CN1078703C - Target space position and attitude laser tracking-measuring system and method - Google Patents

Abstract

The present invention belongs to the technical field of laser precise measurement. The system comprises a target reflecting mirror assembly which is composed of more than one reflecting mirror and is fixed on a moving target to be measured, a tracking station group which is composed of more than one tracking station, a laser ranging system, a data acquisition and processing system a real-time feedback control tracking system and software. The present invention adopts a multi-station pure distance method and a single station angle distance method to measure the system through laser tracking to enlarge a range (larger than 120 DEG), of the measurement, and can realize the real-time measurement of the space coordinate, the speed, the acceleration and full allattitude of the moving target.

Description

Object space position and attitude laser tracking measurement system and measuring method thereof

The invention belongs to the accurate laser measurement technical field, the particularly method and system of Laser Tracking moving target locus and attitude measurement design.

The position coordinate-measuring instrument mainly contains three coordinate measuring machine (CMM), electronic theodolite tracking station, total powerstation polar coordinate measurement system and digital camera measurement system in the industry.Their coordinate Calculation principle is respectively: CMM adopts length measurement system directly to export, and electronic theodolite tracking station adopts the space trigonometry, and total powerstation polar coordinate measurement system adopts polar method, and digital pickup system adopts visual transform and coordinate transform.But the measurement range of CMM limited (generally being no more than 2m), the measuring accuracy of electronic theodolite workstation increase with measuring distance and descend, and total powerstation measuring accuracy closely the time is low, and the measuring accuracy of digital pickup system is subjected to the influence of bias light and light source position.And above-mentioned each method is the measurement of static state or utmost point low speed.Therefore, geometric sense metrology and measurement worker active research laser tracking measurement system both domestic and external in recent years is to measure the position coordinates of moving target.Usually adopt laser interferance method and triangulation technology at present.This method adopts laser as light source, settles optical mirror on measured target, by laser beam incessantly tracking mirror measure the position coordinates of measured target in real time.

Research for moving object attitude measurement in the industrial circle, the attitude that at present only limits to demarcate the robot terminal actuator basically, and traditional attitude measurement means require robot to be under static state or the motion state than low speed, adopt the attitude of a plurality of length measurement sensors (clock gauge) static demarcating robot arm, recently the someone adopts vision CCD initiatively to videotape the attitude that method is measured moving target, adopt a tracking station, use corner cube as target mirror, and calculate target attitude by the angle between three ribs of CCD camera device measurement corner cube.Because effective operating angle of corner cube is less than ± 20 °, the switching rate of CCD device is lower, so hangs down the attitude measurement of precision in can only being applicable among a small circle, than low speed.

The objective of the invention is to for overcoming the weak point of traditional location and attitude measuring, a kind of object space position and attitude laser tracking measurement system and measuring method thereof are proposed, the volume coordinate of three-dimensional motion target that pure Furthest Neighbor of employing multistation and list have been stood angular distance method difference tracking measurement.Make the expanded range (greater than 120 °) of measuring object, and can realize the real-time measurement of rapid movement object space position, speed, acceleration and full attitude.

The present invention proposes the laser tracking measurement system of a kind of moving target locus and attitude, the tracking station and the laser distance measuring system that is installed on it and computer control that links to each other with tracking station and the data acquisition processing system that comprise target mirror, be made up of two-dimentional servo tracking system, photodetector system, FEEDBACK CONTROL tracker; It is characterized in that, the composite object reflector group that said target mirror is made up of an above catoptron that is fixed on the tested moving target, each catoptron distributes by the certain space position relation that is suitable for attitude measurement; The tracking station group of said tracking station for constituting by an above tracking station; Said computer control and data acquisition processing system comprise computing machine and interface and change-over circuit, and are stored in tracking control algorithm software, measured target CALCULATION OF PARAMETERS software in the said computing machine.

The said composite object reflector group of the present invention can be by one or more combinations of the reflex reflection mirror of types such as plane mirror, solid corner cube, retroreflector or " opal " catoptron.

Said laser distance measuring system can be a kind of of laser double frequency linear measure longimetry interferometer, laser range finder, absolute distance laser range finder; Its emergent ray and incident ray are gone the same way or the constant offset amount are arranged.

