JP2011017645A - Target acquisition tracking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a target acquisition tracking device capable of tracking a target efficiently by improving visual axis setting and flexibility of an object visual field when acquiring a three-dimensional shape of the target existing in the visual field of a two-dimensional image.SOLUTION: The device has a constitution wherein an infrared imaging unit having a sensor for acquiring two-dimensional image information is separated from a laser radar having a sensor for acquiring three-dimensional shape information, and can set respectively independently a visual axis and a visual field of the two-dimensional image information, and a direction and its scanning range for acquiring the three-dimensional image information. While the visual axis of the infrared imaging unit is allowed to agree with own moving direction, the visual axis of the laser radar is allowed to agree with a direction of the visual axis of the infrared imaging unit when acquiring the target, and the three-dimensional shape information is acquired by scanning uniaxially in an azimuth angle range of the visual field of the infrared imaging unit. Further, when tracking the target, the visual axis is set in the target direction, and the three-dimensional shape of the target is acquired by scanning uniaxially in a range restricted based thereon.

Description

  The present invention relates to a target acquisition and tracking device that acquires and tracks a target, and in particular, searches for and captures a target while acquiring two-dimensional and three-dimensional information on the ground from above using different sensors. The present invention relates to a target acquisition and tracking device for identifying and tracking.

  Conventionally, as a device that reliably identifies and tracks a target in the field of view at night or in poor visibility, for example, a remote that combines an infrared sensor as a passive sensor and a laser radar as an active sensor A sensing system has been devised. In a system using this type of light wave, a multi-spectrum sensor in which an infrared imaging sensor and a light receiving sensor in a laser radar are integrated and integrated is used as the light wave sensor (see, for example, Patent Document 1).

  In the case disclosed in this Patent Document 1, a sensor array having sensitivity to the target infrared wavelength and a sensor array having sensitivity to the laser light wavelength of the laser radar to be used are arranged in the same plane and integrated. An integrated composite type sensor is configured, and the incident light is split into each wavelength, and this sensor is arranged at the focal point.

US Pat. No. 6,882,409 (second page, FIG. 3)

  By the way, in a target acquisition and tracking device that searches, captures and identifies a target by combining an infrared imaging sensor and a laser radar, and further tracks the target, a two-dimensional image of an object existing in the field of view is obtained from an image obtained by the infrared imaging sensor. Image information is acquired, and in the laser radar, distance information is further added to acquire three-dimensional information such as its shape. A series of functions from target search to tracking are realized while individually setting the visual axis, field of view, scanning range, and the like of each sensor.

  However, for example, as described above, when the infrared imaging sensor and the light receiving sensor in the laser radar are integrated and integrated into a composite type sensor, the visual axis of each sensor can be individually set and operated. It becomes difficult. That is, the visual axis and field of view of the infrared imaging sensor that acquires the two-dimensional image information and the directing direction and the scanning range that are the visual axis of the laser radar that acquires the three-dimensional information such as the shape are independent or free. It cannot be selected in combination and is subject to restrictions. In particular, when a target on the ground is captured and tracked from the sky by a flying mobile body or the like, there may be a plurality of target targets at the same time in the field of view in the movement direction. Therefore, in such an environment, for example, while capturing the target in the entire field of view with the two-dimensional image information, three-dimensional information is acquired for different directions in the field of view corresponding to each target target. In some cases, it was difficult to give freedom, and this could hinder operations.

  The present invention has been made in consideration of the above-described circumstances, and improves the visual axis setting and the degree of freedom of the target visual field when acquiring a target three-dimensional shape existing in the visual field of the two-dimensional image, and improves the efficiency. An object of the present invention is to provide a target acquisition / tracking device that often captures and tracks a target.

