阅读说明：本技术 基于衍射分光逆向干涉的普适型回转惯性运动测量系统 (Universal rotary inertial motion measurement system based on diffraction beam splitting reverse interference ) 是由 王轶君 邓剑平 王宇琛 邹畅 宗雯 楼晓雪 高向鹏 王舒婷 卢昱坤 张凤雯 赵斌 于 2021-09-08 设计创作，主要内容包括：本发明涉及一种基于衍射分光逆向干涉的普适型回转惯性运动测量系统。为提供一种普适型回转惯性运动测量装备。是可旋转圆形平台上面在纵向基准直径线的圆心前后半径线上分别设置反射三棱镜和向反射三棱镜两对称侧面分别投射激光束的衍射激光器,圆形平台上面在反射三棱镜前方左右两侧、在圆心左右两侧、在衍射激光器左右两侧以及在衍射激光器后方,分别设置左右前反射镜、左右中反射镜、左右后反射镜以及正后反射镜；圆形平台上面在反射三棱镜上方设置斜立的透射反射镜,透射反射镜的反射面侧方向自内至外依次间隔设置扩束镜及毛玻璃观察屏。配计算机的摄像机拍摄毛玻璃观察屏显示的光束图像。具有能测算微小回转变化,且普适性好的优点。(The invention relates to a universal rotary inertial motion measurement system based on diffraction beam splitting reverse interference. Provides a universal rotary inertia motion measuring device. A reflection prism and a diffraction laser which respectively projects laser beams to the symmetrical side surfaces of the reflection prism are respectively arranged on the front and rear radius lines of the circle center of a longitudinal reference diameter line on a rotatable circular platform, and a left front reflector, a right front reflector, a left middle reflector, a right rear reflector, a left rear reflector and a right rear reflector are respectively arranged on the circular platform at the left and right sides in front of the reflection prism, at the left and right sides of the circle center, at the left and right sides of the diffraction laser and at the rear of the diffraction laser; an oblique transmission reflector is arranged above the reflection prism on the round platform, and beam expanders and ground glass observation screens are sequentially arranged at intervals from inside to outside in the direction of the reflection surface side of the transmission reflector. A camera equipped with a computer captures the beam image displayed on the frosted glass viewing screen. The method has the advantages of capability of measuring and calculating the tiny rotation change and good universality.)

1. A universal rotary inertia motion measuring system based on diffraction beam splitting reverse interference is characterized in that a reflective prism and a diffraction laser for projecting laser beams to two symmetrical sides of the reflective prism are respectively arranged on the front radius line and the rear radius line of the circle center of a longitudinal reference diameter line on a rotatable circular platform, and a left front reflector, a right front reflector, a left middle reflector, a right rear reflector and a right rear reflector are respectively arranged on the circular platform on the left side and the right side in front of the reflective prism, on the left side and the right side of the circle center, on the left side and the right side of the diffraction laser and behind the diffraction laser; the left side laser beam projected to the left side surface of the reflection prism by the diffraction laser sequentially passes through the left front reflector, the left middle reflector, the left back reflector, the right back reflector and the right middle reflector to project the anticlockwise laser beam to the right front reflector, and the right side laser beam projected to the right side surface of the reflection prism by the diffraction laser sequentially passes through the right front reflector, the right middle reflector, the right back reflector, the left back reflector and the left middle reflector to project the clockwise laser beam to the left front reflector to form a bottom light splitting path; set up oblique standing's transmission reflector above the reflection prism above the circular platform, the reflection face side direction of transmission reflector sets up beam expander and ground glass observation screen from interior to exterior interval in proper order, and the anticlockwise laser beam through right front reflector reflection passes through transmission reflector transmission in proper order, and the beam expander expands and then throws on ground glass observation screen, and clockwise laser beam through left front reflector reflection passes through transmission reflector reflection in proper order, and beam expander expands and then throws on ground glass observation screen and constitute the top layer and interfere the light path.

2. The system according to claim 1, wherein the left laser beam projected to the left side of the reflective triple prism by the diffraction laser sequentially passes through the counterclockwise spiral lifting annular optical path of the left front, left middle, left back, right back and right middle reflectors to project the counterclockwise laser beam to the right front reflector, and the right laser beam projected to the right side of the reflective triple prism by the diffraction laser sequentially passes through the clockwise spiral lifting annular optical path of the right front, right middle, right back, left back and left middle reflectors to project the clockwise laser beam to the left front reflector.

3. The universal rotary inertial motion measurement system based on diffraction beam splitting reverse interference as claimed in claim 2, wherein the counterclockwise spiral lifting annular optical path is formed by that the counterclockwise laser beam projected to the left side surface of the reflective triple prism by the diffraction laser is lifted and reflected to the left middle reflector by the left front reflector, and the counterclockwise laser beam is projected to the right front reflector by the right middle reflector through the midway reflector and then lifted and reflected by the right front reflector; clockwise spiral uplift annular light path is that the clockwise laser beam that the diffraction laser instrument projected reflection prism right flank passes through right preceding speculum uplift in proper order and reflects in right side in the speculum, the speculum projects clockwise laser beam to left preceding speculum in the left side through midway speculum, reflects out by left preceding speculum uplift again.

4. The system according to any one of claims 1-3, wherein the left front mirror and the right front mirror are both arranged in an outward-looking manner to raise the optical path.

5. The system for measuring universal rotary inertial motion based on diffraction-spectroscopy reverse interference according to any one of claims 1-3, wherein the left middle reflector, the left rear reflector, the right rear reflector and the right middle reflector are vertical reflectors for forming a midway circulating light path; before the reflector is arranged, the incident light is adjusted by the light shielding plate arranged at the position of the reflector to be capable of striking on the central axis of the light shielding plate, and the reflector is replaced and installed after the incident light is adjusted.

6. The system according to claim 1, wherein the front left and right reflectors are disposed on the circular platform in front of the reflective prism and symmetrically on the left and right sides, the middle left and right reflectors are disposed on the circular platform in the middle symmetrically on the left and right sides, the rear left and right reflectors are disposed on the circular platform in symmetrically on the left and right sides, and the rear right reflector is disposed on the circular platform directly behind the diffractive laser.

