SU1536204A1 - Device for determining position and orienting an object - Google Patents

Abstract

This invention relates to instrumentation technology. The purpose of the invention is to increase the information content by determining six coordinates determining the position and orientation of an object in space, improving accuracy by providing small angular divergence of the scanning beam and discreteness of reading information about its position, increasing reliability by eliminating the influence of pulsed light interference from outsiders. sources and increased resolution by reducing the effect of background light interference. The collimating lens 5, mounted in the hollow shaft 3 of the scanning mechanism 2 with transverse displacement relative to the focusing lens 4, forms together with it a telescope, with which a beam with a small angular divergence forms a scanning area of the space, describing the scanning process conical surface. The target 11, fixed on the object, is made in the form of a cross, the four beams of which are formed by four groups of N photodetector cells respectively 16. Information on the position of the object is read continuously by registering the photodetector cells 16 exposed by the laser beam and the readings of the M-digit a digital angle converter 6 located on the shaft 3. This information is used to calculate the six coordinates necessary and sufficient for determining the position and orientation of the object in space. Elimination of the influence of pulsed light interference on

LyubOMIROV ANATOLY VIKTOROVICH

KARPOV MIHAIl VLADIMIROVICH

Kireeva gALINA ALEXANDROVNA + 7507635DISPLACEMENT TRANSDUCER WITH PHASE OUTPUT11 440052 PENZA11

Description

During the scanning process, describing the conical surface of the Target 11, fixed on the object, is made in the form of a cross, the four beams of which are formed by four groups of N photodetector cells, respectively, 16 and information on the position of the object is continuously measured by registering the numbers of during the laser beam scanning process of the photodetector cells 16 and the N-bit readings of the bottom digital angle converter 6 located on the shaft 30 This information & chi is used to calculate

six coordinates necessary and sufficient to determine the position and orientation of the object in space. The effect of pulsed light interference is eliminated by temporally selecting them for information pulses in four information processing units 7-10, a photo-receiving cell 16, made in the form of a hood with an optical band-pass filter installed inside it, selects the useful optical signal relative to the phono. howling of light interference in the angular deviations and the spectrum. 2 з.п0ф-л, 6 Il.

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The invention relates to the control and measurement technique and can be used to automatically control the dynamics of the position and orientation in a given area of space of various objects, for example, platforms with hardware, antenna devices, etc.

The aim of the invention is to increase the information content by determining six coordinates that determine the position and orientation of an object in space, improving accuracy by providing a small angular divergence of the scanning beam and discreteness of reading information about its position, increasing the reliability by eliminating the influence of pulsed light. - foreign interference from external sources, increased resolution by reducing the effect of background light interference.

Fig „1 shows the block diagram of the device; on. - block diagram of the information processing unit; on fig. 3 — device of the photodetector cell; figure 4 - timing diagrams illustrating the operation of the information processing units; on — a cross-shaped target and a trajectory of a bright Boro spot — the projection of a laser beam — onto the plane of the target in the absence of its inclination relative to the optical axis of the laser; Figure 6 illustrates the case of the relative position of the Scan cone and the coordinate system associated with the object.

The device contains (Fig. 1) a laser I, a scanning mechanism 2 with a hollow

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five

0

five

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shaft 3 mounted along the laser beam so that the axis of the hollow shaft 3 of the scanning mechanism (shaft 3) coincides with the optical axis of laser 1, focusing lens 4 mounted between shaft 3 and laser 1 coaxially with its optical axis, collimating lens 5 mounted inside shaft 3 so that its main optical axis is parallel to the optical axis of the laser 1, but is offset relative to it, an M-digit digital angle converter 6 (CPU) located on the shaft 3, four information processing units 7-10, the first group of the M inputs of each of which is connected Respectively with M outputs of CPU 6, and target 11, fixed on a controlled object, made in the form of a straight cross, four beams 12-15 (semi-axes 12-15) of which are formed by four groups of N linear and uniformly spaced, respectively 16 (OP cells 16), the outputs of which are connected respectively to the second groups of N inputs of the corresponding information processing units 7-10, four groups of outputs of which are outputs of the device and are intended for connection to a multi-bit computer interface bus

