• Proceedings of the Optical Society of Korea Conference
• /
• 2003.07a
• /
• pp.270-271
• /
• 2003

링 레이저 자이로스코프는 회전각을 검출하는 센서로서 광학식이 가지는 정밀함과 견고성으로 관성항법을 비롯한 운동 제어를 필요로 하는 여러 분야에서 기존의 기계식 자이로스코프를 대체해 오고 있다. 링 레이저 자이로는 세 개 또는 네 개의 반사경으로 밀폐된 고리형 공진기를 구성하고 He-Ne 기체를 봉입하여 방전시킴으로써 서로 반대 방향으로 진행하는 레이저를 동시에 발진시키면 Sagnac 효과에 의해 공진기의 회전각에 비례하여 두 레이저의 주파수 차이가 발생하는 원리를 이용한다. (중략)

• Korean Journal of Optics and Photonics
• /
• v.5 no.1
• /
• pp.131-137
• /
• 1994

We demonstrate a novel mode locked fiber laser gyroscope that utilizes a rare-earth doped fiber. The output of the gyroscope is a series of short optical pulses. Without rotation, the optical pulses are equally spaced in the time domain. With rotation, the intervals of the optical pulses changes. By measuring the separation of the optical pulses in time domain, the rotation rate could be obtained. We also discuss the polarization effect that can cause signal errors.errors.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.40 no.2
• /
• pp.397-407
• /
• 2015

In this paper, we designed 1 chip IC for 3-axis gyroscope and 3-axis accelerometer used for various IoT/M2M mobile devices such as smartphone, wearable device and etc. We especially focused on analysis of gyroscope noise and proposed new architecture for removing various noise generated by gyroscope MEMS and IC. Gyroscope, accelerometer and geo-magnetic sensors are usually used to detect user motion or to estimate moving distance, direction and relative position. It is very important element to designing a low noise IC because very small amount of noise may be accumulated and affect the estimated position or direction. We made a mathematical model of a gyroscope sensor, analyzed the frequency characteristics of MEMS and circuit, designed a low noise, compact and low power 1 chip 6-axis inertial sensor IC including 3-axis gyroscope and 3-axis accelerometer. As a result, designed IC has 0.01dps/${\sqrt{Hz}}$ of gyroscope sensor noise density.

• Proceedings of the Optical Society of Korea Conference
• /
• 2003.07a
• /
• pp.272-273
• /
• 2003

링레이저 자이로스코프(Ring Laser Gyroscope-이하 RLG)는 비행기, 유도무기, 선박, 지상무기 등의 관성항법장치(Inertial Navigation System)에 사용되는 각속도 센서로서 항체의 위치와 자세 정보를 제공하는 핵심 구성품 중의 하나이다. 각속도 검출 원리는 삼각형 또는 사각형의 공진기에 He과 Ne을 혼합한 이득매질을 사용하여 서로 반대방향으로 회전하는 두 개의 레이저 빔을 발생시켜서 Sagnac 효과에 의해 외부의 회전 입력을 받을 때 서로 다른 광 경로의 차이로 인한 두 빔의 간섭으로 회전각을 검출한다. (중략)

• Transactions of the Korean Society for Noise and Vibration Engineering
• /
• v.14 no.1
• /
• pp.64-72
• /
• 2004

In this paper. we analyse and present electro-mechanical dynamic characteristics of a micro-machined vibrating silicon ring gyroscope which can measure angular velocities about three orthogonal axes. The ring gyroscope has a ring connected to the gyroscope main body by support-ligaments which are arranged with cyclic symmetry. The natural modes of its vibration can be distinguished into the in-plane motion and the out-of-plane motion which are coupled by the gyro-effect due to the rotation of the gyroscope main body. The motions of the ring are electro-statically derived. sensed and balanced by electrodes. The equations of motion are formulated. The measuring method of angular velocities by force-to-rebalance is presented. The dynamic characteristics of a ring gyroscope are calculated and compared.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
• /
• 2003.11a
• /
• pp.970-976
• /
• 2003

