JPH1020212A - Rotation controller for astronomical dome - Google Patents

Abstract

PROBLEM TO BE SOLVED: To accurately rotate an astronomical dome so that a slit may be always aligned with the top of a lens barrel by correcting a signal transmitted from a 1st control part to a driving part so that an actual rotational amount detected by a 2nd sensor may agree with a necessary rotational amount. SOLUTION: Information from two encoders 6 and 7 is transmitted to the 1st control part 10 so as to obtain the position of the top of the lens barrel 3 and calculate the necessary rotational amount of the astronomical dome 1. The dome 1 is rotated by a driving part 11 based on the signal from the control part 10. The actual rotational amount of the rotated dome 1 is detected by photoelectric sensors 8 and 9 and the detected information is transmitted to a 2nd control part 12. The control part 12 corrects the signal transmitted from the control part 10 to the driving part 11 so that the actual rotational amount detected by the sensors 8 and 9 may agree with the necessary rotational amount transmitted from the control part 10 as the signal. Thus, the dome 1 is accurately rotated by the necessary rotational amount even when the slip of a roller or the wear of the roller is caused in the driving part 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a celestial dome rotation control device.

[0002]

2. Description of the Related Art An installation surface in a celestial dome is stationary, and the celestial dome rotates with respect to this installation surface. An astronomical telescope is fixed to an installation surface inside the astronomical dome, and a lens barrel of the astronomical telescope can rotate in the declination direction and the right ascension direction in order to track an observation target.
Therefore, it is necessary to rotate the celestial dome so that the slit formed in the celestial dome always coincides with the distal end of the lens barrel (Japanese Patent Laid-Open No. 6-15888 as a similar technique).
No. 6).

[0003]

However, conventionally, there has been no device for automatically rotating the celestial dome accurately in accordance with the movement of the lens barrel of the astronomical telescope. Therefore, it is necessary to manually rotate the dome in accordance with the movement of the astronomical telescope, which is very troublesome.

[0004] Even if the rotation of the celestial dome is automated,
Since the celestial dome itself is a considerably heavy object, slippage occurs in the driving unit during automatic control, or errors easily occur due to wear of the driving unit, etc., and accurate rotation control of the celestial dome can be performed. Can not.

The present invention has been made by paying attention to such a conventional technique, and a rotation control of a celestial dome capable of accurately rotating the celestial dome so that the slit always coincides with the tip of the lens barrel. An apparatus is provided.

[0006]

SUMMARY OF THE INVENTION A celestial dome rotation control apparatus according to the present invention includes a first sensor for detecting a position of a tip of a lens barrel of an astronomical telescope, and a rotation of the celestial dome based on information from the first sensor. A first control unit that obtains the amount and emits the signal, a driving unit that rotates the celestial dome based on a signal from the first control unit, and an actual rotation amount of the celestial dome rotated by the driving unit with respect to the installation surface. A second sensor for detecting, and a second control unit for correcting a signal sent from the first control unit to the drive unit such that an actual rotation amount detected by the second sensor matches the required rotation amount. ing.

According to the celestial dome rotation control apparatus of the present invention, the actual rotation amount detected by the second sensor and the first rotation
Since the second control unit corrects the signal sent from the first control unit to the drive unit so that the required rotation amount sent as a signal from the control unit matches, even if an error occurs in the drive unit,
The error can be corrected and the celestial dome can be accurately rotated by the required rotation amount. Therefore, since the actual amount of rotation completely matches the calculated required amount of rotation, even if the target point (star) is tracked by the astronomical telescope barrel, the slit always matches the tip of the barrel, and Can concentrate on astronomical observations.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to FIGS. Reference numeral 1 denotes a celestial dome, which can rotate with respect to an immovable installation surface G inside. The celestial dome 1 has a slit 1a formed therein.

The astronomical telescope 2 is fixed to the installation surface G. The astronomical telescope 2 has a structure in which a lens barrel 3 is supported by an arm 5 of an equatorial mount 4. The arm 5 is substantially U-shaped, and has a predetermined angle with respect to the installation surface G so as to be parallel to the earth's earth axis.

The lens barrel 3 is rotatably supported in the declination direction A about the declination axis α at the tip of the arm 5, and the arm 5 is centered on the equatorial axis β of the equatorial mount 4. The lens barrel 3 is supported rotatably in the right ascension direction B. Therefore, the lens barrel 3
Is rotated in the declination direction A to capture a target point in the celestial body, and then the lens barrel 3 is rotated in the right ascension direction B to track the target point. A limit sensor (not shown) is provided on the declination axis α, and controls the rotation angle of the lens barrel 3 so that the tip of the lens barrel 3 does not fall below the horizontal. ing. Therefore, below the celestial dome 1, the blind spot D where the tip of the lens barrel 3 does not face in the entire rotation range.
Exists.

As described above, it is necessary to rotate the celestial dome 1 in accordance with the lens barrel 3 of the astronomical telescope 2 which rotates following the target point in the celestial body. That is, it is necessary to rotate the dome 1 so that the slit 1 a always corresponds to the tip of the lens barrel 3.