Each of the four blocks 7-10 of information processing consists (N 2) of N selective preamps 11 {, .. | 17), .. 017 || (Fig. 2 conditionally shows only one selective preamplifier N;), whose inputs form the second group of N inputs

corresponding to the information processing 7-10, the number code generator 18 (code generator 18) and the intersection pulse generator 19 (pulse generator 19), N inputs each of which are connected respectively to the outputs of the N selective preamplifiers 1 7,. .. 7, „„ „17N, register 20 when the angle (register 20), whose M inputs represent the first group of M inputs of the corresponding information processing block 7-10, and the multi-bit output combined with the multi-discharge output of the code 18 generator to the group of outputs of the corresponding information processing unit 7 - 10, and the time period generator 21 (interval generator 21), the output of which is connected to the blocking inputs of the code generator 18, the pulse former and register 20, and the input combined with the synchronization input of the register 20 and coi Inonii yield pulse shaper 19.

Each of the 4N photodetector cells 16 consists (fig. 3) of a hood 22 with a opening angle corresponding to the maximum monitored value of the angle of the object relative to the optical axis of the laser 1, which is installed along the scanning beam with the coaxial axis (lens 22) optical bandpass filter 23, optical lens. 24 and the photodetector diode 25, the receiving surface placed in the focus of the lens 24.

The device works as follows.

In the initial position, the optical axis of the laser 1 is directed to the center of the target 11 along the normal to its plane. The collimating lens 5 is located at such a distance from the focusing lens 4 so that the diameter of the light spot — the projection of the laser beam — does not exceed the size of the AF cell. The scanning mechanism 2 rotates the shaft 3, providing scanning of the target 11, at which the laser beam 1 describes the correct conical surface with a predetermined angle of opening 2 of the cone. The angle J1 is determined by the relation: jf arct., where D1 is the distance between the main optical axis of the collimating lens 5 and the optical axis of the laser 1; fk is the focal distance of the collimating

5362046

lenses 5. When choosing an angle y, the following condition is also observed: in the initial position (in the absence of deviations and displacement of the object with target 11), the intersection of the laser 1 of the 12-by-15 axis 11 to the target 11 takes place approximately in the middle of each of the 12 -15 axes. the controlled displacements and deviations of the object with a target are limited by the condition: at each revolution of the shaft 3, the scanning beam of the laser 1 crosses each of the four semi-axes 12-15

15 target 11. Thus, the specified range depends on the size of the target 11 o Simultaneously with scanning the target with a laser beam, the scanning mechanism 2 rotates the CPU 6 in such a way that the current value of the angle code unambiguously corresponds to the current value of the angle c /, sweep. For rational information processing, the value of оС 0 ° is combined with one of

25 axes (for example, 12), which is taken as the positive direction of the X axis. Combining the scanning mechanism 2, the collimating lens 5, the CPU 6 on one shaft 3 provides

30 adjustments the smallest errors in the optical path geometry and exact correspondence of the recorded angle to the csi sweep angle

When crossing the beam of the laser 1 OP

the cells 16 of the semiaxis 12 targets 11 in it. Jb

an electrical impulse is generated,

arriving at information processing unit 7 Similarly, when the laser beam 1 intersects semiaxes 13, 14, 15, 40, the pulses arrive at the information processing units 8, 9, 10, respectively. The signals from the information processing units 7-10 are fed to the output of the device and then to the multi-bit bus 45 of the computer interface for further processing.

Each of blocks 7-10 of information processing operates as follows.

cc Light flux consisting of a light pulse (Fig. 4a) of a laser beam that hits the FP cell 16 during the backlight scanning process and a pulse noise (Fig. 46), the press is formed by a photodiode diode 25 into an electrical signal (Fig. 4c) and is fed to the input of the corresponding selective preamp 1 / J In the selective preamps 17,. , 17 (, ...

. , , 1 7 jj, selection and formation of pulses with a logic level corresponding to the light pulses at the inputs of the FP cells 16 are carried out (Fig. 4d). The signals from the outputs of the N selective preamps 17, „.., 7; ... +., 17 enter the pulse shaper 19, where a single pulse is formed, regardless of which n and the input received a pulse. The signals from the selective preamplifiers 17 ,, 7., 17.;, ..,. 7у1 also go to the inputs of the shaper 18 of the code of the illuminated FP of the cell 16, where the number is determined and the code of the number of the illuminated of the FP of the cell 160 is generated. The laser radiation pulses are pulsed by blocking pulses (fig.4d), formed by the falling edges of informative pulses from laser 4 (). The duration of the guard time is determined from the ratio

about

 yy

(ABOUT

where T - the duration of the power | interval;