Said two-dimentional servo tracking system can comprise and follow the tracks of pedestal, tracking lens and drive executive component; Vertical, the quadrature or non-orthogonal of tracking pedestal diaxon; The scrambler of the corner of measuring shaft in real time is installed on the axle; Drive rubbing property mechanism a kind of that executive component can be DC servo motor, AC servo motor, step-servo motor or other type, said tracking lens is installed on the diaxon rotation track frame, driving tracking lens by track frame rotatablely moves as two dimension, said driving executive component, be contained in and follow the tracks of on the pedestal, drive and follow the tracks of the pedestal rotation.

Said photodetector system can comprise optical beam splitting device, photodetector and photoelectric switching circuit; This photodetector adopts a kind of of CCD, four-quadrant photocell or PSD device; The segment beam that is returned by target mirror converts electric signal to by the photodetector reception and by photoelectric switching circuit behind optical element.The transmitance of this optical beam splitting device and reflectivity can have various inverse ratios.

Said FEEDBACK CONTROL tracker can comprise control circuit, power amplification circuit and holding circuit thereof through the hardware of circuit connection; The control circuit of this hardware can comprise the feedback that tests the speed, position feedback and current feedback circuit, perhaps their combination; The photodetector output signal is sent into the FEEDBACK CONTROL tracker through processing and amplifying, produces deviation signal and drive signal, does two dimension by driving executive components such as interface drive motor and rotatablely moves.

Said interface and change-over circuit can comprise hardware interface circuit, A/D converter and the D/A converter of parallel or serial.

Said tracking control algorithm software can adopt traditional analog or digital pid control algorithm, adaptive prediction control algolithm or fuzzy logic control algorithm to work out.

The present invention proposes a kind of measuring method that adopts said system, it is characterized in that comprising: measurement two parts of the tracking of target and targeted attitude, and said target following is made up of following steps:

(1) the target mirror group is rigidly secured on the measurand, and drives the corresponding motion of do by measurand;

(2) the target mirror group is placed in the tracking spatial dimension of tracker, when target was static, the error output signal of artificially adjusting Photodetection system was zero, and followed the tracks of and go up target; Tracker is operated under the search pattern, seeks target automatically;

(3) after system finds target, controller drives servo-drive system and does to follow the tracks of accordingly to rotatablely move according to the size and Orientation of error signal;

(4) when track rejection, target mirror is got back to initial position, or is begun by new position, by target on the system keeps track;

The measurement of said targeted attitude is made up of following steps:

(5) calibrate geometric position size between the target mirror in advance;

(6) position that calibrates in advance between each tracking station concerns, comprises that coordinate, the transformation relation between each tracking station's coordinate system and each tracking station between each tracking station arrive the initial distance of target;

(7) tracking station measures angle or the range information of corresponding target at sampled point, calculate the coordinate of target, and with coordinate conversion under the same coordinate system, revise various measuring error after, calculate the attitude of target under main website coordinate system and target self coordinate system respectively.

Coordinate is measured by said tracking station can adopt angle-Furthest Neighbor: comprise that each tracking station measures rotation angle and tracking station's range-to-go value of rich two vertical axis of tracking lens respectively, utilize polar method to calculate the coordinate of target, pass through homogeneous coordinate transformation again, the data-switching of each tracking station under the same coordinate system, and is calculated target attitude.

Coordinate is measured by said tracking station also can adopt pure Furthest Neighbor: comprise each tracking station only measurement target to the variable in distance amount of tracking station, pass through Redundancy Design, with the geometric parameter that calculates system from standardization, by the measuring point redundancy, the objective definition evaluation function is tried to achieve the coordinate of target by resolving Nonlinear System of Equations, uses coordinate transform again, measurement data is connected, and calculate the attitude of target under different coordinates.

Measuring principle of the present invention is as follows:

The a plurality of target mirror combinations of tracking measurement respectively of a plurality of tracking stations, measuring system adopts polar method and polygon method to calculate the coordinate of target respectively, define different coordinate systems, and employing homogeneous coordinate transformation, realize the conversion between different tracking stations coordinate system, calculate the attitude of target under different coordinates then.

The laser beam that ranging laser sends is mapped to parallel returning behind the measured target catoptron, be divided into two bundles through behind the beam splitter, a branch of reference signal stack as measuring-signal and interferometer, the variable in distance amount of measurement target, another Shu Guang is reflected on the position sensor, as tracking error signal, Control Servo System rotatablely moves accordingly.