7. The system according to claim 1, wherein the diffractive laser is a vertical diaphragm disposed in front of the longitudinal horizontal laser, or a vertical diaphragm disposed on the optical path between the longitudinal horizontal laser and the reflective triple prism.

8. The system of claim 1, wherein the counter-clockwise laser beam reflected by the left front reflector and the clockwise laser beam reflected by the right front reflector are reflected and transmitted by the reflective-transmissive mirror, interfere with each other, pass through the beam expander, and irradiate on the ground glass viewing screen.

9. The system for measuring universal rotary inertial motion based on diffraction-spectroscopy reverse interference of claim 1, wherein a beam image camera or a video camera of the measuring system is arranged on the circular platform, and the beam image camera or the video camera is used for shooting two interfered beam images displayed on the ground glass observation screen.

10. The system according to claim 9, wherein the circular platform of the intelligent tachometer is provided with a hinged support, and the beam image camera or video camera and the intelligent tachometer are in communication connection via a wired or wireless communication mode with a computer for measuring and calculating two interference beam images; or the intelligent tachometer is provided with a rotating speed display camera or a video camera for shooting and displaying the rotating speed in real time, and the light beam image camera or the video camera and the rotating speed display camera or the video camera are in communication connection through a wireless or wired communication mode and are used for measuring and calculating two interference light beam images.

Technical Field

The invention relates to a rotary motion measuring device, in particular to a universal rotary inertial motion measuring system based on diffraction beam splitting reverse interference.

Background

The law of mechanics states that: an observer locked in a black box with constant linear translation cannot know the motion condition of the observer, but can accurately measure the acceleration and the rotation by using a mechanical accelerometer and a gyroscope. This is the basis for inertial guidance and navigation. For example: high-precision interference type fiber optic gyroscopes are generally adopted in aerospace and space applications. The optical system can provide three-dimensional angular velocity, position, attack angle and sideslip angle for an airplane, realize the tracking and determination of rocket launching and launching, and can also be used for space vehicle stabilization, photography/surveying and mapping, attitude measurement control, motion compensation, EO/FLIR stabilization, navigation, flight control and the like, wherein the high-precision and high-reliability optical fiber gyroscope and GPS combined attitude determination becomes a typical configuration of an attitude determination system of spacecrafts at home and abroad.

In 1913, Sagnac demonstrated experimentally that an optical system without moving parts could also detect rotation relative to inertial space. He used a ring interferometer and showed that rotation caused the light to phase-difference between the two counter-propagating paths. However, due to its very limited sensitivity, it is far from the practical application condition of a revolution speed sensor.

The rotary inertial motion system is based on Sagnac Effect (Sagnac Effect): a beam of light emitted by the same light source is split into two beams, the two beams converge after circulating in the same loop along opposite directions for a circle, then interference is generated on a screen, and when the angular velocity of rotation exists in the plane of the loop, interference fringes on the screen move. However, the prior art does not have a universal rotary inertial motion measurement system.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provides a universal rotary inertial motion measurement system based on diffraction beam splitting reverse interference. The design scheme of the rotary inertial motion system structure and the matched measurement system aims at converting the micro angular velocity into the change of the optical interference pattern, proves that the working principle of the fiber-optic gyroscope can be realized under the condition of a free light path, and the expression form is visual. Meanwhile, the precision of the device is improved, so that the device can be flexibly applied to various working fields; the micro rotation change is expressed in a more visual and concrete form by the parametric transformation of the angular velocity-optical path difference-interference pattern.

In order to achieve the purpose, the universal rotary inertia motion measurement system based on diffraction beam splitting reverse interference is characterized in that a reflective prism and a diffraction laser for projecting laser beams to two symmetrical sides of the reflective prism are respectively arranged on a front radius line and a rear radius line of a circle center of a longitudinal reference diameter line on a rotatable circular platform, and a left front reflector, a right front reflector, a left middle reflector, a right middle reflector, a left rear reflector and a right rear reflector are respectively arranged on the circular platform at the left side and the right side in front of the reflective prism, at the left side and the right side of the circle center, at the left side and the right side of the diffraction laser and at the rear of the diffraction laser; the left side laser beam projected to the left side surface of the reflection prism by the diffraction laser sequentially passes through the left front reflector, the left middle reflector, the left back reflector, the right back reflector and the right middle reflector to project the anticlockwise laser beam to the right front reflector, and the right side laser beam projected to the right side surface of the reflection prism by the diffraction laser sequentially passes through the right front reflector, the right middle reflector, the right back reflector, the left back reflector and the left middle reflector to project the clockwise laser beam to the left front reflector to form a bottom light splitting path; set up oblique standing's transmission reflector above the reflection prism above the circular platform, the reflection face side direction of transmission reflector sets gradually beam expander and ground glass observation screen from inside to outside, and the anticlockwise laser beam through right front reflector reflection passes through transmission reflector transmission in proper order, and the beam expander expands the beam and then throws on ground glass observation screen, and the clockwise laser beam through left front reflector reflection passes through transmission reflector reflection in proper order, and beam expander expands the beam and then throws on ground glass observation screen and constitute the top layer and interfere the light path. During the use, adopt intelligent tachometer to measure rotatable circular platform's rotatory linear velocity, fixed camera equipment carries out real-time detection and record as image capture equipment to the image on the ground glass observation screen on the circular platform. Rotation of the rotatable circular platform causes translation of the interference fringes and image changes on its image-receiving plate. The change scale of the movement of the interference fringes caused by the rotation of the experimental platform is calculated by analyzing the image recorded by the image capturing device in real time, and the phase difference generated by the rotation of the circular platform between two opposite-direction transmission light rays is reversely deduced by calculating according to a theoretical principle. And calculating the change angular displacement and the angular acceleration of the whole system according to the phase difference, and adjusting the system by the data feedback to meet specific purposes, such as: the whole system is dynamically maintained at a fixed acceleration value all the time.

The structural design of the whole system is a novel spiral ascending free light path. The design of the free light path and the matched measuring device are mutually linked, and the purposes of reading and adjusting the relative displacement change data generated in the rotation process by the rotary inertial motion system are jointly realized.

