CN118565467A - Hybrid laser inertial navigation two-stage vibration isolation system - Google Patents
Hybrid laser inertial navigation two-stage vibration isolation system Download PDFInfo
- Publication number
- CN118565467A CN118565467A CN202410538853.4A CN202410538853A CN118565467A CN 118565467 A CN118565467 A CN 118565467A CN 202410538853 A CN202410538853 A CN 202410538853A CN 118565467 A CN118565467 A CN 118565467A
- Authority
- CN
- China
- Prior art keywords
- vibration isolation
- frame
- column
- vibration
- laser
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000002955 isolation Methods 0.000 title claims abstract description 137
- 238000005259 measurement Methods 0.000 claims abstract description 55
- 230000000712 assembly Effects 0.000 claims abstract description 17
- 238000000429 assembly Methods 0.000 claims abstract description 17
- 230000000149 penetrating effect Effects 0.000 claims abstract description 10
- 238000013016 damping Methods 0.000 claims description 28
- 229920001971 elastomer Polymers 0.000 claims description 6
- 229910000861 Mg alloy Inorganic materials 0.000 claims description 5
- 239000000956 alloy Substances 0.000 claims description 5
- 238000000034 method Methods 0.000 claims description 5
- 238000013461 design Methods 0.000 description 13
- 230000000694 effects Effects 0.000 description 9
- 239000000306 component Substances 0.000 description 5
- 230000003321 amplification Effects 0.000 description 4
- 230000008878 coupling Effects 0.000 description 4
- 238000010168 coupling process Methods 0.000 description 4
- 238000005859 coupling reaction Methods 0.000 description 4
- 238000009434 installation Methods 0.000 description 4
- 230000033001 locomotion Effects 0.000 description 4
- 238000003199 nucleic acid amplification method Methods 0.000 description 4
- 230000001133 acceleration Effects 0.000 description 3
- 230000006872 improvement Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 230000007246 mechanism Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000003068 static effect Effects 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 1
- 230000003044 adaptive effect Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 230000003139 buffering effect Effects 0.000 description 1
- 239000000969 carrier Substances 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000007774 longterm Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005457 optimization Methods 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 239000013598 vector Substances 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
- G01C21/10—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration
- G01C21/12—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning
- G01C21/16—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
- G01C21/10—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration
- G01C21/12—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning
- G01C21/16—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
- G01C21/166—Mechanical, construction or arrangement details of inertial navigation systems
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
- G01C21/10—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration
- G01C21/12—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning
- G01C21/16—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
- G01C21/18—Stabilised platforms, e.g. by gyroscope
Landscapes
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Automation & Control Theory (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Vibration Prevention Devices (AREA)
Abstract
The invention discloses a hybrid laser inertial navigation two-stage vibration isolation system, which solves the problems that the existing hybrid laser inertial navigation cannot meet the high-precision requirement of hybrid laser inertial navigation with a complex structure, faces the complex mechanical environment and has insufficient adjustment space and flexibility, and particularly comprises an inner frame sleeved on the periphery of a laser strapdown inertial frame, an outer frame sleeved on the periphery of the inner frame, a box body sleeved outside the outer frame, a plurality of outer vibration isolators arranged outside the box body, a plurality of inner vibration isolation assemblies arranged between the laser strapdown inertial frame and the outer frame and penetrating the inner frame, two first rotating shaft assemblies arranged between the inner frame and the outer frame, and two second rotating shaft assemblies arranged between the outer frame and the box body; the plurality of outer vibration isolators are uniformly distributed around the box body, and the plurality of inner vibration isolating components are uniformly and symmetrically distributed on the two opposite sides of the laser strapdown inertial measurement unit; the inner and outer two-stage vibration isolation can ensure the navigation precision of the hybrid laser inertial measurement unit.
Description
Technical Field
The invention relates to hybrid laser inertial navigation, in particular to a hybrid laser inertial navigation two-stage vibration isolation system.
Background
The hybrid laser inertial navigation system (called hybrid laser inertial navigation system for short) is a novel inertial navigation system, combines the characteristics of a strapdown inertial navigation system, a traditional platform structure and a rotary inertial navigation system, has the functions of self-alignment, self-calibration and self-detection of laser three-self-inertial navigation system, can isolate angular movement of an projectile body by utilizing a frame in the navigation process, and simultaneously carries out rotation modulation, and carries out effective separation and compensation on constant drift of an accelerometer and partial error systems of the gyroscope so as to improve the inertial navigation use precision under the long-endurance condition.
The IMU (namely the traditional laser gyro strapdown inertial measurement unit, short for laser strapdown inertial measurement unit) is an important component of the guidance control system, and has the main functions that: measuring components of angular velocity vectors of the projectile body on three coordinate axes of a projectile body coordinate system in real time by utilizing laser gyroscopes with three mutually orthogonal sensitive axes; measuring components of apparent acceleration of the mass center of the projectile on a projectile coordinate axis in real time by utilizing accelerometers with three mutually orthogonal sensitive axes; the digital circuit is used for forming control signals and guidance instructions to control the flight attitude of the aircraft, and the digital circuit plays an important role in the guidance precision of the aircraft. The platform type structure establishes a gyro stabilizing platform by introducing three rotating shafts to isolate angular movement of the carrier, so that navigation positioning accuracy is greatly improved. The platform type inertial measurement unit has the greatest advantages of high navigation precision compared with the laser strapdown inertial measurement unit, but has the defects of complex structure, large volume, heavy weight, poor reliability and high cost.
