JP5658084B2 - Astronomical tracking system - Google Patents

Description

  The present invention relates to an astronomical automatic tracking device that tracks an celestial object to be observed within the field of view of an astronomical telescope.

  When observing a celestial body such as a star from the earth, the celestial body rotates once a day. This is called diurnal motion of celestial bodies. This happens because the earth is rotating around the earth's axis. A star moves at a constant speed that is almost the same as the speed of diurnal motion. The moving speed of this star is called the stellar speed.

  For this reason, when a star is observed with the astronomical telescope fixed, the star moves in a predetermined direction within the field of view and then disappears from the field of view. Therefore, when observing a star, etc., it is necessary to track the astronomical telescope to the celestial body.

  There are two main types of astronomical telescope mounts for tracking celestial bodies: the equatorial mount and the pedestal stand. Each of the gantry is a gantry that supports the telescope barrel so as to be rotatable about the first and second axes, and generates first and second driving forces for rotating the telescope barrel about each axis. The motor is connected to each drive force transmission mechanism.

  In the present specification, a conventional example of an celestial automatic tracking device in an equator ritual will be described.

  FIG. 1 shows a conventional automatic astronomical tracking device having an equator. First, there are two orthogonal axes called a telescope barrel 1, an equatorial mount 2, an ecliptic axis 3 (also called a polar axis) and a declination axis 4. After adjusting and fixing the direction of the red meridian axis 3 (polar axis 3) to be parallel to the direction of the earth's earth axis, the red meridian axis 3 (polar axis 3) is rotated in the direction of the diurnal motion. As a result, the celestial body can always be in the field of view.

  The astronomical axis 3 (polar axis 3) and the declination axis 4 of the automatic celestial body tracking apparatus shown in FIG. 10 is connected. As a configuration for driving each motor under constant control, motor drivers 7 and 11 for supplying a driver signal to each motor, and pulse generators 8 and 12 for supplying an oscillation pulse to each motor driver. And a controller 13 for supplying a control signal to each pulse generator. The ecliptic axis 3 and the declination axis 4 are respectively provided with an ecliptic axis encoder 14 and a declination axis encoder 15 for detecting the rotation angle of each axis, whereby the controller 13 is an object to be observed. The position of a certain celestial body on the equatorial coordinates can be detected. In general, the encoder has a resolution of about 120 arc seconds.

  When star tracking is performed, the declination motor 10 stops, and only the red longitude motor 6 generates a driving force to rotate the red longitude axis 3. If the rotational speed (angular velocity) of the red meridian axis 3 exactly matches the stellar hour speed, the celestial automatic tracking device will accurately track the star, and the star should be stationary in the field of view. However, in practice, there is an error in tracking. Such an error is called a tracking error.

  Possible causes of this tracking error are firstly the deviation of the red meridian axis 3 (polar axis 3), secondly the periodic motion described later, and thirdly the atmospheric difference. In order to reduce the tracking error due to these causes, the following has been conventionally performed.

  First, with regard to the tracking error due to the deviation of the first red meridian axis 3 (polar axis 3), the error can be reduced by adjusting the red meridian axis 3 (polar axis 3) to the earth's earth axis over time. It is decreasing.

  Next, what is conventionally performed to reduce the tracking error due to the second periodic motion will be described. This periodic motion is a phenomenon in which a star repeats moving in the ascension direction and lagging at regular intervals within the telescope's field of view. Possible causes of this phenomenon include uneven tooth surfaces of the worm gear. The tracking error due to this periodic motion can be reduced by setting the exposure time to an extremely short time, but the exposure time required for observing astronomical photographs and images is generally required to be several minutes or longer. Therefore, tracking errors due to periodic motion cannot be ignored.

  As a method for reducing such tracking error due to periodic motion, it is known to use an auto guide device based on CCD images. In this method, a CCD is installed in the sub-telescope to detect a deviation of the target star, and the drive circuit is controlled based on the detection signal. That is, one or more bright stars in the vicinity of the celestial object to be observed are selected as guide stars, and an image of light incident on the celestial telescope is captured by the CCD camera. If the main body 1 is driven so that the guide star is always at a predetermined reference position in the image by the CCD camera, as a result, the astronomical object to be observed is tracked.

  However, in order to make the auto guide device function effectively, it is necessary to know in advance the function of the device and to make advance preparations such as setting the CCD camera and guiding an appropriate star in the field of view.

