• Journal of Institute of Control, Robotics and Systems
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• v.18 no.7
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• pp.632-637
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• 2012

This paper introduces a simple and efficient calibration method for three-axis accelerometers and three-axis gyroscopes using three-axis motion rate table. Usually, the performance of low cost MEMS-based inertial sensors is affected by scale and bias errors significantly. The calibration of these errors is a bothersome problem, but the previous calibration methods cannot propose simple and efficient method to calibrate the errors of three-axis inertial sensors. This paper introduces a new simple and efficient method for the calibration of accelerometer and gyroscope. By using a three-axis motion rate table, this method can calibrate the accelerometer and gyroscope simultaneously and simply. Experimental results confirm the performance of the proposed method.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6066-6071
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• 2013

This paper proposes a calibration method for a freehand 3-D ultrasound system in medical robotic research. The calibration block with six wires was designed to set the fixed target points. The positions of the ultrasound probe and calibration block were measured using an optical tracker. The relationship between the position of the ultrasound probe and the pixel coordinates in the images was derived using a calibration process. The scaling matrix was also calculated. The experimental results showed that the proposed method could find solutions using a simple least square method from one or multiple ultrasound images.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.5 s.248
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• pp.560-567
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• 2006

The exact load measurements for the mechanical parts of a wind turbine are important step both fur the evaluation of a specific wind turbine design and for a certification process. A common method for a mechanical load measurement is using a strain gauge sensing. Two main problems ought to be answered in order for this method to be applied to the wind turbine project. These are strain gauge calibration and non-contact signal transmission from the strain gauge output to a load monitoring system. This paper suggests reliable solutions fer these two problems. A Bluetooth, a short range wireless data communication technology, is used to solve the second problem. The first one, the strain gauge calibration methodology for a load measurement in a wind turbine application, is fully explained in this paper. Various mechanical loadings for a strain gauge calibration in a wind turbine load measurement are introduced and analyzed. Initial experimental results which are obtained from a 1 kW small size wind turbine are analyzed, and the uncertainty problem in estimating mechanical loads using a calibration matrix is fully covered in this paper.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.304-307
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• 1993

In this paper, we formulate Kalman filter for calibration of strapdown inertial measurment unit(SDIMU) on navigation system level and analyize its performance by covariance simulation method. It has been shown that the calibration method suggested in this paper is not largely influenced by accuracy of a mounting axis alignment required in calibration of SDIMU on IMU level.

• Journal of Institute of Control, Robotics and Systems
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• v.3 no.4
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• pp.357-362
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• 1997

This paper suggests an automatic calibration technique for piezoelectric low pressure transducer measuring a pressure blow 500psi. The present calibration system embedded with error correction algorithm generates it's best you don't cut parts of wards like so dynamic pressure and compensates offset voltage and pressure error. It is shown via experimental results that the instrumentation accuracy has been improved and mean time between calibrations has been shortened.

• Journal of applied mathematics & informatics
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• v.11 no.1_2
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• pp.327-340
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• 2003

For motion analysis electromagnetic sensors are often used to measure positions and orientations of human subjects. It is observed from several experiments of the Ergonomics Research group that there exist systematic errors and unexpected serious distortions due to some metal masses in the test area. A calibration process is necessary to fix these errors. In this article three models are proposed to correct position measurement errors based on observations from calibration experiments.

• Journal of Korean Society on Water Environment
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• v.36 no.6
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• pp.568-580
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• 2020

Calibrating a conceptual hydrologic model necessitates selection of a calibration period that produces the most reliable prediction. This often must be chosen randomly, however, since there is no objective guidance. Observation plays the most important role in the calibration or uncertainty evaluation of hydrologic models, in which the key factors are the length of the data and the hydro-climate conditions in which they were collected. In this study, we investigated the effect of the calibration period selected on the predictive performance and uncertainty of a model. After classifying the inflows of the Hapcheon Dam from 1991 to 2019 into four hydro-climate conditions (dry, wet, normal, and mixed), a conceptual hydrologic partitioning model was calibrated using data from the same hydro-climate condition. Then, predictive performance and post-parameter statistics were analyzed during the verification period under various hydro-climate conditions. The results of the study were as follows: 1) Hydro-climate conditions during the calibration period have a significant effect on model performance and uncertainty, 2) calibration of a hydrologic model using data in dry hydro-climate conditions is most advantageous in securing model performance for arbitrary hydro-climate conditions, and 3) the dry calibration can lead to more reliable model results.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1359-1364
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• 2008

It is well known that the standard penetration test (SPT) has been used in all over the world to get geotechnical properties of the ground. However, it is difficult to apply the SPT to the dense sand, gravel, weathered rock, etc. For the application of the SPT in these grounds, it is necessary to change in the diameter and the impact energy of the SPT. For the improvement of site investigation technology, Large Penetration Testing device (KICT-type LPT) was developed and applied to the in situ condition. The drop height and weight of the hammer in developed system were decided as 760mm and 150kg, respectively. And the developed sampler has the inner diameter of 63 mm and the length of 500 mm with the adjustment of energy ratio to the SPT of 1.5. In this study, the performance of KICT-type LPT was evaluated by using a calibration chamber system and pile driving analyzer (PDA)

• The Bulletin of The Korean Astronomical Society
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• v.46 no.2
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• pp.76.1-76.1
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• 2021

Maemi Dual Field Telescope System (MDFTS) is a dual telescope system located at Kyung Hee University. The system consists of 0.4 m telescope and 0.1 m telescope for wide-field observation. The 0.4 m telescope provides photometric observation which covers a field of view of 21'×16'. It has been used for various purposes with Johnson-Cousins UBVRI broadband filter system, e.g., SomangNet and Intensive Monitoring Survey of Nearby Galaxies. In this poster, we present the standard calibration result for our broadband filter system. Also, we suggest a new usage of the KHAO 0.4m telescope which is narrowband photometry by demonstrating the standard calibration of H-alpha filter. For flux calibration, not only R filter but also V filter is used for compensating the central wavelength discrepancy between R filter and H-alpha filter.

• Journal of Internet Computing and Services
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• v.6 no.5
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• pp.57-71
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• 2005

Precise visual measurement applications, like video measuring system (VMS), use camera systems with motorized zoom lens for fast and efficient measurement. In this paper, we introduce an efficient calibration method for zoom lens of VMS controlled by servo motor. For the automated zoom lens calibration of the VMS, only zoom lens setting needs to be calibrated and parameters calibrated by zoom lens settings are image center and pixel size changed by zoom levels, The extrinsic parameters, like focus and iris, do not need to be calibrated since the parameters are usually fixed, It needs a lot of time and effort to calibrate the camera for ali the different zoom levels. In this paper, we also propose an efficient and fast zoom lens calibration method, which calculates the calibration parameters of the zoom lens settings for the minimum number of zoom levels and estimates other parameters for the uncalculated zoom levels using the interpolation of the calculated parameter values.