阅读说明：本技术 一种小视场相机天文找北技术方法及装置 (A kind of small field of view camera celestial north-finder technical method and device ) 是由 王海涌 汪博雅 于 2019-08-30 设计创作，主要内容包括：本发明公开了一种小视场相机天文找北技术方法及装置。该装置包括角运动伺服机械平台、小视场相机、辅助设备和控制及信息处理系统。通过控制伺服机械平台做期望的角运动,产生有限个角速度为零的角位置,带动紧固于所述平台的相机做锥扫运动,在平台角速度为零的时刻采集星图从而避免成像拖尾,结合辅助设备提供的信息开展多帧异步星图的处理,计算获得基座平台的姿态及地理北向信息。本发明提供的装置及其操作方法,基于单目小视场相机即可实现全天时姿态确定,大大降低装置的复杂度和体积重量。(The invention discloses a kind of small field of view camera celestial north-finder technical method and devices.The device includes angular movement servounit platform, small field of view camera, ancillary equipment and control and information processing system.Desired angular movement is done by controlling servounit platform, generate the Angle Position that limited angular speed is zero, it drives the camera for being anchored on the platform to do cone and sweeps movement, star chart is acquired at the time of platform angular speed is zero to avoid imaging from trailing, the information provided in conjunction with ancillary equipment carries out the processing of the asynchronous star chart of multiframe, calculates the posture for obtaining base platform and geographical north orientation information.Device provided by the invention and its operating method can be realized round-the-clock posture based on monocular small field of view camera and determine, substantially reduce the complexity and volume weight of device.)

1. a kind of small field of view camera celestial north-finder technical method and device, which is characterized in that described device includes:

One angular movement servounit platform is zero in limited angular position angular speed；

One small field of view camera, is anchored on the angular movement servounit platform, and small field of view camera and the angular movement machinery are flat Platform synchronous follow-up does cone and sweeps movement；

Ancillary equipment, to provide temporal information and local geographic latitude and longitude information；

Control and information processing system, generate the control instruction of angular movement servo mechanism, and carry out the processing of the asynchronous star chart of multiframe, Export posture and north orientation information.

2. the apparatus according to claim 1, which is characterized in that the angular movement servounit platform generates limited angle speed The Angle Position that degree is zero, camera opposed platforms main shaft do cone and sweep movement, and small field of view camera acquires star at the time of angular speed is zero Figure.

3. the operating method of a kind of small field of view camera celestial north-finder technical method and device, which is characterized in that the described method includes:

Step 1, control and information processing system enable servounit platform do desired angular movement, limited angular position occur Angular speed is zero situation；

Step 2, camera optical axis does cone with servounit platform and sweeps movement, camera at the time of servounit platform angular speed is zero Star chart is acquired, asynchronous star chart sequence is obtained；

Step 3, control and information processing system establish the asynchronous star chart of algorithm process multiframe；

Step 4, the temporal information and local geographic latitude and longitude information provided in conjunction with ancillary equipment, calculates the pedestal needed for obtaining Platform stance and geographical north orientation information.

(1) technical field

The invention belongs to astronomical technical fields, are a kind of technical methods and dress that star progress celestial north-finder is seen using camera It sets.

(2) background technique

Celestial north-finder sees star by camera and determines geographical north orientation, is that the novel high-precision non-gyro of one kind looks for northern technology, Have many advantages, such as that strong independence, good concealment, accuracy are high.Big visual field camera Observable star number mesh is more, can be with complete independently appearance State determination and celestial north-finder.However for small field of view camera (such as astronomical telescope), since Observable star number is few (even Lower than 3) and longitudinal axis accuracy of attitude determination it is very low, it is difficult to alone complete starlight determine appearance and celestial north-finder.Daytime celestial north-finder device Small field of view telescope just is needed, is because the ambient level of imaging on small field of view camera daytime is lower, signal-to-noise ratio is higher.Thus solve Small field of view star sensor celestial north-finder technology has important engineering significance.

Some domestic and international mechanisms use three visual field stellar equipments now, and astronomy may be implemented and determine appearance or celestial north-finder. However the equipment of this kind of three visual field or more visual fields (such as: more visual field star sensors or more visual field telescopes), structure is complicated, volume Larger with weight, System Signal Processing difficulty is big.Star number is seen by camera number is increased to make up monocular small field of view camera Purpose is insufficient, is not dexterous design scheme.

(3) summary of the invention

The present invention provides a kind of small field of view camera celestial north-finder technical method and devices, comprising:

One angular movement servounit platform is zero in limited angular position angular speed；

One small field of view camera is anchored on the angular movement servounit platform, the camera optical axis and the platform master The angle of axis is known as semi-cone angle, small field of view camera and the angular movement mechanical platform synchronous follow-up, i.e., the described camera optical axis is opposite Cone, which is done, in the platform main shaft sweeps movement；

Ancillary equipment, to provide temporal information and local geographic latitude and longitude information；

Control and information processing system, generate the control instruction of angular movement servo mechanism, and carry out the asynchronous star chart of multiframe Processing exports posture and north orientation information.

