• Smart Structures and Systems
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• 제1권1호
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• pp.13-27
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• 2005

Simultaneous precision positioning and vibration suppression of a reciprocating flexible manipulator is investigated in this paper. The flexible manipulator is driven by a multifunctional active strut with fuzzy logic controllers. The multifunctional active strut is a combination of a motor assembly and a piezoelectric stack actuator to simultaneously provide precision positioning and wide frequency bandwidth vibration suppression capabilities. First, the multifunctional active strut and the flexible manipulator are introduced, and their dynamic models are derived. A control strategy is then proposed, which includes a position controller and a vibration controller to achieve simultaneous precision positioning and vibration suppression of the flexible manipulator. Next, fuzzy logic control approach is presented to design a fuzzy logic position controller and a fuzzy logic vibration controller. Finally, experiments are conducted for the fuzzy logic controllers and the experimental results are compared with those from a PID control scheme consisting of a PID position controller and a PID vibration control. The comparison indicates that the fuzzy logic controller can easily handle the non-linearity in the strut and provide higher position accuracy and better vibration reduction with less control power consumption.

• 한국정보과학회논문지:시스템및이론
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• 제33권4호
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• pp.205-215
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• 2006

LCB 타블렛과 타블렛 PC 등과 같은 펜-입력 디스플레이는 CAD에서, 특히, 컨셉트 디자인 단계에서 유용하게 사용될 수 있다. 본 논문에서는, 이런 장치들을 대상으로 하는 CAD 시스템에서 사용될 수 있는 직관적인 B-Spline 수정 방법을 제안한다. 컨트롤 포인트를 기반으로 하는 B-Spline 수정 방법과는 달리, 본 논문에서 제안한 방법은 곡선이나 곡면의 최종적인 모양을 결정하는데 사용자의 펜 입력을 이용한다. 이전에 방법에서 컨트롤 포인트나 조작자(manipulator)를 이용했던 것에 비해 원하는 모양을 만들어 가는 데 소요되는 시간을 줄여준다. 이런 과정은 디자인을 하는데 있어서 지금까지는 피할 수 없는 것처럼 여겨져 왔다. 본 논문에서 제시된 방법의 용이성을 검증하기 위하여 여러 명의 디자이너들과 함께 실험을 수행한 결과를 보여준다.

• 한국통신학회논문지
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• 제14권5호
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• pp.486-502
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• 1989

본 논문에서는 로보트 매니퓰레이터의 정밀한 경로 제어를 위해서, 두가지 형태의 로보트 관절 각도 및 관절 속도의 예측 알고리즘을 제시하고, 이를 이용한 제어 방법을 기술하고자 한다. 구체적으로, 로보트 메니퓰레이터의 동특성을 Computed torque방법으로 선형화 시킨후에, 선형화된 모델을 근거로 한 이산시간 상태변수 예측기를 제안한다. 또한, 현재의 관절 위치 및 관절 속도와 과거 및 개의 위치 및 속도 등을 최소 자승법의 의미로 가장 잘 부합시키는 직선을 찾고, 그 직선으로부터 상태를 예측하는 예측기를 제안한다. 이 후에 이들 두 예측기로부터 정보를 이용하여, 예측된 궤적과 원하는 궤적 사이의오차에 적절한 이득을 곱해서 입력 토오크에 보정되어 사용됨으로써 궤적 오차를 줄일 수 있음을, 2자유도를 갖는 SCARA 로보트를 대상으로 컴퓨터 모의 실험을 통하여 보이고자 한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.61-64
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• 1996

This paper presents a new approach to the design of self-tuning adaptive control system that is robust to the changing dynamic configuration as well as to the load variation factors using Digital signal processors for robot manipulators. TMS32OC50 is used in implementing real-time adaptive control algorithms to provide advanced performance for robot manipulator. In this paper, an adaptive control scheme is proposed in order to design the pole-placement self-tuning controller which can reject the offset due to any load disturbance without a detailed description of robot dynamics. Parameters of discrete-time difference model are estimated by the recursive least-square identification algorithm, and controller parameters are determined by the pole-placement method. Performance of self-tuning adaptive controller is illustrated by the simulation and experiment for a SCARA robot.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2226-2230
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• 2005

The Advanced Spent Fuel Conditioning Process (ACP), which is a pre-disposal treatment process for spent fuel is being developed at the Korea Atomic Energy Research Institute (KAERI). The ACP equipment is operated in an intense radiation field as well as in a high temperature. Thus, the equipment is designed in consideration of the remote handling and maintenance. This paper describes a Bridge Transported Bilateral Force-Reflecting Servo-Manipulator (BTSM) system, which is being developed to overcome the limitation of access that is a drawback of the mechanical Master-Slave Manipulators (MSMs), which are mounted on the ACP hot cell wall for the operation and the maintenance of the ACP equipment. The BTSM system was manufactured and temporally installed at the mockup to test its performance. The manufactured BTSM system will be installed at the ACP hot cell on June 2005 after the accomplishment of the performance test. The BTSM system consists of four components: a transporter with a telescoping tubeset, a slave manipulator, a master manipulator, and a remote control system. This system will highly increase the volume of coverage for the operation and maintenance of the ACP equipment.

