Navigation grade MEMS IMU VS Tactical grade MEME IMU

 Introduce

Navigation-grade IMU and tactical-grade IMU are different levels of inertial measurement units (IMU). They have significant differences in accuracy, performance and application scenarios. Navigation-level and tactical-level IMU will be introduced below.

Navigation grade MEMS IMU

First of all, navigation-grade IMU is mainly used for general navigation and positioning tasks, and its performance requirements are relatively low. It usually has high accuracy and reliability and can meet the needs of most navigation applications. Through internal sensors such as accelerometers and gyroscopes, the navigation-grade IMU can accurately measure key information such as the acceleration, angular velocity, and direction of objects. After processing, this information can be used to achieve precise positioning and navigation functions, thereby improving driving safety and stability.

Tactical Grade MEMS IMU

Tactical-grade IMU have some unique core features. For example, they are able to operate gyroscopes with extremely low bias stability, meaning that bias errors become more stable over time. This stability is critical for high-precision applications such as drone navigation. And for higher-precision applications, such as drone navigation, antenna and weapon platform stabilization, tactical-grade IMU are required. Gyroscopes are known to operate with extremely low bias stability, meaning their bias errors remain relatively stable over time. This feature allows tactical-grade IMU to maintain excellent performance in long-term, high-precision applications. In addition, tactical-grade IMU are usually equipped with high-quality MEMS accelerometers and gyroscopes to provide more accurate data output.

It can be seen that navigation-grade IMU and tactical-grade IMU have different emphasis on accuracy, performance and application scenarios. When selecting an IMU, the most appropriate level needs to be determined based on specific application requirements. The following will briefly describe the differences between navigation-grade MEMS IMU and tactical-grade MEMS IMU, and introduce two IMU from the domestic inertial navigation company ERICCO.

Navigation grade MEMS IMU VS Tactical grade MEMS IMU

There are significant differences in performance and application between navigation-grade IMU and tactical-grade IMU.

First of all, navigation-grade IMU are usually used in scenarios that require relatively low accuracy, and their performance and accuracy may not be as good as tactical-grade IMU. Secondly, tactical-grade IMU offer higher performance and accuracy, making them the first choice for demanding applications such as drone navigation. These IMUs operate gyroscopes with extremely low bias stability, which means the bias error becomes more stable over time. This characteristic is essential for mission-critical and high-precision applications such as drone navigation, antenna and weapon platform stabilization.

ERICCO is an inertial navigation company that independently develops MEMS IMU. The MERMS IMU it develops are mainly divided into navigation level and tactical level. The following are the company’s ER-MIMU-01 (navigation level) and ER-MIMU-03 (tactical level). Level) built-in MEMS gyroscope specification comparison : 

It can be seen from the above table that the accuracy of the built-in gyroscope of the navigation-grade MEMS IMU is much higher than that of the tactical-grade one, especially the bias instability of the navigation-grade one is 0.02, and the tactical-grade one is 0.3. The accuracy is much higher. ER-MIMU-03 has a larger range than ER-MIMU-01.

Summarize

Navigation-grade IMU and tactical-grade IMU are different in accuracy, stability and applicable scenarios. When selecting, the most appropriate IMU type needs to be determined based on specific application requirements. For more professional information, please consult our relevant personnel.

Email: info@ericcointernational.com
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website:https://www.ericcointernational.com/inertial-measurement-units

Fiber Optic Gyroscopes for Inertial Navigation

 