  In order to achieve the above object, a target acquisition and tracking device of the present invention is a target acquisition and tracking device that acquires and tracks a target from a moving body, and has a predetermined relationship with respect to the moving body and a moving direction of the moving body. A two-dimensional image acquisition means for acquiring two-dimensional image information in which a visual axis is fixed with a depression angle and a predetermined azimuth angle range and an elevation angle range are viewed with respect to the direction of the visual axis; Three-dimensional shape acquisition means for setting the visual axis in an arbitrary direction within the field of view in the means, uniaxially scanning in a direction orthogonal to the visual axis, and acquiring the three-dimensional shape information, and the acquired two-dimensional Control means for controlling the direction of the visual axis of the three-dimensional shape acquisition means and the uniaxial scanning range based on image information and three-dimensional shape information, and when the control means captures the target, Direction of visual axis of the three-dimensional shape acquisition means When matching the direction of the visual axis of the two-dimensional image acquisition means and controlling the uniaxial scanning range to a range corresponding to the azimuth angle range of the visual field of the two-dimensional image acquisition means, when tracking the target, The direction of the visual axis of the three-dimensional shape acquisition means is directed to the target direction detected based on the acquired two-dimensional image information and three-dimensional shape information, and the uniaxial scanning range is limited to include this target. It is characterized by controlling to a range.

  According to the present invention, it is possible to improve the visual axis setting and the degree of freedom of the target visual field when acquiring the target three-dimensional shape existing in the visual field of the two-dimensional image, and efficiently capture and track the target. A target acquisition and tracking device capable of performing the above can be obtained.

The block diagram which shows the structure of one Example of the target acquisition tracking apparatus which concerns on this invention. 4 is an explanatory diagram showing an example of a relationship between a visual axis direction, a uniaxial scanning direction, and a footprint of the laser radar unit 4. FIG. The flowchart for demonstrating operation | movement of the Example of the target tracking apparatus illustrated in FIG. Explanatory drawing which models and shows an example of the relationship between the visual field of the infrared imaging part 3 during the search and capture | acquisition of the target, and the scanning of the laser radar part 4. FIG. Explanatory drawing which models and shows an example of the relationship between the visual axis of the laser radar part 4 during tracking of a target, and the tracking visual field by uniaxial scanning.

  The best mode for carrying out the target acquisition and tracking apparatus according to the present invention will be described below with reference to FIGS.

  FIG. 1 is a block diagram showing the configuration of an embodiment of a target acquisition and tracking apparatus according to the present invention. As illustrated in FIG. 1, the target acquisition and tracking device 1 includes a moving body 2, an infrared imaging unit 3 as a two-dimensional image acquisition unit 3, a laser radar unit 4 as a three-dimensional shape acquisition unit, and a visual axis control unit 5. , And two optical windows 6a and 6b. The mobile body 2 is, for example, a flying object that flies over the sky, and constitutes the target acquisition and tracking device 1 with each unit described later.

  The infrared image capturing unit 3 acquires, as a two-dimensional image acquisition unit, two-dimensional image information having a predetermined azimuth angle range and elevation angle range as a visual field with respect to the direction of the visual axis, and sends the information to the visual axis control unit 5. The visual axis is fixed with a predetermined depression angle with respect to the moving direction of the movable body 2. In this embodiment, the acquired two-dimensional image information is two-dimensional infrared image information of the target visual field. Here, the infrared imaging unit 3 includes an optical system 31 and an infrared detector 32. The optical system 31 is composed of, for example, an optical lens and the like, and condenses infrared light from within the visual field on the infrared detector 32. The infrared detector 32 is an image sensor in which pixels for detecting infrared rays are two-dimensionally arranged on the same focal plane, such as an FPA (Focal Plane Array), and controls the visual axis by acquiring a two-dimensional infrared image. Send to part 5.

  The laser radar unit 4 uses a laser radar as a three-dimensional shape acquisition unit, sets a visual axis based on a driving signal from a visual axis control unit 5 described later, performs uniaxial scanning, and obtains three-dimensional shape information of the scanning range. Is acquired, and the acquisition result is sent to the visual axis control unit 5. In the present embodiment, the direction of uniaxial scanning is the azimuth angle direction of the infrared imaging unit 3 and is 3 by a laser radar having a footprint that is perpendicular to the uniaxial scanning, that is, the elevation angle direction. Dimensional shape information is acquired. The laser radar unit 4 includes a biaxial gimbal 41, a laser light source 42, a transmission optical system 43, a uniaxial scanning mechanism 44, a transmission / reception optical system 45, a reception optical system 46, a laser detector 47, and a signal processing unit 48. ing.