  Next, what is conventionally done to reduce the tracking error caused by the third atmospheric difference will be described. The atmosphere surrounding the earth has a refraction property that bends the path of light, and all the stars other than the zenith appear to float. The degree increases as it approaches the horizon from the zenith. As a result, the stellar velocity of the celestial object decreases as the celestial object approaches the horizon. Such a phenomenon is generally called atmospheric difference.

  Such tracking errors due to atmospheric differences occur in observations of celestial objects other than those near the zenith, so conventionally tracking errors have been reduced by limiting the celestial object to be photographed to those near the zenith.

  However, when shooting a celestial object other than the vicinity of the zenith, tracking errors due to atmospheric differences occur, and in such a case, the observer simply made adjustments based on experience and intuition.

Japanese Utility Model Publication No. 5-84920 JP-A-11-72718

  Conventional automatic celestial tracking devices have been configured as described above and have been set, but there is a need to further reduce tracking errors.

  The present invention has been made in view of such circumstances, and an object thereof is to reduce tracking errors.

  In order to solve the above-described problems, the present invention includes a telescope barrel, a pedestal that supports the telescope barrel so as to be rotatable about two axes of a first axis and a second axis, and a position around the first axis. Generated by a first motor for generating a driving force for rotating the telescope barrel, a second motor for generating a driving force for rotating the telescope barrel about the second axis, and the first motor. A first driving force transmission mechanism for transmitting a driving force to the first shaft; a second driving force transmission mechanism for transmitting a driving force generated by the second motor to the second shaft; and the first motor. A first control system for controlling, a second control system for controlling the second motor, a first encoder for detecting the first shaft rotation angle signal, and a second encoder for detecting the second shaft rotation angle signal; A celestial body automatic tracking device comprising: And performing correction of the tracking speed of the celestial based on 1 axial rotation angle signal and / or the second shaft rotational angle signal.

  As described above, the present invention can reduce the tracking error.

FIG. 1 is a conceptual diagram showing a conventional celestial automatic tracking device in an equator ritual. FIG. 2 is a conceptual diagram illustrating the celestial automatic tracking device according to the first embodiment. FIG. 3 is a flowchart showing an outline of an example of feedback control. FIG. 4 is an explanatory diagram of a method for measuring one period of the feedback encoder pulse. FIG. 5 is a conceptual diagram illustrating the astronomical automatic tracking device according to the second embodiment. FIG. 6 is a conceptual diagram illustrating an astronomical automatic tracking device according to the third embodiment. FIG. 7 is a flowchart illustrating an outline of an example of the operation of the astronomical object tracking device according to the third embodiment. FIG. 8 is a conceptual diagram illustrating an astronomical automatic tracking device according to the fourth embodiment. FIG. 9 is a flowchart illustrating an outline of an example of the feedback control operation in the fourth embodiment. FIG. 10 shows the result of measuring the tracking error using the astronomical automatic tracking device of the second embodiment. FIG. 11 shows the result of measuring the tracking error using a conventional astronomical automatic tracking device.

  Hereinafter, embodiments of the present invention will be described in detail.

  The inventor of the present invention has invented a technique for performing feedback control using an encoder pulse supplied from an encoder as a result of repeating research and experiments on a technique for correcting a tracking error.

  FIG. 2 is a conceptual diagram of the celestial automatic tracking device according to the first embodiment of the present invention. The telescope barrel 1, the driving force transmission mechanisms 5 and 9, the motors 6 and 10, the motor drivers 7 and 11, the pulse generator 12 and the declination axis encoder 15 are the same as the conventional automatic astronomical tracking device (FIG. 1). .

  The red meridian axis encoder 18 is directly connected to the red meridian axis 3. In addition, the red meridian encoder 18 has a higher resolution than the conventional red meridian encoder 14. Specifically, it is desirable that the resolution of the encoder is about 1 sec to 15 sec. The reason will be described later.

  The red meridian encoder 18 supplies encoder pulses to both the controller 17 and the pulse generator 16.

  The pulse generator 16 performs feedback control using the feedback encoder pulse supplied from the red longitude encoder 18.

  Next, an example of this feedback control will be described with reference to FIGS.

  FIG. 3 is a flowchart showing the operation of the pulse generator 16 in an example of feedback control.

  First, as soon as the tracking operation of the celestial body starts, the red longitude axis encoder 18 starts supplying encoder pulses to the pulse generator 16. In this specification, the encoder pulse supplied to the pulse generator 16 may be referred to as a feedback encoder pulse.