• 제어로봇시스템학회논문지
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• 제15권10호
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• pp.1039-1046
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• 2009

In this work, a bilateral control for a master-slave manipulator system which will be used for handling objects contaminated by radioactivity has been addressed. The links of manipulators are driven independently by individual motors installed on the base and the driving torque is transmitted through pre-tensioned tendons. The measurable variables are the positions and rates of master/slave motors. In the consideration of the flexibility of the tendon and available measurements for control, we proposed an optimal static output feedback control for possible bilateral control architecture. By using modal analysis, the system model is reduced to guarantee the detectability which is a necessity for the static output feedback control design. Based on the reduced model, the control gains are determined to attenuate vibration in the sense of optimality. The feasibility of the proposed control design was verified along with some simulation results.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.373-376
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• 2001

In this paper to cope with the reduction of products life-cycle as the variety of products along with the various demands of consumers, a virtual simulator is developed to make the changeover of manufacturing line efficient to embody a virtual simulation similar to a real manufacturing line. The developed virtual simulator can design a layout of a factory and make the time scheduling. Every factory has one simulator so that one product can be manufactured in the factories to use them as virtual factories. We suggest a scheme that heightens the ability to the diversity of manufacturing models by making the information of manufacturing lines and products models to be shared. The developed system embodies a virtual manufacturing line on the simulation using various manipulators and work cells as manufacturing components. we develop a virtual simulator system on Window 98/NT environment of Microsoft, operating system using of the greater part of PC user. Window program have a merit making GUI environment that programmer can use without the expert knowledge about hardware. A suer with the simulator can utilize an interface that makes one to manage the separate task process for each manufacturing module, change operator components and work cells, and easily teach tasks of each task module.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1997년도 추계학술대회 학술발표 논문집
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• pp.111-114
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• 1997

Usually, Evolutionary Algorithms are considered more efficient for optimal system design, However, the performance of the system is determined by fitness function and system environment. In this paper, in order to overcome the limitation of the performance by this factor, we propose a co-evolutionary method that two populations constantly interact and coevolve. In this paper, we apply coevolution to neural network's evolving. So, one population is composed of the structure of neural networks and other population is composed of training patterns. The structure of neural networks evolve to optimal structure and, at the same time, training patterns coevolve to feature patterns. This method prevent the system from the limitation of the performance by random design of neural network structure and inadequate selection of training patterns. In this time neural networks are trained by evolution strategies that are able to apply to the unsupervised learning. And in the coding of neural networks, we propose the method to maintain nonredundancy and character preservingness that are essential factor of genetic coding. We show the validity and the effectiveness of the proposed scheme by applying it to the visual servoing of RV-M2 robot manipulators.

• 전자공학회논문지
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• 제50권3호
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• pp.203-211
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• 2013

본 논문에서는 바닥작업용 서비스 로봇을 위한 두 팔 매니퓰레이터의 개발 및 제어에 관한 연구를 기술하였다. 6자유도의 매니퓰레이터를 설계하였으며, 그 중 5자유도 매니퓰레이터를 제작하였다. 제작된 매니퓰레이터의 순기구학과 역기구학을 해석하고 시뮬레이션을 수행하여 기구학을 검증하였다. 실제로 역기구학을 바탕으로 로봇 팔을 제작하여 제어하였다. 양팔의 동작 성능을 확인하기 위해 오른쪽 팔과 왼쪽 팔을 각각 따로 제어하여 서로 다른 경로를 추종하는 실험을 수행하였다. 실험결과를 통해 기구학 분석을 검증하였으며, 시스템의 동작 여부를 확인할 수 있었다.

• 제어로봇시스템학회논문지
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• 제18권6호
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• pp.579-583
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• 2012

The purpose of this paper is to suggest IDE (Incremental Displacement Estimation) algorithm for the previously proposed visually servoed paired structured light system. The system is composed of two sides facing with each other, each with one or two lasers with a 2-DOF manipulator, a camera, and a screen. The 6-DOF displacement between two sides can be estimated by calculating the positions of the projected laser beams and rotation angles of the manipulators. In the previous study, Newton-Raphson or EKF (Extended Kalman Filter) has been used as an estimation algorithm. Although the various experimental tests have validated the performance of the system and estimation algorithms, the computation time is relatively long since aforementioned algorithms are iterative methods. Therefore, in this paper, a non-iterative incremental displacement estimation algorithm which updates the previously estimated displacement with a difference of the previous and the current observed data is introduced. To verify the performance of the algorithm, experimental tests have been performed. The results show that the proposed non-iterative algorithm estimates the displacement with the same level of accuracy compared to the EKF with multiple iterations with significantly less computation time.