  The biaxial gimbal 41 directs the visual axis of the laser radar unit 4 in a predetermined direction within the visual field of the infrared imaging unit 3 based on a drive signal from the visual axis control unit 5. The laser light source 42 emits pulsed laser light in synchronization with the transmission pulse from the signal processing unit 48, and guides and distributes the laser light to a plurality of fibers. The number of distributions is determined based on the required resolution of the three-dimensional shape information. The transmission optical system 43 adjusts the beam divergence angle so that the laser light from the fiber end matches the optical effective diameter of the uniaxial scanning mechanism 44. The uniaxial scanning mechanism 44 is composed of a one-degree-of-freedom mirror using, for example, a galvanometer mirror or the like, and uniaxially scans the laser beam from the transmission optical system 43 within a predetermined range based on a drive signal from the visual axis control unit 5. The received laser beam as reflected light is received from the transmission / reception optical system 44 and sent to the reception optical system 46. The transmission / reception optical system 45 squeezes the laser light that has passed through the uniaxial scanning mechanism 44 into a predetermined footprint, irradiates it as laser transmission light, and receives the reflected light as reception laser light of the same number as the distribution number in the transmission footprint. And sent to the uniaxial scanning mechanism 43. In the present embodiment, the footprint of the laser beam to be transmitted is reduced with respect to the direction orthogonal to the uniaxial scanning by narrowing the laser light spots according to the number of distributions of the laser light sources 42 to the shape arranged in the direction orthogonal to the uniaxial scanning. In addition, the reflected light corresponding to each spot is received and used as received laser light.

  The relationship between the direction of the visual axis of the laser radar unit 4, the direction of uniaxial scanning, and the footprint is illustrated in FIG. In the example shown in FIG. 2, the biaxial gimbal 41 sets the visual axis to one point in the field of view of the infrared imaging unit 3 looking down from the sky, and the uniaxial scanning mechanism 44 uses the azimuth direction as a reference. Fig. 6 shows the case where the transmission laser beam is scanned. The footprint of the transmission laser light is such that spots corresponding to the number of distributions of the laser light sources 42 are arranged in the direction orthogonal to the scanning direction, that is, in the elevation angle direction, to have a spread, and from each spot. The reflected light is received and used as received laser light.

  The reception optical system 46 adjusts the beam divergence angle of the reception laser light so as to match the optical effective diameter of the fiber for guiding the reception laser light from the uniaxial scanning mechanism 44 to the laser detector 47 in the subsequent stage. A plurality of laser detectors 47 are provided in accordance with the number of distributions of the laser light sources 42, photoelectrically convert each received laser beam, and send it to the signal processing unit 48 as a received pulse. The signal processing unit 48 uses the transmission pulse as a time reference, distance information obtained from the arrival times of the plurality of reception pulses, and the directing direction of the transmission laser light indicated by the drive signal from the visual axis control unit 5 at that time Based on the above, the three-dimensional shape information of the scanning range is acquired and sent to the visual axis control unit 5.

  Based on the two-dimensional image information from the infrared imaging unit 3 and the three-dimensional shape information from the laser radar unit 4, the visual axis control unit 5 determines the direction of the visual axis and the uniaxial scanning range of the laser radar unit 4 as follows. Continue to capture and track the target while controlling the That is, when the target is captured, the direction of the visual axis of the laser radar unit 4 is made coincident with the visual axis of the infrared imaging unit 3, and then the transmitted laser beam corresponds to the azimuth range of the visual field of the infrared imaging unit 3. A drive signal for driving each of the two-axis gimbal 41 and the one-axis scanning mechanism 44 of the laser radar unit 4 is generated and transmitted so as to perform one-dimensional scanning of the range to be performed. As processing for detecting and capturing a target in the field of view, for example, data fusion processing using two-dimensional image information and three-dimensional shape information can be applied.