1. What is inertial navigation

To understand what inertial navigation is, we first need to break the phrase into two parts, that is, navigation + inertia.
Navigation, in simple terms, solves the problem of getting from one place to another, indicating the direction, typically the compass.
Inertia, originally derived from Newtonian mechanics, refers to the property of an object that maintains its state of motion. It has the function of recording the motion state information of the object.
A simple example is used to illustrate inertial navigation. A child and a friend play a game at the entrance of a room covered with tiles, and walk on the tiles to the other side according to certain rules. One forward, three left, five front, two right... Each of his steps is the length of a floor tile, and people outside the room can get his complete motion trajectory by drawing the corresponding length and route on the paper. He doesn't need to see the room to know the child's position, speed, etc.
The basic principle of inertial navigation and some other types of navigation is pretty much like this: know your initial position, initial orientation (attitude), the direction and direction of movement at each moment, and push forward a little bit. Add these together (corresponding to the mathematical integration operation), and you can just get your orientation, position and other information.
So how to get the current orientation (attitude) and position information of the moving object? You need to use a lot of sensors, in inertial navigation is the use of inertial instruments: accelerometer + gyroscope.
Inertial navigation uses gyroscope and accelerometer to measure the angular velocity and acceleration of the carrier in the inertial reference frame, and integrates and calculates the time to obtain the velocity and relative position, and transforms it into the navigation coordinate system, so that the carrier's current position can be obtained by combining the initial position information.
Inertial navigation is an internal closed loop navigation system, and there is no external data input to correct the error during the carrier movement. Therefore, a single inertial navigation system can only be used for short periods of navigation. For the system running for a long time, it is necessary to periodically correct the internal accumulated error by means of satellite navigation.

2. Gyroscopes in inertial navigation

Inertial navigation technology is widely used in aerospace, navigation satellite, UAV and other fields because of its high concealment and complete autonomous ability to obtain motion information. Especially in the fields of micro-drones and autonomous driving, inertial navigation technology can provide accurate direction and speed information, and can play an irreplaceable role in complex conditions or when other external auxiliary navigation signals fail to play the advantages of autonomous navigation in the environment to achieve reliable attitude and position measurement. As an important component in inertial navigation system, fiber optic gyro plays a decisive role in its navigation ability. At present, there are mainly fiber optic gyroscopes and MEMS gyroscopes on the market. Although the precision of the fiber optic gyroscope is high, its entire system is composed of couplers,
Modulator, optical fiber ring and other discrete components, resulting in large volume, high cost, in the micro UAV, unmanned and other fields can not meet the requirements for its miniaturization and low cost, the application is greatly limited. Although MEMS gyro can achieve miniaturization, its accuracy is low. In addition, it has moving parts, poor resistance to shock and vibration, and is difficult to apply in harsh environments.

 

3 Summary

Ericco's fiber optic gyroscope ER-FOG-851 is specially designed according to the concept of traditional fiber optic gyroscopes, with a small size of 78.5*78.5*35mm; Light weight, less than or equal to 300g; Low power consumption, less than or equal to 4W; Start fast, start time is only 5s; This fiber optic gyroscope easy to operate and easy to use, and is widely used in INS, IMU, positioning system, north finding system, platform stability and other fields.
The accuracy of our ER-FOG-851 is between 0.05 and 0.1, and the 851 is divided into ER-FOG-851D and ER-FOG-851H. The biggest difference between these two fiber optic gyroscope is that the measurement range is different, of course, the accuracy is different, and the measurement range of ER-FOG-851D is wider. The application range is naturally wider than the ER-FOG-851H. Our fiber optic gyroscope can be used in inertial navigation, you can make a detailed choice according to the accuracy value and measurement range, you are welcome to consult us at any time and get more technical data.

 

Features of Fiber Optic Gyroscope

 

1.Characteristics of fiber optic gyro

Compared with electromechanical gyro or laser gyro, fiber optic gyro has the following characteristics:

(1) fewer parts, the instrument is firm and stable, and has a strong ability to resist impact and accelerate movement;
(2) The wound fiber is longer, so that the detection sensitivity and resolution are several orders of magnitude higher than that of the laser gyroscope;
(3) No mechanical transmission parts, no wear problems, so it has a long service life;
(4) Easy to use integrated optical path technology, signal stability, and can be directly digital output, and connected with the computer interface;
(5) By changing the length of the fiber or the number of times the light circulates in the coil, different accuracy can be achieved and a wide dynamic range can be achieved;
(6) The propagation time of the coherent beam is short, so in principle it can be started instantaneously without preheating;
(7) can be used with ring laser gyro to form sensors of various inertial navigation systems, especially sensors of strapdown inertial navigation systems;
(8) Simple structure, low price, small size, light weight.

