• International Journal of Precision Engineering and Manufacturing
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• v.3 no.3
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• pp.5-11
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• 2002

This paper describes the methods for calibration and evaluation of the relative expanded uncertainty of a multi-axis force/moment sensor. In order to use the sensor in the industry, it should be calibrated and its relative expanded uncertainty should be also evaluated. At present, the confidence of the sensor is shown with only interference error. However, it is not accurate, because the calibrated multi-axis force/moment sensor has an interference error as well as a reproducibility error of the sensor, etc. In this paper, the methods fur calibration and for evaluation of the relative expanded uncertainty of a multi-axis force/moment sensor are newly proposed. Also, a six-axis force/moment sensor is calibrated with the proposed calibration method and the relative expanded uncertainty is evaluated using the proposed uncertainty evaluation method and the calibration results. It is thought that the methods fur calibration and evaluation of the uncertainty can be usually used for calibration and evaluation of the uncertainty of the multi-axis force/moment sensor.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.2 s.95
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• pp.176-182
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• 1999

This paper presents a new autonomous kinematic calibration technique by using a laser-vision sensor called "Perceptron TriCam Contour". Because the sensor measures by capturing the image of a projected laser line on the surface of the object, we set up a long, straight line of a very fine string inside the robot workspace, and then allow the sensor mounted on a robot to measure the point intersection of the line of string and the projected laser line. The point data collected by changing robot configuration and sensor measuring are constrained to on a single straght line such that the closed-loop calibration method can be applied. The obtained calibration method is simple and accurate and also suitable for on-site calibration in an industrial environment. The method is implemented using Hyundai VORG-35 for its effectiveness.

• International Journal of Precision Engineering and Manufacturing
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• v.4 no.1
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• pp.43-48
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• 2003

A linear laser-vision sensor called ‘Perception TriCam Contour' is mounted on an industrial robot and often used for various application of the robot such as the position correction and the inspection of a part. In this paper, a sensor center position calibration is presented for the most accurate use of the robot-Perceptron system. The obtained algorithm is suitable for on-site calibration in an industrial application environment. The calibration algorithm requires the joint sensor readings, and the Perceptron sensor measurements on a specially devised jig which is essential for this calibration process. The algorithm is implemented on the Hyundai 7602 AP robot, and Perceptron's measurement accuracy is increased up to less than 1.4mm.

• Journal of Korea Society of Industrial Information Systems
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• v.15 no.2
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• pp.83-90
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• 2010

Sensor is a key element in various fields of applications such as sensor networks. However, they could not be easily developed because of several factors such as temperature dependence of output characteristics and/or nonlinearity. Calibration of sensor is also needed to solve these problems. Conventional calibration process required a lot of time and expenses. Therefore, it is important to develop sensor systems which can shorten development time and minimize expense. In this paper, we develop CO and $CO_2$ Sensor modules and propose a multiple sensor calibration system to resolve problems of conventional calibration process. A proposed system is composed of sensor module, system board and monitor program. Regression analysis method based on the least mean squares is used for calibration. We introduced the structure of calibration systems and experimental results. Calibration results can be used to confirm the effectiveness of the proposed system.

• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.4
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• pp.491-499
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• 2009

The determination of response characteristics for pressure sensors is routinely limited to static calibration against a deadweight pressure standard. The strength of this method is that the deadweight device is a primary standard used to generate precise pressure. Its weakness lies in the assumption that the static and dynamic responses of the sensor in question are equivalent. Differences in sensor response to static and dynamic events, however, can lead to serious measurement errors. Dynamic techniques are required to calibrate pressure sensors measuring dynamic events in milliseconds. In this paper, a dynamic calibration using negative going dynamic pressure is proposed to determine dynamic pressure response for piezoelectric sensors. Sensitivity and linearity of sensor by the dynamic calibration were compared with those by the static calibration. The uncertainty of calibration results and the goodness of fit test of linear regression analysis were presented. The results show that the dynamic calibration is applicable to determine dynamic pressure response for piezoelectric sensors.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.12
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• pp.1267-1271
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• 2014

There have been many autonomous robot calibration methods which form closed loop structures through the various attached sensors and mechanical fixtures. Single point calibration among them has been used for on-site calibration due to its convenience of implementation. The robot can reach a single point with infinitely many configurations so that single point calibration algorithm can be set up and easily implemented relative to the other methods. However, it is not still easy to drive the robots' sharp edge to its corresponding edge of the fixture. This is error-prone process. In this paper, we propose a 3 dimensional small displacement measuring sensor and a robot calibration algorithm based on this sensor. This method relieves the difficulty of matching two edges in the single point calibration and improves the resulting robot accuracy. Simulated study is carried out on a Hyundai HA06 robot to show the effectiveness of the proposed method over the single point calibration. And also, the resulting robot accuracy is compared with that from 3D laser tracker based calibration to show the dependency of robot accuracy on range of the workspace where the measurement data are collected.

