Inertial Measurement Technology And Monitoring Navigation Technology Of Atom Interference Gyroscope

Inertial navigation is an important positioning method without external information sources and is of great significance in the military and civilian fields.Gyroscopes and accelerometers are the measurement units of the inertial navigation system.The accuracy of devices determines the positioning accuracy of the inertial navigation system,and the data-rate and stability of the devices are critical to system performance.As a representative of the quantum devices,the atom interference gyroscope is a new type of gyroscope with the highest expected accuracy.It is the first choice to improve the positioning precision of unmanned underwater vehicles.However,due to insufficient research on error analysis and noise suppression of atom interference gyroscope in the laboratory,its measurement accuracy cannot meet the navigation needs.And due to the lack of data-rate and measurement stability,atom interference gyroscope mostly used for single-axis constant measurements.It can be seen that the atom interferometer as rotation measuring device provides a new technical approach for the long-haul autonomous navigation system of unmanned underwater vehicle,it is a frontier topic in the field of inertial navigation.In recent years,with the advancement of related technologies in the field of optics and physics,the stability of the atom interference gyroscope has been greatly improved.However,based on the peculiarity of its principle,the existing gyro test methods cannot achieve accurate characteristic test.At the same time,the atom interference gyroscope lacks feasibility demonstration as a dynamic rotation measuring instrument.The feasibility demonstration and the key parameter test of the gyro are the necessary steps from the measurement of the laboratory constant to the actual inertial navigation application,and also the basis for the reliable operation of the underwater unmanned vehicle test and navigation process.In-depth study of the gyroscope data characteristics and system mechanism,correspondingly explore a more reliable gyro test method,which is of great significance for guiding the gyro performance improvement direction.However,there are few reports on this.This dissertation puts forward the targeted system noise model and achieves accurate suppression by studying the mechanism of the atom interference gyroscope and its main error and noise sources.At the same time,it simulates and experimentally studies the application scenarios of the inertial navigation system.The thesis has carried out indepth theoretical and experimental research in the above aspects,the main contents are as follows:Firstly,the noise mechanism is studied for the problems of the atom interference gyroscope as a rotating measuring instrument.An energy spectrum analysis method based on phase-changed function is proposed,and the problem that the existing solution cannot analyze the phase noise of specific frequency.The reliable phase noise analysis and compensation are achieved,and accurately quantified the statistical variance of its influence on the measurement results.Furthermore,the influence of mirror vibration noise on the interferometry process is analyzed from the mechanism,and the conversion of environmental disturbances to phase noise is realized,and quantitative evaluation and real-time compensation are achieved by phase-changed function method.The suppression effect of the vibration isolation system on the vibration noise of the mirror and its influence on the system are further analyzed.The test results show that the active vibration isolation system brings about 10% improvement compared with the passive vibration isolation platform.The simulation can help us select appropriate vibration isolation parameters to achieve better vibration noise suppression.Secondly,the maturity of the atom interference gyro system is insufficient,and lack of research on the feasibility study and evaluation methods on the dynamic measurement of atom interference gyro for inertial navigation systems.Based on the principle of atom interferometer and the mechanism of the system,key parameters and test plans are presented refer to the national military standard for fiber optic gyro and laser gyro,IEEE test plan,Allan analysis of variance,etc.Based on the test conclusion,the accurate calculation of the data-rate and scale factor of the atom interference gyroscope is realized.And the feasibility of the atom interference gyro system for dynamic inertial measurement is demonstrated.That is,when the atom interference gyro double-loop output signal-to-noise ratio is better than 30dB,the double-loop differential phase error is about 1%,and the rotation measurement accuracy is better than 0.001°/h.Third,for the long-haul application of underwater unmanned vehicles,three improved Allan variance methods are proposed by utilizing the laboratory data of atom interference gyros in recent years.A random noise simulation model of atom interference gyro is established.And installation error,scale factor error,gyro zero error,and other considerations are added,the random noise simulation model and dynamic model of the atom interference gyro are realized.The construction of the simulation environment provides data support for the inertial navigation system simulation and provides engineering application guidance for the performance improvement,noise evaluation,and compensation of the atom interference gyroscope.Finally,there are two major shortcomings for the atom interference gyroscope in the process of establishing an inertial navigation system:the lack of data-rate and the problem of multi-axis simultaneous measurement.A new monitoring navigation scheme is proposed here.The fiber INS achieves a significant increase in positioning accuracy after the atom interference gyroscope is attached.In the MATLAB environment,a monitoring navigation system based on single-axis,or triaxial atom interference gyroscope and fiber inertial measurement unit is established,the actual positioning effect of this monitoring model is verified by the vehicle test and the sea test of different precision fiber inertial measurement units,which shows that the velocity accuracy and positioning accuracy are greatly improved.This monitoring navigation scheme fully exploits the stability advantages of atom interference gyroscopes and provides a new equipment solution for the long-haul positioning system of unmanned underwater vehicles.