The hybrid laser inertial navigation system integrates a physical platform for isolating angular motion of a carrier, a strapdown attitude algorithm and a rotation modulation suppression error effect, and mainly focuses on new requirements of high-speed and high-dynamic carriers on high-precision inertial navigation, so that navigation positioning precision can be greatly improved, quick and accurate self-alignment can be realized, self-calibration under installation conditions can be realized, and purchase/maintenance cost can be obviously reduced. Besides the innovation of self navigation modes, the precision improvement brought by the hybrid laser inertial navigation system also needs to solve the adaptability of the inertial navigation system in complex environments. As a core component of the inertial navigation system, the stability of the working environment of the hybrid laser inertial navigation system directly relates to the navigation positioning precision of the aircraft. With the continuous improvement of the survivability and adaptability requirements of the aircraft to the real complex environment, the mechanical environment faced by the hybrid laser inertial measurement unit is worse, and particularly, the hybrid laser inertial measurement unit has wide frequency range and large acceleration in terms of vibration, so that the structure of the instrument equipment reaches a state of stress damage; on the other hand, the continuous improvement of the positioning precision of the aircraft requires that the hybrid laser inertial measurement unit provide more accurate navigation data, so that the complexity of the working environment and the output accuracy of the inertial measurement unit become key problems to be solved urgently by the hybrid laser inertial measurement unit, and the research on the vibration protection of the hybrid laser inertial measurement unit has important significance for improving the output precision of the inertial measurement unit and effectively working in a complex vibration environment.
The laser gyro senses the angular movement of the optical path relative to the inertial space by the Sagnac effect of the ring optical path, but due to the locking effect the ring laser has a lock area, causing the output signal to lock. Currently, the main method to overcome the latch-up effect is to use mechanical dithering offset frequency. For a laser gyro shake control circuit, the lower the input control voltage is than the saturation value, the larger the shake system control margin is, but in practical engineering application, when the laser gyro is mounted on an inertial unit to form a system together with other structural modules, the input voltage is saturated before the shake amplitude of the shake mechanism reaches an ideal value, so that the gyro cannot work normally. Therefore, for the vibration isolation system, it is also required to ensure that the laser gyro outputs a larger vibration amplitude with less vibration excitation energy, so as to ensure the output precision of the hybrid laser inertial measurement unit.
The traditional laser inertial measurement unit generally adopts a single-stage vibration isolation scheme, and for an extreme-free and complex conventional mechanical environment, the single-stage vibration isolation system can provide a certain input magnitude attenuation effect or improve the navigation precision of the inertial measurement unit by optimizing a navigation algorithm. It still suffers from two disadvantages:
The first and the single-stage vibration isolation systems are relatively simple in design, cannot meet the high-precision requirement of hybrid laser inertial navigation of a complex structure, face complex mechanical environment, and are insufficient in adjustment space and flexibility.
Secondly, the navigation algorithm needs long-term research and development, and adjustment and optimization cannot be carried out in a short term according to the requirements of the inertial measurement unit service environment.
Disclosure of Invention
The invention aims to provide a hybrid laser inertial navigation two-stage vibration isolation system, which aims to solve the technical problems that the existing hybrid laser inertial navigation cannot meet the high-precision requirement of hybrid laser inertial navigation with a complex structure, faces to complex mechanical environment, has insufficient adjustment space and flexibility, and a navigation algorithm cannot adjust and optimize in a short period according to the requirement of the use environment of an inertial navigation unit.
In order to achieve the above purpose, the invention adopts the following technical scheme:
The hybrid laser inertial navigation two-stage vibration isolation system is used for a laser strapdown inertial measurement unit, wherein the laser strapdown inertial measurement unit comprises four sides, and the laser strapdown inertial measurement units are parallel to each other; defining two sides parallel to each other as a first side and two sides parallel to each other as a second side;
the special feature is that:
the device comprises an inner frame sleeved on the periphery of a laser strap-down inertial measurement unit, an outer frame sleeved on the periphery of the inner frame, a box body sleeved outside the outer frame, a plurality of outer vibration isolators arranged outside the box body, and a plurality of inner vibration isolation assemblies arranged between the laser strap-down inertial measurement unit and the outer frame and penetrating through the inner frame;
The two side surfaces of the inner frame corresponding to the first side are respectively provided with a first rotating shaft assembly, and the two side surfaces of the outer frame corresponding to the second side are respectively provided with a second rotating shaft assembly; the axes of the two first rotating shaft assemblies are positioned on the same straight line; the axes of the two second rotating shaft assemblies are positioned on the same straight line; two ends of the first rotating shaft assembly are respectively and rotatably connected with the inner frame and the outer frame; two ends of the second rotating shaft assembly are respectively and rotatably connected with the outer frame and the box body;
the plurality of external vibration isolators are uniformly distributed around the box body and used for attenuating external input energy;
the plurality of inner vibration isolation assemblies are evenly and symmetrically distributed on two second sides of the laser strapdown inertial measurement unit;
The inner vibration isolation assembly comprises limit screws penetrating through corresponding through holes in the inner frame, limit bushings sleeved on screw rods of the limit screws and penetrating through the inner frame, and a first damping pad and a second damping pad sleeved on the limit bushings;
The screw head of the limit screw is positioned between the outer frame and the inner frame, a gap is arranged between the screw head and the outer frame, and the tail of the screw is vertically connected with the laser strapdown inertial measurement unit; the first damping pad is arranged between the laser strapdown inertial measurement unit and the inner frame; the second damping pad is arranged between the inner frame and the screw head of the limit screw.