  On the other hand, when tracking the target, the direction of the visual axis of the laser radar unit 4 is made to coincide with the direction of the target target in the field of view, and then the limited range in which the transmitted laser light includes this target target is one-dimensional. A drive signal for driving each of the biaxial gimbal 41 and the uniaxial scanning mechanism 44 of the laser radar unit 4 is generated and transmitted so as to scan. As a process for tracking the captured target, for example, a method of continuously acquiring three-dimensional shape information of a limited region including the target target and calculating a position by calculating the three-dimensional center of gravity can be applied.

  The optical windows 6a and 6b are covers that are attached to the moving body 2 and have transparency to the target light wave. The optical window 6a is transparent to the infrared light targeted by the infrared imaging unit 3, and the infrared imaging unit 3 receives the infrared light through the optical window 6a. The optical window 6b is transparent to the laser light transmitted and received by the laser radar unit 4, and the laser radar unit 4 transmits and receives the laser light through the optical window 6b.

  Next, with reference to the flowcharts of FIGS. 1, 2 and 3 and the explanatory diagrams of FIGS. 4 and 5, the operation of the target acquisition and tracking apparatus of the present embodiment configured as described above will be described. explain. In the following description, the target capturing / tracking apparatus 1 searches for and captures a target on the ground from the sky and then tracks the target target. FIG. 3 is a flowchart for explaining the operation of the embodiment of the target tracking device 1 illustrated in FIG.

  First, when the target acquisition and tracking device 1 starts moving, acquisition of two-dimensional image information and three-dimensional shape information is started in order to search for and acquire a target on the ground from the sky (ST301). Two-dimensional image information is acquired by the infrared imaging unit 3. The infrared imaging unit 3 has a visual axis fixed with a predetermined depression angle with respect to the moving direction of the moving body so that the ground can be imaged from above, and a predetermined azimuth angle with respect to the direction of the visual axis. And two-dimensional image information with the elevation angle range as the visual field is acquired. The acquired two-dimensional image information is continuously sent to the visual axis control unit 5 (ST302).

  The three-dimensional shape information is acquired by the laser radar unit 4. At the start of acquisition, the visual axis control unit is configured so that the visual axis of the laser radar unit 4 coincides with the direction of the visual axis of the infrared imaging unit 3 and the range corresponding to the azimuth angle of the visual field of the infrared imaging unit 3 is uniaxially scanned. 5 sends a drive signal to the biaxial gimbal 41 and the uniaxial scanning mechanism 44 of the laser radar unit 4 (ST303). The laser radar unit 4 performs scanning based on this setting and acquires three-dimensional shape information. The acquired three-dimensional shape information is continuously sent to the visual axis control unit 5 (ST304).

  The relationship between the field of view of the infrared imaging unit 3 and the scanning of the laser radar unit 4 during target search / capture is modeled in FIG. In the example of FIG. 4, the azimuth angle direction of the visual field of the infrared imaging unit 3 is a cutting width necessary for search and capture, and the visual axis of the laser radar unit 4 matches the visual axis of the infrared imaging unit 3. And set in the center direction of the cutting width. Then, while moving the field of view of the infrared imaging unit 3 along with the movement of itself, the laser beam having a footprint having a spread in the elevation direction is scanned in the azimuth direction, and two-dimensional image information is obtained. Acquisition of 3D shape information is continued. The visual axis control unit 5 detects and captures the target target while performing fusion processing or the like on these to grasp the direction in the field of view and the distance information corresponding thereto (ST305).

  Next, when the target target is captured (Y in ST306), the visual axis of the laser radar unit 4 is directed in the direction of the target in order to track the target, and with respect to a limited range including this target. A drive signal is sent from the visual axis control unit 5 to the biaxial gimbal 41 and the uniaxial scanning mechanism 44 of the laser radar unit 4 so as to perform uniaxial scanning (ST307). The laser radar unit 4 performs scanning based on this setting and acquires three-dimensional shape information. The acquired three-dimensional shape information is sent to the visual axis control unit 5 (ST308).

