• Journal of IKEEE
• /
• v.17 no.4
• /
• pp.440-445
• /
• 2013

This paper proposes a local estimation system which combines Cell Divide Algorithm with low-cost GPS/INS fused by Extended Kalman Filter(EKF) for localization of Quad-rotor when it returns to the departure point. In the research, the low-cost GPS and INS are fused by EKF to reduce the local error of low-cost GPS and the accumulative error of INS due to continuous integration of sensor error values. When the Quad-rotor returns to the departure point in the fastest path, a moving path can be known because it moves straight, where Cell Divide Algorithm is used to divide moving route into the cells. Then it determines the closest position of data of GPS/INS system fused by EKF to obtain the improved local data. The proposed system was verified through comparing experimental localization results obtained by using GPS, GPS/INS and GPS/INS with Cell Divide Algorithm respectively.

• Journal of Institute of Control, Robotics and Systems
• /
• v.11 no.8
• /
• pp.717-725
• /
• 2005

The adaptive filter is proposed for the INS/GPS. The proposed filter can estimate the variance of the process noise using the residual of the filter. To verify the efficiency of the adaptive filter, it is applied to the loosely-coupled INS/CPS that employs the additive quaternion error model. Simulation results demonstrate that the proposed filter is more effective in estimating the attitude error than EKF.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.29 no.2
• /
• pp.160-167
• /
• 2023

An INS is a composite navigation system providing "added value" so defined if work stations provide Multi-Function Displays(MFDs) integrating information and functions for navigational tasks. Even though the minimum requirements for an INS are defined by IMO performance standards, a generic list of the devices and functions that constitute an INS does not exist, so the configuration of the INS is different for each manufacturer, and guidelines based on users' perspectives are also insufficient. This study was conducted to enhance the usability of the INS by analyzing the information required by users according to the ship's operating status and tasks and effectively structuring it in the MFD of the INS. By analyzing INS-related international standards and manufacturers' component equipment lists, mandatory navigation information was selected and card sorting tests were conducted on ship operators with experience in using MFDs to group the information required for each INS task. The results of the study can serve as a basic guideline for manufacturers to structure information based on users' experience when designing products.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.34 no.10
• /
• pp.48-55
• /
• 2006

A multi-filter fusion technique is proposed and this technique is applied to the INS/GPS integrated system. IIR-type EKF and FIR-type RHKF filter are fused to provide the advantages of these filters based on the adaptive mixing probability calculated by the residuals and the residual covariance matrices of the filters. In the INS/GPS, this fusion filter can provide more robust navigation information than the conventional stand-alone filter.

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

• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1995.04a
• /
• pp.85-85
• /
• 1995

전년도에 ara-C 유도체 중에서 ara-CDP-DL-PTBA가 각종 암세포주에 대한 뛰어난 항암작용이 보고된바 있으며, 이후 시료의 대량확보, Bulk Formulation 및 전임상등의 세가지 분야에 관해 연구를 수행하였다. Ara-CDP-DL-PTBA를 수용액에 현탁, 초음파분쇄후 NICOMP Analysis에 의하여 micellar solution의 입자도를 알아 본 결과 fresh prepared micelles은 11,1mm size가 88.63%이며 50,5mm가 11.37%로 나타나 평균 19,0mm가 되고, Reconstructed micells은 10.9mm size가 99.87%이며 356.1mm가 0.13%로 나타나 평균 11.0mm가 된다. Ara-C와 Ara-CDP-DL-PTBA의 대사작용을 알아본 결과, ara-C는 투여 1시간째 2,850 $\pm$ 450 pmol, 4시간째 450$\pm$190 pmol, 24시간째 30 pmol 이하로 ara-CTP의 혈중 농도가 급격히 감소하는 반면에 ara-CDP-DL-PTBA는 1시간째 650$\pm$120 pmol, 2시간째 1,800$\pm$500 pmol, 24시간째 300$\pm$90 pmol으로 ara-CTP의 혈중 농도가 서서히 감소하였다.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
• /
• v.32 no.4_1
• /
• pp.293-298
• /
• 2014

Recently, the direct georeferencing has been becoming a common method in the aerial photogrammetry. As this direct georeferencing method using converged sensor of the digital photogrammetry camera and GPS(Global Positioning System)/INS(Inertial navaigation System), more rapid and accurate aerial photogrammetry has improved following advanced performance in photogrammetry. Since the accuracy of EO parameters from the direct georeferencing is determined by GPS/INS accuracy, it is significant to calculate the exact attitude information using values of INS rotations. For following calculations, the misalignment, such as INS rotation and the gap of GPS/INS, has to be decided. Because the number of ground control points are used for tirangulation and boresight calibration, those results should be different according to array and location of ground control points. In the study, those location and array of ground control points were tested to be used boresight calibration. As a result, there is no significant change of misalignment and exterior orienation parameters in the case when ground control points were at all course. On the contrarily, the difference has been shown in the case of no ground control point at course.

• Journal of Biosystems Engineering
• /
• v.33 no.6
• /
• pp.423-429
• /
• 2008

This study was performed to investigate the effects of inertial navigation system (INS) / global positioning system (GPS) sensor fusion for agricultural vehicle navigation. An extended Kalman filter algorithm was adopted for INS/GPS sensor fusion in an integrated mode, and the vehicle dynamic model was used instead of the navigation state error model. The INS/GPS system was consisted of a low-cost gyroscope, an odometer and a GPS receiver, and its performance was tested through computer simulations. When measurement noises of GPS receiver were 10, 1.0, 0.5, and 0.2 m ($1{\sigma}$), RMS position and heading errors of INS/GPS system at 5 m/s straight path were remarkably reduced with 10%, 35%, 40%, and 60% of those obtained from the GPS receiver, respectively. The decrease of position and heading errors by using INS/GPS rather than stand-alone GPS can provide more stable steering of agricultural equipments. Therefore, the low-cost INS/GPS system using the extended Kalman filter algorithm may enable the self-autonomous navigation to meet required performance like stable steering or more less position errors even in slow-speed operation.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.36 no.4
• /
• pp.393-398
• /
• 2008

This paper suggests a GPS/INS navigation computer architecture that can be applied to small satellites. In order to implement a GPS/INS navigation system on a small satellite, the extreme environment in space such as radiation, micro-gravity, vacuum, etc. must be considered. In addition, a real-time processing ability is required for the GPS/INS navigation system since the formation flying of multiple small satellites is the ultimate goal. The developed navigation electronics utilizes a PowerPC-type MPC860T that has space environment heritage, and a pair of Atmega128s that has been implemented in KAUSAT-2 and has completed the space environment verification tests. The navigation algorithm is designed to work in VxWorks environment, ported in MPC860T.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.35 no.3
• /
• pp.260-267
• /
• 2007

GPS adapter kit (GAK) is a GPS/INS guided range extension system to improve the accuracy and availability of existing dumb bombs. In this paper, a van test result of GPS/INS navigation module (NM) for guided bomb with GAK has been presented. The NM consists of a commercial MEMS IMU, embedded GPS receiver and navigation computer unit (NCU). The GPS receiver of NM was designed to use multiple antennas for satellite visibility and GPS attitude determination. The real-time navigation software was designed by modularized structure to guarantee the maintainability and extensibility. In order to evaluate the performance of the NM, a van test was preformed by using a high performance INS - Honeywell H-726 MAPS(Modular Azimuth Position System).The van test results show that the GAK NM with GPS attitude measurement gives better navigation performance than a conventional GPS/INS integration and good coasting capabilities under jamming environment.