Further, the inner vibration isolation assembly further comprises a first gasket and a second gasket;
The first gasket is sleeved outside the limiting bushing and is positioned between the laser strapdown inertial measurement unit and the first damping pad; the first gasket and the limiting bushing are integrally arranged;
The second gasket is sleeved outside the limiting bush, the outer ring of the second gasket is contacted with one end, far away from the inner frame, of the second damping pad, and the inner ring of the second gasket is embedded in the limiting bush and is arranged between the limiting bush and the screw head of the limiting screw.
Further, a first annular bulge is arranged on the end face, close to the inner frame, of the first damping pad; the first annular bulge is sleeved between the limiting bushing and the inner wall of the corresponding through hole on the inner frame;
A second annular bulge is arranged on the end face, close to the inner frame, of the second damping pad; the second annular bulge is sleeved between the limiting bushing and the inner wall of the corresponding through hole on the inner frame;
And a gap is arranged between the first annular protrusion and two adjacent end surfaces of the first annular protrusion.
Further, the number of the inner vibration isolation assemblies is eight.
Further, the outer vibration isolator comprises a lower mounting frame, an upper mounting frame, a first vibration isolation column, a second vibration isolation column and a third vibration isolation column;
The lower mounting frame comprises a lower mounting plate, and triangular columns and lower mounting columns which are vertically arranged on the upper surface of the lower mounting plate; the triangular column is provided with two vertical faces which are perpendicular to each other, and a first vertical face and a second vertical face are respectively arranged;
The upper mounting frame comprises an upper mounting plate which is parallel to the lower mounting plate and fixedly connected with the box body, and a first vertical plate, a second vertical plate and an upper mounting column which are respectively and vertically arranged on the lower surface of the upper mounting plate;
The first vibration isolation column, the second vibration isolation column and the third vibration isolation column are distributed in a mutually perpendicular and orthogonal mode;
The lower end of the first vibration isolation column is coaxially connected with the lower mounting column, and the upper end of the first vibration isolation column is coaxially connected with the upper mounting column;
One end of the second vibration isolation column is vertically connected with the first vertical plate, and the other end of the second vibration isolation column is vertically connected with the first vertical surface;
one end of the third vibration isolation column is vertically connected with the second vertical plate, and the other end of the third vibration isolation column is vertically connected with the second vertical surface;
and a gap is arranged between the upper end of the triangular column and the upper mounting plate.
Further, the outer vibration isolator further comprises a first buffer block, a second buffer block and a third buffer block;
The first buffer block is arranged at the top of the triangular column, and a gap is arranged between the first buffer block and the upper mounting plate;
The second buffer block is arranged between the first vertical face and the first vertical plate, one end of the second buffer block is fixedly connected with the first vertical face, and a gap is arranged between the other end of the second buffer block and the first vertical plate;
the third buffer block is arranged between the second vertical face and the second vertical plate, one end of the third buffer block is fixedly connected with the second vertical face, and a gap is arranged between the other end of the third buffer block and the second vertical plate.
Further, the first mounting ring is sleeved outside the box body and used for being connected with an external structure;
a plurality of first mounting seats are uniformly distributed on the first mounting ring around the circumference of the first mounting ring; each first mounting seat is correspondingly provided with an external vibration isolator;
The lower mounting plate is fixedly connected with the first mounting seat;
The upper mounting plate is fixedly connected with the outer wall of the box body through an L-shaped bracket.
Further, the first vibration isolation column, the second vibration isolation column and the third vibration isolation column are all rubber columns;
the first buffer block, the second buffer block and the third buffer block are all made of rubber;
the first mounting ring and the first mounting seat are made of magnesium alloy materials.
Further, the outer vibration isolator is a T-shaped vibration isolator;
the upper end and the lower end of the T-shaped vibration isolator are respectively and fixedly connected with the box body.
Further, the device also comprises a second mounting ring which is sleeved outside the box body and is used for being connected with an external structure;
A plurality of second mounting seats are uniformly distributed on the second mounting ring around the circumference of the second mounting ring, and each second mounting seat is provided with a T-shaped vibration isolator;
the lower end of the T-shaped vibration isolator is fixedly connected with the second mounting seat, and the upper end of the T-shaped vibration isolator is fixedly connected with the outer wall of the box body through the L-shaped bracket.
The invention has the beneficial effects that:
1. The invention adopts the inner vibration isolation assembly and the outer vibration isolator to realize inner and outer two-stage vibration isolation, and the outer vibration isolator mainly attenuates the external input energy, so that the good working state of the hybrid laser strapdown inertial measurement unit under various complex mechanical environments can be ensured; the inner vibration isolation can ensure the vibration characteristic of the laser gyro in the laser strapdown inertial measurement unit on one hand, and can ensure the navigation precision of the hybrid laser inertial measurement unit by coaction with the outer vibration isolator on the other hand.
2. The external vibration isolator provided by the invention adopts the upper and lower mounting frames to mount three mutually perpendicular and orthogonal vibration isolation columns, so that a three-way vibration isolation function is formed, the whole structural design is ingenious, and the vibration isolation can be realized and the three-way rigidity can be ensured.
3. The three buffer cushions are also arranged in the external vibration isolator, so that the vibration isolator can play a role in buffering and protecting the vibration isolation columns when the overload is large or the three mutually perpendicular and orthogonal vibration isolation columns are subjected to limit deformation.
