• 제목/요약/키워드: Motion Adaptation

검색결과 107건 처리시간 0.03초

누설요소와 인간 시각 시스템을 이용한 HDTV 영상 압축 알고리듬 (HDTV Image Compression Algorithm Using Leak Factor and Human Visual System)

  • 김용하;최진수;이광천;하영호
    • 한국통신학회논문지
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    • 제19권5호
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    • pp.822-832
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    • 1994
  • DSC-HDTV 시스템은 영상에 존재하는 공간, 시간, 진폭의 중복성을 제거하기위하여 변환 부호화, 움직임 보상 예측 부호화, 적응 양자화를 이용한다. 본 논문에서는 장면 변화와 전송 잡음으로부터 신속히 화질을 복원하는데 이용하는 누설요소의 적용 방법과 인간 시각 시스템을 이용한 인식하중치를 구하여 적응 양자화하는 방법을 제안한다. 인식하중치는 대비 민감도, 시공간 매스킹과 주파수 민감도에 따라 구한다. 적응 양자화는 인식하중치와 버퍼이력상태로부터 얻은 전체 왜곡 레벨을 이용하고 그에 따른 잉여 비트량은 다음 프레임의 화질 개선에 이용된다. 장면이 변할 경우 복원된 영상은 큰 양자화 오차를 포함하기 때문에 움직 보상 예측 부호화에서 구한 변위프레임 차신호가 큰 값이 되어 비트량이 증가하고 버퍼의 상태가 불안정하게 된다. 그러므로 본 논문에서는 누설요소를 장면이 변할 경우 0으로 하고 그이후의 프레임에서의 15/16으로 고정하여 전체왜곡레벨을 표준편차를 이용하여 조절한다. 실험결과 제안된 방법의 영상의 화질은 수 프레임내에 복원되고 버퍼상태도 신속히 안정화된다.

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Comparative Effects of Novel Modified Sleeper and Cross-body Stretching on Scapular Anterior Tilting and Shoulder Internal Rotation in Subjects With Anterior Tilted Scapular and Shoulder Internal Rotation Deficits

  • Yeonghun Han;Chung-hwi Yi;Woochol Joseph Choi;Oh-yun Kwon
    • 한국전문물리치료학회지
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    • 제30권1호
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    • pp.59-67
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    • 2023
  • Background: Posterior capsule tightness (PCT), commonly seen in overhead athletes, is a soft tissue adaptation that is also noted in non-throwers. PCT is associated with scapular and humeral kinematic alterations, significant restriction of shoulder internal rotation (IR) range of motion (ROM), and significant scapular anterior tilting. Sleeper and cross-body stretches (CBS) are suggested for PCT and IR deficits, and have been modified since introduction. A novel modified sleeper stretch (NMSS) was designed in this study to prevent the risk of anterior translation of the humeral head. Though the effects of posterior shoulder stretching exercise have been widely studies, to the best of our knowledge, no previous studies have investigated the effectiveness of posterior shoulder exercises in decreasing scapular anterior tilting. Objects: To compare the immediate effects of two posterior shoulder stretching exercises (NMSS and CBS) on scapular anterior tilting and shoulder IR ROM. Methods: Thirty-two subjects with anteriorly tilted scapula and IR deficits [mean age: 24.3 ± 2.5 years; 15 males and 17 females] participated in this study. Subjects were randomly assigned to either the NMSS or CBS groups. Scapular anterior tilting (at rest and at shoulder 60° active IR) and shoulder IR ROM were measured before and immediately after intervention. Results: Scapular anterior tilting significantly decreased, while the shoulder IR ROM significantly increased in both groups. However, there was no significant group-by-time interaction effect or significant difference between the groups. Conclusion: Both stretching exercises were effective in restoring shoulder IR ROM and decreasing scapular anterior tilting.