Next, a rotation control device of the celestial dome 1 will be described. At the tip of the arm 5 of the astronomical telescope 2, an encoder 6 is provided as a “first sensor” for detecting the amount of rotation of the lens barrel 3 about the declination axis α. An encoder 7 is provided as another "first sensor" for detecting the amount of rotation.

Further, in the blind spot D at the lower end of the celestial dome 1, two white and black patterns P are provided vertically in the circumferential direction. Each of the upper and lower patterns P has a ratio of white and black of 50%, and has a phase difference of 90 ° between the upper and lower patterns. Therefore, the white and black of the upper and lower patterns P are shifted by 50% (see FIG. 2). The direction of rotation can be determined from this vertical shift. Two photoelectric sensors 8 and 9 as “second sensors” for reading the respective patterns P are provided at the end of the installation surface G. These photoelectric sensors 8 and 9
Are physically electrically insulated by an insulating material such as bakelite or Duracon.

The upper and lower patterns P are vertically shifted in phase as described above, and the interval between the black and white portions of each pattern P is 3 cm (in the drawings, the pattern P is exaggerated for easy understanding). ing). Since the accuracy between the tip of the lens barrel 3 and the slit 1a does not matter in an error of about 3 to 5 cm, the black and white interval of the pattern P is set within the range. Since the rotation is controlled based on the interval of about 3 to 5 cm as described above, there is no problem even when the dome 1 rotates slightly.

The information from the two encoders 6, 7 is
Sent to control unit 10. Then, the first controller 10 obtains the tip position of the lens barrel 3 based on the information from the encoders 6 and 7, and calculates the required rotation amount of the celestial dome 1.

Then, the celestial dome 1 is rotated by the drive unit 11 based on a signal from the first control unit 10.
The driving unit 11 includes a motor, a gear, a roller, and the like.
The large and heavy celestial dome 1 is slowly rotated.

The celestial dome 1 rotated by the drive unit 11
Is actually detected by the photoelectric sensors 8 and 9. The information detected by the photoelectric sensors 8 and 9 is sent to the second control unit 12. Then, the second control unit 1 is controlled so that the actual rotation amount detected by the photoelectric sensors 8 and 9 matches the required rotation amount transmitted as a signal from the first control unit 10.
2 corrects the signal sent from the first control unit 10 to the drive unit 11. Therefore, even if roller slippage or roller wear occurs in the drive unit 11, the celestial dome 1 can be accurately rotated by the required rotation amount. As described above, since the actual amount of rotation completely coincides with the calculated required amount of rotation, even if the target point (star) is tracked for a long time by the lens barrel 3 of the astronomical telescope 2, the slit 1a is always in the lens barrel. According to the 3 tips, the observer can concentrate on astronomical observation or photography.

In this embodiment, the photoelectric sensors 8 and
9 is electrically insulated, so that it is not affected by electric noise from the cable line or the like of the drive unit 11.

In the above description, the encoders 6 and 7 are taken as examples of the "first sensor", but the present invention is not limited to this. Also, the black-and-white putter P and the photoelectric sensors 8 and 9 have been described as examples of the “second sensor”, but the present invention is not limited to this.

[0020]

The dome rotation control apparatus according to the present invention has the contents as described above. Since the dome rotates accurately with respect to the lens barrel of the astronomical telescope, the astronomical telescope and the slit are controlled. You can do long-term observations and photography without worrying about the positional relationship between them.

[Brief description of the drawings]

FIG. 1 is a view including a partial flowchart showing a celestial dome rotation control device according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a second sensor.

[Explanation of symbols]

 Reference Signs List 1 astronomical dome 1a slit 2 astronomical telescope 3 lens barrel 6, 7 encoder (first sensor) 8, 9 photoelectric sensor (second sensor) 10 first control unit 11 drive unit 12 second control unit G installation surface α declination axis β RA axis A Declination direction B RA direction P pattern

Claims (4)

[Claims] An celestial dome having a slit formed on an immovable installation surface is rotatably provided, and a lens barrel is rotatable in a declination direction and a right ascension direction on an installation surface in the celestial dome. A astronomical dome rotation control device that installs an astronomical telescope, and rotates the astronomical dome so that the slit always coincides with the barrel end of the astronomical telescope. A sensor, a first control unit that obtains a required rotation amount of the celestial dome based on information from the first sensor and issues a signal, and a driving unit that rotates the celestial dome based on a signal from the first control unit; A second sensor that detects an actual rotation amount of the celestial dome rotated by the driving unit with respect to the installation surface, and a first control unit that adjusts the actual rotation amount detected by the second sensor to the required rotation amount. To drive Rotation control device celestial dome which is characterized in that it comprises a second control unit for correcting a signal that is, a. 2. The dome rotation control device according to claim 1, wherein the second sensor is electrically insulated. 3. The celestial dome rotation control device according to claim 1, wherein the first sensor is an encoder that detects a rotation amount of the lens barrel about the declination axis and a rotation amount about the right ascension axis. . 4. The celestial dome rotation control device according to claim 1, wherein the second sensor is a photoelectric sensor for reading a black-and-white pattern provided at a blind spot at a lower end of the celestial dome.