the two. Thus, by rotating the motor 121 forward and backward, the driving force is transmitted to the rotating shaft 1b via the belt 121b, and the target 1 rotates around the vertical axis, that is, on the horizontal plane. For example, a stepping motor can be used as the motor 121, and any motor can be used as long as the amount of rotation can be controlled. In the present embodiment, the target 1 is rotated by the belt transmission mechanism, but other drive types such as a gear mechanism may be used.

  Next, the moving unit 12 includes a moving device that moves the target 1 on the track defined by the rail 13 so that the normal direction of the beam axis passes through the center of the incident surface 1a. In the case of this embodiment, the moving device includes a motor 122, a pulley 122a attached to the output shaft of the motor 122, and a belt 122b stretched between the pulley 122a and the pulley 123a attached to the rotating shaft 123. And comprising. A wheel 124 having an H-shaped cross section that rolls on the rail 13 is attached to the rotating shaft 123. Thus, by rotating the motor 122 forward and backward, the driving force is transmitted to the rotating shaft 123 via the belt 122b, the wheel 124 rotates, and the moving unit 12 travels on the rail 13. For example, a stepping motor can be used as the motor 122, and any motor can be used as long as the amount of rotation can be controlled. In the present embodiment, the wheel 124 is rotated by the belt transmission mechanism, but other drive types such as a gear mechanism may be used.

  Next, the control circuit of the positioning system A will be described. FIG. 2B is a block diagram of a control circuit of the positioning system A. The control circuit of the positioning system A may be attached to the moving unit 12 or provided outside. A personal computer may also be used. The control circuit includes a CPU 51 that controls the entire system and particularly executes a positioning process described later. The CPU 51 is connected to the camera 11 via the interface 54, issues a shooting instruction to the camera 11, and acquires image data shot by the camera 11. The CPU 51 is also connected to the motor drive circuits 56a and 56b via the interface 55. The motor 122 and the motor 121 are connected to the motor drive circuits 56a and 56b, respectively. The CPU 51 outputs a drive command to the motor drive circuits 56a and 56b via the interface 55, whereby the motor 122 and the motor 121 are output. Rotation control is performed. The RAM 52 stores variable data and functions as a work area for the CPU 51. The ROM 53 stores fixed data, and particularly stores a positioning processing program to be described later. The RAM 52 and ROM 53 are not necessarily limited to these, and other storage means may be employed.

  Next, an example of positioning processing by the positioning system A having such a configuration will be described. Here, it is assumed that the positional relationship between the vehicle 100 and the target 1 is in the state shown in FIG. In the example of the figure, the normal direction of the beam axis (in the present embodiment, the direction of the central axis of the vehicle 100) is not orthogonal to the incident surface 1a of the target 1 and is greatly deviated. FIG. 3 is a flowchart of positioning processing by the positioning system A, which is executed by the CPU 51.

  In S <b> 1, an image of the front of the vehicle 100 is taken by the camera 11. FIG. 4B is a diagram illustrating an example of a captured image of the vehicle 100 assuming that the positional relationship between the vehicle 100 and the target 1 is in the state of FIG. As shown in the figure, it can be seen that the vehicle 100 is shown with a large inclination even though it is an image of the front of the vehicle 100. In S2, a process of determining the orientation of the vehicle 100 with respect to the incident surface 1a is performed based on the image photographed in S1. Based on the determination result, the target 1 is moved (turned) so that the normal direction of the beam axis and the incident surface 1a are orthogonal to each other as will be described later.

  Here, various methods can be adopted as a method for determining the orientation of the vehicle 100 based on the image photographed in S1, but in the case of the present embodiment, the front surface of the vehicle 100 faces the entrance surface 1a as described above. In this case, the normal direction of the beam axis is perpendicular to the incident surface 1a. That is, it is only necessary that the image captured in S <b> 1 is a complete front view image of the vehicle 100. In general, a vehicle is designed symmetrically, and when the vehicle 100 is viewed from the front, there is at least a portion that is symmetrical. And if the site | part is left-right symmetrical on the image image | photographed with the camera 11, the front of the vehicle 100 will face the entrance plane 1a. Therefore, in the present embodiment, the orientation of the vehicle 100 is determined by determining the left-right symmetry of the left and right pillar members (so-called A pillars) of the vehicle 100 in the image captured by the camera 11.