  The pulse generator 16 has a clock pulse generation circuit and a clock pulse number measurement circuit (not shown). As conceptually shown in FIG. 4, the number of clock pulses in one cycle of the feedback encoder pulse supplied to the pulse generator 16. Is measured (S11). Here, one cycle means one unit of resolution of the red meridian axis encoder 18.

  Next, the pulse generator 16 calculates the difference between the number of clock pulses in one cycle of the measured feedback encoder pulse and the expected number of clock pulses (S12).

  Thereafter, when there is a difference in the number of pulses, the pulse generator 16 supplies the corrected oscillation pulse to the motor driver 7 (S13). Note that a corrected oscillation pulse may be supplied when the difference in the number of pulses is greater than or equal to a predetermined value.

  After that, the pulse generator 16 repeats this feedback control (S11 to S13) while tracking the celestial body.

  When the tracking of the celestial object is completed, the pulse generator 16 ends the feedback control.

  By performing the feedback control as described above, the tracking error can be reduced.

  Next, the reason why it is desirable to set the resolution of the red meridian encoder to 1 to 15 arc seconds will be described.

  The allowable range of tracking error for astronomical objects varies depending on the focal length of the photographic lens, etc., but in general, if the target tracking error is within about ± 1 sec, it will be acceptable under most shooting conditions. It is said that there is. Therefore, it is desirable to provide an astronomical automatic tracking device in which the magnitude of the tracking error is within about ± 1 sec.

  Therefore, as a result of repeated research on the resolution of an encoder capable of setting the magnitude of the tracking error to about ± 1 sec, the inventor of the present invention performs feedback control at a frequency of about once per second. I found it necessary. Therefore, it is desirable that the resolution of the red meridian encoder is within about 15 arc seconds.

  On the other hand, even if the inventor of the present invention repeats the feedback control more than about 15 times per second, the inventor cannot expect to greatly increase the tracking error reduction effect. Found that it only increases. Therefore, it is desirable that the resolution of the red meridian encoder is about 1 sec.

  From the above, it is desirable that the resolution of the red meridian encoder is about 1 sec to 15 sec.

  The feedback control in the present invention is not limited to the above example as long as it corrects the angular velocity of the meridian axis using the target value and the measured value of the feedback encoder pulse. As the target value, it is conceivable to use an expected angular velocity, an expected time, etc. in addition to the expected number of clock pulses.

  As an example of another method for comparing the target value and the measured value of the feedback encoder pulse, an average value of a plurality (predetermined number) of feedback encoder pulses may be compared with the target value. For example, the pulse generator 16 temporarily stores the total number of clock pulses of encoder pulses for 100 cycles in the volatile memory. Then, the difference between the value obtained by dividing the total number of clock pulses of encoder pulses for 100 cycles by 100 and the expected number of clock pulses is calculated. Alternatively, the difference between the total number of clock pulses of 100 encoder pulses and 100 times the expected number of clock pulses is calculated. The pulse generator 16 performs such calculation for each cycle. Thereby, the resolution of the encoder can be averaged.

  In this case, the feedback control may not be started immediately after the tracking of the celestial body is started, but the start of the feedback control may be delayed for a predetermined time. For example, when using the average value of encoder pulses for 100 cycles, the time until the pulse generator 16 temporarily stores the total number of clock pulses of encoder pulses for 100 cycles in a volatile memory or the like is feedback controlled. May be delayed.

  Alternatively, an average value of accumulated pulses of feedback encoder pulses from a predetermined timing (for example, the start time of tracking of an astronomical object or the start time of feedback control) may be calculated, and the average value may be compared with a target value. Thereby, the resolution of the encoder can be averaged.

  Furthermore, you may combine both. That is, the average value is calculated using both the average value of a plurality (predetermined number) of feedback encoder pulses and the average value of accumulated pulses from a predetermined timing. And you may compare the average value calculated using both average values, and a measured value. As a result, the resolution of the encoder can be further averaged.

  Further, when the difference between the target value and the measured value is equal to or greater than a predetermined value, an alarm treatment may be performed. Alternatively, instead of performing the alarm treatment (or together with it), a storage unit may be provided for storing the time when the difference becomes a predetermined value or more, equatorial coordinate information of the celestial body, and the like.

  In addition, the automatic celestial tracking device of the first embodiment may be combined with a conventional auto guide device so that the feedback control and the aud guide can be switched.

