Adaptive inertial navigation assembly flexure system

Abstract

The utility model discloses a kind of self-adapting inertial navigation assembly elastic clamp systems, the system includes double-layer adjusting platform module, elastic clamp module and laser alignment module, the double-layer adjusting platform module includes upper layer platform and lower layer platform, the lower layer platform bottom is provided with the connecting screw hole adapted with rate turntable, the upper layer platform is slidably connected with lower layer platform by slide rail assembly, the elastic clamp module is carried on upper layer platform;The elastic clamp module includes shape memory alloy spring limiting device and carbon fiber-ceramic composite material clamp body, the shape memory alloy spring limiting device is movably arranged on upper layer platform, the carbon fiber-ceramic composite material clamp body is fixedly arranged on upper layer platform;The laser alignment module includes laser emission module and CMOS sensing component, the laser emission module and CMOS sensing component are installed on lower layer platform.The utility model improves production efficiency, reduces artificial error.

Description

Technical Field

[0001] This utility model relates to an adaptive inertial navigation assembly elastic clamp system, belonging to the field of inertial navigation assembly scaling nonlinear testing technology. Background Technology

[0002] An Inertial Measurement Unit (IMU) is an electronic device used to measure and report the three fundamental linear motions (acceleration) and three fundamental angular motions (angular velocity) of an object. Regardless of size, from ultra-small MEMS sensors to high-precision laser gyroscopes, IMUs operate on the principle of inertial laws. An IMU typically includes a set of accelerometers and gyroscopes; these are the core components of an inertial system and the main factors affecting its performance. IMUs are widely used in scenarios requiring autonomous positioning, attitude control, or motion tracking, specifically including: Aerospace and Defense: Attitude control and navigation of aircraft (aircraft, missiles, satellites), such as autonomous obstacle avoidance for UAVs and orbital correction for spacecraft. Underwater inertial navigation for submarines and nuclear submarines (in environments without GPS signals). Automotive and Autonomous Driving: Assisting GPS positioning and maintaining vehicle position calculation in signal blind spots such as tunnels, high-rise buildings, and canyons. UAVs: Maintaining flight balance and executing complex flight paths such as hovering and circling. Robotics and Industry: Precise control of the end effector attitude of industrial robotic arms (such as welding and assembly). Service robots can sense their own movement trajectory to avoid falling or colliding.

[0003] To ensure navigation accuracy and reliability, key performance indicators such as zero-bias stability, scaling factor nonlinearity, and full-temperature zero-bias must be tested. The "JJF1535-2015 Microelectromechanical (MEMS) Gyroscope Calibration Specification" and the "JJF1427-2013 Microelectromechanical (MEMS) Linear Accelerometer Calibration Specification" specify calibration methods for various parameters of linear accelerometers and gyroscopes. Among these, scaling nonlinearity tests require a rate turntable. For sensors already fixed in the intelligent cockpit domain controller assembly, ensuring they remain stationary on the turntable and aligned with its center to guarantee test accuracy is a critical problem that needs to be solved.

[0004] Currently, existing technologies for fixing inertial measurement units (IMUs) on rate turntables mainly revolve around rigid mechanical positioning and modular fixture design. Rigid mechanical fixing directly and rigidly fixes the IMU to the turntable surface using bolts, clamps, or custom metal brackets, relying on machining precision to ensure positioning. The positioning pin-clamp type fixing structure uses a base and detachable clamps as core components, achieving IMU fixation through mechanical hard positioning. For example, a calibration fixture includes a base plate with positioning pins and two side plates. The IMU achieves initial positioning by engaging with 2-4 positioning pins on the base plate through openings in the bottom surface, and then clamping is completed through detachable connections (such as ring buckles and protruding hook structures) between the top fixing clamps and the side plates. This structure relies on the precise fit between the positioning pins and the openings in the IMU housing and is suitable for calibration fields of regularly shaped independent IMU sensors.