The free optical path of the rotary inertial motion system is composed of a bottom light splitting optical path and a top interference optical path, and a rotary inertial motion system structure similar to the principle of the fiber-optic gyroscope is formed under the combined action of the two parts. The supporting measuring mode of design in this system has adopted intelligent digital tachometer to measure and calculate rotatable circular platform's rotational speed to shoot and the image recording through the interference fringe behind the free light path of camera fixing on rotatory experiment circular platform, be convenient for carry out image analysis to the relative change data that take place in the system. The gyroscope has the advantages that the gyroscope can be used for figuratively and specifically measuring and calculating tiny rotation changes, is suitable for teaching and popular science demonstration, is small in size and high in precision, is more suitable for being combined into a gyroscope for measuring and controlling flight postures, and integrates experiment verification and demonstration.

As optimization, the left laser beam projected to the left side surface of the reflection prism by the diffraction laser sequentially passes through the left front, the left middle, the left back, the right back and the anticlockwise spiral lifting annular light path of the right middle reflector to project the anticlockwise laser beam to the right front reflector, and the right laser beam projected to the right side surface of the reflection prism by the diffraction laser sequentially passes through the right front, the right middle, the right back, the left back and the clockwise spiral lifting annular light path of the left middle reflector to project the clockwise laser beam to the left front reflector.

For optimization, the anticlockwise spiral lifting annular light path is formed by that an anticlockwise laser beam projected to the left side surface of the reflection prism by the diffraction laser is lifted and reflected to the left middle reflector through the left front reflector, and the anticlockwise laser beam is projected to the right front reflector through the right middle reflector by the middle reflector and then lifted and reflected by the right front reflector; clockwise spiral uplift annular light path is that the clockwise laser beam that the diffraction laser instrument projected reflection prism right flank passes through right preceding speculum uplift in proper order and reflects in right side in the speculum, the speculum projects clockwise laser beam to left preceding speculum in the left side through midway speculum, reflects out by left preceding speculum uplift again.

Preferably, the left front reflector and the right front reflector are arranged in an outward-upward mode capable of lifting the light path. In order to separate the laser beam into light rays which can be independently transmitted to two directions, the laser beam splitter uses the reflecting triple prism and achieves the purpose of splitting the light beams by utilizing the function of refracting the light rays by the triple prism. Since a single color laser is used in the experiment, the possibility that the prism will be dispersed is eliminated, and only two-directional refraction is possible. In order to ensure that the refracted light rays can have a large enough refraction angle, a reflective triangular prism with the apex angle of 90 degrees is further adopted. In the invention, the circular reflector is used to change the direction of light rays so as to achieve the aim of spiral rising of the light rays in a free light path. The direction of the reflected light in the free light path can be adjusted by using a support device with an adjustable reflector orientation.

As optimization, the left middle reflector, the left rear reflector, the right rear reflector and the right middle reflector are all vertical reflectors for forming a midway circulating light path; before the reflector is arranged, the incident light is adjusted by the light shielding plate arranged at the position of the reflector to be capable of striking on the central axis of the light shielding plate, and the reflector is replaced and installed after the incident light is adjusted. The socket base plate of the reflector is screwed on the circular platform, a vertical base pipe is upwards manufactured on the socket base plate, and the vertical base pipe is inserted into the base of the vertical supporting rod of the reflector and is fixed by a transverse fastening screw. The upper end of the vertical supporting rod is fixedly provided with a left middle reflector, a right middle reflector, a left rear reflector, a right rear reflector and a circular mirror frame of the front rear reflector. The U-shaped hinged frame of the left front reflector and the right front reflector is fixedly arranged at the upper end of the vertical supporting rod, and the U-shaped hinged frame is hinged with the circular ring-shaped mirror frame of the right front reflector through a cross shaft attached with a fastening screw. Therefore, the directions of all the reflectors are adjusted through the relative rotation of the vertical supporting rod and the vertical base tube, and the elevation angles of the front reflectors at the left and right ends are adjusted through the relative rotation of the U-shaped hinged frame and the circular ring-shaped mirror frame. A vertical support is fixedly arranged on the circular platform, a U-shaped support of a longitudinal horizontal laser is fixedly arranged on the vertical support through an adjustable screw, and the horizontal laser penetrating through the end ring is adjusted and fixed through a plurality of parallel adjustable fastening screws by the end rings arranged at the front end and the rear end of the U-shaped support respectively.

Preferably, the left front reflector and the right front reflector are arranged on the two sides of the circular platform in front of the reflection prism in bilateral symmetry, the left middle reflector and the right middle reflector are arranged on the two sides of the circular platform in middle bilateral symmetry, the left rear reflector and the right rear reflector are arranged on the two sides of the circular platform in bilateral symmetry, and the right rear reflector is arranged right behind the circular platform in diffraction laser.

