본 연구는 가선집재시스템에서 벌도목을 견인 시작 지점에서 Yarder까지 안전하게 운반할 수 있는 최대 하중인 가선경로상의 허용반송량을 분석하여, 가선집재 작업에 필요한 의사결정을 지원하기 위한 목적으로 수행되었다. 이를 위해 허용반송량의 변화를 예측하는 모델을 구현하고, 가선집재시스템 구동에 주요 인자인 지형조건, Yader의 높이, 가선의 직경, 벌도목의 견인형태 및 작업방식에 대한 민감도 분석을 수행하였다. 분석결과, 가선 설치계획에 있어 오목한 지형을 선택하는 것이 안전성과 효율성에 중요한 영향을 미치는 것을 확인할 수 있었고 Yarder의 높이나 Wire rope의 직경, 벌도목의 견인형태 및 시스템의 작업방법과 같은 시스템을 구성하는 여러 요인에 의해 작업 생산량이 달라지는 것을 확인하였다. 이러한 결과는 가선의 설치경로에 대한 허용반송량 분석의 필요성과 시스템의 다양한 구동 요인에 대한 평가가 가선집재시스템의 국내 현장 적용 및 보급에 필요함을 보여준다.

In this study, system modeling and dynamic analysis of crane are conducted. Especially, among many different kinds of a crane system, the issues on crane operating problems installed on the vessel are considered. As well known, marine systems including cranes are exposed to various disturbances such as vessel motions, hydrodynamic forces, wave and wind attack, etc. In order to analysis the system dynamic with environmental conditions, the authors derived the nonlinear dynamic model of offshore crane and derived a linear model which is used for designing the control system. Using the obtained nonlinear and linear models, simulations were conducted to evaluate the usefulness of the obtained models. By simulation and result evaluation, the usefulness of the linear model, which presents the dynamics, is effectively verified.

This study proposes the compensation method for the mechanical deflection error of a SCARA robot. While most studies on the related subject have dealt with the development of a control algorithm for improvement of robot accuracy, this study presents the control method reflecting the mechanical deflection error which is predicted in advance. The deflection at the end of the gripper of SCARA robot is caused by the self-weights and payloads of Arm 1, Arm 2 and quill. If the deflection is constant even though robot’ posture and payload vary, there may not be a big problem on robot accuracy because repetitive accuracy, that is relative accuracy, is more important than absolute accuracy in robot. The deflection in the end of the gripper varies as robot’ posture and payload change. That’ why the moments ,  and  working on every joint of a robot vary with robot’ posture and payload size. This study suggests the compensation method which predicts the deflection in advance with the variations in robot’ posture and payload using neural network. To do this, I chose the posture of robot and the payloads at random, found the deflections by the FEM analysis, and then on the basis of this data, made compensation possible by predicting deflections in advance successively with the variations in robot’ posture and payload through neural network learning.

We have preliminarily designed two infrared optical systems of the multi-purpose infrared camera system (MIRIS) which is the main payload of STSAT-3. Each optical system consists of a Cassegrain telescope, a field lens and a 1:1 re-imaging lens system that is essential for providing a cold stop. The Cassegrain telescope is identical for both of two infrared cameras, but the field correction lens and re-imaging lens system are different from each other because of different bands of wavelength. The effective aperture size is 100mm in diameter and the focal ratio is f/5. The total length of the optical system is 300mm and the position of the cold stop is 25mm from the detector focal plane. The RMS spot size is smaller than 40μm over the whole detector plane.

Inspired by small insects, which perform rapid and stable locomotion based on body softness and tripod gait, various milli-scale six-legged crawling robots were developed to move rapidly in harsh environment. In particular, cockroach’s leg compliance was resembled to enhance the locomotion performance of the crawling robots. In this paper, we investigated the effects of changing leg compliance for the locomotion performance of the small light weight legged crawling robot under various payload condition. First, we developed robust milli-scale six-leg crawling robot which actuated by one motor and fabricated in SCM method with light and soft material. Using this robot platform, we measured the running velocity of the robot depending on the leg stiffness and payload. In result, there was optimal range of the leg stiffness enhancing the locomotion ability at each payload condition in the experiment. It suggests that the performance of the crawling robot can be improved by adjusting stiffness of the legs in given payload condition.

Robot arms are being increasingly used in various fields with special attention given to unmanned systems. In this research, we developed a high payload dual-arm robot, in which the forearm module is replaceable to meet the assigned task, such as object handling or lifting humans in a rescue operation. With each forearm module specialized for an assigned task (e.g. safety for rescue and redundant joints for object handling task), the robot can conduct various tasks more effectively than could be done previously. In this paper, the design of the high payload dual-arm robot with replaceable forearm function is described in detail. Two forearms are developed here. Each of forearm has quite a different goal. One of the forearms is specialized for human rescue in human familiar flat aspect and compliance parts. Other is for general heavy objects, more than 30 kg, handling with high degree of freedom more than 7.