4. According to the invention, two-stage vibration isolation parameters can be adjusted by changing the sizes or materials of the inner vibration isolation assembly and the outer vibration isolator, the coupling frequency of the vibration isolator is changed, the dynamic characteristics of the IMU are ensured, and the navigation precision of the hybrid laser inertial measurement unit is further improved.
5. The invention adopts the magnesium alloy material to manufacture the first mounting ring and the first mounting seat, and the material has high elastic modulus and good vibration absorption effect, and can further improve vibration isolation efficiency.
Drawings
Fig. 1 is a schematic structural diagram of a hybrid laser inertial navigation two-stage vibration isolation system according to an embodiment of the present invention;
FIG. 2 is a top view of FIG. 1;
Fig. 3 is a schematic structural view of an inner frame and an inner vibration isolation assembly according to a first embodiment of the present invention;
figure 4 is a cross-sectional view of an internal vibration isolation assembly according to a first embodiment of the present invention;
Figure 5 is a schematic view of the structure of an outer vibration isolator in accordance with an embodiment of the present invention;
Figure 6 is a schematic view of a partial structure of an outer vibration isolator according to a first embodiment of the present invention;
Fig. 7 is a schematic structural diagram of a second embodiment of a hybrid laser inertial navigation two-stage vibration isolation system according to the present invention.
Reference numerals:
1-laser strapdown inertial frame, 2-inner frame, 3-outer frame, 4-box, 5-outer isolator, 51-lower mounting frame, 511-lower mounting plate, 512-triangular post, 5121-first vertical face, 5122-second vertical face, 513-lower mounting post, 52-upper mounting frame, 521-upper mounting plate, 522-first riser, 523-second riser, 524-upper mounting post, 53-first vibration isolation post, 54-second vibration isolation post, 55-third vibration isolation post, 6-inner vibration isolation assembly, 61-stop screw, 62-stop bushing, 63-first damping pad, 631-first annular boss, 64-second damping pad, 641-second annular boss, 65-first washer, 66-second washer, 7-first rotation axis assembly, 8-second rotation axis assembly, 9-first mounting ring, 91-first mount, 10-T vibration isolator, 11-second mount ring, 111-second mount, 12-L bracket.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is apparent that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
Embodiment one:
The embodiment aims at the IMU, an inner vibration isolation system is arranged in the box body, an outer vibration isolation system is designed outside the box body, the coupling frequency of the vibration isolator is changed, the dynamic characteristics of the IMU are ensured, the navigation precision of the inertial measurement unit is improved, and the specific structure is as follows:
As shown in fig. 1, a hybrid laser inertial navigation two-stage vibration isolation system is used for a laser strapdown inertial measurement unit 1; the laser strapdown inertial measurement unit 1 comprises four sides, and the two sides are parallel to each other; wherein two mutually parallel sides are defined as first sides and the other two mutually parallel sides are defined as second sides.
The two-stage vibration isolation system comprises an inner frame 2 sleeved on the periphery of a laser strapdown inertial unit 1, an outer frame 3 sleeved on the periphery of the inner frame 2, a box body 4 sleeved outside the outer frame 3, four outer vibration isolators 5 arranged outside the box body 4, and eight inner vibration isolation assemblies 6 arranged between the laser strapdown inertial unit 1 and the outer frame 3 and penetrating through the inner frame 2; the first mounting ring 9 is sleeved outside the box body 4, made of magnesium alloy materials and used for being connected with an external structure.
As shown in fig. 2, two side surfaces of the inner frame 2 corresponding to the first side are respectively provided with a first rotating shaft assembly 7, and two side surfaces of the outer frame 3 corresponding to the second side are respectively provided with a second rotating shaft assembly 8; the axes of the two first rotating shaft assemblies 7 are positioned on the same straight line; the axes of the two second rotating shaft assemblies 8 are positioned on the same straight line; the two ends of the first rotating shaft assembly 7 are respectively rotatably connected with the inner frame 2 and the outer frame 3; the two ends of the second rotating shaft assembly 8 are respectively and rotatably connected with the outer frame 3 and the box body 4.
As shown in fig. 3, eight internal vibration isolation assemblies 6 are evenly and symmetrically distributed on two second sides of the laser strapdown inertial measurement unit 1.
As shown in fig. 4, the inner vibration isolation assembly 6 includes a limit screw 61 penetrating into a corresponding through hole on the inner frame 2, a limit bushing 62 sleeved on a screw rod of the limit screw 61 and penetrating into the inner frame 2, and a first damping pad 63 and a second damping pad 64 sleeved on the limit bushing 62; also included are a first gasket 65 and a second gasket 66; the screw head of the limit screw 61 is positioned between the outer frame 3 and the inner frame 2, a gap is arranged between the limit screw and the outer frame 3, and the tail of the screw is vertically connected with the laser strapdown inertial measurement unit 1; the first damping pad 63 is arranged between the laser strapdown inertial frame 1 and the inner frame 2; the first damping pad 63 is provided with a first annular protrusion 631 on an end face near the inner frame 2; the first annular protrusion 631 is sleeved between the limit bushing 62 and the inner wall of the corresponding through hole on the inner frame 2; the second damping pad 64 is arranged between the inner frame 2 and the screw head of the limit screw 61; the second damping pad 64 is provided with a second annular protrusion 641 on an end surface near the inner frame 2; the second annular protrusion 641 is sleeved between the limit bushing 62 and the inner wall of the corresponding through hole on the inner frame 2; a gap is provided between the adjacent end surfaces of the first annular projection 631 and the first annular projection 641. The first washer 65 is sleeved outside the limiting bushing 62 and is positioned between the laser strapdown inertial measurement unit 1 and the first damping pad 63; the first washer 65 is integrally arranged with the limit bushing 62; the second washer 66 is sleeved outside the limiting bush 62, the outer ring of the second washer is contacted with one end, far away from the inner frame 2, of the second damping pad 64, and the inner ring of the second washer is embedded in the limiting bush 62 and is arranged between the limiting bush 62 and the screw head of the limiting screw 61.