Adopt angular distance method tracing measurement system, utilize polar method to calculate coordinates of targets, need to measure the corner of rich two vertical rotating shafts of tracking lens and target distance (demarcating initial distance in advance) to the tracking station center; Adopt pure Furthest Neighbor tracing measurement system, utilize polygon method to calculate the coordinate of target, only measure tracking station's center range-to-go (from demarcating the position of initial distance and tracking station, being defined as the demarcation certainly of system's geometric parameter in advance).After calculating the position coordinates of target, speed, the acceleration that can be calculated target by kinematic relation are respectively $v_i=\frac{X_i\left(t\right)-X_{i-l}\left(t\right)}{\mathrm{\ΔT}}$ $a_1=\frac{v_i\left(t\right)-v_{i-1}\left(t\right)}{\mathrm{\ΔT}}=\frac{X_i\left(t\right)-2X_{i-1}\left(t\right)+X_{i-2}\left(t\right)}{{\mathrm{\ΔT}}^2}-----\left(1\right)$

X _i(t) be the coordinate of target, v _iAnd a _iBe respectively the instantaneous velocity and the acceleration of target, Δ T is a sampling time interval.

Need to adopt coordinate transform between different tracking stations coordinate system, the data between tracking station are connected, and under different coordinate systems, calculate target attitude respectively.

The present invention has following characteristics:

The one, target mirror adopts array configuration, places on the tested motion object, and the position between them rigidly fixes, and is guaranteed by process.Target mirror can return device for various optics are contrary, can be plane mirror, solid corner cube, retroreflector or " opal " catoptron etc.

The number of the 2nd, tracking station is a plurality of, and the corresponding angle Furthest Neighbor adopts three tracking stations, and corresponding pure apart from rule employing six or eight tracking stations.

The 3rd. corresponding different tracking stations has defined main website, extension station and target-based coordinate system.Need to carry out coordinate transform between different coordinates, coordinate transform obtains by the measurement data of tracker self, and need be by external material standard chi.

The 4th. the coordinate of target can be obtained by polar method or polygon method, is measuring the speed and the acceleration that can further calculate target on the basis of coordinates of targets.Data-switching between different coordinates under the main website coordinate system, can be calculated the attitude of target under main website coordinate system and self coordinate system respectively.

The 5th. system can be operated in search pattern and tracking measurement pattern.

Measurement range of the present invention can reach 0.1 meter to 30 meters, and target velocity can reach 1m/s, and the acceleration of target can reach 3g.And method of coordinates transform between the different tracking stations has been proposed, set up targeted attitude calculation mathematic model under the different coordinates.Measuring system can be used for the initial attitude monitoring of space tracking, rocket launching of the motion parts on robot actuator (end effect device), the heavy duty machine tools, novel target axle machine tooling cutter and demarcation etc.

Brief Description Of Drawings: Fig. 1 is an embodiment of the present invention angular distance genealogy of law system pie graph.Fig. 2 is the index path of this implementation system.Fig. 3 changes synoptic diagram between the present embodiment coordinate system.Fig. 4 is the tracking measurement method flow diagram of present embodiment.Fig. 5 is the pure Furthest Neighbor of the another kind of embodiment of the present invention system pie graph.When Fig. 6 is the pure Furthest Neighbor tracking measurement of present embodiment, definite method synoptic diagram of coordinates of targets.

The present invention proposes the laser tracking measurement method and system embodiment of a kind of moving target locus and attitude, is described in detail as follows in conjunction with the formation and the measuring method of Fig. 1～6 pair system:

Fig. 1 is a kind of formation synoptic diagram of present embodiment system, adopt the angular distance method, measuring system is made up of following several parts: 1. the target mirror combination 4, be three plane mirror A, B, C, also can be various types of converse devices such as solid axle corner prism, retroreflector or " opal " catoptron.Close mutual alignment between them is to be rigidly connected, and is accurately guaranteed by process.2. the system of tracking station comprises three tracking stations 1,2,3 that structure is identical, and the principle that coordinate is measured by tracking station is a polar method.3. each tracking station is made up of two-dimentional servo tracking system, photodetector system, FEEDBACK CONTROL tracker; Said two-dimentional servo tracking system comprises and follows the tracks of pedestal, tracking lens and drive executive component; Vertical, the quadrature/non-orthogonal of tracking pedestal diaxon; The scrambler of the corner of measuring shaft in real time is installed on the axle; The rubbing property mechanism that this driving executive component is DC servo motor, AC servo motor, step-servo motor or other type a kind of, said tracking lens is installed on the diaxon rotation track frame, driving tracking lens by track frame rotatablely moves as two dimension, said driving executive component, be contained in and follow the tracks of on the pedestal, drive and follow the tracks of the pedestal rotation.Said two-dimentional servo tracking system can realize following the tracks of and measuring this two functions simultaneously; Realize following function, need tracking servo, optical system, Photoelectric Signal Processing system, Tracking Control Software; Realize measurement function, need two angular measurement sensors and a length measurement sensor, angular measurement sensor adopts high-precision scrambler (resolution is better than 1 rad), and length measurement sensor adopts two-frequency laser interferometer (requiring measuring speed fast, for example HP5529 or product of the same type).