A Hand Gesture Recognition Method using Inertial Sensor for Rapid Operation on Embedded Device

  • Lee, Sangyub;Lee, Jaekyu;Cho, Hyeonjoong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제14권2호
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    • pp.757-770
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    • 2020
  • We propose a hand gesture recognition method that is compatible with a head-up display (HUD) including small processing resource. For fast link adaptation with HUD, it is necessary to rapidly process gesture recognition and send the minimum amount of driver hand gesture data from the wearable device. Therefore, we use a method that recognizes each hand gesture with an inertial measurement unit (IMU) sensor based on revised correlation matching. The method of gesture recognition is executed by calculating the correlation between every axis of the acquired data set. By classifying pre-defined gesture values and actions, the proposed method enables rapid recognition. Furthermore, we evaluate the performance of the algorithm, which can be implanted within wearable bands, requiring a minimal process load. The experimental results evaluated the feasibility and effectiveness of our decomposed correlation matching method. Furthermore, we tested the proposed algorithm to confirm the effectiveness of the system using pre-defined gestures of specific motions with a wearable platform device. The experimental results validated the feasibility and effectiveness of the proposed hand gesture recognition system. Despite being based on a very simple concept, the proposed algorithm showed good performance in recognition accuracy.

Running Control of Quadruped Robot Based on the Global State and Central Pattern

  • Kim, Chan-Ki;Youm, Young-Il;Chung, Wan-Kyun
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.308-313
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    • 2005
  • For a real-time quadruped robot running control, there are many important objectives to consider. In this paper, the running control architecture based on global states, which describe the cyclic target motion, and central pattern is proposed. The main goal of the controller is how the robot can have robustness to an unpredictable environment with reducing calculation burden to generate control inputs. Additional goal is construction of a single framework controller to avoid discontinuities during transition between multi-framework controllers and of a training-free controller. The global state dependent neuron network induces adaptation ability to an environment and makes the training-free controller. The central pattern based approach makes the controller have a single framework, and calculation burden is resolved by extracting dynamic equations from the control loop. In our approach, the model of the quadruped robot is designed using anatomical information of a cat, and simulated in 3D dynamic environment. The simulation results show the proposed single framework controller is robustly performed in an unpredictable sloped terrain without training.

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상하지 연동된 새로운 보행재활 로봇의 설계 (Design of a Novel Gait Rehabilitation Robot with Upper and Lower Limbs Connections)

  • 윤정원;본단노반디;크리스티앤드
    • 제어로봇시스템학회논문지
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    • 제14권7호
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    • pp.672-678
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    • 2008
  • This paper proposes a new rehabilitation robot with upper and lower limb connections for gait training. As humans change a walking speed, their nervous systems adapt muscle activation patterns to modify arm swing for the appropriate frequency. By analyzing this property, we can find a relation between arm swinging and lower limb motions. Thus, the lower limb motion can be controlled by the arm swing for walking speed adaptation according to a patent's intension. This paper deals with the design aspects of the suggested gait rehabilitation robot, including a trajectory planning and a control strategy. The suggested robot is mainly composed of upper limb and lower limb devices, a body support system. The lower limb device consists of a slider device and two 2-dof footpads to allow walking training at uneven and various terrains. The upper limb device consists of an arm swing handle and switches to use as a user input device for walking. The body support system will partially support a patient's weight to allow the upper limb motions. Finally, we showed simulation results for the designed trajectory and controller using a dynamic simulation tool.

A study on Real-Time Implementation of Robust Control for Horizontal Articulated Arm with Eight Axis

  • 노연 후 콩;김준홍;이희섭
    • 한국산업융합학회 논문집
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    • 제18권3호
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    • pp.139-149
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    • 2015
  • In this paper, we describe a new approach to perform real-time implementation of an robust controller for robotic manipulator based on digital signal processors in this paper. The Texas Instruments DSPs chips are used in implementing real-time adaptive control algorithms to provide enhanced motion control performance for dual-arm robotic manipulators. In the proposed scheme, adaptation laws are derived from model reference adaptive control principle based on the improved direct Lyapunov method. The proposed adaptive controller consists of an adaptive feed-forward and feedback controller and time-varying auxiliary controller elements. The proposed control scheme is simple in structure, fast in computation, and suitable for real-time control. Moreover, this scheme does not require any accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the proposed adaptive controller is illustrated by simulation and experimental results for robot manipulator consisting of dual arm with eight degrees of freedom at the joint space and cartesian space.