Preferably, the diffraction laser is characterized in that a vertical diaphragm is arranged in front of the longitudinal horizontal laser, or the vertical diaphragm is arranged on a light path between the longitudinal horizontal laser and the reflective prism. A three-disc vertical seat is fixedly arranged on the circular platform at a vertical interval, a front extending end part of an F-shaped support with two side arms upward is fixedly arranged on a middle disc of the three-disc vertical seat, a vertical diaphragm is arranged between the two side arms of the F-shaped support, and the vertical diaphragm is fixedly extruded between the front end of a longitudinal screw and a front side arm by a longitudinal screw which penetrates through a rear side arm. A reflective prism is fixedly arranged on the top-layer disk of the three-disk vertical seat, and a shading block is preferably arranged on the top-layer disk behind the reflective prism. The socket base plate is fixedly screwed on the transmission reflector in front of the three-disc vertical seat on the circular platform, a vertical base pipe is manufactured upwards on the socket base plate, and the vertical base pipe is inserted into the inverted L-shaped vertical rod base part of the transmission reflector and is fixed by a transverse fastening screw. The transmission reflector is arranged at the cross arm end extending out of the upper end of the L-shaped vertical rod towards the center direction of the platform, the cross arm is preferably a transverse telescopic arm with adjustable length, and the extending direction of the cross arm and the height of the L-shaped vertical rod can be adjusted by loosening the transverse fastening screw. The front end of the cross arm is fastened with the rear part of the transmission reflector through an adjustable screw, and the pitching angle of the transmission reflector can be adjusted by loosening the adjustable screw. An inverted T-shaped seat is fixedly installed on the circular platform, a ground glass observation screen is arranged at the upper end of a vertical rod of the inverted T-shaped seat, a transverse extending arm end of an L support is fixedly installed on a base plate of the inverted T-shaped seat, and the beam expanding lens is arranged at an upper extending arm end of the L support. The vertical diaphragm is a vertical diaphragm with a 300-line grating, and the transmission reflector is a 5:5 transmission reflector. The laser in the bottom layer light path is diffracted by the vertical diaphragm of the 300-line grating, is divided into two diffracted beams, and is respectively transmitted along opposite directions. Then the two beams of light are reflected by a plurality of groups of reflectors respectively and then emitted to a 5:5 transmission reflector to generate interference superposition. The attitude measurement and control comprises the following steps: the matched measuring facility detects and captures an image of interference fringes generated in the moving process of the whole rotary inertial motion system, and analyzes corresponding data such as optical path difference and the like through a change image of the interference fringes in a certain time period; and further analyzing and processing the data according to the Sagnac effect, feeding the data back to the rotary inertial motion system, and adjusting the motion process of the rotary inertial motion system, so that the whole system achieves the aim of dynamic balance. The vertical horizontal laser is a laser pen which is vertically and horizontally arranged, and a vertical diaphragm which is arranged in front of or in front of the laser pen is used for restraining incident light, so that the interference of stray light is reduced, and the influence of irrelevant factors on an experiment is reduced. The vertical diaphragm performs a preliminary diffraction process on the incident light with a grating constant d = 300.0/mm. In order to keep the laser pen in a stable working state all the time in the experimental process, the support capable of adjusting the emergent light direction of the laser pen along with the actual situation is designed and manufactured according to the size of the laser pen and the height of light in a free light path, and a button locking device is further added on the laser pen in consideration of the instantaneity of a switch button of the laser pen, so that the laser pen can be always opened in the experimental process, and the emergent light of the laser pen can be stably emitted to a slit in the front. The laser used in the present invention, i.e. the laser transmitter, is a 303, 500nm green laser pointer with a key to lock the laser to avoid power loss.

And optimally, the anticlockwise laser beam reflected by the left front reflector and the clockwise laser beam reflected by the right front reflector are respectively reflected and transmitted by the reflection-transmission lens, interfere with each other, pass through the beam expanding lens and irradiate on the ground glass observation screen. The interference fringe image finally formed by the free light path is presented in the form of a small light spot, and is inconvenient for observation and recording sampling, so that a beam expanding lens is arranged behind the reflection and transmission lens and in front of an observation screen of the interference fringe, and plays a role in expanding beams, and the image of the interference fringe is amplified to be convenient for observation and recording. Any mirror may be used to split the beam. The experiment used the laser technology, so the dielectric film mirror was used as a reflective transmissive mirror type beam splitter. The angle of incidence determines the angle of exit of the output beam, perhaps 45 ° being the most common, but of course other values are possible, and the angle of exit will affect the properties of the beam splitter. A wide range of power splitting ratios can be achieved by using different dielectric films. According to the practical situation in the experimental process, the method adopts the following steps that: 5 reflective transmissive mirror beam splitter.

And as optimization, a light beam image camera or a video camera of the measuring system is arranged on the circular platform, and the light beam image camera or the video camera is used for shooting two interfered light beam images displayed by the ground glass observation screen. The three parallel circular platforms respectively provided with the optical device are arranged together in a mutually vertical mode to form a measuring part and a combined measuring and calculating part of the gyroscope, and the measuring and calculating part is used for measuring and controlling the attitude of the aircraft.

As optimization, a hinged support is arranged on a circular platform matched with the intelligent tachometer, and the light beam image camera or the video camera is in communication connection with the intelligent tachometer through a wired or wireless communication mode to be used for measuring and calculating two interference light beam images; or the intelligent tachometer is provided with a rotating speed display camera or a video camera for shooting and displaying the rotating speed in real time, the light beam image camera or the video camera and the rotating speed display camera or the video camera are in communication connection through a wireless or wired communication mode and are used for measuring and calculating two interference light beam images, and the design is used for teaching experiments. The computer is used for popular science demonstration after being matched with a wall-mounted display screen. When the device is used for popular science demonstration, a transparent dome glass cover for protecting all optical devices is arranged on the circular platform. The circular platform can be further provided with a speed-regulating rotary driving mechanism. The articulated support provided by the circular platform is preferably a slewing support. In the experimental process, a contact type rotating speed measuring mode is used, and the rotating speed of the experimental circular platform is calculated through the radius ratio between the synchronous wheel and the circular platform, wherein the synchronous wheel is in contact with the edge of the circular platform, and the intelligent tachometer is in contact with the edge of the circular platform.

The specific experimental process is as follows: and adjusting the laser to be horizontal, enabling the laser emitted by the laser to vertically pass through the slit of the vertical diaphragm and be diffracted, and irradiating the diffracted central main laser on two isosceles side surfaces of the right-angle triple prism. Then adjusting each reflector arranged at the periphery of the experimental platform to enable the forward light and the backward light to completely wind a circle and finally irradiate on the projection reflector arranged above the right-angle triple prism. The transmission reflector changes the propagation direction of clockwise light, so that two beams of light propagated along the opposite direction in the top layer light path pass through the beam expander and then irradiate on the ground glass observation screen fixed in front of the transmission reflector. After the laser transmitter is started, a light beam image camera for shooting interference fringes on the installation experiment table and a rotating speed display camera for shooting rotating speed data on the intelligent digital tachometer are started. When the round rotatable experiment platform is rotated, the high-brightness laser parallel to the experiment platform can be observed to be emitted from the laser emitter, and the light beam irradiates on the grating vertically arranged on the laser and is diffracted by the grating. Positive and negative first-order diffraction fringes produced by the grating diffraction phenomenon can be further hit to two isosceles side surfaces of the right-angle triangular prism to be subjected to mirror reflection, the two reflected light rays after the mirror reflection are respectively transmitted along clockwise and anticlockwise directions, the light rays transmitted along clockwise sequentially pass through clockwise midway reflectors, and the light rays transmitted along anticlockwise are vice versa, namely transmitted along the sequence of the anticlockwise midway reflectors. And when the circular rotatable experiment platform stops rotating, the laser is firstly turned off, and then videos shot by the two cameras are stored. The rotation direction of the circular rotatable experiment platform is changed, the experiment is repeated, and a plurality of groups of photographic videos are shot. After the videos of all the experiment groups are shot and stored, the camera is taken down from the fixing frame, and the experiment videos are read and uploaded.