2.Principle of fiber optic gyroscope

Fiber optic gyro is a fiber optic angular velocity sensor, which is the most promising one among all kinds of fiber optic sensors. Like ring laser gyro, fiber optic gyro has the advantages of no mechanical moving parts, no preheating time, insensitive acceleration, wide dynamic range, digital output and small size. In addition, fiber optic gyro also overcomes the fatal shortcomings of ring laser gyro such as high cost and blocking phenomenon. Therefore, fiber optic gyro has been paid attention to by many countries. Low precision civilian fiber optic gyro has been produced in small batch in Western Europe, it is estimated that in 1994, the sales of fiber optic gyro in the United States gyro market reached 49%, and the cable gyro fell to the second place (accounting for 35% of sales).

The working principle of fiber optic gyroscopes is based on the Sagnac effect. Sagnac effect is a general correlation effect of light propagated in a closed loop optical path rotating relative to inertial space, that is, two beams of light with equal characteristics emitted from the same light source in the same closed optical path propagate in opposite directions, and finally converge to the same detection point.

3.Application of fiber optic gyro

What if a car with a satellite navigation system is driving and suddenly can't receive GPS navigation signals? With the addition of a fiber optic gyroscope, it can form integrated navigation with GDS to achieve automatic driving.

Fiber optic gyro technology is based on mechanical gyro, MEMS gyro, laser gyro upgrade and development, with self-correcting, high sensitivity, long life, low temperature and high temperature resistance, no electromagnetic interference and many other advantages, is the best comprehensive performance of inertial sensors. Due to high cost, it is mainly used in military industry, aerospace and other fields.

Fiber optic gyro technology can be widely used in automotive navigation, high-speed rail track detection, Internet of Things components module, smart grid transmission, consumer electronics and many other fields, experts predict that the potential market size of domestic fiber optic gyro reached 100 billion, the next 5-10 years, most of China's traditional gyro market will be replaced by fiber optic gyro.

4.Summary

Ericco's fiber optic gyro is also a leading level in the world, ER-FOG-851 (≤0.05 ~ 0.1º/h), ER-FOG-910(0.02º/h) are a good choice, because they are medium precision, widely used, if you want to get more technical parameters, please feel free to contact us.

IMU Data Denoising Method Based on Wavelet Decomposition

 

https://www.ericcointernational.com/application/imu-data-denoising-method-based-on-wavelet-decomposition.html

In the noise reduction process of IMU (Inertial Measurement Unit), wavelet denoising is an effective method. The basic principle of wavelet denoising is to use the multi-resolution time-frequency localization characteristics of wavelets to decompose the components of different frequencies in the signal into different subspaces, and then process the wavelet coefficients in these subspaces to remove noise.

 

Specifically, the process of wavelet denoising can be divided into the following three steps:

1.Perform wavelet transformation on the noisy IMU signal and decompose it into different wavelet subspaces.

2.Threshold the coefficients in these wavelet subspaces, that is, coefficients below a certain threshold are regarded as noise and set to zero, while coefficients above the threshold are retained, and these coefficients usually contain useful signal information.

3.Perform inverse transformation on the processed wavelet coefficients to obtain the denoised signal.

 

This method can effectively remove the noise in the IMU signal and improve the quality and accuracy of the signal. At the same time, because the wavelet transform has good time-frequency characteristics, it can better retain the useful information in the signal and avoid excessive information loss during the denoising process.

 

Please note that the specific threshold selection and processing methods may vary according to specific signal characteristics and noise conditions, and therefore need to be adjusted and optimized according to specific circumstances in actual applications.

