• 제어로봇시스템학회논문지
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• 제19권12호
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• pp.1160-1166
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• 2013

This paper presents feedforward controllers to improve the control performance of the motion and grasping force of a surgical instrument used in an MIS (Minimally Invasive Surgery) robot. The surgical instrument has a long distance between the drive motors and its active joints. Therefore, the gripper on the instrument is controlled by a cable drive mechanism, which generates a coupled motion between the wrist joint and the grip direction. In order to solve the problem, this paper analyzes the pulley composition of the surgical instrument and proposes feedforward controllers to eliminate the coupled motion. Furthermore, feedforward controllers to regulate the grasping force are proposed to deal with another coupling problem between the grasping force of the instrument and the motion of the instrument joints. The experimental results demonstrate the improved control performance of the motion and grasping force of the instrument.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.24.2-27
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• 1996

This paper is a study on the fuzzy force control of a miniature gripper driven by piezoelectric bimorph actuator. The system is composed of two flexible cantilevers, a stepping motor, a laser displacement transducer and two semiconductor force sensors attached to the beams. Obtained results show that the present artificial finger system works well as a miniature gripper, which produces approximately 0.06N force in the maximum. Further, the fuzzy position/force control algorithm is applied to the soft-handing gripper for stable grasping of a object. It revealed that the fuzzy rule-based controller be efficient controller for the stable drive of the flexible miniature gripper. It also showed that two semiconductor strain gauges located in the flexible beam play an important roles for force control, position control and vibration suppression control.

• 대한인간공학회:학술대회논문집
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• 대한인간공학회 1997년도 추계학술대회논문집
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• pp.359-365
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• 1997

When grasping a movable object or making an object move, humans feel kinesthetic sense. Kinesthetic sense is the human sense that the human feels in response to the motion acted on the human. The objecive of the paper is tranforming the kinesthetic sense to quantitized data that is useful from the viewpoint of engineering. To provide various motion patterns, 2-dimensional motion generator was built using 2-axis linear motors. Active stiffness and active damping were implemented by means of current control and force feedback techniques. Based on Taguchi method, the most dominant factors to affect kinesthetic sense were investigated. Also, some functions adequate to quantize the kinesthetic sense were found.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.83.1-83
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• 2001

This paper presents a three-fingered robot hand, called the KIST hand, Which have one active joint and one passive joint. The thumb is fixed on the palm, and the index and the middle take lateral motions symmetrically. A mechanical clutch and an embedded force sensor, attached on the distal link of the fingers, enable the KIST hand to perform human-like functions. A result of experiment shows reliable grasping performance of the hand which maintain stable grasp under disturbances.

• Journal of Information Processing Systems
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• 제18권5호
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• pp.688-700
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• 2022

A composite bionic soft gripper integrated with electromagnets and magneto-active elastomers is designed by combining the structure of the human hand and the snake's behavior of enhancing friction by actively adjusting the scales. A silicon-based polymer containing magnetized hard magnetic particles is proposed as a soft finger, and it can be reversibly bent by adjusting the magnetic field. Experiments show that the length, width, and height of rectangular soft fingers and the volume ratio of neodymium-iron-boron have different effects on bending angle. The flexible fingers with 20 vol% are the most efficient, which can bend to 90° when the magnetic field is 22 mT. The flexible gripper with four fingers can pick up 10.51 g of objects at the magnetic field of 105 mT. In addition, this composite bionic soft gripper has excellent magnetron performance, and it can change surface like snakes and operate like human hands. This research may help develop soft devices for magnetic field control and try to provide new solutions for soft grasping.

• Journal of Electrical Engineering and Technology
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• 제10권4호
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• pp.1408-1414
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• 2015

The renewable energies such as photovoltaic power, wind power and biomass have grown to a greater extent as decarbonization techniques. The renewable energies are interconnected to power systems (or electrical grids) in order to increase benefits from economies of scale, and the extra attention is focused on the Grid Code. A grid code defines technical parameters that power plants must meet to ensure functions of power systems, and the grid code determined by considering power system characteristics is various across the country. Some TSO (Transmission System Operator) and ISO (Independent System Operator) have issued grid code for wind power and the special requirements for offshore wind farm. The main purpose of the above grid code is that wind farm in power systems has to act as the existing power plants. Therefore wind farm developer and wind turbine manufacturer have great difficulty in grasping and meeting grid code requirements. This paper presents the basic understanding for grid codes of developed countries in the wind power and trends of those technical requirements. Moreover, in grid code viewpoint, the active power control of wind power is also discussed in details.

