• 로봇학회논문지
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• 제12권2호
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• pp.206-216
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• 2017

This paper proposes a method to simultaneously estimate two degrees of freedom in wrist forces (extension - flexion, adduction - abduction) and one degree of freedom in grasping forces using Electromyography (EMG) signals of the forearms. To correlate the EMG signals with the forces, we applied a multi - layer perceptron(MLP), which is a machine learning method, and used the characteristics of the muscles constituting the forearm to generate learning data. Through the experiments, the similarity between the MLP target value and the estimated value was investigated by applying the coefficient of determination ($R^2$) and root mean square error (RMSE) to evaluate the performance of the proposed method. As a result, the $R^2$ values with respect to the wrist flexion-extension, adduction - abduction and grasping forces were 0.79, 0.73 and 0.78 and RMSE were 0.12, 0.17, 0.13 respectively.

• 재활복지공학회논문지
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• 제2권1호
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• pp.45-49
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• 2009

본 논문에서는 상지마비 환자의 재활훈련용 로봇의 인터페이스에 사용할 수 있는 데이터글로브를 제안한다. 데이터글로브는 7개의 유연한 각도 센서를 적용하여 손가락과 손목의 굽힘 각도를 측정할 수 있다. 개발된 데이터글로브의 성능은 3D 그래픽을 이용한 시각화로서 확인하였다. 실험결과로부터 개발한 데이터글로브는 손의 움직임을 측정하고, 인터페이스로 사용할 수 있음을 보인다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 하계종합학술대회 논문집(5)
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• pp.39-42
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• 2000

In this paper we design the robust impedance controller of the robot manipulator with time delay. The designed controller considers time delay in the position loop and stabilizes the closed-loop system. The performance of a controller can be easily degraded by external disturbances. To improve the performance when external disturbances exist, we use the disturbance observer to handle the disturbances in the velocity loop and provide robustness to the control system. To show the validity of the designed controller, several experiments are performed for the 5-DOF robot manipulator equipped with the wrist force/torque sensor system.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 ITC-CSCC -2
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• pp.604-607
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• 2000

In this paper we design the robust impedance controller of the robot manipulator with time delay. The designed controller considers time delay in the position loop and stabilizes the closed-loop system. The performance of a controller can be easily degraded by external disturbances. To improve the performance when external disturbances exist, we use the disturbance observer to handle the disturbances in the velocity loop and provide robustness to the control system. To show the validity of the designed controller, several experiments are performed for the 5-DOF robot manipulator equipped with the wrist force/torque sensor system.

• Transactions on Control, Automation and Systems Engineering
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• 제4권1호
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• pp.49-55
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• 2002

A decrease in the birthrate and aging are progressing in Japan and several countries. In that society, it is important that physically weak persons such as elderly persons are able to take care of themselves. We have been developing exoskeletal robots for human (especially for physically weak persons) motion support. In this study, the controller controls the angular position and impedance of the exoskeltal robot system using multiple fuzzy-neuro controllers based on biological signals that reflect the human subject's intention. Skin surface electromyogram (EMG) signals and the generated wrist force by the human subject during the elbow motion have been used as input information of the controller. Since the activation level of working muscles tends to vary in accordance with the flexion angle of elbow, multiple fuzzy-neuro controllers are applied in the proposed method. The multiple fuzzy-neuro controllers are moderately switched in accordance with the elbow flexion angle. Because of the adaptation ability of the fuzzy-neuro controllers, the exoskeletal robot is flexible enough to deal with biological signal such as EMG. The experimental results show the effectiveness of the proposed controller.