 

The IMU data denoising method based on wavelet decomposition is an effective signal processing technology used to remove noise from IMU (Inertial Measurement Unit) data. IMU data often contains high-frequency noise and low-frequency drift, which can affect the accuracy and performance of the IMU. The noise reduction method based on wavelet decomposition can effectively separate and remove these noises and drifts, thereby improving the accuracy and reliability of IMU data.

 

Wavelet decomposition is a multi-scale analysis technique that can decompose signals into wavelet components of different frequencies and scales. By wavelet decomposing the IMU data, high-frequency noise and low-frequency drift can be separated and processed differently.

 

The IMU data denoising method based on wavelet decomposition usually includes the following steps:

1.Perform wavelet decomposition on the IMU data and decompose it into wavelet components of different frequencies and scales.

2.According to the characteristics of the wavelet components, select an appropriate threshold or wavelet coefficient processing method to suppress or remove high-frequency noise.

3.Model and compensate for low-frequency drift to reduce its impact on IMU data.

4.Reconstruct the processed wavelet components to obtain denoised IMU data.

 

The IMU data denoising method based on wavelet decomposition has the following advantages:

1.Able to effectively separate and remove high-frequency noise and low-frequency drift, improving the accuracy and reliability of IMU data.

2.Have good time-frequency analysis capabilities and be able to process the time and frequency information of signals at the same time.

3.Suitable for different types of IMU data and different application scenarios, with strong versatility and flexibility.

 

Summarize

In short, the IMU data denoising method based on wavelet decomposition is an effective signal processing technology that can improve the accuracy and reliability of IMU data and provide more accurate and reliable data for inertial navigation, attitude estimation, motion tracking and other fields. support.

The IMU independently developed by Ericco Company uses some relatively rigorous denoising methods to better demonstrate to consumers higher-precision and low-cost MEMS IMUs, such as ER-MIMU-01 and ER-MIMU-02 as navigation series MEMS IMUs. Technicians conducted various experiments to denoise the IMU data to better meet consumers' accurate measurement of the motion state of objects.

If you want to know more about IMU, please contact our relevant personnel.

Research on Hybrid Integrated Optical Chip of Fiber Optic Gyro

 With the advantages of all-solid state, high performance and flexible design, fiber optic gyroscope has become the mainstream inertial gyroscope, which is widely used in many fields such as positioning and navigation, attitude control and oil well inclination measurement. Under the new situation, the new generation of inertial navigation system is developing towards miniaturization and low cost, which puts forward higher and higher requirements for the comprehensive performance of gyroscope such as volume, accuracy and cost. In recent years, hemispherical resonator gyro and MEMS gyro have developed rapidly with the advantage of small size, which has a certain impact on the fiber optic gyro market. The main challenge of traditional optical gyro volume reduction is the reduction of optical path volume. In the traditional scheme, the optical route of fiber optic gyro is composed of several discrete optical devices, each of which is realized based on different principles and processes and has independent packaging and pigtail. As a result, the device volume under the prior art is close to the reduction limit, and it is difficult to support the further reduction of the volume of fiber optic gyro. Therefore, it is urgent to explore new technical solutions to realize the effective integration of different functions of the optical path, greatly reduce the volume of the gyro optical path, improve the process compatibility, and reduce the production cost of the device.

With the development of semiconductor integrated circuit technology, integrated optical technology has gradually achieved breakthroughs, and the feature size has been continuously reduced, and it has entered the micro and nano level, which has greatly promoted the technical development of integrated optical chips, and has been applied in optical communication, optical computing, optical sensing and other fields. The integrated optical technology provides a new and promising technical solution for the miniaturization and low cost of fiber optic gyro optical path.