[0005] These calibration methods and devices inevitably have some drawbacks. For example, manual operation is easily affected by the operator's skill level, attention, and experience, leading to potential operational errors, and usually requires a significant investment of manpower and time. Operators need to repeatedly perform the instrument installation process, especially in large-scale or long-term monitoring networks, which may result in high labor and time costs. Furthermore, rigid fixing relying on machining makes it difficult to ensure that the geometric center of the inertial measurement unit (IMU) coincides perfectly with the rotation center of the turntable. Bolt tightening or interference fits introduce mechanical stress, causing zero-bias drift of the IMU sensor. Existing fixtures do not consider the impact of environmental factors such as temperature and vibration on IMU testing. For example, in full-temperature zero-bias testing, the thermal expansion coefficient of the metal bracket may not match that of the IMU housing, introducing additional stress errors. All of these can reduce the accuracy of calibration results. Existing solutions require customized fixtures for different IMU models, increasing the workload and reducing testing efficiency. Utility Model Content

[0006] The purpose of this invention is to address the shortcomings of the prior art by providing an adaptive inertial navigation assembly elastic clamp system. This system achieves stable adaptive preload control, effectively reduces drift caused by temperature changes, solves the problem of loosening of traditional fasteners under vibration, achieves high-precision alignment of the rate turntable center, overcomes the problem of requiring manual alignment of the center in traditional partial inertial measurement unit detection schemes, effectively reduces errors caused by center alignment, improves production efficiency, and reduces human error.

[0007] The objective of this utility model can be achieved by adopting the following technical solutions:

[0008] An adaptive inertial navigation assembly elastic clamping system includes a dual-layer adjustment platform module, an elastic clamping module, and a laser alignment module. The dual-layer adjustment platform module includes an upper platform and a lower platform. The bottom surface of the lower platform is provided with a connecting screw hole adapted to a rate turntable. The upper platform is slidably connected to the lower platform through a slide rail assembly. The elastic clamping module is mounted on the upper platform.

[0009] The elastic clamp module includes a shape memory alloy spring limiting device and a carbon fiber-ceramic composite material clamp body. The shape memory alloy spring limiting device is movably mounted on the upper platform, and the carbon fiber-ceramic composite material clamp body is fixedly mounted on the upper platform.

[0010] The laser alignment module includes a laser emitting module and a CMOS sensing component, which are mounted on the lower platform.

[0011] Furthermore, the shape memory alloy spring limiting device includes a two-way shape memory alloy spring and an elastic constraint structure. The two ends of the two-way shape memory alloy spring are fixedly connected to the carbon fiber-ceramic composite material clamp body and the elastic constraint structure, respectively. The carbon fiber-ceramic composite material clamp body and the elastic constraint structure have a clamping and positioning groove. The outer side of the elastic constraint structure is provided with a locking component, and an elastic gap is provided between the elastic constraint structure and the upper platform.

[0012] Furthermore, the elastic constraint structure is a metal bending component.

[0013] Furthermore, both the upper and lower platforms are made of lightweight alloy materials.

[0014] Furthermore, it also includes a temperature compensation module, which includes a first temperature compensation unit and a second temperature compensation unit. The first temperature compensation unit is disposed on the shape memory alloy spring limiting device, and the second temperature compensation unit is disposed on the carbon fiber-ceramic composite material fixture body.

[0015] Furthermore, the first temperature compensation unit includes a first temperature sensing element and a first heating element. The first temperature sensing element is attached to the double-pass shape memory alloy spring of the shape memory alloy spring limiting device, and the first heating element is wound around the double-pass shape memory alloy spring of the shape memory alloy spring limiting device.

[0016] Furthermore, the second temperature compensation unit includes a second temperature sensing element and a second heating component. The second temperature sensing element is embedded in the carbon fiber-ceramic composite material fixture body, and the second heating component is attached to the connecting surface of the carbon fiber-ceramic composite material fixture body.

[0017] Furthermore, the slide rail assembly includes a slide rail, a slider, and a screw. There are two slide rails. The slider is fixedly mounted on the bottom surface of the upper platform. The slider is slidably connected to the two slide rails respectively, and the center of the slider is threadedly connected to the screw. The screw and the two slide rails are mounted on the lower platform. One end of the screw is provided with an adjustment knob, and the other end of the screw is provided with a locking nut. The adjustment knob and the locking nut are located on both sides of the lower platform respectively.