In summary, the bottom-layer light splitting optical path design: in the experimental process, a laser arranged horizontally emits laser, and then the laser passes through a vertical diaphragm arranged in front of a triangular mirror and is diffracted. The diffracted 1-order stripes respectively hit the two side surfaces of the reflective triangular prism and are reflected. The reflected light rays respectively irradiate the right front reflector and the right front reflector, and then are reflected in the clockwise direction and the anticlockwise direction in sequence by virtue of the midway light path reflectors placed at proper angles, so that the light rays have a spiral rising trend (clockwise or anticlockwise), and two annular reflected light paths in the clockwise direction and the anticlockwise direction are formed.

Designing a top-layer interference light path: the design of the top interference light path of the free light path in the rotary inertia motion system is realized, the light which is transmitted clockwise and anticlockwise in the bottom light path is further emitted to the transmission reflector placed on the top layer, the clockwise light and the anticlockwise light respectively pass through the reflection and the transmission effects on the transmission reflector, and then the two beams of light are interfered and pass through the beam expander to irradiate on the ground glass observation screen. Meanwhile, in the design scheme of the matched measurement system, a camera is used for shooting the observation screen, and then the sampling of the interference image is completed, so that the further analysis is facilitated.

The laser light source emits an initial light beam, and the initial light beam is diffracted through a vertical diaphragm arranged in front of the triangular mirror. After diffraction_±The grade 1 stripes will hit the two sides of the reflective prism and will be reflected. The two reflected light beams respectively strike the left and right front reflectors with elevation angles on the left and right sides. The elevation angles of the left front reflector and the right front reflector enable the light path to show a spiral rising trend, the light path finally irradiates to the transmission reflector at the top layer, the light rays of the clockwise light path are reflected, the light rays of the anticlockwise light path are transmitted, and the light rays are converged into tail end light rays after passing through the transmission reflector.

By adopting the technical scheme, the universal rotary inertial motion measurement system based on the diffraction beam splitting reverse interference has the advantages that the micro rotary change image can be measured and calculated specifically, the system is suitable for teaching and popular science demonstration, and the advantages of small size and high precision are more suitable for being combined into a gyroscope for measuring and controlling the flight attitude, and the experimental verification and demonstration are integrated.

Drawings

Fig. 1-2 are a schematic bottom-layer optical path structure and a schematic bottom-layer optical path structure of a first embodiment of a universal rotary inertial motion measurement system based on diffraction-beam-splitting reverse interference according to the present invention. Fig. 3-4 are schematic top view and perspective view of a second embodiment of the universal rotational inertial motion measurement system based on diffractive-beam-splitting reverse interference according to the present invention. Fig. 5-8 are diagrams illustrating the measurement principle of the general rotation inertial motion measurement system based on diffraction beam splitting reverse interference.

Detailed Description

In the first embodiment, as shown in fig. 1-2, the general rotational inertial motion measurement system based on the diffraction beam splitting reverse interference of the present invention is that a reflective prism 13 and a diffraction laser for projecting laser beams to two symmetric sides of the reflective prism 13 are respectively disposed on the front and rear radius lines of the center of a circle of a longitudinal reference diameter line on a rotatable circular platform 10, and a left front reflector 7 and a right front reflector 1, a left middle reflector 6 and a right middle reflector 2, a left rear reflector 5 and a right rear reflector 3, and a front rear reflector 4 are respectively disposed on the front and rear sides of the reflective prism 13, on the left and right sides of the center of a circle, on the left and right sides of the diffraction laser, and behind the diffraction laser on the circular platform 10; the left side laser beam projected to the left side surface of the reflection prism 13 by the diffraction laser passes through the left front reflector, the left middle reflector, the left back reflector, the right middle reflector in sequence to project the anticlockwise laser beam to the right front reflector 1, and the right side laser beam projected to the right side surface of the reflection prism 13 by the diffraction laser passes through the right front reflector, the right middle reflector, the right back reflector, the left back reflector and the left middle reflector in sequence to project the clockwise laser beam to the left front reflector 7 to form a bottom light splitting path; set up oblique standing's transmitting mirror 8 above reflection prism 13 on circular platform 10, the reflecting surface side direction of transmitting mirror 8 sets up expander mirror 9 and ground glass observation screen 90 from inside to outside interval in proper order, the anticlockwise laser beam that reflects through right front reflector 1 passes through transmitting mirror 8 transmission in proper order, on ground glass observation screen 90 is thrown after the expander mirror 9 expands the beam, and the clockwise laser beam that reflects through left front reflector 7 passes through transmitting mirror 8 reflection in proper order, and constitute top layer interference light path on ground glass observation screen 90 is thrown after the expander mirror 9 expands the beam. During the use, adopt intelligent tachometer to measure rotatable circular platform's rotatory linear velocity, fixed camera equipment carries out real-time detection and record as image capture equipment to the image on the ground glass observation screen on the circular platform. Rotation of the rotatable circular platform causes translation of the interference fringes and image changes on its image-receiving plate. The change scale of the movement of the interference fringes caused by the rotation of the experimental platform is calculated by analyzing the image recorded by the image capturing device in real time, and the phase difference generated by the rotation of the circular platform between two opposite-direction transmission light rays is reversely deduced by calculating according to a theoretical principle. And calculating the change angular displacement and the angular acceleration of the whole system according to the phase difference, and adjusting the system by the data feedback to meet specific purposes, such as: the whole system is dynamically maintained at a fixed acceleration value all the time.