  4B will be described. First, as shown in FIG. 7A, images 102a and 102b of the left and right pillar members of the vehicle 100 are extracted by a known image processing technique. Then, as shown in FIG. 7B, a vertical center line Z is set between the extracted pillar member images 102a and 102b, and one image (image 102a in the figure) is set with respect to the center line Z. A symmetrical figure 102a 'is created and superimposed on the image 102b. If the figure 102a 'and the image 102b are exactly overlapped, the image of the vehicle 100 captured by the camera 11 is a bilaterally symmetric image, and the front of the vehicle 100 faces the entrance surface 1a. On the other hand, when both are shifted and overlapped, the front surface of the vehicle 100 does not face the entrance surface 1a. In the example of FIG. 7B, since the figure 102a 'and the image 102b are shifted and overlapped, it is determined that the front surface of the vehicle 100 does not face the entrance surface 1a. In the present embodiment, the orientation of the vehicle 100 with respect to the incident surface 1a can be determined in this way.

  In order to improve the accuracy of image extraction of the left and right pillar members of the vehicle 100, the pillar members of the vehicle 100 may be previously provided with alignment marks. Further, the symmetry determination target is not limited to the pillar member, and may be another part of the vehicle 100, for example, a body line. Further, an alignment mark may be provided on the vehicle 100 so as to be symmetric with respect to the center thereof, and the alignment mark may be extracted from the photographed image to determine the orientation of the vehicle 100.

  Returning to FIG. 3, in S3, as a result of the determination in S2, whether or not the normal direction of the beam axis is not perpendicular to the incident surface 1a and is shifted (ie, whether the front of the vehicle 100 faces the incident surface 1a) or not. judge. If not, the process proceeds to S4, and if not, the process proceeds to S5. In the example of FIGS. 4A and 4B, it is determined that there is a shift, and the process proceeds to S4. In S4, based on the determination result of S2, the target 1 is moved so that the normal direction of the beam axis and the incident surface 1a are orthogonal to each other. Here, a drive command is output to the motor drive circuit 56 b and the target 1 is rotated by the motor 121.

  The rotation amount of the target 1 may be a predetermined rotation amount, or may be calculated based on the determination result of S2. When the movement of the target 1 is completed, the process returns to S1 and the same processing is performed to check whether or not the direction of the incident surface 1a has changed so that the normal direction of the beam axis is orthogonal to the incident surface 1a. A series of processing is repeated until the normal direction is orthogonal to the incident surface 1a.

  FIG. 5A is a view showing a state in which the target 1 is rotated from the state of FIG. 4A so that the normal direction of the beam axis is orthogonal to the incident surface 1a, and FIG. Is a captured image of the camera 11 in the state of FIG. FIGS. 8A and 8B are explanatory diagrams when the orientation determination processing (S2) of the vehicle 100 is performed on the image of FIG. 5B. As shown in FIG. 100 left and right pillar member images 102a and 102b are extracted. As shown in FIG. 8B, a vertical center line Z is set between the extracted pillar member images 102a and 102b. In the figure, for the image 102a), a symmetric figure 102a 'with respect to the center line Z is created and superimposed on the image 102b.

  In the example of FIG. 8B, the figure 102a 'and the image 102b are superimposed almost exactly. Accordingly, in the state shown in FIG. 6A, in the process of S3 of FIG. 3, it is determined that the normal direction of the beam axis is orthogonal to the incident surface 1a, and the process proceeds to S5. In S5, the position of the vehicle 100 with respect to the incident surface 1a is determined based on the captured image of the vehicle 100. Specifically, it is determined whether or not the normal direction of the beam axis passes through the center of the incident surface 1a. As described above, in the present embodiment, the shooting direction of the camera 11 is set to a direction orthogonal to the center of the incident surface 1a. Therefore, if the image of the vehicle 100 is positioned at the approximate center of the captured image, the normal direction of the beam axis passes through the center of the incident surface 1a. Since the image of the vehicle 100 is shifted to the right in the photographed image of FIG. 5B, the normal direction of the beam axis does not pass through the center of the incident surface 1a in the state of FIG. .

  In S6, as a result of the determination in S5, it is determined whether the normal direction of the beam axis does not pass through the center of the incident surface 1a and is shifted. If it is shifted, the process proceeds to S7, and if not shifted, the process is terminated. In the case of the examples of FIGS. 5A and 5B, it is determined that there is a shift, and the process proceeds to S7. In S7, based on the determination result in S5, the target 1 is moved so that the normal direction of the beam axis passes through the center of the incident surface 1a. Here, a drive command is output to the motor drive circuit 56 a, and the target 1 is translated by the motor 122. The parallel movement amount of the target 1 may be a predetermined movement amount, or may be calculated based on the determination result of S5. When the movement of the target 1 is completed, the process proceeds to S8, and an image of the vehicle 100 is taken by the camera 11. Thereafter, the process returns to S5 and the same processing is performed to check whether or not the normal direction of the beam axis passes through the center of the incident surface 1a and continues until the normal direction of the beam axis passes through the center of the incident surface 1a. Repeat the process.