Tsk is the scan period; tH is the duration of the pulse from the laser beam at the output of the LEP cell 1 6;

t C - the maximum instability of the sweep period during one revolution of the shaft 3;

ta the maximum value of the time interval that amends during the meeting of the laser beam with the given semi-axis of the target 11 due to the movement of an object that 4, moving towards or away from the scanning beam, will change the period Tc of the meeting of the semi-axis 11 of the beam with the beam the side of the reduction or increase, respectively, is the “blocking impulse from the output of the former 21 interval arrives on. the inputs of blocking the imaging unit 18, the imaging unit 19 of the pulse and the register 20. In register 20, the scan angle code from the CPU 6 is recorded at the moment of intersection of the laser beam with the semi-axis 12 (13, 14, 15) of the target I. This moment is determined by the synchronization code register 20 of the pulse, which comes from the output of the former 19 pulse "

The output code from the imaging unit 18 of the code of the illuminated OP cell 16 and the angle code of the register 20, corresponding to the given intersection moment, are transmitted to the output of the device and then to the multi-bit bus of the computer interface for further processing and calculating the coordinates of the object

Laser beam 1 is a parallel beam of light, characterized by a narrow (wavelength) band. During the scanning process, the corresponding FP cell, 16, the laser beam, together with the background light interference, hits the optical bandpass filter 23, which selects the laser beam from the spectrum relative to the background light interference. Then the laser beam is focused by the optical lens 24 onto the receiving surface of the photodetector diode 25, generating its output information electric impulse

In the absence of inclination of the target 11 (Fig. 5) relative to the optical axis of the laser 1 (Fig. 1), the trajectory 26 of Fig. 1 of the light spot 27 (the projection of the laser beam on the plane of the target 11) is a circle. However, in the general case, the path of the light spot 27 is an ellipse, the eccentricity and orientation of which is relative to the axes Ґ and J7 of the cross-shaped target AND depends on the orientation characteristics of the object, for example, specified by Euler angles (Fig. 6):

5 is the polar angle (between the Z axis of the fixed XYZ system and the Ј axis of the system associated with the object, Ј Ј, which shows the tilt of the object relative to the optical axis of the laser 1 (Fig. 1);

Z is the azimuthal angle of the line of nodes 1 in the XYZ system, which shows which way the object is tilted;

 The azimuthal angle of the line of nodes 1 in the system associated with the object, which shows the rotation of the object that has so far only inclined N, AROUND AXIS V.

The small semi-axis of the ellipse of the light spot trajectory along the plane (, {) during the scanning process and its location on this plane is a function of the spatial position of the object: distance Z0 from the top of the scanning cone along its axis and lateral displacement (XQ, Y, 0) from the axis During the scanning process, the laser beam intersects four semi-axes 12-15 (FIG.) of the target 1 1 at the points with coordinates, {, t, t, which are registered by the device in the form of numbers illuminated by the laser beam of the 16: Nt, F cell,

N:, N.

 Coordinates and numbers are connected in this case through the quantization step q of four semiaxes 12.- 15 by the relation:

; -NSqj

Ј q;

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R

h

-N q;

-N; q;

(2)

| G (cosCf cosV-sinCpsinVcos) + Xe- (sin (f sJn-0 + Z0) tg in cosoi% (sincpcosV-cos Cf sin () + Yo- (sin-) + Z0) tgj sin oiv "- (- coscf sin -sincpcos cos-) + X0 (Sozf sin + Z0) tgy coseCj 2 (-Bintf sincp + costfcos cos) + Ye (j7f cos (sin + Z0) tgJ sinoLh - (coscfcos -sintf sin cos 3) + X0 ( in f sin + Z0 tgj cos od (s in q cos Cfsin cos 9) + Y0 (sinC; sin 9 + Z0) tgj sinoC - jT (-cosq sin ({-sinq cos cos}) + Xe- (cozy sin 9) tg cosoi2- (-sin sin + cos coscpcos)) + Y6 (cos (sin + Z0) tg sinoir

40

the fourth pair of equations in (3) with the appearance of the fourth beam intersection with the # axis at the Ј point value of six characteristics is adjusted, based on the last three pairs of equations (3). Thus, information on the position of the object is read continuously by registering the numbers of the illuminated PI cells 16 and taking readings from the M-digit CPU 6 in three