The structural design of the whole system is a novel spiral ascending free light path. The design of the free light path and the matched measuring device are mutually linked, and the purposes of reading and adjusting the relative displacement change data generated in the rotation process by the rotary inertial motion system are jointly realized.

The free optical path of the rotary inertial motion system is composed of a bottom light splitting optical path and a top interference optical path, and a rotary inertial motion system structure similar to the principle of the fiber-optic gyroscope is formed under the combined action of the two parts. The supporting measuring mode of design in this system has adopted intelligent digital tachometer to measure and calculate rotatable circular platform's rotational speed to shoot and the image recording through the interference fringe behind the free light path of camera fixing on rotatory experiment circular platform, be convenient for carry out image analysis to the relative change data that take place in the system. The gyroscope has the advantages that the gyroscope can be used for figuratively and specifically measuring and calculating tiny rotation changes, is suitable for teaching and popular science demonstration, is small in size and high in precision, is more suitable for being combined into a gyroscope for measuring and controlling flight postures, and integrates experiment verification and demonstration.

The left side laser beam that diffraction laser instrument projected reflection prism 13 left surface passes through left front in proper order, in the left side, left back, just back, right back, the anticlockwise spiral lifting annular light path of reflector projects anticlockwise laser beam right front reflector 1 in the right side, and the right side laser beam that diffraction laser instrument projected reflection prism 13 right surface passes through right front in proper order, in the right side, right back, just back, left back, the clockwise spiral lifting annular light path of reflector projects clockwise laser beam left front reflector 7 in the left side. The anticlockwise spiral lifting annular light path is characterized in that an anticlockwise laser beam projected to the left side surface of the reflection prism 13 by the diffraction laser is lifted and reflected to the left middle reflector 6 through the left front reflector 7, and the anticlockwise laser beam is projected to the right front reflector 1 by the right middle reflector 2 through the midway reflector and is lifted and reflected by the right front reflector 1; clockwise spiral uplift annular light path is that diffraction laser projects the clockwise laser beam of reflection prism 13 right flank and rises through right front reflector 1 in proper order and reflects reflector 2, reflector 6 in the left side and projects clockwise laser beam to left front reflector 7 through midway reflector, is reflected out by left front reflector 7 lifting again.

The left front reflector 7 and the right front reflector 1 are both arranged in an outward-upward mode capable of lifting the light path. The left middle reflector, the left rear reflector, the right rear reflector and the right middle reflector are vertical reflectors for forming a midway circulating light path; before the reflector is arranged, the incident light is adjusted by the light shielding plate arranged at the position of the reflector to be capable of striking on the central axis of the light shielding plate, and the reflector is replaced and installed after the incident light is adjusted. In order to separate the laser beam into light rays which can be independently transmitted to two directions, the laser beam splitter uses the reflecting triple prism and achieves the purpose of splitting the light beams by utilizing the function of refracting the light rays by the triple prism. Since a single color laser is used in the experiment, the possibility that the prism will be dispersed is eliminated, and only two-directional refraction is possible. In order to ensure that the refracted light rays can have a large enough refraction angle, a reflective triangular prism with the apex angle of 90 degrees is further adopted. In the invention, the circular reflector is used to change the direction of light rays so as to achieve the aim of spiral rising of the light rays in a free light path. The direction of the reflected light in the free light path can be adjusted by using a support device with an adjustable reflector orientation.

Left and right front reflector 7, 1 set up the both sides that reflect triple prism 13 the place ahead bilateral symmetry on circular platform 10, about, reflector 6, 2 sets up the both sides of middle part bilateral symmetry on circular platform 10, left and right rear reflector 5, 3 sets up the both sides of diffraction laser instrument both sides bilateral symmetry on circular platform 10, just rear reflector 4 sets up the diffraction laser instrument dead astern above circular platform 10.

The diffraction laser is a longitudinal horizontal laser 11 with a vertical diaphragm 12 in front. The counterclockwise laser beam reflected by the left front reflector 7 and the clockwise laser beam reflected by the right front reflector 1 are reflected and transmitted by the reflection and transmission mirror 8 respectively, interfere with each other, pass through the beam expander 9 and irradiate on the ground glass observation screen 90. The interference fringe image finally formed by the free light path is presented in the form of a small light spot, and is inconvenient for observation and recording sampling, so that a beam expanding lens is arranged behind the reflection and transmission lens and in front of an observation screen of the interference fringe, and plays a role in expanding beams, and the image of the interference fringe is amplified to be convenient for observation and recording. Any mirror may be used to split the beam. The experiment used the laser technology, so the dielectric film mirror was used as a reflective transmissive mirror type beam splitter. The angle of incidence determines the angle of exit of the output beam, perhaps 45 ° being the most common, but of course other values are possible, and the angle of exit will affect the properties of the beam splitter. A wide range of power splitting ratios can be achieved by using different dielectric films. According to the practical situation in the experimental process, the method adopts the following steps that: 5 reflective transmissive mirror beam splitter.

The vertical horizontal laser is a laser pen which is vertically and horizontally arranged, and a vertical diaphragm which is arranged in front of or in front of the laser pen is used for restraining incident light, so that the interference of stray light is reduced, and the influence of irrelevant factors on an experiment is reduced. The vertical diaphragm performs a preliminary diffraction process on the incident light with a grating constant d = 300.0/mm. In order to keep the laser pen in a stable working state all the time in the experimental process, the support capable of adjusting the emergent light direction of the laser pen along with the actual situation is designed and manufactured according to the size of the laser pen and the height of light in a free light path, and a button locking device is further added on the laser pen in consideration of the instantaneity of a switch button of the laser pen, so that the laser pen can be always opened in the experimental process, and the emergent light of the laser pen can be stably emitted to a slit in the front. The laser used in the present invention, i.e. the laser transmitter, is a 303, 500nm green laser pointer with a key to lock the laser to avoid power loss.

A beam image camera or a video camera of the measuring system is arranged on the circular platform 10, and the beam image camera or the video camera is used for shooting two interfered beam images displayed by the ground glass observation screen 90. The three parallel circular platforms respectively provided with the optical device are arranged together in a mutually vertical mode to form a measuring part and a combined measuring and calculating part of the gyroscope, and the measuring and calculating part is used for measuring and controlling the attitude of the aircraft.