The present invention provides the operating methods of a kind of small field of view camera celestial north-finder technical method and device, include following step It is rapid:

Step 1, control and information processing system enable servounit platform do desired angular movement, make limited angular position Angular speed occur is zero situation；

Step 2, camera optical axis does cone with servounit platform and sweeps movement, in the angle that servounit platform angular speed is zero position Camera acquisition star chart is set, asynchronous star chart sequence is obtained；

Step 3, control and information processing system establish the asynchronous star chart of algorithm process multiframe；

Step 4, the temporal information and local geographic latitude and longitude information provided in conjunction with ancillary equipment, calculates needed for obtaining Base platform posture and geographical north orientation information.

The beneficial effects of the present invention are:

Using angular movement servounit platform, the Angle Position that limited angular speed is zero is generated, when angular speed is zero Acquisition star chart is carved, dynamic imaging is avoided and trails the bottleneck restraining factors of this camera measurement engineering field for many years；Monocular Small field of view camera does cone with servounit platform and sweeps movement, and the round-the-clock of the acquisition asynchronous star chart of multiframe sees star and attitude measurement side Method has dexterously evaded the drawback that the volume weight that three mesh and more mesh celestial navigation unit equipments have is big, system complexity is high.

(4) Detailed description of the invention

Fig. 1 is a kind of schematic diagram of small field of view camera celestial north-finder device.

Number explanation is as follows in figure:

Serial number 1 is angular movement servounit platform.

Serial number 2 is the platform Angle Position that angular speed is zero.

Serial number 3 is small field of view camera.

Serial number 4 is mechanical platform main shaft.

Serial number 5 is small field of view camera optical axis.

Serial number 6 is the Axis Azimuth that cone sweeps the conical surface when acquiring star chart, corresponding with the platform Angle Position that angular speed is zero.

Fig. 2 is small field of view camera celestial north-finder device work flow diagram.

(5) specific embodiment

For a better understanding of the invention, citing is described further a specific embodiment of the invention below.

Using circular dividing table as angular movement servounit platform.Semi-cone angle is set as 20 °, acquires 8 frame star charts, indexing is 45 °, Complete cycle circle amounts to 8 indexing positions.

It then remains static after successively running to each indexing position, acquires star chart, the initial position moment is set as T₁When It carves.Every frame star chart is denoised, the pretreatment such as binaryzation, center coordination, obtains star image mass center as the pixel in plane is sat Mark.Based on the observation star extracted in every frame star chart, finds out star vector under camera measurement system (s system) and be added in observation star library.

It is opposite that post exercise camera is swept according to existing or priori the rough posture information of platform, local geographic latitude and longitude and cone The installation matrix of base platform, can be by the correspondence star vector median filters of each observation star in observation star library to T₁The moment earth is sat Star vector under mark system (e system).With T₁Moment terrestrial coordinate system is referential, then matches, obtain to all observation star vectors Obtain the information such as the corresponding nautical star asterisk of each observation star vector, right ascension declination.

There are following transformational relations for star vector of the nautical star under first point of Aries geocentric inertial coordinate system (i system) and s system:

Then have:

For quiet base platform, transfer matrix of the e system to i systemChange due to earth rotation with observation time, by assisting The temporal information that equipment provides, which calculates, to be obtained, from geographic coordinate system (t system) to the transfer matrix of e systemIt is constant battle array, from platform This system (b system) arrives the transfer matrix of t systemIt is also constant battle array, it can be determining flat from b system to the transfer matrix of e system by solving Platform posture.

It can get the right ascension and declination information of nautical star after successfully completing importance in star map recognition, and then obtain the star vector in i systemIn conjunction withThe value of left side of the equal sign item in formula (2) can be calculatedIt is denoted asAll corresponding one of every nautical star is not WithCamera installs matrixAlso the difference of position is swept and different with known bore, can be calculated, it is different to observe stars pair Answer different vectorsThe calculation formula that star vector is observed under platform body system is as follows:

Based on sequence of vectorsWithCan then be obtained by least square method b system to e system transition matrix

The local geographic logitude λ and geographic latitude provided according to ancillary equipmentT system can be obtained to e system according to formula (4) Transfer matrix

So as to obtain b system to t system transfer matrixThat is attitude matrix:

Therefore course angle ψ, pitching angle theta and the roll angle γ of the available present apparatus.Further according to course angle ψ and base platform Datum level can obtain the real north of platform.