4. computer control and data acquisition processing system.Comprise various interface and change-over circuit, and the algorithm software that calculates the measured target parameter.Coordinate transformation algorithm between coordinate system is seen Fig. 3, and the algorithm of object space position and attitude is as follows: the computing method of targeted attitude under (1) main website coordinate system

Three tracking measurement stations 1,2,3 are tracking measurement A, B, three catoptrons of C coordinate in measuring system separately in real time respectively.Trace point B that measuring station 2 and 3 records respectively and the coordinate of C are based on the coordinate of they self extension station coordinate system, need through homogeneous transformation to obtain the coordinate under the main website coordinate.Just can calculate target attitude according to A, B, the coordinate of C under the main website coordinate system. $\sin$ ${\mathrm{\&beta;}}_i=-u_{zi},\cos {\mathrm{\&beta;}}_i=\&PlusMinus;\sqrt{1-u_{zi}^2}-----\left(2\right)$ $\sin a_i=\&PlusMinus;\frac{v_{2i}}{\sqrt{1-u_{zi}^2}},\cos a_i=\&PlusMinus;\frac{w_{2i}}{\sqrt{1-u_{zi}^2}}-----\left(3\right)$ $\sin {\mathrm{\&gamma;}}_i=\&PlusMinus;\frac{u_{\mathrm{yi}}}{\sqrt{1-u_{\mathrm{<figure-callout\; id="2"\; label="zi"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">zi</figure-callout>}}^2}},\cos {\mathrm{\&gamma;}}_i=\&PlusMinus;\frac{u_x}{\sqrt{1-u_{\mathrm{zii}}^2}}-----\left(4\right)$ In measuring process, 0 °≤α of definition, beta, gamma≤180 °, α like this _i, β _i, γ _iJust can uniquely determine.Then the full attitude of target under the main website coordinate system is (x _Li, y _Li, z _Li, α _i, β _i, γ _i), i is each measuring position.(2) target attitude computation process under the target-based coordinate system