  The visual axis of the laser radar unit 4 during tracking of the target and the tracking visual field by uniaxial scanning are modeled and illustrated in FIG. In the example of FIG. 5, the visual axis of the laser radar unit 4 is driven by the biaxial gimbal 41 so as to coincide with the target direction, and a limited azimuth range including the target is scanned by the uniaxial scanning mechanism 44. Has been. Further, the footprint of the laser beam at this time is assumed to have a spread with respect to the elevation angle direction as in the capture. In the visual axis control unit 5, the tracking field of view of the laser radar unit 4 is also sequentially updated by sequentially calculating the position for the continuously acquired three-dimensional shape information (ST309). Then, the operation from step ST308 is repeated until the target target tracking end is instructed (ST310). Thereafter, the above operation steps are repeated until an instruction to end the operation of the apparatus is given (ST311).

  As described above, in this embodiment, the infrared imaging unit having a sensor for acquiring two-dimensional image information and the laser radar unit having a sensor for acquiring three-dimensional shape information are separated from each other. The visual axis and field of information, the direction for acquiring the three-dimensional shape information, and the scanning range thereof can be set independently. That is, while the visual axis of the infrared imaging unit matches the moving direction of itself, the visual axis of the laser radar unit matches the direction of the visual axis of the infrared imaging unit when capturing the target, and the infrared imaging unit The three-dimensional shape information is obtained by uniaxial scanning in the azimuth range of the visual field. Further, when tracking the target, the visual axis is set in the direction of the target, and a limited range based on this is uniaxially scanned to obtain the target three-dimensional shape. Therefore, it is possible to improve the visual axis setting when acquiring the target three-dimensional shape existing in the field of view of the two-dimensional image and the degree of freedom of the target field of view, and the target that can efficiently capture and track the target A capture and tracking device can be obtained.

  Note that the present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. Further, various inventions can be formed by appropriately combining a plurality of constituent elements disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, you may combine suitably the component covering different embodiment.

DESCRIPTION OF SYMBOLS 1 Target acquisition tracking apparatus 2 Mobile body 3 Infrared imaging part 4 Laser radar part 5 Visual axis control part 6a, 6b Optical window 31 Optical system 32 Infrared detector 41 Two axis gimbal 42 Laser light source 43 Transmission optical system 44 Uniaxial scanning mechanism 45 Transmission / reception optical system 46 Reception optical system 47 Laser detector 48 Signal processing unit

Claims (3)

A target capturing and tracking device that captures and tracks a target from a moving object,
A mobile body,
A visual axis is fixed with a predetermined depression angle with respect to the moving direction of the moving body, and two-dimensional image information with a predetermined azimuth angle range and elevation angle range as a field of view is acquired with respect to the direction of the visual axis 2 Dimensional image acquisition means;
A three-dimensional shape acquisition unit that sets a visual axis in an arbitrary direction within a visual field in the two-dimensional image acquisition unit, and acquires the three-dimensional shape information by uniaxial scanning in a direction orthogonal to the visual axis;
Control means for controlling the direction of the visual axis of the three-dimensional shape acquisition means and the uniaxial scanning range based on the acquired two-dimensional image information and three-dimensional shape information;
The control means includes
When capturing the target,
The direction of the visual axis of the three-dimensional shape acquisition unit is matched with the direction of the visual axis of the two-dimensional image acquisition unit, and the uniaxial scanning range is set to a range corresponding to the azimuth range of the visual field of the two-dimensional image acquisition unit. Control
When tracking the target,
The direction of the visual axis of the three-dimensional shape acquisition means is directed to the target direction detected based on the acquired two-dimensional image information and three-dimensional shape information, and the uniaxial scanning range is limited to include this target. A target acquisition and tracking device characterized by controlling to a range.   The target acquisition and tracking device according to claim 1, wherein the two-dimensional image information acquired by the two-dimensional image acquisition means is two-dimensional infrared image information of the visual field.   3. The target acquisition and tracking device according to claim 1, wherein the three-dimensional shape acquisition unit is acquired by a laser radar having a footprint having a spread in a direction orthogonal to the uniaxial scanning. .

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