Four first mounting seats 91 made of magnesium alloy materials are uniformly distributed on the first mounting ring 9 around the circumference of the first mounting ring; each first mounting seat 91 is correspondingly provided with an external vibration isolator 5; four external vibration isolators 5 are respectively arranged at four corners of the outer side of the box body 4 and used for attenuating external input energy.
As shown in fig. 5, each of the outer vibration isolators 5 includes a lower mount 51, an upper mount 52, a first vibration isolation column 53, a second vibration isolation column 54, and a third vibration isolation column 55, respectively; the first vibration isolation column 53, the second vibration isolation column 54, and the third vibration isolation column 55 are rubber columns; further comprising a first buffer block 56, a second buffer block 57 and a third buffer block 58; the first buffer block 56, the second buffer block 57 and the third buffer block 58 are all made of rubber; the lower mounting bracket 51 includes a lower mounting plate 511 and triangular columns 512 and lower mounting columns 513 vertically provided on the upper surface of the lower mounting plate 511; the triangular prism 512 has two vertical faces perpendicular to each other, a first vertical face 5121 and a second vertical face 5122; the upper mounting frame 52 includes an upper mounting plate 521 parallel to the lower mounting plate 511 and fixedly connected to the case 4, and a first riser 522, a second riser 523, and an upper mounting post 524 vertically mounted on the lower surface of the upper mounting plate 521, respectively; as shown in fig. 6, the first vibration isolation column 53, the second vibration isolation column 54, and the third vibration isolation column 55 are distributed in a mutually perpendicular and orthogonal manner; the lower end of the first vibration isolation column 53 is coaxially connected with the lower mounting column 513, and the upper end is coaxially connected with the upper mounting column 524; one end of the second vibration isolation pillar 54 is vertically connected with the first riser 522, and the other end is vertically connected with the first elevation 5121; one end of the third vibration isolation column 55 is vertically connected with the second riser 523, and the other end is vertically connected with the second vertical face 5122; a gap is provided between the upper end of the triangular prism 512 and the upper mounting plate 521. The first buffer block 56 is disposed at the top of the triangular column 512 and has a gap with the upper mounting plate 521; the second buffer block 57 is disposed between the first vertical face 5121 and the first vertical plate 522, and has one end fixedly connected to the first vertical face 5121 and the other end having a gap with the first vertical plate 522; the third buffer block 58 is disposed between the second vertical surface 5122 and the second vertical plate 523, and has one end fixedly connected to the second vertical surface 5122 and the other end having a gap with the second vertical plate 523. The lower mounting plate 51 is fixedly connected with the first mounting seat 91; the upper mounting plate 51 is fixedly connected with the outer wall of the box body 4 through the L-shaped bracket 12. The external vibration isolator 5 adopts a three-way vibration isolator mode, and can ensure the three-way equal rigidity of the external vibration isolation system.
The design thought of the hybrid laser inertial navigation two-stage vibration isolation system is as follows:
And (3) designing an internal vibration isolation system:
1. Confirming layout
A. The internal vibration isolation system is supported in eight points in space.
In general, the optimal vibration isolation design of the inertial unit is to meet the premise of the installation accuracy of the inertial unit, wherein the linear vibration resonance frequency is as small as possible and the angular vibration resonance frequency is as large as possible. To meet this requirement, a structural form with a large frequency ratio in the same space should be selected as much as possible, such as a space eight-point support arrangement.
And b, designing three-in-one design, namely, overlapping the centroid and the mass center of the IMU with the vibration isolation center.
The eccentricity of the structure causes an increase in the equivalent moment of inertia, resulting in a decrease in the ratio of the angular resonant frequency to the linear resonant frequency, and in the case of a given isolator linear resonant frequency, a consequent decrease in the angular resonant frequency. Therefore, the centroid and the centroid of the IMU should be coincident with the vibration isolation center as much as possible, avoiding line and angular frequency coupling.
2. Vibration isolator selection
A. The payload and operating frequency are determined.
Primarily estimating the mass of the vibration isolation object according to all the components, and taking the mass as the effective static load of the vibration isolation system; the natural frequency, which is the resonance frequency of the vibration isolation system, is determined based on the frequency characteristic requirements of the main components and the frequency characteristic requirements of the external structure other than the vibration isolation system. Vibrations at natural frequencies are typically passively amplified, so the determination of the natural frequencies of the isolator follows the following principles: avoiding the natural frequency of the product structure and the instrument element; the natural frequency of the vibration isolator should be at a place where the environmental vibration is small; the natural frequency of the vibration isolator enables the angular frequency to meet the requirements of an aircraft attitude control system;
b. And determining the transmissibility of the vibration isolator.
Typically the amplification factor at the resonance of the isolator is determined to be between 2.5 and 3.5, which can be suitably relaxed if the isolator is limited by materials, process, environmental conditions.