• Journal of the Korean Solar Energy Society
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• v.38 no.6
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• pp.65-72
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• 2018

Since data-driven building technologies have been widely applied to building energy systems, the accuracy of building sensors has more impacts on the building performance and system performance analysis. Various building sensors, however, can have typical errors including a random error (noise) and a systematic error (bias). The systematic error is indicated by the difference between the mean of measurements and their true value. It may occur due to the sensor's physical condition, measured phenomena, working environments inside the systems. Unfortunately, a conventional calibration method has limitations in calibrating the systematic errors because of the difference between working environments and calibration conditions. In such situations, a novel sensor calibration method is needed to handle various sensor errors, especially for systematic errors, in building energy systems having various thermodynamic environments. This study proposes a building sensor calibration method named Virtual In-situ Calibration (VIC) and shows how it is applied into a real building system and how it solves the sensor errors.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10b
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• pp.527-530
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• 1996

The Kalman filter has been used as a self-localization method for the mobile robot. To satisfy the assumptions inherent in the Kalman filter, we should calibrate the sensors of the robot before use of them. However, it is generally hard to find exact sensor parameters, and the parameters may change during the robot task as the environment varies. Thus we need to perform on-line sensor calibration, by which we can obtain more credible location of the mobile robot. In this paper, we present an on-line sensor calibration scheme which estimates the unknown sensor bias and the current position of the robot. To this end, first we find out the calibration errors of the sensor from redundant sensory data using the parity vector and recursive minimum variance estimation. Then we calculate the current position of the robot by weighted least square estimation without internal encoder data. The performance of the proposed method is evaluated through computer simulation.

• Journal of the Korea Society of Computer and Information
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• v.21 no.11
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• pp.1-7
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• 2016

In this paper, we proposed real-time relative radiometric calibration processing method for SWIR(Short Wavelength Infra-Red) sensor using 'Hyper-Spectral Imager'. Until now domestic research for Hyper-Spectral Imager has been performing with foreign sensor device. So we have been studying hyper spectral sensor device to meet domestic requirement, especially military purpose. To improve detection & identify capability in 'Hyper-Spectral Imager', it is necessary to expend sensing wavelength from visual and NIR(Near Infra-Red) to SWIR. We aimed to design real-time processor for SWIR sensor which can control the sensor ROIC(Read-Out IC) and process calibrate the image. To build Hyper-Spectral sensor device, we will review the SWIR sensor and its signal processing board. And we will analyze relative radiometric calibration processing method and result. We will explain several SWIR sensors, our target sensor and its control method, steps for acquisition of reference images and processing result.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.10
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• pp.91-98
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• 2007

This paper describes the development of the calibration system for a multi-axis force/moment sensor and its uncertainty evaluation. This calibration system can generate the continuous forces (${\pm}Fx,\;{\pm}Fy$ and ${\pm}Fz$) and moments (${\pm}Mx,\;{\pm}My$ and ${\pm}Mz$). Many kinds of multi-axis force/moment sensors in industries should be carried out the characteristic test or the calibration with the calibration system that can generate the forces and the moments. The calibration systems have been already developed are the disadvantages of the low capacity, the generation of step forces(10N, 20N ...) and step moments(1Nm, 2Nm ...) with weights, the high coasts in manufacture and so on. In this paper, the calibration system for a multi-axis force/moment sensor that can generate the continuous three forces and three moments was developed. Their ranges are $0{\sim}2000N$ in all force-directions and $0{\sim}400Nm$ in all moment-directions. And the system was evaluated in the expanded relative uncertainty. They were ${\pm}0.0004$ in all forces ${\pm}Fx,\;{\pm}Fy$ and ${\pm}Fz$, and ${\pm}0.0004$ in all moments ${\pm}Mx,\;{\pm}My$ and ${\pm}Mz$.