[0018] Furthermore, the laser alignment module also includes an optical sight and an optical sight bracket, the CMOS sensing component is embedded in the optical sight, and the optical sight is mounted on the lower platform via the optical sight bracket.

[0019] Furthermore, the laser emitting module is a three-beam orthogonal laser emitting module, which includes three laser emitters, which are fixedly arranged on three different sides of the lower platform.

[0020] This utility model has the following advantages over the prior art:

[0021] This invention effectively solves the technical problems of low positioning accuracy, poor environmental adaptability, and insufficient operational flexibility in existing inertial navigation system (IMU) scaling nonlinearity testing through the collaborative design of a dual-layer adjustment platform module, an elastic clamp module, and a laser alignment module. The rigid connection between the lower platform and the rate turntable, along with the slide rail adjustment structure of the upper platform, combined with real-time detection by three orthogonal lasers and a CMOS sensor in the laser alignment module, achieves high-precision alignment between the geometric center of the IMU and the rotation axis of the turntable. This significantly reduces the scaling factor test error introduced by center offset, ensuring the accuracy of scaling nonlinearity test data. The intelligent elastic clamp module employs a combination of a two-way shape memory alloy spring and an elastic structure, with a 0.5mm elastic gap for buffering. This allows for flexible clamping of IMU assemblies of different sizes, avoiding damage to the IMU from rigid clamping. Furthermore, through the synergy of the carbon fiber-ceramic composite clamp body and the temperature compensation module, the clamp body deformation is controlled below 0.1μm within the full temperature range of -40℃ to 85℃, while simultaneously compensating for temperature-induced deformation of the shape memory alloy spring. The fluctuations in preload caused by changes effectively suppress the interference of temperature environment on test accuracy, ensuring test stability across the entire temperature range. Both the upper and lower platforms are made of lightweight aluminum alloy, which combines lightweight, high thermal conductivity, and vibration resistance, allowing for rapid dissipation of heat generated during testing and reducing the impact of temperature accumulation on the performance of the inertial navigation assembly. The nano-coating treatment on the surface of the carbon fiber-ceramic composite fixture body improves surface wear resistance and anti-slip properties, extending the service life of the fixture. In addition, the entire system has a standardized and flexible operation process. From fixing the lower platform and turntable, clamping the inertial navigation assembly, to laser alignment, locking and fixing, and disassembly after testing, each step has clear operating standards and accuracy guarantees. It can adapt to the testing needs of inertial navigation assemblies of different specifications, and the standardized process reduces the difficulty of operation and improves testing efficiency. It provides a high-precision, high-stability, and highly adaptable fixture solution for scaling nonlinear testing of inertial navigation assemblies, especially suitable for automotive-grade and industrial-grade inertial navigation assembly testing scenarios with stringent requirements for testing accuracy and environmental adaptability, greatly improving calibration efficiency. This achieves efficient utilization and improves the accuracy of metrological calibration. At the same time, it reduces the cost of metrological calibration. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0023] Figure 1This is a three-dimensional structural diagram of the adaptive inertial navigation assembly elastic clamp system from one angle, according to an embodiment of the present invention.

[0024] Figure 2 This is a three-dimensional structural view of the adaptive inertial navigation assembly elastic clamp system from another angle, according to an embodiment of this utility model.

[0025] Figure 3 This is a front view of the adaptive inertial navigation assembly elastic clamp system according to an embodiment of the present invention.

[0026] Figure 4 This is a three-dimensional structural diagram of the upper platform in the adaptive inertial navigation assembly elastic clamp system according to an embodiment of the present invention, taken from one angle.

[0027] Figure 5 This is a three-dimensional structural view of the upper platform in the adaptive inertial navigation assembly elastic clamp system according to another embodiment of the present invention.

[0028] Figure 6 This is a three-dimensional structural diagram of the lower platform in the adaptive inertial navigation assembly elastic clamp system according to an embodiment of the present invention.