From the aspect of the inertial navigation device, it is extremely important to ensure the accuracy of gyroscopes and accelerometers. Because the resonance frequency of the gyroscope and the accelerometer is outside the resonance area, the smaller the amplification factor of resonance is, the smaller the influence on the gyroscope and the accelerometer is. Therefore, a method of avoiding too high amplification at resonance and too large influence on vibration in the low frequency band is to select a low peak vibration isolator. However, selecting a low peak isolator affects the high frequency isolation of the isolator, and therefore, the isolator resonant transmission should be selected to be within a reasonable range of intervals.
And (3) designing an external vibration isolation system:
1. Confirming layout
A. the external vibration isolation system adopts a plane four-point supporting mode.
In general, when the external vibration isolation system is designed for structural layout, the external structure installation interface needs to be considered, so that a planar four-point support mode is generally adopted and uniformly distributed around the box body.
B. four-in-one design.
The centroid of the hybrid laser inertial measurement unit should coincide with the centroid and vibration isolation center of the external vibration isolation system and at the same time coincide with the internal vibration isolation center, so that on one hand, line and angular frequency coupling is avoided, and on the other hand, additional angular rate amplification caused by structural eccentricity is reduced.
2. Vibration isolator selection
A. The payload and operating frequency are determined.
If the external vibration (especially high-frequency magnitude) and the impact input magnitude are smaller, the frequency of the vibration isolator should be as high as possible under the premise of ensuring the normal operation of the laser gyro so as to ensure the angular frequency characteristic requirement; if the external vibration (especially the high frequency level) and the impact input level are larger, the vibration isolator frequency should be lower and better on the premise of ensuring the static and dynamic installation precision of the laser gyro, but the external acceleration condition should be considered, and meanwhile, the vibration isolator frequency should be within the total required range.
B. Three-way equal stiffness design.
In order to ensure that the vibration frequency, deformation and vibration isolation effect of the hybrid laser inertial measurement unit are basically consistent under the external vibration excitation in three directions, the vibration isolation system is required to be designed with three-way equal rigidity. The outer vibration isolation system can be arranged at four points in space, and each vibration isolator is assembled with the upper mounting frame and the lower mounting frame by three mutually perpendicular and orthogonal vibration isolation columns, wherein the center of the connecting shaft of the upper mounting frame passes through the centers of the three pairs of mutually perpendicular and orthogonal vibration isolation columns, and thus three-way equal rigidity is realized through three-way vibration isolation.
Two-stage vibration isolation system adaptability design:
1. adaptive design of two-stage vibration isolation system
A. the internal vibration isolation frequency is reduced, and the vibration performance of the laser gyro is ensured, so that the output precision of the inertial measurement unit is ensured.
Under the condition of a certain IMU structural design, the laser gyro can output larger shaking amplitude by reducing the internal vibration isolation frequency, so that the output precision of the inertial measurement unit is ensured.
B. The external vibration isolation frequency is reduced, and the attenuation efficiency is improved.
The hybrid laser inertial measurement unit two-stage vibration isolation system attenuates the input energy of the whole machine through the external vibration isolation system so as to ensure that the IMU has a good working environment. Therefore, the external vibration isolation system is required to have good energy attenuation effect, so that the mechanical environment energy transmitted to the IMU through the box body and the indexing mechanism is as small as possible, and the output precision of the inertial unit is ensured.
C. and the frequency difference design of the two-stage vibration isolation system is realized.
Because the inner vibration isolation system and the outer vibration isolation system of the hybrid laser inertial measurement unit have respective resonant frequencies, when the frequencies are close, under the condition of vibration environment, the resonant peaks of the two-stage vibration isolation system are coupled, namely resonance occurs in a local frequency band range, so that the vibration magnitude is amplified, and the output precision of the IMU is affected. Therefore, the resonant frequencies of the internal and external vibration isolation systems of the laser three-self inertial measurement unit are required to be designed differently, so that the coupled resonance is avoided, and the energy attenuation effect of the vibration isolation system is ensured.
The hybrid laser inertial navigation two-stage vibration isolation system formed based on the design thought can adapt to more complex and harsher mechanical environment conditions by applying the two-stage vibration isolation system, and can ensure the output precision of the inertial measurement unit under the environment conditions of large magnitude and large overload; and under the same mechanical environment condition, the vibration isolation system is more convenient to adjust, so that the inertial measurement unit can be optimized and the output precision is improved.
Embodiment two:
as shown in fig. 7, this embodiment is substantially the same as the first embodiment except that the outer vibration isolator 5 is a T-type vibration isolator 10; the second mounting ring 11 is sleeved outside the box body 4, four second mounting seats 111 are uniformly distributed on the second mounting ring 11 around the circumferential direction of the second mounting ring, and each second mounting seat 111 is provided with a T-shaped vibration isolator 10; the lower end of the T-shaped vibration isolator 10 is fixedly connected with the second mounting seat 111, and the upper end of the T-shaped vibration isolator is fixedly connected with the outer wall of the box body 4 through the L-shaped bracket 12. The invention can realize three-dimensional equal rigidity and light and miniaturized design by designing the size of the damping pad and adjusting the parameters of the damping pad.
The foregoing is merely illustrative of specific embodiments of the present invention, and the scope of the present invention is not limited thereto, but any changes or substitutions within the technical scope of the present invention should be covered by the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.