At first need the homogeneous transformation matrix T between definite target-based coordinate system and main website coordinate system _{0 → 0 '}, calculate the coordinate of target under target-based coordinate system.In order to calculate that the main website coordinate is tied to the transformation matrix T of target-based coordinate system _{0 → 0 '}, done as giving a definition, as shown in Figure 1. ${\stackrel{\&RightArrow;}{r}}_{1w}=\stackrel{\&RightArrow;}{\mathrm{OA}}$ ${\stackrel{\&RightArrow;}{r}}_{1t}=\stackrel{\&RightArrow;}{O^{\&prime;}A}=\stackrel{\&RightArrow;}{O}$ ${\stackrel{\&RightArrow;}{r}}_{2w}=\stackrel{\&RightArrow;}{\mathrm{OB}}$ ${\stackrel{\&RightArrow;}{r}}_{2t}=\stackrel{\&RightArrow;}{O^{\&prime;}B}=\stackrel{\&RightArrow;}{\mathrm{AB}}$ ${\stackrel{\&RightArrow;}{r}}_{3w}=\stackrel{\&RightArrow;}{\mathrm{OC}}$ ${\stackrel{\&RightArrow;}{r}}_{3t}=\stackrel{\&RightArrow;}{O^{\&prime;}C}=\stackrel{\&RightArrow;}{\mathrm{AC}}$ ${\stackrel{\&RightArrow;}{r}}_{4w}=({\stackrel{\&RightArrow;}{r}}_{2w}-{\stackrel{\&RightArrow;}{r}}_{1w})\&times;({\stackrel{\&RightArrow;}{r}}_{3w}-{\stackrel{\&RightArrow;}{r}}_{1w})+{\stackrel{\&RightArrow;}{r}}_{1w}$ ${\stackrel{\&RightArrow;}{r}}_{4t}=({\stackrel{\&RightArrow;}{r}}_{2t}-{\stackrel{\&RightArrow;}{r}}_{1t})\&times;({\stackrel{\&RightArrow;}{r}}_{3t}-{\stackrel{\&RightArrow;}{r}}_{1t})+{\stackrel{\&RightArrow;}{r}}_{1t}$ Then be tied to form upright just like ShiShimonoseki: $\&lsqb;{\stackrel{\&RightArrow;}{r}}_{1t},{\stackrel{\&RightArrow;}{r}}_{2t},{\stackrel{\&RightArrow;}{r}}_{3t},{\stackrel{\&RightArrow;}{r}}_{4t}\&rsqb;=T_{O\&RightArrow;O^{\&prime;}}\&lsqb;{\stackrel{\&RightArrow;}{r}}_{1w},{\stackrel{\&RightArrow;}{r}}_{2w},{\stackrel{\&RightArrow;}{r}}_{3w},{\stackrel{\&RightArrow;}{r}}_{4w}\&rsqb;-----\left(5\right)$ Find the solution: $T_{O\&RightArrow;O^{\&prime;}}={\&lsqb;{\stackrel{\&RightArrow;}{r}}_{1t},{\stackrel{\&RightArrow;}{r}}_{2t},{\stackrel{\&RightArrow;}{r}}_{3t},{\stackrel{\&RightArrow;}{r}}_{4t}\&rsqb;\&lsqb;{\stackrel{\&RightArrow;}{r}}_{1w},{\stackrel{\&RightArrow;}{r}}_{2w},{\stackrel{\&RightArrow;}{r}}_{3w},{\stackrel{\&RightArrow;}{r}}_{4w}\&rsqb;}^{-1}-----\left(6\right)$ Three the coordinate (xs of sub-goal under the main website coordinate system then _Ji, y _Ji, z _Ji) and target-based coordinate system under coordinate (x ' _Ji, y ' _Ji, z ' _Ji) between have a following transformation relation: $\left[\begin{array}{c}{x}_{\mathrm{ji}}^{\&prime;}\\ y_{\mathrm{ji}}^{\&prime;}\\ z_{\mathrm{ji}}^{\&prime;}\\ 1\end{array}\right]=T_{O\&RightArrow;O^{\&prime;}}\left[\begin{array}{c}{x}_{\mathrm{ji}}\\ y_{\mathrm{ji}}\\ z_{\mathrm{ji}}\\ 1\end{array}\right]-----\left(7\right)$ In the formula, j=1,2,3, expression A, B, C three sub-goals; I=1,2 ..., n represents to measure the employing point.Method with formula (2) to (4) is calculated three the rotational coordinates αs of target in target-based coordinate system _i', β _i' and γ _i'.Answer the coordinate figure of substitution each point under target-based coordinate system during calculating.Can get the targeted attitude coordinate under the target-based coordinate system like this: (x _Li', y _Li', z _Li', α _i', β _i', γ _i').Can be compiled into computer software by said method and calculate the targeted attitude coordinate.

Fig. 2 is the light path principle figure of a tracking station.Among the figure, frame of broken lines 5 is a two-frequency laser interferometer, it be light source be again length measurement sensor.Light beam is divided into two bundles after by polarization splitting prism 6, and a branch of interferometer of getting back to is as reference signal (f ₁), a branch of by beam splitter 7 back (f ₂), be fixed on tracking lens 8 reflections that drive on the executive component, the target mirror 9 back parallel beams that directive is installed on the measured target return, the tracked mirror of Returning beam is reflection again, by being divided into two bundles behind the beam splitter, a branch of light is got back to interferometer as distance measurement signals, and a branch of in addition smooth directive position sensitive detector (PSD) 10 generates the tracking Control error signal.When target travel, corresponding mobile takes place in the position of the light beam that returns on detector, detector circuit is measured the offset error signal in real time, be used for the motor of control drive unit 11, adjust the corner of tracking lens, make the geometric center of the facula position trend detector on the detector, keep the tracking error minimum.