  Next, Example 2 will be described. Example 2 is an invention for canceling vibrations. FIG. 5 is a conceptual diagram of an astronomical automatic tracking device according to a second embodiment of the present invention. Telescope barrel 1, equatorial mount 2, drive force transmission mechanisms 5, 9, motors 6, 10, motor drivers 7, 11, pulse generators 12, 16, encoders 15, 18, and controller 17 are the same as in the first embodiment. It is a configuration.

  As a result of repeating research and experiments, the inventor of the present invention has found that when the resolution of the encoder is increased to some extent, the encoder pulse behaves repeatedly increasing and decreasing due to the influence of motor vibration and the like. Due to this vibration, the pulse generator 16 may not be able to accurately measure the number of feedback encoder pulses.

  Therefore, in the second embodiment, a vibration cancel circuit is provided between the red meridian encoder 18 and the pulse generator 16 to cancel the increase / decrease in encoder pulses caused by the vibration of the motor and the like, and only the original encoder pulses are pulsed. The configuration is given to the generator 16. The follow-up frequency of the vibration canceling circuit is preferably about 1 MHz or more.

  As a result, even when the encoder pulse increases or decreases due to the influence of motor vibration or the like, the influence can be reduced and the tracking accuracy can be increased.

  A vibration canceling circuit may be provided inside the pulse generator 16. Alternatively, the follow-up frequency of the measurement circuit (not shown) for the number of clocks of the pulse generator 16 may be about 1 MHz or more without providing the vibration cancellation circuit.

  In the second embodiment, the modification described in the first embodiment can also be used.

  Next, Example 3 will be described. The third embodiment is an invention in which the tracking speed of the celestial object is changed based on position information on the equator coordinate of the celestial object to be observed.

  FIG. 6 is a conceptual diagram of the astronomical automatic tracking device of the third embodiment. The telescope barrel 1, the equator 2, the driving force transmission mechanisms 5 and 9, the motors 6 and 10, the motor drivers 7 and 11, and the encoders 14 and 15 are the same as the conventional automatic astronomical tracking device (FIG. 1). is there.

  The operation of this celestial automatic tracking device will be described with reference to FIG. FIG. 7 is a flowchart for explaining an example of the atmospheric difference correction operation of the astronomical automatic tracking device according to the present embodiment.

  First, when tracking of the celestial object is started, the controller 22 calculates the equator coordinate of the celestial object to be observed based on the encoder pulses supplied from the ecliptic axis encoder 14 and the declination axis encoder 15 (S31). ).

  Next, the controller 22 supplies equatorial coordinate information of the celestial body to be observed to the pulse generators 20 and 21 (S32).

  The pulse generators 20 and 21 that have acquired the equatorial coordinate information calculate the tracking speed of the celestial object based on the information (S33). Specifically, the pulse generator 20 calculates the horizon coordinates of the celestial body to be observed based on the equator coordinates of the celestial body to be observed, the longitude / latitude of the observation area, and the observation time, and calculates the atmospheric difference of the horizon coordinates. The rotational angular velocity of the meridian axis 3 taken into consideration is calculated. Similarly, the pulse generator 21 calculates the horizon coordinate of the celestial body to be observed, and calculates the rotation angular velocity of the declination axis 4 in consideration of the atmospheric difference of the horizon coordinate. Any calculation method may be used. For example, a predetermined calculation formula may be used, or a predetermined table or the like may be used.

  Next, each pulse generator 20, 21 supplies a corrected oscillation pulse to each motor driver 7, 11 based on the calculated tracking speed. Thereby, the rotational angular velocities of the red meridian axis 3 and the declination axis 4 are corrected (S34).

  Thereafter, while the tracking of the celestial body is being performed, the celestial body automatic tracking device repeats this atmospheric difference correction (S31 to S34).

  Note that the frequency of calculating the tracking speed in consideration of the atmospheric difference is desirably set to be at least once for about 10 seconds and not more than once for about 1 second. This is because the position of stars changes little in a few seconds from the viewpoint that the atmospheric difference changes.

  In FIG. 7, for convenience of explanation, the tracking speed is calculated (S33) and then the control signal is supplied (S34). However, as an actual process, the tracking speed is calculated. Instead of performing the calculation (S32), a predetermined calculation may be performed based on the supplied equator coordinate information (S32) to immediately supply the corrected oscillation pulse (S34). Even in this case, it is desirable that the frequency of the oscillation pulse correction considering the atmospheric difference correction is set to be at least once in about 10 seconds and not more than once in about 1 second.