Claims (10)
1. The hybrid laser inertial navigation two-stage vibration isolation system is used for a laser strapdown inertial measurement unit (1), wherein the laser strapdown inertial measurement unit (1) comprises four sides, and the laser strapdown inertial measurement units are parallel to each other; defining two sides parallel to each other as a first side and two sides parallel to each other as a second side;
The method is characterized in that:
The laser strapdown inertial measurement unit comprises an inner frame (2) sleeved on the periphery of a laser strapdown inertial measurement unit (1), an outer frame (3) sleeved on the periphery of the inner frame (2), a box body (4) sleeved outside the outer frame (3), a plurality of outer vibration isolators (5) arranged outside the box body (4), and a plurality of inner vibration isolation assemblies (6) arranged between the laser strapdown inertial measurement unit (1) and the outer frame (3) and penetrating through the inner frame (2);
The two side surfaces of the inner frame (2) corresponding to the first side are respectively provided with a first rotating shaft assembly (1), and the two side surfaces of the outer frame (3) corresponding to the second side are respectively provided with a second rotating shaft assembly (8); the axes of the two first rotating shaft assemblies (7) are positioned on the same straight line; the axes of the two second rotating shaft assemblies (8) are positioned on the same straight line; two ends of the first rotating shaft assembly (7) are respectively and rotatably connected with the inner frame (2) and the outer frame (3); two ends of the second rotating shaft assembly (8) are respectively and rotatably connected with the outer frame (3) and the box body (4);
The plurality of external vibration isolators (5) are uniformly distributed around the box body (4) and used for attenuating external input energy;
The plurality of inner vibration isolation assemblies (6) are evenly and symmetrically distributed on two second sides of the laser strapdown inertial measurement unit (1);
The inner vibration isolation assembly (6) comprises limit screws (61) penetrating through corresponding through holes in the inner frame (2), limit bushings (62) sleeved on screw rods of the limit screws (61) and penetrating through the inner frame (2), first damping pads (63) and second damping pads (64) sleeved on the limit bushings (62);
The screw head of the limit screw (61) is positioned between the outer frame (3) and the inner frame (2), a gap is arranged between the screw head and the outer frame (3), and the tail of the screw is vertically connected with the laser strapdown inertial measurement unit (1); the first damping pad (63) is arranged between the laser strapdown inertial measurement unit (1) and the inner frame (2); the second damping pad (64) is arranged between the inner frame (2) and the screw head of the limit screw (61).
2. The hybrid laser inertial navigation two-stage vibration isolation system of claim 1, wherein: the inner vibration isolation assembly (6) further comprises a first gasket (65) and a second gasket (66);
the first gasket (65) is sleeved outside the limiting bushing (62) and is positioned between the laser strapdown inertial measurement unit (1) and the first damping pad (63); the first gasket (65) and the limiting bushing (62) are integrally arranged;
the second gasket (66) is sleeved outside the limiting bushing (62), the outer ring of the second gasket is contacted with one end, far away from the inner frame (2), of the second damping pad (64), and the inner ring of the second gasket is embedded in the limiting bushing (62) and is arranged between the limiting bushing (62) and the screw head of the limiting screw (61).
3. The hybrid laser inertial navigation two-stage vibration isolation system of claim 2, wherein: a first annular bulge (631) is arranged on the end face, close to the inner frame (2), of the first damping pad (63); the first annular bulge (631) is sleeved between the limit bushing (62) and the inner wall of the corresponding through hole on the inner frame (2);
A second annular protrusion (641) is arranged on the end surface of one end, close to the inner frame (2), of the second damping pad (64); the second annular protrusion (641) is sleeved between the limit bushing (62) and the inner wall of the corresponding through hole on the inner frame (2);
A gap is arranged between the first annular protrusion (631) and two adjacent end surfaces of the first annular protrusion (641).
4. A hybrid laser inertial navigation two-stage vibration isolation system according to claim 3, characterized in that: the number of the inner vibration isolation assemblies (6) is eight.
5. The hybrid laser inertial navigation two-stage vibration isolation system according to any one of claims 1-4, wherein: the outer vibration isolator (5) comprises a lower mounting frame (51), an upper mounting frame (52), a first vibration isolation column (53), a second vibration isolation column (54) and a third vibration isolation column (55);
the lower mounting frame (51) comprises a lower mounting plate (511), and triangular columns (512) and lower mounting columns (513) which are vertically arranged on the upper surface of the lower mounting plate (511); the triangular column (512) is provided with two vertical faces which are perpendicular to each other, a first vertical face (5121) and a second vertical face (5122) respectively;
The upper mounting frame (52) comprises an upper mounting plate (521) which is parallel to the lower mounting plate (511) and fixedly connected with the box body (4), and a first vertical plate (522), a second vertical plate (523) and an upper mounting column (524) which are respectively and vertically arranged on the lower surface of the upper mounting plate (521);
The first vibration isolation column (53), the second vibration isolation column (54) and the third vibration isolation column (55) are distributed in a mutually perpendicular and orthogonal mode;
The lower end of the first vibration isolation column (53) is coaxially connected with the lower mounting column (513), and the upper end of the first vibration isolation column is coaxially connected with the upper mounting column (524);
One end of the second vibration isolation column (54) is vertically connected with the first vertical plate (522), and the other end of the second vibration isolation column is vertically connected with the first vertical surface (5121);
One end of the third vibration isolation column (55) is vertically connected with the second vertical plate (523), and the other end of the third vibration isolation column is vertically connected with the second vertical surface (5122);
a gap is arranged between the upper end of the triangular column (512) and the upper mounting plate (521).
