JP3032703B2 - Pointing control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pointing control device for capturing a target by using an antenna, an optical instrument, or the like.

[0002]

2. Description of the Related Art FIGS. 1 and 2 show the configuration of a device for capturing a target by an antenna, and FIGS. 3 and 4 show the configuration of a device for capturing a target by an optical instrument (for example, a television camera or a telescope). It is shown.

First, the apparatus shown in FIGS. 1 and 2 is an antenna 1 for receiving a signal transmitted or reflected by a target.
It has 0. The antenna 10 has a sharp directivity, and its beam direction (in this case, the direction of the antenna 10) can be changed by driving the elevation axis motor 12 and the azimuth axis motor 14. That is,
The elevation axis motor 12 has an azimuth axis motor 14
Are fixed on the pedestal 16, respectively, the elevation axis 18 is defined by the azimuth axis 20, and the azimuth axis 20 is defined by the pedestal 16.
Since the antenna 10 is rotatably supported, the antenna 10 can be rotated around the elevation axis 18 or around the azimuth axis 20 by operating the elevation axis motor 12 and the azimuth axis motor 14, respectively. Note that, in FIG.
Are hidden by the elevation axis motor 12. Reference numeral 22 denotes a belt.

On the pedestal 16, an inclinometer 24, a magnetic compass 26 and a receiver 28 are further arranged. Although not shown in FIG. 1, an azimuth axis / elevation axis control device 30 shown in FIG. The azimuth axis / elevation axis control device 30 generates inclination data indicating the inclination angle of the pedestal 16 with respect to the horizontal plane obtained from the inclinometer 24, and azimuth data indicating the azimuth of the pedestal 16 with respect to magnetic north (or true north) obtained from the magnetic compass 26. , A control signal for each of the elevation axis 18 and the azimuth axis 20 is generated, and the elevation axis motor 12
Alternatively, it is supplied to the azimuth axis motor 14. The elevation axis motor 12 and the azimuth axis motor 14 are driven according to this control signal,
The mechanical output is transmitted to the elevation axis 18 or the azimuth axis 20 via the corresponding reducer 36 or 38. The azimuth axis / elevation axis controller 30 also monitors the output of the receiver 28 as needed, for example, the presence or absence of a target acquisition signal indicating that the target (for example, a satellite) is being acquired by the antenna 10. FIG.
Reference numeral 40 denotes an operation panel which is operated by a user and gives a command to the azimuth axis / elevation angle control device 30.

[0005] The apparatus shown in FIGS. 3 and 4 captures the target not by the antenna 10 but by an optical instrument 42 such as a television camera. An image processing (recognition) device indicated by reference numeral 46 in FIG. 4 outputs a target acquisition signal under the same conditions as those of the receiver 28. Reference numeral 48 denotes a television for monitoring an image obtained by the optical instrument 42.

[0006] In each of these devices, the orientation of the pedestal 16 (more specifically, the pedestal 1
While detecting the azimuth of a moving body such as a vehicle on which the pedestal 6 is mounted, the inclination angle of the pedestal 16 (more specifically, the inclination angle of the pedestal 16 with respect to a horizontal plane) is detected from the output of the inclinometer 24. Further, the azimuth axis / elevation angle control device 30 performs a coordinate conversion operation using the detected inclination angle, and thereby sets the azimuth and elevation angle control targets based on the detected azimuth.

First, as shown in FIG. 5, a reference coordinate system (usually a horizontal true north coordinate system where true north is X ₀ ) set on a horizontal plane is X ₀ Y ₀ Z ₀ and there is no inclination. Pedestal 1
Horizontal orthogonal coordinate system X ₁ Y ₁ Z ₁ (the horizontal base coordinate system) to the baseline orientation phi _v and X ₁ of 6, the orthogonal coordinate system when the pitch P is generated (pitch coordinate system) X ₂ Y ₂ Z _2. An orthogonal coordinate system (roll pitch coordinate system) when a roll R is also generated is represented as X ₃ Y ₃ Z ₃ . Then, the position vector [X _S0 , Y _S0 , Z _S0 ] ^t of the target S in the reference coordinate system X ₀ Y ₀ Z ₀ and the roll pitch coordinate system X ₃ Y ₃
Position vector of the target S in _{Z 3 [X S3, Y S3} ,
Z _S3 ] ^t ,