  FIG. 6A is a diagram showing a state in which the target 1 is translated from the state of FIG. 5A so that the normal direction of the beam axis passes through the center of the incident surface 1a. b) is a photographed image of the camera 11 in the state of FIG. In the photographed image of FIG. 6B, since the image of the vehicle 100 is located substantially at the center, it is determined that there is no deviation in the process of S6, and the process ends. As described above, the normal direction of the beam axis and the incident surface 1a are orthogonal to each other, and the normal direction of the beam axis passes through the center of the incident surface 1a, and the positioning of the vehicle 100 and the target 1 is completed. Thereafter, the beam axis is adjusted.

  Thus, in this embodiment, by photographing the vehicle 100 in a direction orthogonal to the incident surface 1a, the orientation of the vehicle 100 with respect to the incident surface 1a can be determined from the image, and the target 1 is moved based on the determination result. Since both can be aligned with each other, positioning accuracy can be improved and variation in positioning accuracy can be suppressed as compared with the conventional case where it depends on the operator's sense. Furthermore, since positioning can be automated, the efficiency of positioning work can be improved.

  Further, by determining the left-right symmetry of the image of the pillar member of the vehicle 100, the orientation of the vehicle 100 with respect to the incident surface 1a can be easily determined. Further, by rotating the target 1 and changing the direction of the incident surface 1a, the vehicle 100 and the target 1 can be easily positioned, and the target 1 is moved on the rail 13 to thereby move the beam. Even when the center position of the normal direction of the axis and the incident surface 1a is deviated, the alignment can be easily performed.

(A) is a side view of the positioning system A according to an embodiment of the present invention, and (b) is a plan view of the positioning system A. (A) is a block diagram of the moving unit 12, (b) is a block diagram of a control circuit of the positioning system A. 4 is a flowchart of positioning processing by a positioning system A. (A) is a figure which shows the example of the positional relationship of the vehicle 100 and the target 1, (b) is a figure which shows the picked-up image of the vehicle 100. FIG. (A) is operation | movement explanatory drawing in the case of moving the target 1, (b) is a figure which shows the picked-up image of the vehicle 100 after the movement of the target 1. FIG. (A) is operation | movement explanatory drawing in the case of moving the target 1, (b) is a figure which shows the picked-up image of the vehicle 100 after the movement of the target 1. FIG. (A) And (b) is explanatory drawing of the symmetry determination of the vehicle 100. FIG. (A) And (b) is explanatory drawing of the symmetry determination of the vehicle 100. FIG.

Explanation of symbols

A Positioning system 1 Target 1a Incident surface 11 Camera 12 Moving unit 13 Rail 100 Vehicle 101 Radar device

Claims (6)

In adjusting a beam axis of a radar device mounted on a vehicle, the positioning system performs relative positioning between the vehicle and a target having an incident surface on which a beam from the radar device is incident.
An imaging means for setting the imaging direction to a direction orthogonal to the incident surface, and imaging the vehicle;
A discriminating means for discriminating the orientation of the vehicle with respect to the incident surface based on an image photographed by the photographing means;
Based on the determination result of the determining means, moving means for moving the target so that the normal direction of the beam axis is orthogonal to the incident surface;
A positioning system comprising:   The positioning system according to claim 1, wherein the photographing unit is attached to the target. The normal direction is the central axis direction of the vehicle,
The imaging means captures an image of the front of the vehicle,
The discriminating unit discriminates the orientation of the vehicle with respect to the incident surface by discriminating the left-right symmetry of the image of the predetermined part of the vehicle among the front images photographed by the photographing unit. The positioning system according to claim 1 or 2, characterized in that   The positioning system according to claim 3, wherein the predetermined part is a pillar member of the vehicle. The moving means is
A rotating device that rotates the target to change the direction of the incident surface so that the normal direction and the incident surface are orthogonal to each other;
A moving device that moves the target on a predetermined trajectory so that the normal direction passes through the center of the incident surface;
The positioning system according to any one of claims 1 to 4, further comprising: In adjusting a beam axis of a radar device mounted on a vehicle, a positioning method for performing relative positioning between the vehicle and a target having an incident surface on which a beam from the radar device is incident,
An imaging process in which an imaging direction is set to a direction orthogonal to the incident surface, and the vehicle is imaged,
A determination step of determining an orientation of the vehicle with respect to the incident surface based on the image captured by the imaging step;
Based on the determination result of the determination step, a moving step of moving the target so that the normal direction of the beam axis and the incident surface are orthogonal to each other;
A positioning method comprising:

Images