The invention relates to a method for compensating the temperature error of an inertial device. The method comprises the following steps of: performing analogue-to-digital (AD) sampling on the output voltage and the power supply voltage of the inertial device simultaneously and resolving the angular velocity information of a gyroscope (or acceleration information of an accelerometer) by using theratio of two sampling values; and establishing a temperature error model of the angular velocity information (or the acceleration information) to compensate. The method has the advantages of eliminating the influences of temperature drifts of the power supply voltage of the inertial device and the reference voltage of an AD switching circuit on the output accuracy of the device, greatly simplifying the temperature error model of the inertial device and enhancing the temperature error compensation accuracy of the device.

Method for compensating temperature error of inertial device

The invention provides a positioning device and method of a coal mining machine in a full-mechanized mining face, and belongs to an autonomous positioning device and method of the coal mining machine. The positioning device of the coal mining machine is installed in a machine body, and comprises a rubber vibration damping base, a triaxial laser gyroscope, a triaxial optical fiber accelerometer, a positioning device microprocessing unit, and a positioning device anti-explosion shell , wherein the positioning device anti-explosion shell is connected above the rubber vibration damping base, and the triaxial laser gyroscope, the triaxial optical fiber accelerometer and the positioning device microprocessing unit are installed in a shell consisting of the rubber vibration damping base and the positioning device anti-explosion shell. Real-time acceleration values in three directions are measured by using the triaxial optical fiber accelerometer, and real-time angular velocities in the three directions are measured by using the triaxial laser gyroscope; thus, data of a sensor is sampled to a DSP (Digital Signal Processor) to determine the initial velocity and position, and the displacement and angular deflection of the coal mining machine along the three directions are obtained through an integral operation. The positioning device has the advantages of compact structure, simple method, safety, reliability and simplicity and convenience for installation and operation.

Positioning device and method of coal mining machine in full-mechanized mining face

This paper presents a mathematical model and a finite element model to investigate the model parameters of me- chanical dither in a ring laser gyroscope in which the bimorph piezoelectric actuator are employed as driving mechanisms to avoid the problem of so-called lock-in effects. The validity and efficiency of the mathematical model and finite element model are conformed by comparing with the sinusoidal experimental results, and the errors are 3.14% and 1.79% respectively. Moreover, the parametric design for the geometric dimensions of mechanical dither and the bimorph piezoelectric actuators is easily achieved through finite element model. It is shown that careful selection of the structural parameters allows the resonant frequency to be suitable. These results are important for the mechanical dither design and improvement of high accuracy ring laser gyroscopes and inertial navigation system.

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Parametric design of mechanical dither with bimorph piezoelectric actuator for ring laser gyroscope

Temperature is an important factor for affecting the accuracy of quartz flexible accelerometer. The relationship of quartz flexible accelerometers drift to temperature should be established accurately which can improve the precision of inertial navigation system. In order to reduce the temperature sensitivity and improve the sensor performance, temperature drift compensation method based on artificial fish swarm (AFS) algorithm is established and the steps and methods are given. The traditional modeling method of stepwise regression is also investigated to provide a comparison with the AFS algorithm. The result shows that the temperature compensation model by AFS algorithm is accurate. The drift instability of accelerometer output is reduced from 160.2ug to 18.0ug over the temperature range from-20°Cto +50°C. The results of the stochastic temperature tests show that this method has reduced the influence of temperature variation effectively and improved the accelerometer accuracy.

Temperature Drift Compensation Based on Artificial Fish Swarm Algorithm for Quartz Flexible Accelerometer

The invention aims at providing a single-axle table calibration method for a fiber optic gyro strapdown inertial navigation system. The fiber optic gyro strapdown inertial navigation system is placed on a single-axle table, the fiber optic gyro strapdown inertial navigation system is electrified for preheating, the angular velocity outputted by a fiber optic gyro and the specific force outputted by a quartz flexible accelerometer are collected, then the single-axle table is controlled to rotate at 90 degrees counter-clockwise around a rotating shaft three times, the angular velocity outputtedby the fiber optic gyro and the specific force outputted by the quartz flexible accelerometer at each time are respectively collected, and the drift of the fiber optic gyro in an x, y and z-axis coordinate system of an inertia device and the zero bias value of the quartz flexible accelerometer in the x, y and z-axis coordinate system of the inertia device are further obtained. The method can measure the drift of the fiber optic gyro and the zero bias value of the quartz flexible accelerometer by utilizing the single-axle table to rotate into different angular positions; furthermore, the calibration cost of the single-axle table is low, the steps are simple, and the single-axle table only needs to be placed on the ground during the calibration without a laboratory.

Single-axle table calibration method for fiber optic gyro strapdown inertial navigation system

The invention relate to a high-precision laser gyroscope single-shaft rotating inertial navigation system which comprises an inertial measuring unit, a single-shaft rotating platform, a circuit box, a UPS power supply, a display control device, and the like, wherein the inertial measuring unit 1 is installed on the single-shaft rotating platform 2 and carries out shock absorption by a shock absorber 3. The periodic rotation of the single-shaft rotating platform is used for modulating literal drift of an inertial device in the inertial measuring unit and improving the posture, speed and position precision of the inertial navigation system. The system concretely comprises precise installation and calibration of the inertial measuring unit, the selection of a single-shaft rotating way, precise multiposition initial alignment, the error analysis, modeling and temperature compensation of the inertial navigation system and the inertial device and a navigation algorithm of a single-shaft rotating strapdown inertial navigation system. The invention can provide a real-time, complete and high-precision navigation posture and speed and position information for a carrier (warship) for a long time and improve the comprehensive combat capability of the carrier.

High-precision laser gyroscope single-shaft rotating inertial navigation system

This paper presents an optimal structural design of dither mechanism in dithered ring laser gyroscope (DRLG) using finite element analysis (FEA). We establish an approximate theoretical model of the dithering mechanism to calculate resonant frequency and adopt the modal analysis and dynamics analysis to search the optimal solution. The validity and efficiency of the FEA are conformed by comparing with the sinusoidal and random vibration experimental results. An optimal dither mechanism is fabricated and measured experimentally. The results demonstrate the good vibration-isolated performance for the optimal design.

Finite element analysis and optimization of dither mechanism in dithered ring laser gyroscope

The invention discloses a high-precision uniaxial rotation attitude measuring system based on a laser gyro, consisting of two parts including an inertia measurement unit A and a uniaxial precise machine turntable B. In the inertia measurement unit A, a laser gyro and a quartz accelerometer are fully and rigidly coupled with a bracket, the inertia measurement device A is fixed on the uniaxial precise machine turntable B by a standard fastening bolt, the relative attitude between the inertia measurement device A and the uniaxial precise machine turntable B is precisely calibrated, and the precision and the synchronism of a solving attitude of the inertia measurement device A are guaranteed. The constant drift of an inertia device in the inertia measurement unit is modulated by the periodic rotation of the uniaxial precise machine turntable, thus the alignment precision and the navigation attitude precision of the attitude measuring system are improved. The invention can provide a carrier (a ship) with real-time and complete high-precision attitude information for a long time and improve the comprehensive combat capability of the carrier.

Jianxun Tang

Papers

High-precision laser gyroscope single-shaft rotating inertial navigation system

Finite element analysis and optimization of dither mechanism in dithered ring laser gyroscope

High-precision uniaxial rotation attitude measuring system based on laser gyro