• 한국산업융합학회 논문집
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• 제18권4호
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• pp.216-223
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• 2015

Recently Manipulation capability is important for a robot. Interaction between a robot hand and objects can be properly controlled only is suitable sensors are available. Recently the tendency is to create robot hands more compact and high integrated sensors system, in order to increase the grasping capability and in order to reduce cabling through the finger, the palm and the arm. As a matter of fact, miniaturization and cabling harness represents a significant limitation to the design of small sized embedded sensor. Ongoing work is focusing on a flexible manipulation system, which consists of a dual flexible multi-fingered hand-arm system, and a dual active vision system.

• 한국환경과학회지
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• 제19권8호
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• pp.1067-1076
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• 2010

How would environmental education be implemented for effectiveness today? Deep reflection on the way of teaching environment in classes to achieve effectiveness is required. If there exist differences in students' environmental perception depending on environment class pattern, its most effective way should be looked for. In environmental education, inducing the students to have advisable attitude voluntary about environment is more important than teaching them environmental knowledge. From such view, students' active participation is necessary for successful environmental classes. Students need to be set to share their principle, values, attitude about environment problems at environmental class through presentation which is important factor to make them have advisable environmental attitude. Therefore, environmental class need to be carried out student-led way. For that, a class model need to be designed which will be helpful for the students to arrange and elaborate their emitting thought about environment problems through disclosing their thoughts to share them with fellow students which will end up in their advisable environmental attitude. This study aimed to find out the effectiveness of environmental collage making class contributive to offering various environmental perception to students and grasping others' thinking about environment. Fifty-eight 10th graders at U Science High School in Ulsan metropolitan city were selected for the study that carried out from 2010 April to June by choosing total 10 environmental themes divided into environmental collage making class applied to the 30 test group students, and general environmental class applied to 28 control group students. Following are the study results. First, in students' environmental sensitivity, the students in the environmental collage making class appeared to be higher compared with them in general environmental class. Second, in students' intentional environment action, the students in the environmental collage making class appeared to be higher compared with them in general environmental class. Third, in students' satisfaction with environmental class, the students in the environmental collage making class appeared to be higher compared with them in general environmental class.

• 한국재난정보학회 논문집
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• 제18권4호
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• pp.687-698
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• 2022

연구목적: 본 연구는 빅데이터 플랫폼 '혜안'을 사용하여 2015년에서 2020년 사이의 산사태와 사방댐에 대한 언론 및 대중의 인식을 파악하고 방재 분야에서 '혜안'의 활용성을 확인하고자 수행되었다. 연구방법:빅데이터 플랫폼 '혜안'의 키워드 검색을 사용하여 2015~2020년의 '산사태'와 '사방댐'에 대한 검색 총량 및 시기에 따른 매체별 검색어 출현 횟수, 그리고 긍·부정 추이를 확인하였다. 연구결과:산사태에 비해 사방댐에 대한 인식이 현저하게 부족하며, 사방댐에 대한 언론보도와 트위터 및 블로그에서 나타나는 대중의 인식 수준 사이에 현저한 괴리가 나타난다. 산사태의 실제 발생 시기에 따라 극명하게 관심이 나타나는 '산사태'와 달리 '사방댐'에 대한 자료는 산사태의 실제 발생 시기와 시기적 연관성이 낮다. 사방댐에 대한 긍정적인 인식이 유추되지만 '혜안'으로는 재난 방지책에 대한 정확한 통계적 긍·부정 인식 확인이 어렵다. 결론: 전문가들이 사방사업에 대해 긍정적으로 인식하는 것에 비해 산사태에 대한 효과적인 방지책으로서의 사방댐에 대한 대중인식은 매우 저조하므로 사방사업에 대한 적극적인 홍보가 우선적으로 이루어져야 할 것이다. 추후 다양한 SNS 플랫폼에 대해 추가적인 빅데이터 조사와 함께 방재사업의 직접적 영향권에 있는 사람들을 대상으로 주기적인 현장 설문조사가 동반되어야 할 것이다. '혜안'을 사용한 방재 분야의 효과적인 인식 파악에는 한계가 있으므로 이를 활용한 지자체/정부적 정책 수립에는 신중을 기해야할 것이다.