[0029] Among them, 1-elastic clamp module, 11-shape memory alloy spring limiting device, 111-double-stroke shape memory alloy spring, 112-elastic constraint structure, 113-positioning component, 12-carbon fiber-ceramic composite material clamp body, 2-upper platform, 3-lower platform, 4-slide rail, 5-slider, 6-screw, 7-adjustment knob, 8-locking nut, 9-optical sight, 10-optical sight bracket. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this utility model, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the protection scope of this utility model.

[0031] Example:

[0032] like Figures 1-3As shown, this embodiment provides an adaptive inertial navigation assembly elastic clamp system. The system includes a dual-layer adjustment platform module, an elastic clamp module 1, and a laser alignment module. The dual-layer adjustment platform module serves as a clamp base and includes an upper platform 2 and a lower platform 3. The bottom surface of the lower platform 3 is provided with a connecting screw hole adapted to the rate turntable. The upper platform 2 is slidably connected to the lower platform 3 through a slide rail assembly.

[0033] like Figures 1-5 As shown, the elastic clamp module 1 is used to support and fix the inertial navigation assembly (IMU assembly), which is mounted on the upper platform 2. It includes a shape memory alloy (Ni-Ti system) spring limiting device 11 and a carbon fiber-ceramic composite material clamp body 12. The shape memory alloy spring limiting device 11 is movably mounted on the upper platform 2, and the carbon fiber-ceramic composite material clamp body 12 is fixedly mounted on the upper platform 2.

[0034] Furthermore, the shape memory alloy spring limiting device 11 includes a two-way shape memory alloy spring 111 and an elastic constraint structure 112. The two ends of the two-way shape memory alloy spring 111 are fixedly connected to the carbon fiber-ceramic composite material clamp body 12 and the elastic constraint structure 112, respectively. There is a clamping and positioning groove between the carbon fiber-ceramic composite material clamp body 12 and the elastic constraint structure 112. The clamping and positioning groove is used to place the inertial navigation assembly. A locking component 113 is provided on the outside of the elastic constraint structure 112. The locking component 113 is used to realize the flexible clamping and anti-loosening positioning of the inertial navigation assembly to prevent micro-rotation. An elastic gap is provided between the elastic constraint structure 112 and the upper platform 2.

[0035] Furthermore, both the carbon fiber-ceramic composite clamp body 12 and the elastic constraint structure 112 have baffles. The two ends of the two-way shape memory alloy spring 111 are specifically fixedly connected to the baffles of the carbon fiber-ceramic composite clamp body 12 and the elastic constraint structure 112. In order to stably clamp the inertial navigation assembly, two two-way shape memory alloy springs 111 can be provided. The elastic constraint structure 112 is a metal bending part. A 0.5mm elastic gap is reserved between the elastic constraint structure 112 and the inner wall of the upper platform 2. This gap provides buffer space for spring extension and structural deformation.

[0036] Furthermore, the carbon fiber-ceramic composite fixture body 12 is made of carbon fiber reinforced ceramic matrix composite material, and the ceramic matrix used is alumina. After process control, it has low thermal expansion characteristics. The thermal expansion coefficient of the carbon fiber-ceramic composite material is optimized to ensure that the deformation of the fixture body is less than 0.1μm when the temperature changes. The clamping inner surface of the carbon fiber-ceramic composite fixture body 12 is treated with a nano-coating to improve surface roughness and wear resistance. The mounting surface is provided with an M6×0.5 micro thread for threaded connection with the upper platform 2 to ensure that the coaxiality and flatness meet the accuracy requirements after assembly.

[0037] Furthermore, both the upper platform 2 and the lower platform 3 are made of lightweight alloy materials. In this embodiment, they are made of aluminum alloy, which has good thermal conductivity and vibration resistance.