In this paper, we analyse and present electro-mechanical dynamic characteristics of a micro-machined vibrating silicon ring gyroscope which can measure angular velocities about three orthogonal axes. The ring gyroscope has a ring connected to the gyroscope main body by support-ligaments which are arranged with cyclic symmetry. The natural modes of its vibration can be distinguished into the in-plane motion and the out-of-plane motion which are coupled by the gyro-effect due to the notation of the gyroscope main body. The motions of the ring are electro-statically derived, sensed and balanced by electrodes. The equations of motion are formulated. The scheme of angular velocities sensing by force-to-rebalance method is presented. The dynamic characteristics of a ring gyroscope are calculated and compared.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.21 no.4
• /
• pp.518-524
• /
• 2011

This paper presents a study on the calibration of accelerometer data in the gyroscope free inertial navigation system(GFINS) using fuzzy inference system(FIS). The conventional INS(inertial navigation system) which can measure yaw rate and linear velocity using inertial sensors as the gyroscope and accelerometer. However, the INS is difficult to design as small size and low power because it uses the gyroscope. To solve the problem, the GFINS which does not have the gyroscope have been studied actively. However, the GFINS has cumulative error problem still. Hence, this paper proposes Fuzzy-GFINS which can calibrate the data of an accelerometer using FIS consists of two inputs that are ratio between linear velocity of the autonomous ground vehicle(AGV) and the accelerometer and ratio between linear velocity of the encoders and the accelerometer. To evaluate the proposed Fuzzy-GFINS, we made the AGV with Mecanum wheels and applied the proposed Fuzzy-GFINS. In experimental result, we verified that the proposed method can calibrate effectively data of the accelerometer in the GFINS.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2003.05a
• /
• pp.370-373
• /
• 2003

Superluminescent diodes(SLDs) are the optimum light sources for application in optical measurement systems such as fiber gyroscopes, optical time domain reflectometers, and to short and medium distance optical communication systems. The broadband characteristics of SLDs reduce Rayleigh backscattering noise, polarization noise, and the bias offset due to the nonlinear Kerr effect in fiber gyro systems. In this paper, in order to suppress lasing oscillation, we introduced a laterally tilted SCH(Separate Confinement Heterostructure)-SLD with a window region. An output power of 11mW has been achieved at 200mA injection current at 25$^{\circ}C$. At 120mA, parallel and perpendicular to the junction were 31$^{\circ}$${\times}$38$^{\circ}$.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.2
• /
• pp.58-63
• /
• 2000

The dynamics of spindle-bearing-workpiece system significantly affects the cutting condition and stability in milling process. The present paper investigates the chatter stability of milling process due to the change in the dynamics of spindle-bearing-workpiece systems. In particular, the present paper focuses on chatter stability due to the presence of gyroscopic effect. An eigenvalue problem approach to the stability of milling process is extensively used in this paper. To incorporate the rotational speed dependent gyroscopic effect, an iterative algorithm is proposed. A numerical example is provided for examining the chatter stability problem in the presence of gyroscopic effects.

• Journal of Navigation and Port Research
• /
• v.40 no.6
• /
• pp.361-368
• /
• 2016

A ship's rolling motion can make crew and passengers sick and/or apply forces to the structure that cause damage.. Therefore bilge keels are equipped in most ships for anti-rolling. In special cases, anti-rolling tanks (ARTs), fin stabilizers, or gyroscopes can be installed. However, ARTs require a large area to install, and fin stabilizers and gyroscopes are costly to install and expensive to operate. This paper suggests a Anti-rolling pendulum (ARP) to reduce roll motion. ARPs acts like ARTs. However, the ARP has a circular shaped guidance arc instead of the string or wire of a simple pendulum. The device suggested has about 1/ 8 the weight and 1/ 6 the volume of a ART and is more effective. This study derives the nonlinear and linear differential equations of system motion.