• 한국정밀공학회지
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• 제34권2호
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• pp.115-123
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• 2017

This paper presents the design and the control performance of a novel dynamic compliant-arm support with parallel elastic actuators that was developed to assist with the daily living activities of those whose arms are compromised by muscular disease or the aging process. The parallel elastic-arm support consists of a compliant mechanism with combined passive and active components for human interaction and to reach the user's desired positions. The achievement of these tasks requires impedance control, which can change the virtual stiffness, damping coefficients, and equilibrium points of the system; however, the desired-position tracking by the impedance control is limited when the end-effector weight varies according to the equipping of diverse objects. A prompt algorithm regarding weight calibration and friction compensation is adopted to overcome this problem. A result comparison shows that, by accurately assessing the desired workspace, the proposed algorithm is more effective for the accomplishment of the desired activities.

• 한국자동차공학회논문집
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• 제13권1호
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• pp.119-125
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• 2005

The current automotive is seeking the improvement of performance, the prevention of environmental pollution and the saving of energy resources according to miniaturization and lightweight of the components. And the variance analysis on the basis of structure analysis and DOE is applied to the lower control am. We have proposed a statistical design model to evaluate the effect of structural modification by performing the practical multi-objective optimization considering weight, stress and fatigue lift. The lower control arm is performed the fatigue analysis using the load history of real road test. The design model is determined using the optimization of acquired load history with the fatigue characteristic. The characteristic function is made use of the optimization according to fatigue characteristics to consider constrained function in the optimization of DOE. The structure optimization of a lower control arm according to fatigue characteristics is performed. And the optimized design variable is D=47 m, T=36mm, W=12 mm. In the real engineering problem of considering many objective functions, the multi-objective optimization process using the mathematical programming and the characteristic function is derived an useful design solution.

• 한국지능시스템학회논문지
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• 제21권5호
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• pp.595-601
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• 2011

본 논문에서는 영상 정보를 이용하여 로보커 팔위의 역진자의 밸런싱 제어를 한다. 로봇 팔위에 놓인 역진자의 각도는 카메라로 검출하고 검출된 각도 값은 제어기로 귀환되어 오차를 생성한다. 따라서 전체 제어루프는 폐회로 루프를 형성한다. 제어 성능을 높이기 위해 기존 선형제어기에 신경망 제어기를 더하였다. RBF 네트워크의 학습 알고리즘은 FPGA에 설계된 부동소수점 연산이 가능한 디지털 제어기에 의해 수행된다. 실험을 통하여 전체 시스템 성능을 검증하였다.

• 제어로봇시스템학회논문지
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• 제6권8호
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• pp.682-688
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• 2000

To improve the performance of a flexible robot arm one of the important things is the vibration displacement measurement of a flexible arm. Many types of sensors have been used to measure it, The most popular has been strain gauges which measures the deflection of the beam,. Photo sensors have also been for detecting beam displacement and accelerometers are often used to measure the beam vibration. But the vibration displacement can be obtained indirectly from these sensors. In this article a vision sensor is used as a displacement sensor to measure the vibration displacement of a flexible robot arm. Several schemes are proposed to reduce the image processing time and increase its accuracy. From the experimental results it is seen that the vision sensor can be an alternative sensor for measuring the vibration displacement and has a potential for on-line tip position control of flexible robot systems.

• Journal of Korean Biological Nursing Science
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• 제14권4호
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• pp.300-307
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• 2012