1 Integrated optical chip scheme design

1.1 Overall Design

The traditional optical routing light source (SLD or ASE), fiber taper coupler (referred to as "coupler"), Y branch waveguide phase modulator (referred to as "Y waveguide modulator"), detector, sensitive ring (fiber ring). Among them, the sensitive ring is the core unit of the sensitive Angle rate, and its volume size directly affects the precision of the gyro.
We propose a hybrid integrated chip, which consists of a light source component, a multifunctional component and a detection component through hybrid integration. Among them, the light source part is an independent component, which is composed of SLD chip, isolation collimation component and peripheral components such as heat sink and semiconductor cooler. The detection module consists of a detection chip and a transresistance amplifier chip. The multifunctional module is the main body of hybrid integrated chip, which is realized based on lithium niobate thin film (LNOI) chip, and mainly includes optical waveguide, mode-spot conversion, polarizer, beam splitter, mode attenuator, modulator and other on-chip structures. The beam emitted by the SLD chip is transmitted into the LNOI waveguide after isolation and collimation.
The polarizer deflects the input light, and the mode attenuator attenuates the non-working mode. After the beam splitter splits the beam and modulator modulates the phase, the output chip enters the sensitive ring and the sensitive angular rate. The light intensity is captured by the detector chip, and the generated photoelectric output flows through the transresistance amplifier chip to the demodulation circuit.
The hybrid integrated optical chip has the functions of luminescence, beam splitting, beam combining, deflection, modulation, detection, etc. It realizes the "multi-in-one" integration of non-sensitive functions of gyro optical path. Fiber optic gyroscopes depend on the sensitive Angle rate of coherent beam with high degree of polarization, and the polarization performance directly affects the precision of gyroscopes. The traditional Y-waveguide modulator itself is an integrated device, which has the functions of deflection, beam splitting, beam combining and modulation. Thanks to material modification methods such as proton exchange or titanium diffusion, Y-waveguide modulators have extremely high deflection ability. However, thin film materials need to take into account the requirements of size, integration and deflection ability, which can not be met by material modification methods. On the other hand, the mode field of thin film optical waveguide is much smaller than that of bulk material optical waveguide, resulting in changes in electrostatic field distribution and electrorefractive index parameters, and the electrode structure needs to be redesigned. Therefore, the polarizer and modulator are the core design points of the "all-in-one" chip.

1.2 Specific Design

The polarization characteristics are obtained by structural bias, and an on-chip polarizer is designed, which consists of curved waveguide and straight waveguide
Agreed. The curved waveguide can limit the difference between the transmission mode and the non-transmission mode, and achieve the effect of mode bias. The transmission loss of the transmission mode is reduced by setting the offset.
The transmission characteristics of optical waveguide are mainly affected by scattering loss, mode leakage, radiation loss and mode mismatch loss. Theoretically, the scattering loss and mode leakage of small curved waveguides are small, which are mainly limited by the late process. However, the radiation loss of curved waveguides is inherent and has different effects on different modes. The transmission characteristics of the curved waveguide are mainly affected by the mode mismatch loss, and there is mode overlap at the junction of the straight waveguide and the curved waveguide, resulting in a sharp increase in mode scattering. When the light wave is transmitted into the polarized waveguide, due to the existence of curvature, the effective refractive index of the light wave mode is different in the vertical direction and the parallel direction, and the mode restriction is different, which results in different attenuation effects for TE and TM modes.
Therefore, it is necessary to design the bending waveguide parameters to achieve the deflection performance. Among them, bending radius is the key parameter of bending waveguide. The transmission loss under different bending radius and the loss comparison between different modes are calculated by FDTD eigenmode solver. The calculated results show that the loss of the waveguide decreases with the increase of the radius at small bending radius. On this basis, the relationship between polarization property (ratio of TE mode to TM mode) and bending radius is calculated, and the polarization property is inversely proportional to bending radius. The determination of the bending radius of the on-chip polarizer should consider the theoretical calculation, the simulation results, the technological capability and the actual demand.
The finite difference Time domain (FDTD) is used to simulate the transmitted light field of the on-chip polarizer. The TE mode can pass through the waveguide structure with low loss, while the TM mode can produce obvious mode attenuation, so as to obtain polarized light with high extinction ratio. By increasing the number of cascaded waveguides, the extinction ratio of the polarization-extinction ratio can be further improved, and better than -35dB polarization extinction ratio performance can be obtained on the micron scale. At the same time, the structure of the waveguide on chip is simple, and it is easy to realize the low-cost fabrication of the device.