The circular platform matched with the intelligent tachometer is provided with a hinged support, and the beam image camera or the video camera is in communication connection with the intelligent tachometer through a wired or wireless communication mode to be used for measuring and calculating two interference beam images; or the intelligent tachometer is provided with a rotating speed display camera or a video camera for shooting and displaying the rotating speed in real time, the light beam image camera or the video camera and the rotating speed display camera or the video camera are in communication connection through a wireless or wired communication mode and are used for measuring and calculating two interference light beam images, and the design is used for teaching experiments. The computer is used for popular science demonstration after being matched with a wall-mounted display screen. When the device is used for popular science demonstration, a transparent dome glass cover for protecting all optical devices is arranged on the circular platform. The vertical diaphragm is a vertical diaphragm with a 300-line grating, and the transmission reflector is a 5:5 transmission reflector. The laser in the bottom layer light path is diffracted by the vertical diaphragm of the 300-line grating, is divided into two diffracted beams, and is respectively transmitted along opposite directions. Then the two beams of light are reflected by a plurality of groups of reflectors respectively and then emitted to a 5:5 transmission reflector to generate interference superposition. The matched measuring facility detects and captures the image of interference fringes generated by the whole rotary inertial motion system in the motion process, and analyzes corresponding data such as optical path difference and the like through the change image of the interference fringes in a certain time period. And further analyzing and processing the data according to the Sagnac effect, feeding the data back to the rotary inertial motion system, and adjusting the motion process of the rotary inertial motion system, so that the whole system achieves the aim of dynamic balance. The circular platform can be further provided with a speed-regulating rotary driving mechanism. The articulated support provided by the circular platform is preferably a slewing support. In the experimental process, a contact type rotating speed measuring mode is used, and the rotating speed of the experimental circular platform is calculated through the radius ratio between the synchronous wheel and the circular platform, wherein the synchronous wheel is in contact with the edge of the circular platform, and the intelligent tachometer is in contact with the edge of the circular platform.

In the second embodiment, as shown in fig. 3-4, the difference between the universal rotational inertial motion measurement system based on the diffractive spectroscopic reverse interference of the present invention and the first embodiment is: the diffraction laser is characterized in that a vertical diaphragm 12 is arranged on a light path between a longitudinal horizontal laser 11 and a reflective prism 13. The socket base plate of the reflector is screwed on the circular platform 10, a vertical base pipe is formed upwards on the socket base plate, and the vertical base pipe is inserted into the base part of the vertical supporting rod of the reflector and is fixed by a transverse fastening screw. The upper end of the vertical supporting rod is fixedly provided with a circular ring-shaped mirror frame of the left and right middle reflectors 6 and 2, the left and right rear reflectors 5 and 3 and the front and rear reflectors 4. The U-shaped hinged frame of the left and right front reflectors 7 and 1 is fixedly arranged at the upper end of the vertical supporting rod, and the U-shaped hinged frame is hinged with the circular mirror frames of the left and right front reflectors 7 and 1 through a cross shaft attached with a fastening screw. Therefore, the directions of all the reflectors are adjusted through the relative rotation of the vertical supporting rod and the vertical base tube, and the elevation angles of the left front reflector 7 and the right front reflector 1 at the two ends are adjusted through the relative rotation of the U-shaped hinged frame and the circular ring-shaped mirror frame. A vertical support is fixedly arranged on the circular platform 10, a U-shaped support of the longitudinal horizontal laser 11 is fixedly arranged on the vertical support through an adjustable screw, and end rings arranged at the front end and the rear end of the U-shaped support are respectively adjusted and fixed through a plurality of parallel adjustable fastening screws to penetrate through the horizontal laser 11 of the end ring. A three-disc vertical seat is fixedly arranged on the circular platform at a vertical interval, the front end part of an F-shaped support with two upward side arms is fixedly arranged on a middle disc of the three-disc vertical seat, the two side arms of the F-shaped support are provided with vertical diaphragms 12, and the vertical diaphragms 12 are extruded and fixed between the front end of a longitudinal screw and a front side arm by utilizing the longitudinal screw which penetrates through a rear side arm. The reflecting prism 13 is fixedly arranged on the top-layer disk of the three-disk vertical seat, and preferably, a shading block is arranged on the top-layer disk behind the reflecting prism 13. The socket base plate of the reflector is screwed on the front of the three-disk vertical seat on the circular platform 10, a vertical base pipe is manufactured upwards on the socket base plate, and the vertical base pipe is inserted into the inverted L-shaped vertical rod base part of the transmission reflector 8 and is fixed by a transverse fastening screw. The transmission reflector 8 is arranged at the cross arm end extending out of the upper end of the L-shaped vertical rod towards the center direction of the platform, the cross arm is preferably a transverse telescopic arm with adjustable length, and the extending direction of the cross arm and the height of the L-shaped vertical rod can be adjusted by loosening a transverse fastening screw. The front end of the cross arm is fastened with the rear part of the transmission reflector 8 through an adjustable screw, and the pitching angle of the transmission reflector 8 can be adjusted by loosening the adjustable screw. An inverted T-shaped seat is fixedly installed on the circular platform 10, a ground glass observation screen 90 is arranged at the upper end of a vertical rod of the inverted T-shaped seat, a transverse extending arm end of an L-shaped support is fixedly installed on a base plate of the inverted T-shaped seat, and a beam expanding lens 9 is arranged at an upper extending arm end of the L-shaped support. The vertical diaphragm is a vertical diaphragm with a 300-line grating, and the transmission reflector is a 5:5 transmission reflector. The laser in the bottom layer light path is diffracted by the vertical diaphragm of the 300-line grating, is divided into two diffracted beams, and is respectively transmitted along opposite directions. Then the two beams of light are reflected by a plurality of groups of reflectors respectively and then emitted to a 5:5 transmission reflector to generate interference superposition. The attitude measurement and control comprises the following steps: the matched measuring facility detects and captures the image of interference fringes generated by the whole rotary inertial motion system in the motion process, and analyzes corresponding data such as optical path difference and the like through the change image of the interference fringes in a certain time period. And further analyzing and processing the data according to the Sagnac effect, feeding the data back to the rotary inertial motion system, and adjusting the motion process of the rotary inertial motion system, so that the whole system achieves the aim of dynamic balance.