(Equation 1) Holds. On the other hand, the polar Cartesian coordinate conversion formula

(Equation 2) Holds, and by transforming the expression on the left side of Expression (2),

(Equation 3) Is obtained. Therefore, by substituting the right side of equation (1) into X _S3 , Y _S3 , and Z _S3 in equation (3), the control targets φ _S3 and θ of the azimuth and elevation of the target S in a state where the pedestal 16 is inclined. You can get _S3 .

FIG. 6 shows an azimuth axis / elevation axis control device 3 for searching for a target S based on equations (1) to (3).
0 is shown. As shown in this figure, the azimuth axis / elevation axis control device 30 firstly uses equations (1) to
Based on (3), control targets φ _S3 and θ _S3 of the azimuth and elevation of the target _S are obtained (100). Azimuth / elevation axis controller 3
0 controls the azimuth axis motor 14 and the elevation axis motor 12 in accordance with the determined control targets φ _S3 and θ _S3 (10
2). When the target S is captured by the antenna 10 or the optical instrument 42 as a result of this control, a target capture signal is generated.
When the azimuth axis / elevation axis control device 30 detects the target capture signal, it exits the routine of FIG. 6 and shifts to a routine for finely adjusting the azimuth / elevation angle of the antenna 10 or the optical instrument 42 (104). Otherwise, return to step 102.

Here, in step 100, the azimuth axis / elevation axis controller 30 also sets a search range for the azimuth. That is, since an error may occur in the output of the magnetic compass 26 and the like, a range is set for the control target φ _S3 so that the error can be compensated. As described above, since the condition determination in step 104 is not satisfied, when step 102 is executed again, the control target φ _S3 is updated within this search range. If the predetermined time has passed without the condition determination of step 104 being satisfied even by the search by such update (106), the azimuth axis
The elevation axis control device 30 expands the search range for the azimuth and dithers (dither) the elevation angle control target θ _S3.
ing) and restart the search (108), and steps 110 and 112 similar to steps 104 and 106.
repeat. If the elapse of the predetermined time is detected in step 112, an alarm display is issued to the user or the like (114), and the operation in FIG. 6 ends.

[0010]

However, in such a control method, the elevation angle of a capturing device such as an antenna may not be accurately controlled. That is, in the above-described method, a search is performed for the azimuth, and a capture accuracy sufficient for practical use can be obtained. However, if the azimuth error included in the magnetic compass output or the like is a large value of, for example, 10 ° or more, this error is controlled by the elevation angle. Will be affected.

Here, the azimuth obtained by the magnetic compass 26 and actually including an error is represented by φ _VC . Further, the control targets φ _S3 and θ _S3 obtained by substituting this φ _VC into the equations (1) to (3) are represented as φ _S3C and θ _S3C , respectively. In addition, the angle added to φ _S3C within the search range is denoted as φ _SRC . In the above-described method, no addition is made to the elevation angle (except for the effect of dithering), so that the errors of the azimuth and the elevation angle of the antenna 10 with respect to the azimuth and the elevation angle of the target S are Δφ _S3C and Δθ.
_S3C is

(Equation 4) It is represented by As is clear from this equation, the additional angle φ
_{Even if the} azimuth error Δφ _S3C becomes almost zero by updating the _SRC , the elevation angle error Δθ _S3C does not always become zero or a sufficiently small value.

SUMMARY OF THE INVENTION It is an object of the present invention to solve such a problem. By improving the control logic, it is possible to accurately capture a target not only in the azimuth but also in the elevation in the azimuth search. The purpose is to do.