Fig. 3 is the coordinate system transformation principle schematic of embodiment.Among the figure, convenient for call for Votes, only analyze the method for determining transformation matrix between two measurement coordinate system, a plurality of tracking stations realize coordinate transformation method similarly.Measurement coordinate system { the o of tracking station 1 ₁x ₁y ₁z ₁Be defined as main website coordinate system, the measurement coordinate system { o of tracking station 2 ₂x ₂y ₂z ₂Being defined as the extension station coordinate system, two tracking stations follow the tracks of same target P simultaneously, and measure the volume coordinate of P under coordinate system separately respectively and be { m _iAnd { d _i, i=1,2 ..., n is counting of sampled measurements target.So, { m _iAnd { d _iPoint between exist one to one that transformation relation is: $\left[\begin{array}{c}{\mathrm{<figure-callout\; id="1"\; label="d\; i"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">d</figure-callout>}}_i\\ 1\end{array}\right]=\left[\begin{array}{cc}R& T\\ 0& 1\end{array}\right]\left[\begin{array}{c}{m}_i\\ 1\end{array}\right]+\left[\begin{array}{c}{V}_i\\ 0\end{array}\right]-----\left(8\right)$ In the formula, mark Be respectively target P at the coordinate system O of main website ₁, the coordinate system O of extension station ₂Under seat, V _iBe 3 * 1 noise vectors, R is 3 * 3 rotational transform orthogonal matrix, its determinant of a matrix be on the occasion of, T is 3 * 1 translation vector.By select measuring redundant points, separate the least squares equation group, make the quadratic sum minimum of residual error determine unknown number in the transformation matrix.That is: ${\mathrm{\&epsiv;}}^2=\underset{i=1}{\overset{N}{\mathrm{\&Sigma;}}}\left|\right|d_i-{\hat{R}m}_1-\hat{T}\left|\right|$

Be respectively the optimum solution of rotational transform matrix R and translation transformation vector T.Formula (9) is a nonlinear least square journey group, and we propose, and when the movement locus of target is space path, and tracking station's measuring error hour, adopts the decomposition of singular matrix method to find the solution; And, adopt the hypercomplex number method to find the solution when the movement locus of target during on same plane or the measuring error of tracking station when big.

Fig. 4 is the tracking measurement method flow of present embodiment.

By flowing to computing machine after the A/D converter sampling, computing machine is controlled rotatablely moving of motor according to the size and Orientation of magnitude of voltage to the two paths of signals of detector output respectively.The control algolithm flow process of computer-internal is mainly by following several parts:

1) initial parameter is set: port address, control signal threshold voltage, drive motor initial position and the target of setting A/D, D/A are to tracking station's initial distance value.

2) the drive motor working method is judged: judge according to four tunnel sum voltages signals whether hot spot drops on the photosurface of detector PSD.When hot spot is positioned on the detector, the sum voltages signal is provided with drive motor and is operated in tracking mode much larger than threshold voltage; And outside hot spot is positioned at detector the time, the sum voltages signal is provided with drive motor and is operated in search condition less than threshold voltage.

3) target search: if sum voltages, is set machine operation less than threshold voltage at the search sweep state.Put Y earlier and be still in fixing position to drive motor, X scans gamut to motor, and controlling Y then increases fixed step size to motor, allows X omnidistance to motor scanning again.Gather sum voltages in the scanning process in real time, judge facula position.When judging hot spot and be positioned on the detector, redirect drive motor working method is a tracking mode.

4) target following: when sum voltages during greater than threshold voltage, A/D converter is gathered X and Y respectively to differential voltage, compares with threshold voltage.If differential voltage greater than threshold voltage, is controlled the corner of corresponding motor respectively and turned to, realize tracing task.

5) coordinate Calculation, according to interferometer reading and motor corner, the volume coordinate formula that calculates target is:

In the formula, R is the distance of target to tracking station, and α, β are respectively the corner of Z-axis and horizontal shaft electric machine.

6) targeted attitude calculates.Other tracking station's data-switching under the main website coordinate system, is calculated target at the attitude under the main website coordinate system and the target coordinate under self coordinate system by formula (2)～(4).When measuring in real time, just can calculate instantaneous speed and acceleration by the position and time interval of each measuring point.

Fig. 5 is that the another kind of present embodiment system constitutes synoptic diagram, adopts the full attitude of pure Furthest Neighbor measurement target, and system is made up of following several parts: 1. target mirror system, and with shown in Figure 1.2. the system of tracking station adopts six tracking stations, and each tracking station's structure does not just have angular measurement sensor with angular distance method system similarity.3. adopt three station 12,13,14 tracking target catoptron A, two 15,16 tracking target catoptron B of tracking station, the 17 tracking target catoptron C of tracking station, measure the coordinate of target mirror under corresponding tracking station respectively, be transformed under the main website coordinate system, utilize formula (2)～(4) to calculate target attitude.

