• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2003년도 ICCAS
• /
• pp.1629-1632
• /
• 2003

A technique is presented for generating a compound human motion from its primitive motions obtained by a motion capture system. Some human fundamental motions are modeled in a 3-D way and registered as primitive motions. Because the factorization method is used for the motion capture, calibration of video cameras and connection of the motion in the direction of time is both unnecessary. Employing these motions, various compound human motions are generated by connecting the motions after having applied rotation and parallel transformation to them. Linear interpolation is done at the discontinuous boundary between primitive motions and smooth connection is achieved. Experimental results show satisfactory performance of the proposed technique. The technique may contribute to producing various complicated human motions without much effort using a strict motion capture system.

• 한국콘텐츠학회논문지
• /
• 제14권9호
• /
• pp.1-13
• /
• 2014

가상 세계의 에이전트의 설계를 위해서 물리적 사실감뿐만 아니라 동적으로 변하는 상황에 대응하는 에이전트의 다양한 물리적 행동들의 구현이 필수적이다. 본 연구는 다양한 행동을 구현하기 위한 기본 동작들을 재활용한 복합적 행동 및 에이전트가 즉시 주위의 환경에 반응할 수 있는 기법을 구현한다. 또한 관절에 대한 에이전트의 신체 구조를 설계하고 기본 동작 또는 복합 동작을 실시간으로 표현한다. 이 기법을 구현하기 위해서, 기본적인 관절 회전을 위한 애니메이션 함수와 기본 동작으로 이루어진 전체적 동작을 구성하는 기능을 구현한다. 이러한 동작들은 에이전트의 목적을 달성하는 계획에 포함될 수 있다. 즉, 재활용된 기본 동작을 이용하여 다양한 행동을 쉽게 생성하는 기법을 개발한다. 본 연구는 '걸으면서 먹다'와 같은 병렬 행동을 구현할 때 뚜렷한 장점을 가진다. 이는 두 개 이상의 행동들은 우선순위에 따라 자연스럽게 병렬 행동으로 조합된다. 이를 증명하기 위해 몇 개의 복합 행동 및 병렬 행동을 구현한다.

• 대한기계학회논문집A
• /
• 제29권4호
• /
• pp.540-554
• /
• 2005

This paper presents a motion planning and control method for the dexterous manipulation with a robotic hand. For a given trajectory of an object, a simulation system calculates the necessary joint displacements and contact forces at the fingertip surfaces. These joint displacements and contact forces are the reference inputs to the control loops of the robotic fingers. A task is decomposed into a set of primitive motions, and each primitive motion is executed using the planned output of the simulation system as the reference. Force sensors and dynamic tactile sensors are used to adapt to errors and uncertainties encountered during manipulation. Several experimental results are presented.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.315-316
• /
• 2007

This paper presents a new methodology to improve movement database for a humanoid robot. The database is initially full of human motions so that the kinetics characteristics of human movement are immanent in it. then, the database is updated to the pseudo-optimal motions for the humanoid robot to perform more natural motions, which contain the kinetics characteristics of robot. for this, we use the evolutionary algorithm. the methodology consists of two processes : (1) the offline imitation learning of human movement and (2) the online generation of natural motion. The offline process improve the initial human motion database using the evolutionary algorithm and inverse dynamics-based optimization. The optimization procedure generate new motions using the movement primitive database, minimizing the joint torque. This learning process produces a new database that can endow the humanoid robot with natural motions, which requires minimal torques. In online process, using the linear combination of the motion primitive in this updated database, the humanoid robot can generate the natural motions in real time. The proposed framework gives a systematic methodology for a humanoid robot to learn natural motions from human motions considering dynamics of the robot. The experiment of catching a ball thrown by a man is performed to show the feasibility of the proposed framework.

• International Journal of Contents
• /
• 제15권4호
• /
• pp.16-26
• /
• 2019

The efficient implementation of various physical actions of agents to respond to dynamically changing situations is essential for the simulation of realistic agents and activities in a cyber world. To achieve a maximum diversity of actions and immediate responsiveness to abrupt changes in situations, we have developed an animation technique in which complex actions are recursively constructed by reusing a set of primitive motions, and agents are designed to react in real-time to abrupt ambient changes by computationally satisfying kinematic constraints on body parts with respect to their goals. Our reusing scheme is extended to visualize the procedure of realistic intricate situations involving many concurring events. Our approach based on motion reuse and recursive assembly has clear advantages in motion variability and action diversity with respect to authoring scalability and motion responsiveness compared to conventional monolithic (static) animation techniques. This diversity also serves to accommodate the characteristic unpredictability of events concurring in a situation due to inherent non-determinism of associated conditions. To demonstrate the viability of our approach, we implement several composite and parallel actions in a dynamically changing example situation involving events that were originally independent until coincidentally inter-coupled therein.

• 제어로봇시스템학회논문지
• /
• 제14권10호
• /
• pp.1038-1046
• /
• 2008

This paper presents a framework to generate human-like movements of a humanoid in real time using the movement primitive database of a human. The framework consists of two processes: 1) the offline motion imitation learning based on an Evolutionary Algorithm and 2) the online motion generation of a humanoid using the database updated bγ the motion imitation teaming. For the offline process, the initial database contains the kinetic characteristics of a human, since it is full of human's captured motions. The database then develops through the proposed framework of motion teaming based on an Evolutionary Algorithm, having the kinetic characteristics of a humanoid in aspect of minimal torque or joint jerk. The humanoid generates human-like movements far a given purpose in real time by linearly interpolating the primitive motions in the developed database. The movement of catching a ball was examined in simulation.