• 제어로봇시스템학회논문지
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• 제7권6호
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• pp.532-539
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• 2001

In robot teleoperation, much research has been carried out to control the slave robot from remote site. One of the essential devices for robot teleoperation is the masterarm, which is a path command generating device worn on human arm. In this paper, a new masterarm based on human kinematics is proposed. Its controller is based on the distributed controller architecture composed of two controller parts: a host controller and a set of satellite controllers. Each satellite controller measures the corresponding joint angle, while the host controller performs forward and inverse kinematics calculation. This distributed controller architecture can make the data updating faster, which allows to implement real-time implementation. The host controller and the satellited controllers are networked via three-wire daisy-chained SPI(Serial Peripheral Interface) protocol, so this architecture makes the electrical wiring very simple, and enhances maintenance. Analytical method for finding three additional unknown joint angles is derived using only three measured angles for each shoulder and wrist, which makes th hardware implementation very simple by minimizing the required number of satellite controllers. Finally, the simulation and experiment results are given to demonstrate the usefulness and performance of the proposed masterarm.

• 전자공학회논문지CI
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• 제40권2호
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• pp.9-16
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• 2003

본 논문에서는 개선된 SOFM(Self Organizing Feature Map)방식을 이용한 근전도 패턴인식으로 가상 로봇 팔을 제어하는 방식을 제안한다. 개선된 SOFM 방식은 근전도 신호의 전처리기를 사용하는 대신에 근전도 신호 자체를 SOFM에 입력으로 사용하고, 퍼지논리시스템을 이용하여 SOFM의 이웃반경과 학습율을 자동 조절하는 간단한 방식으로 입력 패턴을 더욱 빠르고 신뢰성있게 분류한다. 개선된 방식의 성능을 확인하기 위하여 어깨, 손목, 팔꿈치의 여섯 가지 동작의 근전도 패턴인식을 실험한 결과 기존의 일반적인 SOFM방식보다 제안한 SOFM방식의 인식율이 21.7% 향상되고, 평균학습 수도 절반이하로 감소되었으며, 인식한 근전도 신호를 이용하여 컴퓨터 상의 가상 로봇 팔을 정확하게 제어하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.244-248
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• 1987

The force/torque sensor for robot is developed. The compliance algorithm for peg-in-hole insertion task using the forec/troque sensor is developed. The system consists of an IBM PC, robot, force/torque sensor, strain meter, A/D board, and interface board. The IBM PC functions as a main processor and the robot controller as a slave processor. The sensor is constructed to measure $T_x$, $T_y$, $F_z$ which are necessary to precisely execute a peg-in-hole insertion task by SCARA type assembly robot. The outputs of sensor are analyzed. On the basis of the analysis, compliance algorithm for peg-in-hole insertion task is developed. Some comments concerning the development of wrist force/torque sensor and compliance algorithm are given.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1991년도 추계학술대회 논문집
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• pp.139-145
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• 1991

본 논문에서는 chamfer가 없는 경우에도 조립이 가능한 로봇 조립용 손목기구를 개발하였다. 손목기구에서는 chamfer있는 경우에 우수란 적응능력을 가지는 RCC(Remote Center Compliance) 구조가 이용되었으며 위치측정용 sensor와 공압 actuator를 이용하여 조립시 생기는 RCC 구조의 변형을 측정하여 이로부터 능동적으로 오차를 교정하도록 하였다. sensor signal로부터 적절한 오차교정방향을 찾아내는 algorithm 으로는 신경회로망을 이용하였으며 이 결과 손목기구의 비선형성에도 잘 적응함을 볼 수 있었다. 제작된 로봇 조립용 손목을 이용하여 chamferless part의 조립을 실험한 결과 clearance ratio가 0.02인 경우 eccentricity가 2mm 까지 오차교정이 가능함을 볼 수 있었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1990년도 한국자동제어학술회의논문집(국제학술편); KOEX, Seoul; 26-27 Oct. 1990
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• pp.974-979
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• 1990

The system discussed in this paper is an integrated stand-alone system with the full functional capabilities required of a telerobot system. It is complete with a force-reflecting 6-DOF hand controller, driving a PUMA 560 or 762 robot, with an integrated force-torque sensing wrist sensor and servo-driven parallel jaw gripper. A mix of custom and standard electronics, distributed computers and microprocessors, with embedded and downloadable software, have been integrated into the system, giving rise to a powerful and flexible teleautonomous control system.