When Fig. 6 is the pure Furthest Neighbor tracking measurement of present embodiment, definite method of coordinates of targets:

Calibrate the spatial relation of each tracking station in advance and to the initial distance of target, three tracking stations and target can constitute a tetrahedron in the space, as shown in Figure 6.Tetrahedron PZ ₁Z ₂Z ₃In, Z ₁, Z ₂, Z ₃Represent three tracking stations respectively, O is the intersection point of summit to the bottom surface, and M is Z ₃To Z ₁Z ₂Make the intersection point of vertical line, O ₁And M ₁Be respectively O to Z ₃M and Z ₁Z ₂Make the intersection point of vertical line, P is a target, is positioned at tessarace, and its coordinate can be represented by the geometric parameter of system.The coordinate of target P is:

In the formula | PM ₁|, | PM|, | Z ₃M ₁| be respectively: $\left|Z_1{\mathrm{<figure-callout\; id="1"\; label="M"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">M</figure-callout>}}_1\right|=\frac{{\left|Z_1{\mathrm{<figure-callout\; id="3"\; label="Z"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">Z</figure-callout>}}_3\right|}^2-{\left|Z_2{\mathrm{<figure-callout\; id="3"\; label="Z"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">Z</figure-callout>}}_3\right|}^2+{\left|Z_1{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2\right|}^2}{2\left|Z_1{\mathrm{<figure-callout\; id="2"\; label="Z"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">Z</figure-callout>}}_2\right|}$ $\left|\mathrm{<figure-callout\; id="1"\; label="P\; M"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">P</figure-callout>}{M}_{}{}_1\right|=\sqrt{{\left|\mathrm{<figure-callout\; id="1"\; label="P\; Z"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">P</figure-callout>}{Z}_{}{}_1\right|}^2-x^2}$ $\left|Z_{3}M\right|=\sqrt{{\left|Z_1{\mathrm{<figure-callout\; id="3"\; label="Z"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">Z</figure-callout>}}_3\right|}^2-{\left|Z_{1}M\right|}^2}-----\left(12\right)$ $\left|\mathrm{PM}\right|=\sqrt{{\left|{\mathrm{<figure-callout\; id="1"\; label="PM"\; filenames="C9910962300131.png"\; state="\{\{state\}\}">PM</figure-callout>}}_1\right|}^2+{\left(\right|Z_{1}M|-x)}^2}$

It is pointed out that and adopt the tetrahedron length of side to determine apex coordinate that can obtain two groups of data in theory, promptly summit P and summit are about tetrahedron bottom surface (Z ₁Z ₂Z ₃) symmetric points P ' (not drawing among the figure), these 2 only the z graticule ticks is opposite on mathematic(al) representation.Therefore, need to judge the symbol of z in the calculation procedure, be easy to generally speaking determine that by the range of movement of reference frame and target formula has been got positive sign in (10).

The foregoing description system installation set-up procedure is as follows:

1. the target mirror combination is rigidly secured on the measurand, and drives the corresponding motion of do by measurand;

2. the target mirror combination is placed in the working field of view scope of tracker, can be when target to be static, the error output signal of artificially adjusting Photodetection system is zero, also can make certain way of search by computer control system, seeks target; After system found target, controller drove servo-drive system and rotatablely moves accordingly according to the size and Orientation of error signal;

3. when track rejection, target mirror is got back to initial position, or is begun by new position, by target on the system keeps track;

4. calibrate the physical dimension size between the target mirror in advance, this is finished by the processing design process;

5. calibrate the position relation between the tracking station in advance, comprise that coordinate, the conversion between tracking station's coordinate system and tracking station between tracking station arrive the initial distance of target;

6. tracking station measures angle or the range information of corresponding target at sampled point, calculates the coordinate of target, and with coordinate conversion under the same coordinate system;

7. calculate the attitude of target under main website coordinate system and target self coordinate system respectively, and revise various measuring error.