[0038] like Figures 1-6 As shown, the slide rail assembly includes a slide rail 4, a slider 5, and a screw 6. There are two slide rails. The slider 5 is fixedly installed on the bottom surface of the upper platform 2. The slider 5 is slidably connected to the two slide rails 4 respectively, and the center of the slider 5 is threadedly connected to the screw 6. The screw 6 and the two slide rails 4 are installed on the lower platform. One end of the screw 6 is provided with an adjustment knob 7, and the other end of the screw 6 is provided with a locking nut 8. The adjustment knob 7 and the locking nut 8 are located on both sides of the lower platform 3 respectively.

[0039] The adaptive inertial navigation assembly elastic clamping system of this embodiment also includes a temperature compensation module. The temperature compensation module can use a temperature gradient compensation algorithm to maintain an alignment accuracy of less than 10 arcseconds in the range of -40℃ to 85℃. The temperature compensation module includes a first temperature compensation unit and a second temperature compensation unit. The first temperature compensation unit is set on the shape memory alloy spring limiting device, and the second temperature compensation unit is set on the carbon fiber-ceramic composite material clamping body.

[0040] Furthermore, the first temperature compensation unit is used to compensate for the change in preload of the two-way shape memory alloy spring 111. It includes a first temperature sensing element and a first heating element. The first temperature sensing element is attached to the two-way shape memory alloy spring 111, and the first heating element is wound around the two-way shape memory alloy spring 111.

[0041] Furthermore, the second temperature compensation unit is used to compensate for the dimensional changes caused by temperature changes in the carbon fiber-ceramic composite fixture body 12. It includes a second temperature sensing element and a second heating component. The second temperature sensing element is embedded in the carbon fiber-ceramic composite fixture body 12, and the second heating component is attached to the connecting surface of the carbon fiber-ceramic composite fixture body 12.

[0042] The laser alignment module in this embodiment includes a laser emitting module and a CMOS (Complementary Metal Oxide Semiconductor) sensing component. The laser emitting module and the CMOS sensing component are mounted on the lower platform 3. The laser emitting module is a three-beam orthogonal laser emitting module, which includes three laser emitters. The three laser emitters are fixedly arranged on three different sides of the lower platform 3, corresponding to the X / Y / Z axes, with the X-axis being the main adjustment direction. It includes a laser element, a collimating lens, and a heat dissipation housing. The laser beams illuminate the inertial navigation assembly along the coordinate axes. The wavelength of the three laser beams is 650nm, and the power is 5mW. The CMOS sensing component includes a high-pixel chip and an adapter lens, which are used to capture the light spot and detect alignment deviations.

[0043] Furthermore, the laser alignment module also includes an optical sight 9 and an optical sight bracket 10. The optical sight 9 is mounted on the lower platform 3 via the optical sight bracket 10. The optical sight 9 is used for initial alignment of the inertial navigation assembly. The lens of the optical sight 9 is made of high-precision optical glass, which has good optical performance and wear resistance. The X-axis laser emitter and CMOS sensing components can be set on the optical sight bracket 10 facing the inertial navigation assembly.

[0044] The adaptive inertial navigation assembly elastic clamp system of this embodiment also includes auxiliary connectors, including an L-shaped metal bracket for fixing the laser emission module, a transparent dust cover for protecting the CMOS sensing components, and a waterproof aviation plug for connecting the temperature compensation module and the external controller; the dust cover is connected by buckles, and the cover wall is provided with ventilation holes to prevent fogging; the aviation plug has sealing components to ensure that the protection level is adapted to the test environment.

[0045] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and agreed, the terms "set," "install," and "connect" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances. The terms "upper," "lower," "left," "right," and similar expressions used are for illustrative purposes only and do not represent the only possible implementation.

[0046] In summary, the elastic clamp module of this invention incorporates a shape memory alloy spring limiting device and a carbon fiber-ceramic composite clamp body. By employing these components, stable adaptive preload control is achieved within a temperature range of -40℃ to 85℃, effectively reducing drift caused by temperature changes and solving the problem of loosening of traditional fasteners under vibration. Furthermore, this invention utilizes a laser alignment module to achieve high-precision alignment of the rate turntable center, overcoming the need for manual center alignment in traditional partial inertial measurement unit detection schemes, effectively reducing errors caused by center alignment, improving production efficiency, and reducing human error.