For an exhaustive description of the position of an object in space, it is necessary and sufficient to know six coordinates (X0, Y0, Z0, -E, (f, (j) j), but in the system (3, the position of the object is described by eight equations, thus, any two equations from system (3) follow from the remaining six. For example, (, 1, Ј4, vol,%, u6U), then ({, o.p) are obtained automatically, which geometrically corresponds to, - the consecutive moments of intersection to find the fourth the point of intersection of the laser beam with the target 11, and, from the point of view of statics, a superfluous pair of equations in the system (3) Used in calculations to correct Dynamics Динами For example, after dialing the first three pairs of equations of system (3) after intersecting the Ј and Ј axes with a laser beam at three points, Ј, Ј, having the same angles L, dL o & scan, at which these intersections occurred, the values of the six characteristics of the object are determined (X0, YO Z0, 0, f, (j), With the occurrence

50

scanning laser beam with semiaxes 12-15 cross-shaped target 11

Claims (3)

Invention Formula 1 o A device for determining the position and orientation of an object, containing a laser, a focusing lens mounted along the laser beam and a laser beam scanning mechanism along a cone, whose hollow shaft is coaxial with the laser beam, M-fold digital angle converter located on the hollow fur shaft Simultaneously with the appearance of impulses. Sa on one of the half axes 12-15, for example, +, in the corresponding block 7-10 of information processing (Fig. 1), the scanning angle is recorded, for example, Otto With the completion of one full revolution of the laser beam, four pairs of recorded data (, & k + og iP, / Ј), carrying useful information comes from the outputs of the blocks, 7 - 10 information processing in an external, relative to this, device (computer) for calculating the spatial and angular coordinates X, Y, Ј,), Cf, Cf1 target 11 (object) from the ratio: (3) the fourth pair of equations in (3) with the appearance of the fourth beam intersection with the # axis at the Ј point value of six characteristics is adjusted, based on the last three pairs of equations (3). Thus, information on the position of the object is read continuously by registering the numbers of the illuminated PI cells 16 and taking readings from the M-digit CPU 6 in three consecutive crossing times consecutive crossing times scanning laser beam with semiaxes 12-15 cross-shaped target 11 Invention Formula 1 o A device for determining the position and orientation of an object, containing a laser, a focusing lens mounted along the laser beam and a laser beam scanning mechanism along a cone, whose hollow shaft is coaxial with the laser beam, an M-digit digital angle converter located on the hollow shaft the scanning engine j and the target, made in the form of a cross, mounted on a controlled object, characterized in that, in order to increase the information content by determining the six coordinates that determine the position and orientation e) in space, and increase in accuracy due to the low angular divergence of the scanning and discreteness of reading information about its position; it is equipped with a collimating lens fixed inside the hollow shaft of the scanning mechanism so that its main component the axis is parallel to the optical laser and is offset relative to the rtee, and forming with the focusing line; Oh telescope, four processing units, the first group of the inputs of each of which are connected respectively to the M outputs of the digital angle transducer, and four groups of N photodetector cells located with uniform naked on four semi-axial targets, the outputs of each group of photoreceiver cells are connected respectively to the second group of N the inputs of the corresponding information processing unit; 6, the four groups of outputs of the four information processing units are the outputs of the device. 2. The device, which is based on the fact that, in order to increase the reliability by eliminating five 0 five 0 five Neither the effect of pulsed light interference from extraneous sources, each of the four information processing units is made in the form of N selective preamplifiers, the inputs of which form the second group of N inputs of the information processing unit, a number code generator and an intersection pulse generator, N inputs of each of which are connected respectively with the outputs of N selective preamps, the register of the angle code, the M inputs of which represent the first group of M inputs of the information processing unit, and the multi-output output En with the multi-bit output of the number code generator in the output group of the information processing unit, and the time interval generator, the output of which is connected to the blocking inputs of the number code and intersection pulse generator and the angle code register, and the input is combined with the angle code synchronization input and connected to the output intersection pulse former. 3. The device according to claim 2, wherein, in order to increase the resolution by reducing the effect of background light interference, each of the 4N photodetector cells is designed as a hood in which an optical band-pass optical filter lens and photodetector diode, the receiving surface placed in the focus of the lens. Phi #g Fi.CH FIG. five fc