[0013]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention relates to a capturing device such as an antenna or an optical instrument supported on a pedestal so as to be rotatable around an azimuth axis and an elevation axis. In the pointing control device for capturing the target, means for detecting the inclination angle of the pedestal coordinate system fixed to the pedestal, and the azimuth and elevation of the target and the virtual value of the pedestal azimuth in the reference coordinate system assumed on the horizontal plane Means for estimating the azimuth and elevation of the target in the pedestal coordinate system based on the coordinate conversion operation using the above-mentioned inclination angle, and the azimuth axis and the elevation axis Means for rotating around, and performing the estimation operation and the rotation operation while updating the virtual value at least until the target is captured by the capturing device, so that the target Means for searching the position and elevation, characterized in that it comprises a.

The present invention is further characterized in that the virtual value is initially set based on azimuth information which is provided by eye measurement or a pedestal azimuth detecting device and generally includes an error. In addition, the present invention is characterized in that when a target is captured, the capturing device generates a target capture signal indicating that, and terminates the search according to the target capture signal.

In the present invention, when searching for the azimuth and the elevation angle of the target, not the control target of the azimuth but the virtual value of the pedestal azimuth is sequentially updated. That is, the virtual value of the pedestal azimuth (the azimuth information given by the eye measurement or the pedestal azimuth detecting device), which is the amount in which the error is originally included, is updated by adding an angle or the like. Therefore, as a result of the update, not only the azimuth but also the control target of the elevation angle is sequentially changed through the coordinate conversion operation using the inclination angle, and the control error of the azimuth and the elevation angle becomes almost simultaneously zero. As described above, in the present invention, even when the virtual value of the pedestal azimuth includes an error in the initial stage, both the azimuth and the elevation angle can be accurately controlled, and the target can be searched and captured appropriately. This search may be terminated with the target acquisition signal.

[0016]

Preferred embodiments of the present invention will be described below with reference to the drawings. In addition, the present invention, FIGS.
Since the present invention can be implemented under the apparatus configuration shown in FIG. 4, the following description is based on the apparatus configuration shown in FIGS. 1 to 4 and uses the same reference numerals as those in the procedures shown in FIGS. 5 and 6. The invention is not limited to the above device configuration.

FIG. 7 shows a search procedure executed by the azimuth axis / elevation axis controller 30 in one embodiment of the present invention. In this figure, steps 100, 102 and 108 in FIG.
A, 102A and 108A are being executed, respectively.
If the elapse of the predetermined time is detected in step 106, step 100 is executed instead of step 102A.
The operation shifts to A.

In step 100A, a search range is set not with respect to the azimuth information after the coordinate transformation, that is, with respect to the azimuth φ _VC given from the magnetic compass 26, but with respect to φ _{S3 shown in the} equation (3). In step 102A, φ _S3 and θ _S3 are obtained by substituting the value (virtual moving body direction) φ _VV belonging to this search range into the moving body direction φ _V in equations (1) to (3). . Φ _S3 and θ _S3 obtained in this way are treated as control targets based on φ _VV, that is, control targets φ _S3V and θ _S3V relating to azimuth and elevation, and these control targets φ _S3V and θ _S3V
The azimuth axis motor 14 and the elevation axis motor 12 are controlled based on _S3V . This control is performed until the condition determination in step 104 is satisfied, and within a predetermined time (10
6) It is repeatedly executed while sequentially changing the value of φ _VV within the set search range. Note that, also in step 108A, similarly to step 100A, the search range relates to the azimuth φ _VC obtained by the magnetic compass 26. Further, in step 108A, unlike step 108 in the conventional example, dithering relating to the elevation control target θ _S3V is not executed.

As described above, in the present embodiment, the search range is set not for the azimuth control target φ _S3V but for the azimuth φ _VC , and during the search, the value of the azimuth φ _VV is gradually updated within this search range. Is done. Also, φ
_When the value of _VV is updated, the effect of the update appears not only on the azimuth control target φ _S3V but also on the elevation angle control target θ _S3V through the calculations of Equations (1) to (3). The control errors Δφ _{S3 V} and Δθ _{S3V for} azimuth and elevation respectively are

(Equation 5) When the value φ _VV substituted for the direction φ _V in the equations (1) to (3) becomes substantially equal to the true φ _V , the following equation is obtained.

