• 한국정보과학회논문지:소프트웨어및응용
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• 제30권11호
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• pp.1092-1101
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• 2003

대부분의 3차원 캐릭터 애니메이션에서는 모션 캡쳐 장비를 통해서 포착된 동작 데이타를 이용하여 다양한 지형상에서 캐릭터가 걷는 동작을 표현한다. 이러한 동작 포착 데이타는 실제 사람과 같이 움직이는 동작들을 자연스럽게 표현할 수 있으나, 만약 다양한 지형에 대한 움직이는 동작이 표현할 경우, 지형의 유형에 따라 모든 동작을 캡쳐하여야 하고, 얻어진 동작 데이타를 다른 유형의 캐릭터에 적용할 경우 동작 데이타를 다시 얻거나 기존 동작 데이타를 재편집해야 하는 어려움이 있다. 따라서 본 연구에서는 적은 매개변수들을 사용하여 평지면, 경사면, 계단면 그리고 굴곡면 등 다양한 지형에서의 적응적인 걷는 동작을 생성하기 위한 방법과 골반과 이동하는 다리의 움직임 제적을 산출하는 방법을 제안한다. 이 방법에서는 캐릭터의 신장이나 걷는 속도, 걸음폭 등의 매개변수들을 조절하여 다양한 걸음걸이를 생성할 수 있으며 역운동학(Inverse Kinematics) 개념을 적용하여 관절들의 위치나 각도를 산출하고 관절의 이동 궤적을 계산하기 위해 큐빅 스플라인 곡선을 활용한다.

• PNF and Movement
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• 제12권2호
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• pp.89-96
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• 2014

Purpose: The purpose of this study was to examine the influence of foot angles on plantar pressure and the center of pressure (COP) trajectory length during level walking. Methods: The study subjects were 30 female university students without orthopedic diseases in the foot. The foot angle was divided into three forms (out-toeing, normal, in-toeing). The subjects practiced each type of gait, and then performed each of level walking, three times, and their averages were calculated. A plantar pressure measurement instrument was used, and the maximum force was obtained by dividing the foot into nine regions covering the anterior medial-lateral, middle medial-lateral, and posterior medial-lateral. The COP trajectory length was statistically processed by obtaining medial-lateral, anterior-posterior, and entire travel distance. Results: During normal walking, the maximum force was significantly higher in the anterior lateral than in the other areas, and the COP trajectory length was significantly shorter in the front-back and entire travel distances (p<0.05). During stair climbing. Conclusion: Walking at abnormal foot angles does not cause appreciable problems in the short term as pressure is concentrated on a specific plantar part. However, it becomes the cause of deformed foot structures and can result in musculoskeletal disabilities in the long term. Therefore, a kinesiatrics-based intervention is required to maintain normal foot angles.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년 학술대회 논문집 정보 및 제어부문
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• pp.539-541
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• 2006

Biped locomotion is a popular research area in robotics due to the high adaptability of a walking robot in an unstructured environment. When attempting to automate the motion planning process for a biped walking robot, one of the main issues is assurance of dynamic stability of motion. This can be categorized into three general groups: body stability, body path stability, and gait stability. A zero moment point (ZMP), a point where the total forces and moments acting on the robot are zero, is usually employed as a basic component for dynamically stable motion. In this rarer, learning based neuro-fuzzy systems have been developed and applied to model ZMP trajectory of a biped walking robot. As a result, we can provide more improved insight into physical walking mechanisms.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1185-1188
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• 1996

In this paper we present a genetic approach for trajectory control algorithm of balancing weight for IWR biped walking robot. The biped walking robot, IWR that was made by Automatic Control Lab. of Inha University has a trunk which stabilizes its walking by generating compensation moment. Trunk is composed of a revolute and a prismatic joint which roles balancing weight. The motion of balancing weight is determined by the gait of legs and represented by two linear second order ordinary differential equations. The solution of this equation must satisfy some constraints simultaneously to have a physical meaning. Genetic algorithm search for this feasible motion of balancing weight under some constraints. Simulation results show that feasible motion of balancing weight can be obtained by genetic algorithm.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 하계학술대회 논문집 D
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• pp.2438-2440
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• 2004

This study is concerned with development of 3-Dimensional simulator of a biped robot that has a prismatic balancing weight or a revolute balancing weight. The dynamic stability equation of a biped robot which have a prismatic balancing weight is conditional linear but a walking robot's stability equation with a revolute balancing weight is nonlinear. To get a stable gait of a biped robot, stabilization equations with ZMP (Zero Moment Point) are modeled as non-homogeneous second order differential equations for each balancing weight type. A trajectory of balancing weight can be directly calculated with the FDM (Finite Difference Method) solution of the linearized differential equation. In this paper, the 3-Dimensional graphic simulator is programmed to get and calculate the desired ZMP and the actual ZMP. Walking of 4 steps was simulated and verified. This balancing system will be applied to a biped humanoid robot, which consist Begs and upper body, at future work.