[0047] The above description is only a preferred embodiment of this utility model patent, but the protection scope of this utility model patent is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the scope disclosed in this utility model patent, based on the technical solution and utility model concept of this utility model patent, shall fall within the protection scope of this utility model patent.

Claims

1. An adaptive inertial navigation assembly elastic clamp system, characterized in that, It includes a dual-layer adjustment platform module, an elastic clamp module, and a laser alignment module. The dual-layer adjustment platform module includes an upper platform and a lower platform. The bottom surface of the lower platform is provided with a connecting screw hole adapted to the rate turntable. The upper platform is slidably connected to the lower platform through a slide rail assembly. The elastic clamp module is mounted on the upper platform. The elastic clamp module includes a shape memory alloy spring limiting device and a carbon fiber-ceramic composite material clamp body. The shape memory alloy spring limiting device is movably mounted on the upper platform, and the carbon fiber-ceramic composite material clamp body is fixedly mounted on the upper platform. The laser alignment module includes a laser emitting module and a CMOS sensing component, which are mounted on the lower platform.

2. The adaptive inertial navigation assembly elastic clamp system according to claim 1, characterized in that, The shape memory alloy spring limiting device includes a two-way shape memory alloy spring and an elastic constraint structure. The two ends of the two-way shape memory alloy spring are fixedly connected to the carbon fiber-ceramic composite material clamp body and the elastic constraint structure, respectively. The carbon fiber-ceramic composite material clamp body and the elastic constraint structure have a clamping and positioning groove. The outer side of the elastic constraint structure is provided with a locking component, and an elastic gap is provided between the elastic constraint structure and the upper platform.

3. The adaptive inertial navigation assembly elastic clamp system according to claim 2, characterized in that, The elastic constraint structure is a metal bending component.

4. The adaptive inertial navigation assembly elastic clamp system according to claim 1, characterized in that, Both the upper and lower platforms are made of lightweight alloy materials.

5. The adaptive inertial navigation assembly elastic clamp system according to claim 1, characterized in that, It also includes a temperature compensation module, which includes a first temperature compensation unit and a second temperature compensation unit. The first temperature compensation unit is disposed on the shape memory alloy spring limiting device, and the second temperature compensation unit is disposed on the carbon fiber-ceramic composite material fixture body.

6. The adaptive inertial navigation assembly elastic clamp system according to claim 5, characterized in that, The first temperature compensation unit includes a first temperature sensing element and a first heating element. The first temperature sensing element is attached to the double-pass shape memory alloy spring of the shape memory alloy spring limiting device, and the first heating element is wound around the double-pass shape memory alloy spring of the shape memory alloy spring limiting device.

7. The adaptive inertial navigation assembly elastic clamp system according to claim 5, characterized in that, The second temperature compensation unit includes a second temperature sensing element and a second heating component. The second temperature sensing element is embedded in the carbon fiber-ceramic composite material fixture body, and the second heating component is attached to the connecting surface of the carbon fiber-ceramic composite material fixture body.

8. The adaptive inertial navigation assembly elastic clamp system according to any one of claims 1-7, characterized in that, The slide rail assembly includes slide rails, sliders, and screws. There are two slide rails. The sliders are fixedly mounted on the bottom surface of the upper platform and are slidably connected to the two slide rails respectively. The center of the sliders is threadedly connected to the screws. The screws and the two slide rails are mounted on the lower platform. One end of the screw is equipped with an adjustment knob, and the other end of the screw is equipped with a locking nut. The adjustment knob and the locking nut are located on both sides of the lower platform respectively.

9. The adaptive inertial navigation assembly elastic clamp system according to any one of claims 1-7, characterized in that, The laser alignment module also includes an optical sight and an optical sight bracket. The CMOS sensing component is embedded in the optical sight, and the optical sight is mounted on the lower platform via the optical sight bracket.

10. The adaptive inertial navigation assembly elastic clamp system according to any one of claims 1-7, characterized in that, The laser emitting module is a three-beam orthogonal laser emitting module, which includes three laser emitters, which are fixedly installed on three different sides of the lower platform.

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