Claims (10)

1. the laser tracking measurement system of moving target locus and attitude, the tracking station and the laser distance measuring system that is installed on it and computer control that links to each other with tracking station and the data acquisition processing system that comprise target mirror, formed by two-dimentional servo tracking system, photodetector system, FEEDBACK CONTROL tracker; It is characterized in that, the composite object reflector group that said target mirror is made up of an above catoptron that is fixed on the tested moving target, each catoptron distributes by the certain space position relation that is suitable for attitude measurement; The tracking station group of said tracking station for constituting by an above tracking station; Said computer control and data acquisition processing system comprise computing machine and interface and change-over circuit, and are stored in tracking control algorithm software, measured target CALCULATION OF PARAMETERS software in the said computing machine.

2. measuring system as claimed in claim 1 is characterized in that, said composite object reflector group is by a kind of combination among the reflex reflection mirror of plane mirror, solid corner cube, retroreflector " opal " mirror type.

3. measuring system as claimed in claim 1 is characterized in that, said two-dimentional servo tracking system comprises and follows the tracks of pedestal, tracking lens and drive executive component; Vertical, the quadrature/non-orthogonal of tracking pedestal diaxon; The scrambler of the corner of measuring shaft in real time is installed on the axle; The rubbing property mechanism that this driving executive component is DC servo motor, AC servo motor, step-servo motor or other type a kind of, said tracking lens is installed on the diaxon rotation track frame, driving tracking lens by track frame rotatablely moves as two dimension, said driving executive component, be contained in and follow the tracks of on the pedestal, drive and follow the tracks of the pedestal rotation.

4. measuring system as claimed in claim 1 is characterized in that, said photodetector system comprises optical beam splitting device, photodetector and photoelectric switching circuit; This photodetector adopts a kind of of CCD, four-quadrant photocell or PSD device; The segment beam that is returned by target mirror converts electric signal to by the photodetector reception and by photoelectric switching circuit behind optical element.

5. measuring system as claimed in claim 1 is characterized in that, said FEEDBACK CONTROL tracker comprises control circuit, power amplification circuit and holding circuit thereof through the hardware of circuit connection; The control circuit of this hardware comprises the feedback that tests the speed, position feedback and current feedback circuit.

6. measuring system as claimed in claim 1 is characterized in that, said interface and change-over circuit comprise hardware interface circuit, A/D converter and the D/A converter of parallel or serial.

7. measuring system as claimed in claim 1 is characterized in that, said tracking control algorithm software adopts traditional analog or digital pid control algorithm, adaptive prediction control algolithm or fuzzy logic control algorithm to work out.

8. a measuring method that is used for the described system of claim 1 is characterized in that, comprising: measurement two parts of the tracking of target and targeted attitude, and said target following is made up of following steps:

(1) the target mirror group is rigidly secured on the measurand, and drives the corresponding motion of do by measurand;

(2) the target mirror group is placed in the tracking spatial dimension of tracker, when target was static, the error output signal of artificially adjusting Photodetection system was zero, and followed the tracks of and go up target; Tracker is operated under the search pattern, seeks target automatically;

(3) after system finds target, controller drives servo-drive system and does to follow the tracks of accordingly to rotatablely move according to the size and Orientation of error signal;

(4) when track rejection, target mirror is got back to initial position, or is begun by new position, by target on the system keeps track;

The measurement of said targeted attitude is made up of following steps:

(5) calibrate geometric position size between the target mirror in advance;

(6) position that calibrates in advance between each tracking station concerns, comprises that coordinate, the transformation relation between each tracking station's coordinate system and each tracking station between each tracking station arrive the initial distance of target;

(7) tracking station measures angle or the range information of corresponding target at sampled point, calculate the coordinate of target, and with coordinate conversion under the same coordinate system, revise various measuring error after, calculate the attitude of target under main website coordinate system and target self coordinate system respectively.

9. measuring method as claimed in claim 9, it is characterized in that, said tracking station measures coordinate and adopts angle-Furthest Neighbor: comprise that each tracking station measures rotation angle and the tracking station range-to-go value of tracking lens around two vertical axis respectively, utilize polar method to calculate the coordinate of target, pass through homogeneous coordinate transformation again, the data-switching of each tracking station under the same coordinate system, and is calculated target attitude.

10. measuring method as claimed in claim 9, it is characterized in that, said tracking station measures coordinate and adopts pure Furthest Neighbor: comprise each tracking station only measurement target by Redundancy Design, use the geometric parameter of the system that calculates from standardization to the variable in distance amount of tracking station, by the measuring point redundancy, the objective definition evaluation function is tried to achieve the coordinate of target by resolving Nonlinear System of Equations, uses coordinate transform again, measurement data is connected, and calculate the attitude of target under different coordinates.

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