• Journal of Electrical Engineering and Technology
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• 제11권3호
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• pp.751-758
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• 2016

The modifiable walking pattern generation (MWPG) algorithm can handle dynamic walking commands by changing the walking period, step length, and direction independently. When an infeasible command is given, the algorithm changes the command to a feasible one. After the feasibility of the navigational command is checked, it is translated into the desired center of mass (CM) state. To achieve the desired CM state, a reference CM trajectory is generated using predefined zero moment point (ZMP) functions. Based on the proposed algorithm, various complex walking patterns were generated, including backward and sideways walking. The effectiveness of the patterns was verified in dynamic simulations using the Webots simulator.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집A
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• pp.523-528
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• 2000

In this paper, the new type biped walking robot which is composed of the minimum number or links just for walking and its appropriate gaits are proposed. The proposed new gaits for this robot are four-crossing, crawling, standing and turning gait. In designing the biped robot we propose the Performance Index which means the needed torque per a moving distance and generate foot trajectories by $3^{rd}$ order spline Interpolation. Among those, numerically we find the optimal conditions which minimize the Performance Index. Dynamically stable walking of the biped robot is realized by satisfying the stability condition of ZMP(zero moment point), which is related to maintaining the ZMP within the region of the supporting foot during the s1n91e leg support phase. We determine the region of mass center from the stability condition of ZMP and plan references which track the mass conte. trajectory of constant velocity. Finally we implement the gaits statically tracking the planned trajectories using PD control method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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• pp.244-244
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• 2000

We proposed the above-knee prosthesis using rotary MR damper in which knee joint is semi-actively controlled by microprocessor. Dissipation torque in the knee joint can be controlled by the magnetic field which is induced by applying current to a solenoid, Tracking control of knee joint angle was tested by 3-DOF Leg simulator. The experimental results show that the proposed above-knee prosthesis system had good performance in swing phase tracking and repetitive controller in conjunction with a computed control law and PD control law, reduced RMS tracking error as the repetitions of tracking. Moreover, desired knee angle trajectory was generated based on the estimation of gait period with the gyro signal and the tracking control was performed.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1998년도 추계학술대회
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• pp.80-81
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• 1998

In this study, an experiments and numerical simulation of a three chamber pneumatic cylinder for an intelligent AK-knee prosthesis is performed. The cylinder has a variable orifice which can be controlled automatically through a microprocessor controller as needed while amputee gaits. In the experiment, the cylinder was driven by a cam whose trajectory of simulates the normal gait and axial forces of cylinder with different of orifice opening was measured. The numerical simulations was based on thermodynamic and fluid mechanical consideration. The experimental results and the numerical results were in good agreement.

• 한국산학기술학회논문지
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• 제11권10호
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• pp.3658-3665
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• 2010

최근 고령화 사회로의 진입 및 장애 인구의 증가로 인해, 인간의 복지를 위한 자동화 시스템에 대한 수요가 늘고 있다. 특히 재활 자동화와 관련한 로봇 시스템은 환자 본인 및 치료 보조자에 대한 수고를 덜어주면서도 기존의 전통적인 재활효과에 상응하는 성과를 얻을 수 있을 것으로 기대되고 있다. 본 연구는 하지 근력이 약화된 사용자들의 신체 자중을 보상해줌과 동시에 정상인과 같은 패턴의 보행 훈련을 수행할 수 있는 모바일형 보행 재활 시스템을 제안하고자 한다. 특히, 자중보상 시스템은 신체의 자세 변화 특징을 반영하여, 기구학적인 분석을 통해 구현하였으며 보행 가이드를 위한 제어 알고리즘과 더불어 메인 컨트롤 시스템이 내장된 모바일 플랫폼에 통합 적용되었다. 이러한 모바일 플랫폼은 사용자의 보행 속도의지를 반영하는 UCS(User Command System)와 플랫폼 자체에 내장된 자율주행 알고리즘의 병합되어 운용되도록 고안되었으며, 본 논문에서는 보행 훈련시의 BWS(Body Weight Support)의 효과에 대한 검증에 집중하고자 한다. 이를 위해 인체의 근전도 신호를 측정할 수 있는 EMG(Electromyography) 센서를 활용하여, BWS 및 모바일로봇을 활용한 자중 보상 시의 피험자의 하지 근력 패턴을 측정 및 분석하여, 정상 보행자와의 차이점을 비교함으로서 본 연구의 타당성을 검증하였다.