  As described above, the astronomical automatic tracking device according to the third embodiment can reduce tracking errors due to atmospheric differences.

  Next, Example 4 will be described. The fourth embodiment is an invention that uses a target value in consideration of an atmospheric difference in feedback control.

  FIG. 8 is a conceptual diagram of the astronomical automatic tracking device of the fourth embodiment. Telescope barrel 1, equatorial mount 2, drive force transmission mechanisms 5, 9, motors 6, 10, motor drivers 7, 11, pulse generator 12, and declination encoder 15 are conventional astronomical automatic tracking devices (FIG. 1). Is the same.

  As in the first and second embodiments, the red meridian encoder 18 has a higher resolution than the conventional one. Specifically, it is desirable that the resolution of the encoder is about 1 sec to 15 sec.

  FIG. 9 is a flowchart illustrating an example of the feedback control operation of the pulse generator 23 according to the fourth embodiment.

  First, as soon as the tracking operation of the celestial body starts, the red longitude axis encoder 18 starts supplying the encoder pulse to the pulse generator 23.

  The pulse generator 23 has a clock pulse generation circuit and a clock pulse number measurement circuit (not shown). As conceptually shown in FIG. 4, the number of clock pulses in one cycle of the feedback encoder pulse supplied to the pulse generator 23. Is measured (S41).

  Next, the pulse generator 23 determines whether or not equatorial coordinate information is supplied from the controller 24 (S42).

  If it is determined in S42 that equator coordinate information is not supplied, the difference between the number of clock pulses in one cycle of the feedback encoder pulse measured in S41 and the expected number of clock pulses is calculated (S44). Thereafter, when there is a difference in the number of pulses, the pulse generator 23 supplies the corrected oscillation pulse to the motor driver 7 (S45).

  On the other hand, if it is determined in S42 that equator coordinate information is supplied, the pulse generator 23 calculates the expected number of clock pulses based on the equator coordinate information (S43). Thereafter, the pulse generator 23 calculates the difference between the number of clock pulses in one cycle of the feedback encoder pulse measured in S41 and the expected number of clock pulses calculated in S44 (S44). Then, when there is a difference in the number of pulses, the pulse generator 23 supplies the corrected oscillation pulse to the motor driver 7 (S45).

  The pulse generator 23 repeats this operation (S41 to S45) while the celestial body is being tracked.

  Thereby, the tracking error can be further reduced.

  Note that the feedback control in the fourth embodiment is not limited to the above example as long as it corrects the angular velocity of the meridian axis using the target value in consideration of the atmospheric difference and the measured value of the feedback encoder pulse.

  For example, the timing for determining whether or not the equatorial coordinate information is supplied and calculating the target value in consideration of the atmospheric difference may be before or after measuring the number of feedback encoder pulses.

  Further, the step of determining whether or not the equator coordinate information is supplied may be omitted. For example, the pulse generator 23 has a memory for storing a target value, and updates the target value stored in the memory each time equator coordinate information is supplied from the controller 24. The pulse generator 23 corrects the angular velocity of the meridian axis using the target value stored in the memory and the measured value of the feedback encoder pulse.

  Further, the frequency of calculating the target value in consideration of the atmospheric difference may be higher, lower, or the same as the frequency of performing the feedback control.

  Note that the vibration canceling configuration described in the second embodiment may be applied to the invention described in the fourth embodiment.

  In addition, the configuration of atmospheric difference correction described in the third embodiment may be applied to the invention described in the fourth embodiment. In this case, the controller 24 and the pulse generator 23 also perform the operations of the controller 22 and the pulse generator 20 in the third embodiment (see FIG. 6), respectively. Further, instead of the pulse generator 12, the pulse generator 21 of the third embodiment (see FIG. 6) is used.

  Needless to say, in the fourth embodiment, the modifications described in the first to third embodiments can be used.

  Finally, the measurement result of the tracking error performed using the astronomical automatic tracking device of Example 2 will be described.

  FIG. 10 shows the measurement results when the tracking error was measured using the astronomical automatic tracking device of Example 2 (the resolution of the red longitude axis encoder is 7.5 sec). The vertical axis represents the magnitude of the tracking error, and the horizontal axis represents the tracking time (measurement time). In order to measure the tracking error, a product called ROD800, Heidenhain, Germany, was used. As a result, it was possible to suppress the tracking error within about ± 1 arc second in the measurement for about 30 minutes. Note that the measurement using this product is not performed while observing actual celestial objects. Therefore, the tracking error due to atmospheric differences is not measured here.