Purpose: The purpose of this research was to develop and prove the effectiveness of structured arm exercise, which was used to reduce Arteriovenous Fistula (AVF) and Arteriovenous graft (AVG) stricture of hemodialysis patients. Methods: Quasi-experimental research design with non-equivalent control group was applied. 26 Subjects were participated in this study. 12 of hemodialysis patients who do not have a normal range of Static Intra Access Pressure Vein (SIAPV) score in the last three months were assigned to the experimental group and 14 patients who have a normal range of SIAPV score in the last three months to the control group. To analyze the collecting data after structured arm exercise, non parametric method with the repeated measures ANOVA by the Friedman test and Wilcoxon Signed Ranks Test for post-hoc test was performed. Results: Unlike the experimental group after three months, the control group's SIAPV data went over the normal range. The experimental AVF group showed a difference in data after month 2 and month 3. - In AVG group, there were clear differences in each month of the test. Conclusion: This study proved that structured arm exercise therapy could be a simple and effective intervention. It is suggested to be actively utilized for hemodialysis patients.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.1322-1325
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• 1997

A new feedback control law design techniqed usign of-off thrusters for the rotational maneuver of a flexible arm is discussed in this study. a two state on-off thruster actuator is taken as a primary actuation device for theis study. The on-off thruster operation is emulated in conjunction with the conventioal minimum-time trackig control law. The actuator input region is divided into two separate parts ; one is constant input and the other is time varying tegion. the new control law has potential applicatioin for the relatively low frequency structure such as large flexible space structure being currently used in various space echnology areas.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집(한일합동학술편); 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.905-908
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• 1987

A human operator has the ability to control a complicated system such as a gantry crane, an aircraft and a remote manipulator after enough training and learning. In this article, we attempt the positioning experiment of a flexible arm by a human operator. Flexible arm has nonlinearlity and infinite-degrees of freedom in general; thus it is difficult to obtain a control input. The operator interprets a given task and finds the procedure of operations. He devises an effective way of achieving the goal on the basis of his experience and knowledge about the task.

• 제어로봇시스템학회논문지
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• 제3권5호
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• pp.461-468
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• 1997

A real-time collision-free trajectory control method for dual arm robot system is proposed. The proposed method is composed of two stages; one is to calculate the minimum distance between two robot arms and the other is to control the trajectories of the robots to ensure collision-free motions. The calculation of minimum distance between two robots is, also, composed of two steps. To reduce the calculation time, we, first, apply a simple modeling technique to the robots arms and determine the interested part of the robot arms. Next, we apply more precise modeling techniques for the part to calculate the minimum distance. Simulation results show that the whole algorithm runs within 0.05 second using Pentium 100MHz PC.

• 한국소음진동공학회논문집
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• 제12권8호
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• pp.609-615
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• 2002

본 논문에서는 단순하고 효율적인 학습제어 로직을 운동기구용 로봇팔 시스템에 적용하였다. 일반적으로 운동시에 운동기구에 적용되는 힘은 사용자마다 다르고 같은 사용자라 하더라도 운동시마다 다를 것이다. 이미 사용자의 신체조건에 따라 입력된 최적의 힘과 실제 가해지는 힘 사이의 오차를 보상하는데 본 논문에서는 학습제어를 적용하여 가해지는 힘의 종류(시변 또는 시불변함수)와 상관없이 빠르게 오차를 제거하고 원하는 운동을 추종함을 시뮬레이션을 통하여 확인할 수 있었다.

• 전자공학회논문지B
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• 제33B권7호
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• pp.40-50
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• 1996

An unified compliant control algorithm to regulate the force by dual arms is proposed, where tow arms are treated as one arm in a kinematic viewpoint. The force error calculated form the information of two force/torque sensors attached to the end of each arm is transferred to minimum actuator coordinates, and then is distributed to total system actuator coordinates. The position adjustment at the total actuator coordinates is computed based on the effective computed based on the effective compliance matrix with respect to total actuator coordinates, which is obtained by coordinate transformation between the task coordinates and the total actuator coordinates. An experiment is carried out for dual arms with asymmetric kinematic structure to control an interaction force between manipulators and the environment. The performances of the proposed control algorithm are experimentally compared to those of dual arms employing master/slave scheme. The proposed compliant control algorithm not only ouperforms other algorithms, but also can be treated as an unified approach n the sense that it can be applied to arbitrary dual arm systems with general kinematic structures.