무인항공기의 적응제어 법칙을 이용한 피치 기동 연구 (Pitch-axis Maneuver of UAVs by Adaptive Control Approach)

  • 방효충
    • 한국항공우주학회지
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    • 제38권12호
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    • pp.1170-1176
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    • 2010
  • 본 연구는 적응제어기법을 이용한 무인항공기이 피치 자세 기동에 대한 연구 내용을 소개한다. 모델기반적응제어(Model Reference Adaptive Control)을 이용하여 피치 자세각과 엘리베이터 입력 사이의 피드백 선형화 과정에서 발생하는 불확실성을 처리하였다. 모델 불활실성 파라미터는 피드백 제어기가 작동하는 중에 적응법칙을 이용하여 추정할 수 있도록 설계 되었다. 안정화 제어기에 의해 달성되는 최종 피치 자세각에 대한 분석을 통해 폐루프 시스템의 특성을 파악할 수 있도록 하였다. 제안된 제어 기법은 기존 제어기에서 주로 채택하고 있는 선형화나 게인 스케쥴링등의 과정이 필요하지 않아 상당한 모델 오차가 존재하는 상황에서 무인항공기의 고기동 피치 제어기 설계에 도움을 줄 것으로 생각한다.

Adaptive Observer Based Longitudinal Control of Vehicles

  • Rhee, Hyoung-Chan
    • 한국산학기술학회논문지
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    • 제5권3호
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    • pp.266-272
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    • 2004
  • 본 논문에서는 주행 차량의 직진운동 제어를 위하여 관측자를 이용한 적응제어기를 제안한다. 차체중량, 시정수 등의 차량 파라미터들을 추정하기 위해 표준형 적응칙을 이용한다. 차량의 구동력 입력에서 가속도 까지의 비선형 모델을 이용하여 차량주행 속도 및 가속도 관측자를 설계한다. 제안한 관측자의 지수함수적인 안정도 및 관측자에 의거하여 설계한 적응제어기의 안정도를 리아프노브 함수 후보에 의해 입증한다. 전체 시스템의 안정도 및 차차간 상대거리/속도/가속도 오차들의 점근적인 수렴성도 수학적으로 입증하며, 제안한 방법의 타당성 및 효율성을 시뮬레이션을 통해 검증한다.

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돈분 및 남은 음식물 급여가 육계의 사료섭취 및 음수행동에 미치는 영향 (Effects of Dietary Swine Manure and Food Waste on Feeding and Drinking Behaviour of Broiler)

  • 송영한;김창혁;이용준;임종규;이영철
    • 한국축산시설환경학회지
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    • 제5권1호
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    • pp.29-36
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    • 1999
  • This study was conducted to determine the effects of dietary swine manure and food waste on feeding and drinking behaviours in broiler chicks. A total of 240 birds with 40g of initial weight were randomly assigned in the 8$\times$3 randomized complete block design and 10 birds per replicate. Extrusion recycled feeds(ERF) were prepared by extruding a mixture of 40% swine manure+40% food waste(FW)+20% corn. The birds assigned to one of the 8 dietary regimens; 0, 10, 30, 40% ERF of 20, 40, 60% FW in the place of a commercial boiler starter diet. Video recording were made after one week of adaptation period to the regimen. The tapes were played in a slow motion to examine feeding and drinking behaviour. Feeding and drinking times were greater in the day time at the night. Feeding times peaked at 4 hour intervals. Drinking time increased about 2 times on FW feeding compared to the other treatment groups. The results indicated that feeding and drinking behaviour could be influenced by the dietary regimens and that FW feeding increased drinking. The data also suggested that the FW could replace within 40% of broiler starter diet.

DSPs 기반 8축 듀얼암 로봇의 견실적응제어 (A Robust Adaptive Control of Dual Arm Robot with Eight-Joints Based on DSPs)

  • 한성현
    • 제어로봇시스템학회논문지
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    • 제12권12호
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    • pp.1220-1230
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    • 2006
  • In this paper, we propose a flew technique to the design and real-time control of an adaptive controller for robotic manipulator based on digital signal processors. The Texas Instruments DSPs(TMS320C80) chips are used in implementing real-time adaptive control algorithms to provide enhanced motion control performance for dual-arm robotic manipulators. In the proposed scheme, adaptation laws are derived from model reference adaptive control principle based on the improved Lyapunov second method. The proposed adaptive controller consists of an adaptive feed-forward and feedback controller and time-varying auxiliary controller elements. The proposed control scheme is simple in structure, fast in computation, and suitable for real-time control. Moreover, this scheme does not require any accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the proposed adaptive controller is illustrated by simulation and experimental results for a dual arm robot manipulator with eight joints. joint space and cartesian space.