2 Integrated optical chip performance verification

The LNOI main chip of the integrated optical chip is an unsliced sample engraved with multiple chip structures, and the size of a single LNOI main chip is 11mm×3mm. The performance test of integrated optical chip mainly includes the measurement of spectral ratio, polarization extinction ratio and half-wave voltage.
Based on the integrated optical chip, a gyroscope prototype is built, and the performance test of the integrated optical chip is carried out. Static zero bias performance of a gyro prototype based on integrated optical chip in a non-vibration isolated foundation at room temperature. set-based
The gyroscope formed into optical chip has a long time drift in the start-up segment, which is mainly caused by the start-up characteristic of light source and the large loss of optical link. In the 90min test, the zero bias stability of the gyroscope is 0.17°/h (10s). Compared with the gyroscope based on traditional discrete devices, the zero bias stability index deteriorates by an order of magnitude, indicating that the integrated optical chip needs to be further optimized. Main optimization directions: improve the polarization extinction ratio of the chip, improve the luminous power of the light-emitting chip, improve the end-coupling efficiency of the chip, and reduce the overall loss of the integrated chip.

3 Summary

We propose an integrated optical chip based on LNOI, which can realize the integration of non-sensitive functions such as luminescence, beam splitting, beam combining, deflection, modulation and detection. The zero bias stability of the gyro prototype based on the integrated optical chip is 0.17°/h. Compared with the traditional discrete devices, the performance of the chip still has a certain gap, which needs to be further optimized and improved. We preliminarily explore the feasibility of fully integrated optical path functions except ring, which can maximize the application value of integrated optical chip in gyro, and meet the development needs of miniaturization and low cost of fiber optic gyro.

Ericco's ER-FOG-851, ER-FOG-910 small size, low power consumption, of course, the cost is also low, the application field is particularly wide, such as IMU, INS, north finding system, etc., I believe you must want to know their specific technical parameters, please feel free to contact us.

Pipeline IMU Detection Principle and Data Processing

 https://www.ericcointernational.com/application/pipeline-imu-detection-principle-and-data-processing.html

1.IMU measurement principle

IMU (Inertial Measurement Unit) is a device that can measure the angular velocity and acceleration of an object in three-dimensional space. Its core components usually include a three-axis gyroscope and a three-axis accelerometer. Gyroscopes are used to measure the angular velocity of an object about three orthogonal axes, while accelerometers are used to measure the acceleration of an object along three orthogonal axes. By integrating these measurements, the velocity, displacement and attitude information of the object can be obtained.

 

2.Pipe bending strain identification

In pipeline inspection, IMU can be used to identify the bending strain of the pipeline. When an IMU is installed on a pig or other mobile device and moves within a pipeline, it can sense changes in acceleration and angular velocity caused by pipeline bending. By analyzing this data, the degree and location of pipe bends can be identified.

 

3.Diameter measurement and pipe cleaning process

The diameter measuring and cleaning process is an important part of pipeline maintenance. In this process, a caliper pig equipped with an IMU is used to move along the pipeline, measure the inner diameter of the pipeline, and record the shape and size of the pipeline. This data can be used to assess the health of pipelines and predict possible maintenance needs.

 

4.Steel brush cleaning process

The steel brush pigging process is used to remove dirt and sediment from the inner walls of pipelines. In this process, a pig with a steel brush and an IMU moves along the pipeline, cleaning the inner wall of the pipeline through brushing and scouring. The IMU can record the geometric information and cleanliness of the pipeline during this process.