(Equation 6) As shown in (2), the control errors Δφ _S3V and Δθ _S3V become substantially zero almost simultaneously. Therefore, according to the present embodiment, the search control around the azimuth axis causes a suitable search to be simultaneously performed around the elevation axis 18. As a result, the output of the magnetic compass 26 includes a relatively large error. Even if the search is performed, it is possible to execute an accurate search without being affected by the search.

In the above description, the azimuth φ _VC is given from the magnetic compass 26. However, the present invention does not need to limit such an initial setting operation. It may be used as φ _VC .

It should be noted that the reference coordinate system is a horizontal coordinate system (even rectangular coordinates,
Polar coordinates may be used). Therefore, the effect of the present invention can be expected even if the reference coordinate system is not necessarily the horizontal true north coordinate system. For example, X ₁ Y ₁ Z ₁ in FIG. 5 may be considered as a reference coordinate system as it is.

When using an estimated value that may cause a large error in the azimuth and elevation angle (especially, elevation angle) of the target in the reference coordinate system, it is necessary to provide auxiliary means such as dithering on the elevation axis. However, according to the present invention, the dithering amplitude can be kept small compared to the conventional method, and therefore, it can be expected that the average search time can be shortened.

[0023]

As described above, according to the present invention,
When searching for the azimuth and elevation angle of the target, since the virtual value of the pedestal azimuth was updated sequentially instead of the azimuth control target,
For example, even if the virtual value of the pedestal direction provided by the eye measurement or the pedestal direction detection device includes an error, both the azimuth and the elevation angle can be accurately searched, and the target can be appropriately captured.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an appearance of a device for capturing a target by an antenna.

FIG. 2 is a block diagram showing a functional configuration of the device shown in FIG.

FIG. 3 is a perspective view showing an external appearance of a device for capturing a target with an optical instrument such as a television camera.

FIG. 4 is a block diagram showing a functional configuration of the device shown in FIG.

FIG. 5 is a diagram showing a relationship between respective rectangular coordinate systems.

FIG. 6 is a flowchart showing a search procedure in a device according to a conventional example.

FIG. 7 is a flowchart illustrating a search procedure in an apparatus according to an embodiment of the present invention.

[Explanation of symbols]

Reference Signs List 10 antenna, 12 elevation axis motor, 14 azimuth axis motor, 16 pedestal, 18 elevation angle axis, 20 azimuth axis, 24
Inclinometer, 26 magnetic compass, 28 receiver, 30
Azimuth axis / elevation axis control device, 42 Optical instruments such as TV camera, 46 Image processing (recognition) device.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H01Q 3/00-3/46 H01Q 21/00-21/30 H01Q 23/00 H01Q 25/00-25/04 JICST file (JOIS)

Claims (3)

(57) [Claims] 1. A directional control device that captures a target with a capturing device such as an antenna or an optical instrument supported on a pedestal so as to be rotatable around an azimuth axis and an elevation axis, wherein a tilt angle of the pedestal is detected. Means for performing, based on a virtual value of the azimuth and elevation angle of the target in the reference coordinate system assumed on the horizontal plane and the pedestal azimuth, and performing a coordinate conversion operation using the tilt angle, the target in the pedestal coordinate system fixed to the pedestal. Means for estimating the azimuth and elevation, means for rotating the capturing device around the azimuth axis and the elevation axis using the estimated values of the azimuth and elevation of the target as control targets, and at least until the target is captured by the capturing device. Means for searching for a target azimuth and elevation by executing the estimation operation and the rotation operation while updating the virtual value. Apparatus. 2. The pointing control device according to claim 1, wherein the virtual value is initially set based on azimuth information provided by eye measurement or a pedestal azimuth detecting device and generally including an error. 3. The pointing control device according to claim 1, wherein when the target is captured, the capturing device generates a target capture signal indicating the fact, wherein a means for terminating the search according to the target capture signal is provided. Characteristic pointing control device.