The specific experimental process is as follows: and adjusting the laser to be horizontal, enabling the laser emitted by the laser to vertically pass through the slit of the vertical diaphragm and be diffracted, and irradiating the diffracted central main laser on two isosceles side surfaces of the right-angle triple prism. Then adjusting each reflector arranged at the periphery of the experimental platform to enable the forward light and the backward light to completely wind a circle and finally irradiate on the projection reflector arranged above the right-angle triple prism. The transmission reflector changes the propagation direction of clockwise light, so that two beams of light propagated along the opposite direction in the top layer light path pass through the beam expander and then irradiate on the ground glass observation screen fixed in front of the transmission reflector. After the laser transmitter is started, a light beam image camera for shooting interference fringes on the installation experiment table and a rotating speed display camera for shooting rotating speed data on the intelligent digital tachometer are started. When the round rotatable experiment platform is rotated, the high-brightness laser parallel to the experiment platform can be observed to be emitted from the laser emitter, and the light beam irradiates on the grating vertically arranged on the laser and is diffracted by the grating. Positive and negative first-order diffraction fringes produced by the grating diffraction phenomenon can be further hit to two isosceles side surfaces of the right-angle triangular prism to be subjected to mirror reflection, the two reflected light rays after the mirror reflection are respectively transmitted along clockwise and anticlockwise directions, the light rays transmitted along clockwise sequentially pass through clockwise midway reflectors, and the light rays transmitted along anticlockwise are vice versa, namely transmitted along the sequence of the anticlockwise midway reflectors. And when the circular rotatable experiment platform stops rotating, the laser is firstly turned off, and then videos shot by the two cameras are stored. The rotation direction of the circular rotatable experiment platform is changed, the experiment is repeated, and a plurality of groups of photographic videos are shot. After the videos of all the experiment groups are shot and stored, the camera is taken down from the fixing frame, and the experiment videos are read and uploaded.

The measurement principle is as follows: as shown in fig. 5, at rest, the beam entering the system splits into two rays traveling in opposite directions, which return in phase after moving in opposite directions at the same speed. As shown in FIG. 6, when the interferometer is rotating, a stationary observer can see in the inertial reference frame that light will be launched into the interferometer from point M, while it is launched in the opposite direction at the same speed c; then during the time of transmission through the loop, the beam splitter will move to M^、The observer will now see that the rotating light rays in the same direction as the beam splitter movement will necessarily travel over more than one revolution, whereas the counter-rotating light rays must travel less than a full revolution. The path difference 2 Δl _vThe measurement can be performed by interferometric means. First, one basic point to be considered as a premise needs to be kept in mind: this is not only what an observer in the stationary inertial system finds, but also what an observer in the rotating system finds. This applies because the two rotating light rays propagating in opposite directions return to the same point at the beam splitter locationIn the principle of causal relationship: if two events occur at the same point in space, the time difference in which they occur is conserved in any reference frame (i.e., the first order ratio of v/c). Comparing the Sagnac effect with the well-known relativistic kinematics problem is interesting in practice, which explains that the simultaneity of events is not an absolute concept.

Consider further a single beam formed by two mirrors (M)₁And M₂) Fig. 7, as shown in the figure. Light is emitted from a light source S and emitted in opposite directions, respectively, through a beam M₁And M₂After reflection, the light rays in both directions return to the light source S at the same time. Now, if the system is moved laterally, as shown in FIG. 8, the viewer will observe that the light rays first contact the mirror M₁Then moves towards the incident ray, then another mirror M₂. The delay between these two events is substantially the same as the Sagnac delay, i.e. the perimeter of the circular path replaces the distance between the source and mirror, and the tangential velocity caused by the translation velocity rotation. However, in this Sagnac mode transition, both events occur at two different points, and the causal relationship principle no longer applies.

In summary, the bottom-layer light splitting optical path design: during the experiment, as shown in fig. 1, the laser horizontally placed emits laser light, and then the laser light passes through the vertical diaphragm placed in front of the triangular mirror and is diffracted. The diffracted 1-order stripes respectively hit the two side surfaces of the reflective triangular prism and are reflected. The reflected light rays respectively irradiate the right front reflector and the right front reflector, and then are reflected in the clockwise direction and the anticlockwise direction in sequence by virtue of the midway light path reflectors placed at proper angles, so that the light rays have a spiral rising trend (clockwise or anticlockwise), and two annular reflected light paths in the clockwise direction and the anticlockwise direction are formed. Designing a top-layer interference light path: namely, the top interference light path design of the free light path in the rotary inertial motion system, as shown in fig. 2, the light which is transmitted clockwise and counterclockwise in the bottom light path is further emitted to the transmission reflector placed at the top, the clockwise and counterclockwise light respectively pass through the reflection and transmission effects on the transmission reflector, and then the two beams of light interfere with each other and pass through the beam expander to irradiate on the ground glass observation screen. Meanwhile, in the design scheme of the matched measurement system, a camera is used for shooting the observation screen, and then the sampling of the interference image is completed, so that the further analysis is facilitated.

As shown in fig. 3-4, the laser source emits an initial beam that is diffracted by a vertical stop placed in front of the triangular mirror. The diffracted 1-order stripes respectively hit the two side surfaces of the reflective triangular prism and are reflected. The two reflected light beams respectively strike the left and right front reflectors with elevation angles on the left and right sides. The elevation angles of the left front reflector and the right front reflector enable the light path to show a spiral rising trend, the light path finally irradiates to the transmission reflector at the top layer, the light rays of the clockwise light path are reflected, the light rays of the anticlockwise light path are transmitted, and the light rays are converged into tail end light rays after passing through the transmission reflector.

By adopting the technical scheme, the universal rotary inertial motion measurement system based on the diffraction beam splitting reverse interference has the advantages that the micro rotary change image can be measured and calculated specifically, the system is suitable for teaching and popular science demonstration, and the advantages of small size and high precision are more suitable for being combined into a gyroscope for measuring and controlling the flight attitude, and the experimental verification and demonstration are integrated.