 

5.IMU detection process

The IMU inspection process is a key step in using IMU for data collection and measurement during pipeline maintenance. The IMU is installed on a pig or similar equipment and moves inside the pipeline while recording acceleration, angular velocity and other parameters. This data can be used to analyze the health of the pipeline, identify potential problems, and provide a basis for subsequent maintenance and management.

 

6.Data acquisition and post-processing

After completing the IMU detection process, the collected data need to be collected and post-processed. Data acquisition involves transferring raw data from the IMU device to a computer or other data processing device. Post-processing involves cleaning, calibrating, analyzing and visualizing the data. Through post-processing, useful information can be extracted from the original data, such as the shape, size, bending degree, etc. of the pipe.

 

7.Speed and attitude measurement

IMU can calculate the speed and attitude of an object by measuring acceleration and angular velocity. In pipeline inspection, measurement of speed and attitude is critical to assess the health of the pipeline and identify potential problems. By monitoring the speed and attitude changes of the pig in the pipeline, the shape, bending degree and possible obstacles of the pipeline can be inferred.

 

8.Pipe Curvature and Strain Assessment

Using the data measured by the IMU, the curvature and strain of the pipeline can be evaluated. By analyzing acceleration and angular velocity data, the radius of curvature and bending angle of the pipe at different locations can be calculated. At the same time, combined with the material properties and loading conditions of the pipe, the strain level and stress distribution of the pipe at the bend can also be evaluated. This information is important for predicting the life of pipelines, assessing safety, and developing maintenance plans.

 

Summarize

To sum up, IMU plays an important role in pipeline inspection. By measuring parameters such as acceleration and angular velocity, comprehensive assessment and maintenance of pipeline health can be achieved. With the continuous advancement of technology and the expansion of application fields, the application of IMU in pipeline inspection will become more and more extensive. The MEMS IMU independently developed by ERICCO has relatively high accuracy, such as ER-MIMU-01 and ER-MIMU-05, which are more accurate and are navigation-grade products. If you want to know more about IMU, please contact our professional technicians as soon as possible.

Application of Fiber Optic Gyroscope

 There are many ways to classify fiber optic gyroscopes. According to the working principle, it can be divided into three types: interference type, resonant type and stimulated Brillouin scattering fiber gyro. Among them, the interferometric fiber optic gyroscope is the first generation of fiber optic gyroscope, which uses multi-turn fiber coil to enhance the Sagnac effect. It is currently the most widely used; it can be divided into open-loop fiber gyroscope and closed loop according to different electric signal processing methods. Fiber optic gyroscopes, in general, closed-loop fiber optic gyroscopes have higher precision due to closed-loop control; they can be divided into single-axis fiber gyroscopes and multi-axis gyroscopes according to structure, among which three-axis fiber gyroscopes have volume Small, measurable spatial position and other advantages are an important development direction of fiber optic gyroscopes.

1.What is a fiber optic gyroscope? What are its applications in life?

A fiber optic gyroscope (FOG) is an angular velocity sensor based on the Sagnac effect, which detects angular velocity by measuring the phase difference of light traveling through an optical fiber. Compared with the traditional mechanical gyroscope, fiber optic gyroscope has the advantages of small size, light weight, high precision and good reliability, so it has been widely used in many fields.
In life, fiber optic gyro is mainly used in the field of navigation, such as car navigation, ship navigation, aircraft navigation and so on. Fiber optic gyroscopes can provide high-precision angular velocity measurements to help navigation systems more accurately determine the position and direction of a vehicle, boat or aircraft. In addition, fiber optic gyro can also be used in industrial control fields, such as robot attitude control, motion control of industrial machine tools, etc. In these applications, fiber optic gyroscopes can help achieve high-precision motion control and improve production efficiency and quality.
In addition, fiber optic gyro has also been widely used in the military field, such as missile guidance, spacecraft attitude control and so on. In these applications, the high accuracy and reliability of fiber optic gyroscopes are crucial. In general, the fiber optic gyro is a very important sensor, its application field is constantly expanding, for our life and work to bring a lot of convenience.