• 한국멀티미디어학회논문지
• /
• 제4권3호
• /
• pp.238-246
• /
• 2001

복지형 정보단말 장치로 청각장애인과 건청인사이의 커뮤니케이션을 지원하기 위한 수화 생성시스템이 개발되었다. 이 시스템에서는 신체의 각 부위의 움직임을 주목한Motion-Primitives에 기초로 하여 컴퓨터그래픽(CG) 애니메이션으로 수화 단어 동작을 생성하고 있다. 기존의 수화 생성시스템은 수화 단어를 생성할 때 손 모양이나 손과 어깨의 움직임을 제어하기가 어려워 수화 단어를 생성하는데 많은 시간이 소요되었다. 또한 수화 통역을 위해서는 수화단어가 5000단어 이상이 필요하기 때문에 수화단어 데이터 베이스를 구축하는 것도 큰 문제로 대두되고 있다. 따라서, 본 논문에서는 종래의 시스템보다 수화단어 구축에 있어서 다양한 움직임의 경로를 유연하게 만들수 있는 Motion-Primitives에 의한 새로운 시스템을 제안한다. 이 제안한 시스템을 적용하여 실제로 청각장애인을 대상으로 수화단어 100단어에 대하여 평가실험을 행한 결과 종래의 시스템으로 평균 76%의 인식 율을 얻을 수 있었던 것에 비하여 새롭게 제안한 시스템은 82%의 양호한 인식 율을 얻을 수 있었다.

• 한국CDE학회논문집
• /
• 제2권1호
• /
• pp.60-67
• /
• 1997

CAD systems offer a variety of techniques for designing and rendering models of static 3D objects and even of mechanisms, but relatively few tools exist for interactively specifying arbitrary movements of rigid bodies through space. Such tools are essential, not only for artistic animation, but also, for planning and demonstrating assembly and disassembly procedure of manufactured products. A rigid body motion is a continuous mapping from the time domain to a set of positions. To relieve the designers from the burden of specifying this mapping in abstract mathematical terms, combinations of simple rigid motion primitives, such as linear translations or constant axis rotations, are often used. These simple motions are planar and thus ill-suited for approximating arbitrary motions in 3D-space. Instead, we propose the screw motion primitive, a special combination of linear translations and constant axis rotations, which has a simple geometric representation that can be automatically and unambiguously computed from the starting and ending positions of the moving body. Although, any two positions may be interpolated by an infinity of motions, we chose the screw motion for its relative generality and its computational advantages. The paper covers original algorithms for computing the screw motions from interpolated positions and envelopes of swept regions to predict collisions.

• 로봇학회논문지
• /
• 제8권1호
• /
• pp.1-7
• /
• 2013

Body gesture Recognition has been one of the interested research field for Human-Robot Interaction(HRI). Most of the conventional body gesture recognition algorithms used Hidden Markov Model(HMM) for modeling gestures which have spatio-temporal variabilities. However, HMM-based algorithms have difficulties excluding meaningless gestures. Besides, it is necessary for conventional body gesture recognition algorithms to perform gesture segmentation first, then sends the extracted gesture to the HMM for gesture recognition. This separated system causes time delay between two continuing gestures to be recognized, and it makes the system inappropriate for continuous gesture recognition. To overcome these two limitations, this paper suggests primitive body model encoding, which performs spatio/temporal quantization of motions from human body model and encodes them into predefined primitive codes for each link of a body model, and Selective/Asynchronous Input-Parallel State machine(SAI-PSM) for multiple-simultaneous gesture recognition. The experimental results showed that the proposed gesture recognition system using primitive body model encoding and SAI-PSM can exclude meaningless gestures well from the continuous body model data, while performing multiple-simultaneous gesture recognition without losing recognition rates compared to the previous HMM-based work.

• 한국콘텐츠학회논문지
• /
• 제11권7호
• /
• pp.9-20
• /
• 2011

본 논문은 가상세계속의 가상인간의 다양한 행동들을 제한된 개수의 기본행동들로써 구현하고자 한다. 먼저 객체들의 속성과 행동 등을 통합적으로 나타내주는 지식베이스인 온톨로지를 사용하여 다양한 행동들을 행동계층구조로 조직하고 그 속에서 행동들은 세부 행동들로 구체화한다. 가상인간의 기본행동은 기초 동작들의 조합으로 만들어지고 기본행동들을 최대한 재사용함으로써 다양한 행동들을 효과적으로 구현할 수 있게 설계한다. 이 때 기본행동들을 정밀성이나 사실성보다 간소함과 다양성에 초점을 맞추어 구현하고자 한다. 이를 바탕으로 가상 에이전트들의 특성을 파악하고 특성에 따라 에이전트가 고유의 패턴을 가지고 동작을 생성하는 방법을 개발한다. 또한 가상의 에이전트가 주변의 정성적 변화에 적응하여 동작을 변화하는 방법을 제시한다. 이렇게 제시된 방법들을 인간의 실제 움직임들 즉, 걷기, 달리기, 던지기 등의 동작에 적용해 실현가능성을 검증한다.