• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.3
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• pp.368-377
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• 2009

In this paper we study the gyro bias calibration method of SDINS(Strap-Down Inertial Navigation System). Generally, SDINS's calibration is performed in 2-axis(or 3-axis) rate table with chamber for varying ambient temperature. We assumed that the majority of calibration-parameter except for gyro bias is knowned. During gyrobias calibration procedure, it can be induced some disturbances(accelerometer's short-term error induced rate table rotation and anti-vibration mount's rotation). In these cases, old gyro-bias calibration methods(using velocity error or attitude error) have an error, because these disturbances are not detectable at the same time. So that, we propose a new gyro-bias calibration method(heading error minimizing using equivalent linear transformation) that can detect anti-vibration mount's rotation. And we confirm efficiency of the new gyro-bias calibration method by simulation.

• International Journal of Aeronautical and Space Sciences
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• v.5 no.1
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• pp.83-93
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• 2004

A new alignment calibration method of attitude sensors for the precisionattitude determination of a spacecraft based on the extended Kalman filter is proposed.The proposed method is divided into two steps connected in series: the gyro and thestar tracker calibration. For gyro calibration, alignment errors and scale factor errorsare estimated during the calibration maneuver under the assumption of a perfect startracker. Estimation of the alignment errors of the star trackers and compensation ofthe gyro calibration errors are then performed using the measurements includingpayload information. Performance of the proposed method are demonstrated bynumerical simulations.

• Journal of Positioning, Navigation, and Timing
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• v.13 no.2
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• pp.179-187
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• 2024

The performance of a Strapdown Inertial Navigation System (SDINS) relies heavily on the accuracy of sensor error calibration. Systematic calibration is usually employed when only a 2-axis turntable is available. For systematic calibration, the body frame is commonly defined with respect to sensor axes for ease of computation. The drawback of this approach is that sensor axes may undergo time-varying deflection under temperature change, causing pseudo gyro bias. The effect of pseudo gyro bias on navigation performance is negligible for low grade navigation systems. However, for higher grade systems undergoing rapid temperature change, the error is no longer negligible. This paper describes in detail conditions leading to the presence of pseudo gyro bias, and proposes two techniques for mitigating the error. Experimental results show that applying these techniques improves navigation performance for precision SDINS, especially under rapid temperature change.

• International Journal of Control, Automation, and Systems
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• v.2 no.4
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• pp.536-541
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• 2004

It is important to estimate and calibrate sensor errors in maintaining the performance level of SDINS. In this study, an estimation technique of fixed sensor errors for SDINS calibration is discussed. First, the fixed errors of gyros and accelerometers, excluding gyro biases are estimated by the navigation information of SDINS in multi-position. The SDINS with RLG includes flexure errors. In this study, the gyros flexures are out of consideration, but the proposed procedure selects certain positions and rotations in order to minimize the influence of flexures. Secondly, the influences of random walks, flexures and orientation errors are verified via numerical simulations. Thirdly, applying the previous estimated errors to SDINS, the estimation of gyro biases is conducted via the additional control signals of close-loop self-alignment. Lastly, the experiments illustrate that the extracted calibration parameters are available for the improvement of SDINS.

• International Journal of Control, Automation, and Systems
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• v.4 no.3
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• pp.351-358
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• 2006

The proposed inertial measurement unit (IMU) is composed of accelerometers only. It can determine a vehicle's position and attitude, which is the Gyro-free INS. The Gyro-free INS error is deeply affected by the sensor bias, scale factor and misalignment. However, these parameters can be obtained in the laboratory. After these misalignments are corrected, the Gyro-free strap-down INS could be more accurate. This paper presents a compensator design for the strap-down six-accelerometer INS to correct misalignment. A calibration experiment is taken to get the error parameters. A simulation results show that it will decrease the INS error to enhance the performance after compensation.

• Aerospace Engineering and Technology
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• v.9 no.2
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• pp.36-43
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• 2010

A GEO satellite launched by Arian 5 ECA launcher will be located in a transfer orbit where it requires several Apogee burn maneuvers to reach the target orbit. To obtain the required performance of Apogee burn maneuvers, a calibration of gyro drift error needs to be performed before each maneuver. In this paper, a unique gyro calibration scheme which is applied to COMS is described and the calibration error budget analysis is performed.

• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.90-101
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• 2006

In this paper, the calibration parameters of the gyros and star hackers are estimated by using an on-orbit AOCS sensor calibration algorithm. The calibration algorithm was implemented by Kalman filter. In order to estimate gyro calibration parameters, the calibration algorithm requires calibration maneuver and it was analyzed whether the star trackers are protected by Sun, Moon and Earth or not. Also the star tracker calibration algorithm used the camera image information. This kinds of camera image information simulated ground control point and orbit information. The estimated accuracy of star tracker calibration parameters depends on camera image information.

• Journal of KSNVE
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• v.5 no.3
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• pp.403-411
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• 1995

Square beam type piezoelectric vibrating gyro is developed for the measurement of angular velocity, which is compact, small in size and mass- producible. It features that three pieces of piezoelectric ceramics and bonded onto one face of equilateral square bar type gyro head. Two of them are used as sentuators which drive the gyro head and measure Coriolis force. The third piece is used for the feedback signal in order to resonate the gyro head and measure Coriolis force. The third piece is used for the feedback signal in order to resonate the gyro head with its fundamental natural frequency. Matching two fundamental natural frequencies in the gyro head with its driving frequency is found critical in the design of vibration gyro. Calibration results show that the vibrating gyro developed has the dynamic characteristics of first-order system within the frequency range of interest, which can be easily compensated by a lead compensator.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.2
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• pp.189-196
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• 2019

The inertial sensor errors in SDINS(Strapdown Inertial Navigation System) can be compensated by rotating the inertial measurement unit and it is called RINS(Rotational Inertial Navigation System). It is assumed that the error of the inertial sensor in RINS is a static bias. However, the error of the inertial sensor actually developed and produced is not a static bias due to the change of the temperature applied to the sensor and the influence of the earth's gravity acceleration. In this paper, we propose a six-position gyro bias calibration method to evaluate the gyro bias required for RINS and present the test results of applying it to a ring laser gyro inertial navigation system under development.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.9
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• pp.893-897
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• 2008

To achieve the challenges of low-cost MEMS gyros for the precise self-localization of mobile robots, this paper examines an effective method of minimizing the drift on the heading angle that relies solely on integration of rate signals from a gyro. The main idea of the proposed approach is to use wavelet de-noising filter in order to reduce random noise which affects short-term performances. The proposed method was applied to Epson XV3500 gyro and the performances are verified by the comparisons with an existing commercial gyro module of vacuum cleaning robots.