6. The hybrid laser inertial navigation two-stage vibration isolation system of claim 5, wherein: the outer vibration isolator (5) further comprises a first buffer block (56), a second buffer block (57) and a third buffer block (58);
The first buffer block (56) is arranged at the top of the triangular column (512), and a gap is arranged between the first buffer block and the upper mounting plate (521);
The second buffer block (57) is arranged between the first vertical face (5121) and the first vertical plate (522), one end of the second buffer block is fixedly connected with the first vertical face (5121), and a gap is arranged between the other end of the second buffer block and the first vertical plate (522);
The third buffer block (58) is arranged between the second vertical face (5122) and the second vertical plate (523), one end of the third buffer block is fixedly connected with the second vertical face (5122), and a gap is arranged between the other end of the third buffer block and the second vertical plate (523).
7. The hybrid laser inertial navigation two-stage vibration isolation system of claim 6, wherein: the first mounting ring (9) is sleeved outside the box body (4) and is used for being connected with an external structure;
A plurality of first mounting seats (91) are uniformly distributed on the first mounting ring (9) around the circumference of the first mounting ring; each first mounting seat (91) is correspondingly provided with an outer vibration isolator (5);
The lower mounting plate (51) is fixedly connected with the first mounting seat (91);
The upper mounting plate (51) is fixedly connected with the outer wall of the box body (4) through the L-shaped bracket (12).
8. The hybrid laser inertial navigation two-stage vibration isolation system of claim 7, wherein:
The first vibration isolation column (53), the second vibration isolation column (54) and the third vibration isolation column (55) are all rubber columns;
The first buffer block (56), the second buffer block (57) and the third buffer block (58) are all made of rubber;
the first mounting ring (9) and the first mounting seat (91) are made of magnesium alloy materials.
9. The hybrid laser inertial navigation two-stage vibration isolation system according to any one of claims 1-4, wherein: the outer vibration isolator (5) is a T-shaped vibration isolator (10);
the upper end and the lower end of the T-shaped vibration isolator (10) are respectively and fixedly connected with the box body (4).
10. The hybrid laser inertial navigation two-stage vibration isolation system of claim 9, wherein: the second mounting ring (11) is sleeved outside the box body (4) and is used for being connected with an external structure;
a plurality of second mounting seats (111) are uniformly distributed on the second mounting ring (11) around the circumference of the second mounting ring, and each second mounting seat (111) is provided with a T-shaped vibration isolator (10);
The lower end of the T-shaped vibration isolator (10) is fixedly connected with the second mounting seat (111), and the upper end of the T-shaped vibration isolator is fixedly connected with the outer wall of the box body (4) through the L-shaped bracket (12).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410538853.4A CN118565467A (en) | 2024-04-30 | 2024-04-30 | Hybrid laser inertial navigation two-stage vibration isolation system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410538853.4A CN118565467A (en) | 2024-04-30 | 2024-04-30 | Hybrid laser inertial navigation two-stage vibration isolation system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118565467A true CN118565467A (en) | 2024-08-30 |
Family
ID=92477354
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410538853.4A Pending CN118565467A (en) | 2024-04-30 | 2024-04-30 | Hybrid laser inertial navigation two-stage vibration isolation system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN118565467A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN121162640A (en) * | 2025-11-21 | 2025-12-19 | 上海大学 | Double-layer flexible vibration isolation device for ship sonar system |
-
2024
- 2024-04-30 CN CN202410538853.4A patent/CN118565467A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN121162640A (en) * | 2025-11-21 | 2025-12-19 | 上海大学 | Double-layer flexible vibration isolation device for ship sonar system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4033541A (en) | Torque rejection soft mounted platform | |
| US6029959A (en) | Semi-active vibration isolator and fine positioning mount | |
| US20160097793A1 (en) | Micro inertial measurement system | |
| CN102607549B (en) | Spatially diagonal damping fiber-optic gyroscope IMU (Inertial Measurement Unit) body | |
| JP2005504251A (en) | Small vibration isolation system for inertial sensor assembly | |
| US12038282B2 (en) | MEMS single-axis gyroscope | |
| US20050204817A1 (en) | Three axis active magnetic levitation for inertial sensing systems | |
| CN116221314A (en) | A damping shock absorber and self-absorbing vibration mechanical shake laser gyro inertial measurement unit | |
| CN118565467A (en) | Hybrid laser inertial navigation two-stage vibration isolation system | |
| KR20180101181A (en) | Vibration damping mount | |
| CN105889385A (en) | Compression spring type six-degree-of-freedom quasi-zero stiffness vibration isolator and design method thereof | |
| US3952980A (en) | Translatory shock absorber for attitude sensors | |
| CN108036781B (en) | Frequency band self-adaptive anti-vibration gyroscope | |
| US6871561B2 (en) | Isolator and assembly configuration | |
| CN112765740A (en) | Method for determining buffering effect of hanging basket type buffering device in design stage | |
| US6401535B1 (en) | Active cover accelerometer | |
| CN210400406U (en) | Triaxial laser gyro combination H type rack device | |
| JPS6110139A (en) | Vibration isolator | |
| US11339850B2 (en) | Orthogonally-optimized vibration isolation | |
| US5348266A (en) | Reduced horizontal stiffness vibration isolation system | |
| CN107339364A (en) | The shock mitigation system and its installation method of the used group of carrier rocket optical fiber | |
| GB2271422A (en) | Compensated inertial guidance system | |
| CN210108376U (en) | Corner-free buffer platform of marine strapdown inertial navigation system | |
| CN110763230A (en) | A table body structure and inertial measurement device for installing inertial instruments | |
| CN112709780B (en) | Novel vibration isolator with hinge type angular displacement-free mechanism |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |