CN103033923B - Tilt correction system based on beacon light detection - Google Patents

Abstract

The invention discloses a tilt correction system based on beacon light detection for eliminating a tracking error of a telescope and improving image stabilization precision, and in particular relates to the telescope, a quick tilting mirror, a beacon light source, a CCD (Charge-Coupled Device) image sensor, a PSD (Phase-Sensitive Detector) and a light splitter. The beacon light source is guided in from a lens cone of the telescope; and through a Kurdish light path in the telescope, beacon light is reflected and projected to a PSD sensor. The position information of an observed object provided by the CCD image sensor is input as a closed loop of the quick tilting mirror; the PSD sensor provides the position information of the beacon light as feedforward control quantity; and the position information is guided in the quick tilting mirror so as to realize the correction system. The system facilitates engineering implementation, and has excellent practicability.

Description

Based on the tilt correction system that beacon beam detects

Technical field

The present invention relates to telescope control field, be specifically related to the tilt correction system that a kind of beacon beam detects, be mainly used in eliminating tracking telescope tracking error, improve image stabilization precision.

Background technology

Telescope generally employ the complex axes control system based on quick slant correction, eliminates telescope tracking error further, improves the observation sharpness of image.Affecting the topmost reason of tilt correction system performance is that the frame frequency of CCD detection system is low, makes the control bandwidth of slant correction inadequate, cannot eliminate the disturbance (such as wind moment, axle system rock) of upper frequency.Although adopt the CCD detection system of high frame rate to add control bandwidth, be reduction of image detection, recognition capability; Secondly, in order to make the reliable and stable work of tilt correction system, multiple CCD detection system generally can be adopted to be placed in same light path, this can make corrective system complicated.

Summary of the invention

The technical problem to be solved in the present invention is: overcome the deficiencies in the prior art, proposes a kind of tilting mirror corrective system detected based on beacon beam.

The technical scheme that the tilt correction system that the present invention is based on beacon beam detection solves the problems of the technologies described above is: described tilt correction system contains beacon light source, PSD sensor, ccd image sensor, spectroscope, tilting mirror, telescope storehouse moral light path and slant correction and control module, wherein

The reflecting surface of spectroscope, tilting mirror relatively and the placement that is parallel to each other; After PSD sensor is positioned at spectroscope; After ccd image sensor is placed on tilting mirror; Beacon light source is arranged on the lens cone for telescope in the moral light path of telescope storehouse, and beacon light source is along with the telescope rotation in the moral light path of telescope storehouse; Beacon light source sends beacon beam after the moral light path of telescope storehouse, through spectroscope, arrives PSD sensor; Target light is after the moral light path of telescope storehouse, and by spectroscope, tilting mirror, reflection arrives ccd image sensor;

Slant correction and control module contain positioner and feedforward controller, PSD sensor as the control information of positioner, and is provided the control information of positional information as feedforward controller of beacon beam by the positional information of the observed object utilizing ccd image sensor to provide; The output of positioner and the output sum of feedforward controller deliver to tilting mirror, just realize tilting mirror closed loop real time correction.

Preferred embodiment: PSD sensor is ccd image sensor, or quadrant sensors.

Preferred embodiment: the beacon beam sent of beacon light source is without tilting mirror, and therefore the motion of tilting mirror can not affect the detection of PSD sensor to beacon beam.

Preferred embodiment: tilting mirror is controlled, wherein:

Follow the tracks of input signal as the input of ccd image sensor, generate position error signal, and as the input of positioner;

Follow the tracks of input signal through PSD sensor, generate the positional information of beacon beam, and as the input of feedforward controller;

Totalizer is used for, to the positional information summation of the target that feedforward controller and positioner export, obtaining control signal; The control signal obtained is utilized to realize tilting mirror closed loop real time correction.

The present invention has relative to the advantage of prior art:

Adopt the sloped correcting method detected based on beacon beam, realize the elimination that telescopical wind moment, axle system are rocked, improve detection accuracy and image quality.

The invention solves prior art adopts the ccd image sensor of high frame rate to add control bandwidth, but is reduction of image detection, recognition capability; Secondly, in order to make the reliable and stable work of tilt correction system adopt multiple CCD detection system to be placed in same light path, the problem of corrective system complexity is made.The present invention is simple, and reliable and stable, Project Realization is easy.

Accompanying drawing explanation

Fig. 1 is light path schematic diagram of the present invention;

Fig. 2 is slant correction and control module structural drawing;

Part numbers explanation

Primary mirror P, secondary mirror M,

First relay lens M1, the second relay lens M2,

3rd relay lens M3, spectroscope M4,

PSD sensor, tilting mirror M5.

Tracking signal input R, tracking signal export Y.

Embodiment

Below in conjunction with the drawings and specific embodiments, the present invention is described, the content that those skilled in the art can disclose according to this instructions understands effect of the present invention and advantage.

As shown in Figure 1, tilt correction system contains described tilt correction system and contains beacon light source L, target light l2, PSD sensor, ccd image sensor, spectroscope M4, tilting mirror M5, telescope storehouse moral light path and slant correction and control module, wherein

The reflecting surface of spectroscope M4, tilting mirror M5 relatively and the placement that is parallel to each other; After PSD sensor is positioned at spectroscope M4; After ccd image sensor is placed on tilting mirror M5; Beacon light source L is arranged on the telescope M lens barrel in the moral light path of telescope storehouse, and beacon light source L rotates along with the telescope M in the moral light path of telescope storehouse; Beacon light source L sends beacon beam l1 after the moral light path of telescope storehouse, through spectroscope M4, arrives PSD sensor; Target light l2 is after the moral light path of telescope storehouse, and by spectroscope M, tilting mirror M5, reflection arrives ccd image sensor;

Slant correction and control module contain positioner and feedforward controller, PSD sensor as the control information of positioner, and is provided the control information of positional information as feedforward controller of beacon beam by the positional information of the observed object utilizing ccd image sensor to provide; The output of positioner and the output sum of feedforward controller deliver to tilting mirror, just realize tilting mirror closed loop real time correction.

Embodiment 1: telescope storehouse moral light path comprises primary mirror P, secondary mirror M, the first relay lens M1, the second relay lens M2, the 3rd relay lens M3, wherein,

The reflecting surface of spectroscope M4, tilting mirror M5 relatively and the placement that is parallel to each other; After PSD sensor is positioned at spectroscope M4; After ccd image sensor is placed on tilting mirror M5; Beacon light source L is arranged on telescopical lens barrel, and beacon light source L rotates along with lens cone for telescope; Beacon light source L send beacon beam l1 through primary mirror P, secondary mirror M in the moral light path of telescope storehouse, relay lens M1, M2 and through spectroscope M3 after, through spectroscope M4, arrive PSD sensor; Target light l2 road after the moral light path of telescope storehouse in primary mirror P, secondary mirror M, relay lens M1, M2 and through spectroscope M3, by spectroscope M4, tilting mirror M5, reflection arrives ccd image sensor.

Further, beacon light source L is fixed on lens cone for telescope, along with lens cone for telescope rotates together.Beacon beam l1 directly enters into PSD sensor by telescope storehouse moral light path through spectroscope M4, and tilting mirror M5, ccd image sensor are successively placed in spectroscope M4 subsequent optical path.Beacon beam is without tilting mirror M5, and therefore the motion of tilting mirror M5 can not affect the detection of PSD sensor to beacon beam.

Further, feedforward controller be feed-forward control signals first through low-pass filter, be then multiplied by that constant realizes.

Beacon light source L is fixed on telescopical lens barrel, and beacon light source L rotates together along with telescopical lens barrel.

Tilting mirror is controlled, wherein:

Follow the tracks of the input signal R input as ccd image sensor, generate position error signal, and as the input of positioner C (s);

Follow the tracks of input signal R through PSD sensor, generate the positional information of beacon beam l1, and as the transport function G of feedforward controller _ffthe input of (s);

Totalizer is used for the transport function G to feedforward controller _ffthe positional information summation of s target that () exports with the transport function C (s) of positioner, obtains control signal; The control signal obtained is utilized to realize tilting mirror M5 closed loop real time correction.

The reflecting surface of primary mirror P and secondary mirror M is staggered relatively, and the first relay lens M1 is between primary mirror P and secondary mirror M, and the reflecting surface of the first relay lens M1 and secondary mirror M is staggered relatively, and primary mirror P receives the beacon beam l1 that beacon light source L sends.

Second relay lens M2 is relative with the reflecting surface of the first relay lens M1 and be parallel to each other and place,

Spectroscope M4 and the 3rd relay lens M3 reflecting surface are that 45 angles are placed respectively with incident beam.Tilting mirror M5 is relative with spectroscope M4 reflecting surface and be parallel to each other and place.

After PSD sensor receiving end is positioned at spectroscope M4 transmission plane, receives beacon beam l1 and convert the positional information of beacon beam to as feed-forward control signals;

Spectroscope M4 is relative with tilting mirror M5 reflecting surface and be parallel to each other and place, and the target surface of ccd image sensor is positioned on the reflecting surface of tilting mirror M5, ccd image sensor receive and positional information echo signal l2 being converted to observed object as position control signal;

Fig. 2 is the control structure figure of the tilt correction system described by Fig. 1, it contains position closed loop and feedforward, concrete is embodied as: the positional information of the observed object R that ccd image sensor provides is as the input of positioner, and PSD sensor provides the input of positional information as feedforward controller of beacon beam; Totalizer produces controller to the output of positioner and the output phase adduction of feedforward controller, delivers to tilting mirror M5, realizes tilting mirror M5 closed loop real time correction.Present problem is exactly the transport function C (s) of how design attitude controller, and the transport function G of feedforward controller _ff(s), specific as follows:

The design of backfeed loop has been very ripe method.The transport function of positioner C (s) can adopt the positioner of ratio+integration (PI) type, and the transport function G of feedforward controller _ffs () is a proportionality constant.It should be noted that after low-pass filtering treatment is had to pass through to disturbance feedforward signal, take advantage of a constant K ₀be incorporated into the input point of position feedback.

G (s) characteristic of the transport function of tilting mirror M5 can regard simple delay link as, the delay of system mainly from process and computing relay, so there is the transport function G (s) of tilting mirror:

G(s)＝e ^-τs(1)

S is Laplace operator, τ is system delay time, general 2 ~ 3 times to the sampling time of ccd image sensor.

The transport function C (s) of positioner is as follows:

$C\left(s\right)=\frac{K_p(T_{i}s+1)}{s}---\left(2\right)$

Wherein, K _p, T _ipositioner gain, integration time constant P, i is-symbol footnote respectively

Can be known by control structure Fig. 2, the present invention to the rejection ability of disturbance is:

$\frac{R}{Y}=\frac{G_{\mathrm{ff}}\left(s\right)G\left(s\right)+1}{C\left(s\right)G\left(s\right)+1}---\left(3\right)$

Formula (1) R is tracking input signal, Y is tracking output signal, and ff is-symbol footnote, can know the transmission letter G when feedforward controller by formula (1) _ff=G ^-1(s).Namely comprise angle position information in feedforward controller, just can eliminate the impact of disturbance completely.Usually when reality uses, feed-forward signal generally can be multiplied by a rate constant K ₀, uncertain for the signal scaling eliminating PSD sensor.In general, the non-constant width of bandwidth of tilting mirror M5, that is transport function G (s) ≈ 1 of tilting mirror M5, the transport function G of feedforward controller _ff(s) ≈-K ₀set up completely in the bandwidth of tilting mirror M5.

If only have FEEDBACK CONTROL (control mode in the past), to the rejection ability of disturbance be:

$\frac{R}{Y}=\frac{1}{C\left(s\right)G\left(s\right)+1}---\left(4\right)$

Relatively validity of the present invention can be known obviously in formula (3), (4).

The part that the present invention does not elaborate belongs to techniques well known.

Although be described the illustrative embodiment of the present invention above; so that the technician of this technology neck understands the present invention; but should be clear; the invention is not restricted to the scope of embodiment; to those skilled in the art; as long as various change to limit and in the spirit and scope of the present invention determined, these changes are apparent, and all innovation and creation utilizing the present invention to conceive are all at the row of protection in appended claim.

Claims (4)

1., based on the tilt correction system that beacon beam detects, it is characterized in that: described tilt correction system contains beacon light source, PSD sensor, ccd image sensor, spectroscope, tilting mirror, telescope storehouse moral light path and slant correction and control module, wherein

The reflecting surface of spectroscope, tilting mirror relatively and the placement that is parallel to each other; After PSD sensor is positioned at spectroscope; After ccd image sensor is placed on tilting mirror; Beacon light source is arranged on the lens cone for telescope in the moral light path of telescope storehouse, and beacon light source is along with the telescope rotation in the moral light path of telescope storehouse; Beacon light source sends beacon beam after the moral light path of telescope storehouse, through spectroscope, arrives PSD sensor; Target light is after the moral light path of telescope storehouse, and by spectroscope, tilting mirror, reflection arrives ccd image sensor;

Slant correction and control module contain positioner and feedforward controller, PSD sensor as the control information of positioner, and is provided the control information of positional information as feedforward controller of beacon beam by the positional information of the observed object utilizing ccd image sensor to provide; The output of positioner and the output sum of feedforward controller deliver to tilting mirror, just realize tilting mirror closed loop real time correction.

2. tilt correction system as claimed in claim 1, is characterized in that: PSD sensor is ccd image sensor, or quadrant sensors.

3. tilt correction system as claimed in claim 1, is characterized in that: the beacon beam that beacon light source L sends is without tilting mirror, and therefore the motion of tilting mirror can not affect the detection of PSD sensor to beacon beam.

4. tilt correction system as claimed in claim 1, is characterized in that: wherein:

Follow the tracks of input signal as the input of ccd image sensor, generate position error signal, and as the input of positioner;

Follow the tracks of input signal through PSD sensor, generate the positional information of beacon beam, and as the input of feedforward controller; Also comprise:

Totalizer is used for, to the positional information summation of the target that feedforward controller and positioner export, obtaining control signal; The control signal obtained is utilized to realize tilting mirror closed loop real time correction.