  On the other hand, FIG. 11 shows a measurement result when the tracking error is measured using a conventional automatic astronomical tracking device (the resolution of the red meridian encoder is 7.5 sec). The vertical axis represents the magnitude of the tracking error, and the horizontal axis represents the tracking time (measurement time). Here again, a product called ROD800, Heidenhain, Germany, was used for the measurement.

  As a result of this measurement, the tracking error was about ± 4 arc seconds in the measurement for about 30 minutes.

  As described above, it has become clear from experiments that the tracking error can be reduced by using the present invention.

  Although the present invention is configured as described above, various modifications can be made without departing from the scope of the present invention. For example, the present invention can also be applied to an astronomical auto-tracking device having a graduation platform. In this case, when performing feedback control, it is necessary to correct the angular velocities of the horizontal axis and the altitude axis using feedback encoder pulses of the encoders of the horizontal axis and the altitude axis.

1 Telescope barrel 2 Equatorial mount 3 Axis axis (polar axis)
4 Declination axis 5 Driving force transmission mechanism 6 Inclination motor 7 Motor driver 8 Pulse generator 9 Driving force transmission mechanism 10 Declination motor 11 Motor driver 12 Pulse generator 13 Controller 14 Inclination axis encoder 15 Declination axis encoder 16 Pulse generator 17 Controller 18 Red axis encoder 19 Vibration cancel circuit 20 Pulse generator 21 Pulse generator 22 Controller 23 Pulse generator 24 Controller

Claims (9)

An equatorial mount that supports the telescope barrel in a rotatable manner about two axes of the ecliptic axis and the declination axis ;
A red meridional axis motor for generating a driving force for rotating the telescope barrel about the meridian axis;
A driving force transmission mechanism for transmitting the driving force generated by the red meridian axis motor to the red meridian axis;
A right ascension shaft encoder for detecting the rotation angle of the ascension axis,
A control circuit for controlling the red meridian motor;
The control circuit performs feedback control for reducing tracking errors of the celestial object based on the detected rotation angle of the celestial axis, and performs feedback control for reducing tracking errors of the celestial object. . The control circuit includes:
A driver for supplying a driver signal to the ascension axis motor,
A pulse generator for supplying an oscillation pulse to the driver,
The pulse generator on the basis of the difference between the measured value and the target value of the feedback encoder pulses determined from the detected rotation angle at ascension shaft encoder according to claim 1, characterized in that said feedback control Automatic celestial tracking device. The control circuit includes:
A driver for supplying a driver signal to the red meridian motor;
A pulse generator for supplying an oscillation pulse to the driver,
The pulse generator on the basis of the difference between the average value and the target value of the feedback encoder pulses determined from a plurality of rotation angles detected by the ascension axis encoder, claim 1, characterized in that said feedback control Astronomical object tracking device described in 1. The celestial body automatic tracking device according to any one of claims 1 to 3 , wherein the feedback control is started when a predetermined time has elapsed after the start of tracking operation of the celestial body. The astronomical object tracking device according to any one of claims 1 to 4 , wherein an alarm measure is performed when a difference between a measured value of the feedback encoder pulse and a target value becomes a predetermined value or more. 5 If the difference between the measured value and the target value of the feedback encoder pulses exceeds a predetermined value, the preceding claims, characterized in that it has a memory for storing the equatorial coordinates of the time and / or astronomical at that time The celestial automatic tracking device according to any one of the above. The red resolution via shaft encoder, go-tracking apparatus according to claim 1, wherein 6 to be within 1 5 arcsec least about 1 arcsec. The astronomical automatic tracking device according to any one of claims 1 to 7 , which has a vibration canceling function. A declination axis motor for generating a driving force for rotating the telescope barrel about the declination axis;
A driving force transmission mechanism for transmitting the driving force generated by the declination axis motor to the declination axis;
A declination shaft encoder for detecting the rotation angle of the declination axis,
An equatorial coordinate calculation circuit for calculating an equatorial coordinate of the celestial body to be observed based on the detected rotation angle of the ecliptic axis and the rotation angle of the declination axis;
A horizon coordinate calculation circuit for calculating a horizon coordinate of the celestial body to be observed based on the equator coordinate of the celestial object calculated by the equator coordinate calculation circuit;
The celestial automatic according to any one of claims 2 to 8 , wherein the control circuit sets the target value in consideration of an atmospheric difference of the horizon coordinate calculated by the horizon coordinate calculation circuit. Tracking device.

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