2.How does a fiber optic gyroscope work?

The working principle of a fiber optic gyroscope is based on the Sagnac effect. In simple terms, the Sagnac effect means that when light travels in a closed optical path, the phase of the light changes if there is an angular velocity of rotation.
In a fiber optic gyroscope, light from a light source passes through a coil of fiber and forms two beams of light in the fiber, which travel in opposite directions. When a fiber optic gyroscope spins, the phase of the two beams of light differs due to the Sagnac effect. By detecting this phase difference, the rotation angular speed of the fiber optic gyroscope can be calculated.
In order to detect phase differences, interferometers are usually used in fiber optic gyroscopes. The interferometer can convert the phase difference of two beams of light into the change of light intensity, so as to measure the rotational angular velocity. In practical applications, the fiber optic gyroscope also needs to carry out temperature compensation, polarization control and other measures to improve the measurement accuracy and stability.
The working principle of fiber optic gyroscope is relatively complicated, but its high precision and high reliability make it widely used in many fields. In the future, with the continuous development of technology, the performance of fiber optic gyro will continue to improve, bringing convenience to more fields.

3.What factors will affect the use of fiber optic gyroscopes? How to improve its measurement accuracy?

The measurement accuracy of fiber optic gyroscope will be affected by many factors during its use. Here are some common contributing factors:
Temperature: Changes in temperature can cause changes in the length and refractive index of the fiber, which affects the speed and phase of light propagation. Therefore, the fiber optic gyroscope needs temperature compensation to reduce the influence of temperature on the measurement accuracy.
Vibration: Vibration will change the optical path of the fiber optic gyroscope, which will affect the measurement of the phase difference. In order to reduce the impact of vibration, vibration reduction measures can be adopted, such as using shock absorbers, increasing the stiffness of the structure, etc.
Magnetic field: The magnetic field will change the polarization state of the light in the fiber, which will affect the output of the interferometer. In order to reduce the influence of magnetic fields, magnetic shielding technology can be used or diamagnetic fiber can be used.
Light source stability: the power fluctuation and wavelength drift of the light source will affect the measurement accuracy of the fiber optic gyroscope. Therefore, it is necessary to select a stable light source and control the temperature and power of the light source.
Fiber loss: The loss of the fiber will lead to the attenuation of the optical signal, which will affect the measurement accuracy. In order to reduce the impact of fiber loss, it is necessary to select low-loss fiber, and optimize the fiber connection and packaging.
In order to improve the measurement accuracy of the fiber optic gyroscope, the following measures can be taken:
Optimizing the design of the fiber optic gyroscope: the sensitivity and stability of the fiber optic gyroscope can be improved by reasonably designing the fiber winding structure and optical path layout.
The use of high-precision detection technology: for example, the use of high-resolution photodetectors, advanced signal processing algorithms, etc., can improve the measurement accuracy of phase difference.
Error compensation: According to the specific use of the environment and conditions, the temperature, vibration, magnetic field and other factors for error compensation to improve the measurement accuracy.
Multi-axis measurement: Using multiple fiber optic gyroscopes for multi-axis measurement can improve the measurement accuracy and reliability of the system.
Regular calibration and maintenance: Regularly calibrate and maintain the fiber optic gyro to ensure that it is in good working condition, thereby improving the measurement accuracy.
In addition, with the continuous progress of technology, new optical fiber materials, light sources and detection technologies can be used to further improve the measurement accuracy and performance of the fiber optic gyroscope. At the same time, in practical applications, it is also necessary to choose the right fiber optic gyroscope according to the specific needs and environment, and carry out reasonable installation and use to give full play to its advantages.

Ericco's fiber optic gyroscopes have long life and medium accuracy, such as ER-FOG-50, ER-FOG-60 is our very hot selling fiber optic gyroscopes, if you are interested in our products, please feel free to contact us.