• Title/Summary/Keyword: posture change

Search Result 419, Processing Time 0.023 seconds

Biomechanical Analysis of Injury Factor According to the Change of Direction After Single-leg Landing

  • Kim, Jong-Bin;Park, Sang-Kyoon
    • Korean Journal of Applied Biomechanics
    • /
    • v.26 no.4
    • /
    • pp.433-441
    • /
    • 2016
  • Objective: The purpose of this study was to understand the injury mechanism and to provide quantitative data to use in prevention or posture correction training by conducting kinematic and kinetic analyses of risk factors of lower extremity joint injury depending on the change of direction at different angles after a landing motion. Method: This study included 11 men in their twenties (age: $24.6{\pm}1.7years$, height: $176.6{\pm}4.4cm$, weight: $71.3{\pm}8.0kg$) who were right-leg dominant. By using seven infrared cameras (Oqus 300, Qualisys, Sweden), one force platform (AMTI, USA), and an accelerometer (Noraxon, USA), single-leg drop landing was performed at a height of 30 cm. The joint range of motion (ROM) of the lower extremity, peak joint moment, peak joint power, peak vertical ground reaction force (GRF), and peak vertical acceleration were measured. For statistical analysis, one-way repeated-measures analysis of variance was conducted at a significance level of ${\alpha}$ <.05. Results: Ankle and knee joint ROM in the sagittal plane significantly differed, respectively (F = 3.145, p = .024; F = 14.183, p = .000), depending on the change of direction. However, no significant differences were observed in the ROM of ankle and knee joint in the transverse plane. Significant differences in peak joint moment were also observed but no statistically significant differences were found in negative joint power between the conditions. Peak vertical GRF was high in landing (LAD) and after landing, left $45^{\circ}$ cutting (LLC), with a significant difference (F = 9.363, p = .000). The peak vertical acceleration was relatively high in LAD and LLC compared with other conditions, but the difference was not significant. Conclusion: We conclude that moving in the left direction may expose athletes to greater injury risk in terms of joint kinetics than moving in the right direction. However, further investigation of joint injury mechanisms in sports would be required to confirm these findings.

A Study on the Development of In-Socket Pressure Change Measurement Sensor for Estimation Locomotion Intention of Intelligent Prosthetic leg User (지능형 대퇴의족 사용자의 보행 의도 추정을 위한 소켓 내 압력 변화 측정 센서 개발에 관한 연구)

  • Park, Na-Yeon;Eom, Su-Hong;Lee, Eung-Hyuk
    • Journal of IKEEE
    • /
    • v.26 no.2
    • /
    • pp.249-256
    • /
    • 2022
  • The prosthetic leg is a device that performs walking instead of a amputated lower limb, and require a change in locomotion mode by providing the user's intention to respond to a discontinuous locomotion environment. Research has been conducted to detect the users' intentions through biomechanical features inside the socket that directly contacts the cut site in demand for natural locomotion mode changes without external control equipment. However, there is still a need for a sensor system that is suitable for the internal environment of the main body and socket of the cut site. Accordingly, this paper proposed a film-type sensor system that is suitable for the main body characteristics of the cut site, is not affected by the temperature and humidity conditions inside the socket, and is easy to manufacture in various sizes. The proposed sensor is manufactured base on Velostat film and takes into account the pressure measurement characteristics that vary with size. Through the experiment, the change in the internal pressure of the socket due to the intentional posture performance of the wearer was measured, and the possibility of detecting the intention to change the locomotion mode was confirmed.

Analysis and Design of Jumping Robot System Using the Model Transformation Method

  • Suh Jin-Ho;Yamakita Masaki
    • Journal of Electrical Engineering and Technology
    • /
    • v.1 no.2
    • /
    • pp.200-210
    • /
    • 2006
  • This paper proposes the motion generation method in which the movement of the 3-links leg subsystem in constrained to slider-link and a singular posture can be easily avoided. This method is the realization of jumping control moving in a vertical direction, which mimics a cat's behavior. To consider the movement from the point of the constraint mechanical system, a robotics system for realizing the motion will change its configuration according to the position. The effectiveness of the proposed scheme is illustrated by simulation and experimental results.

The Intuitive Change of Virtual Wand Style in Spatial Sketch System (가상 완드 스타일의 직관적인 변형을 지원하는 공간 스케치 시스템)

  • Nam, Sang-Hun;Chai, Young-Ho
    • 한국HCI학회:학술대회논문집
    • /
    • 2009.02a
    • /
    • pp.56-61
    • /
    • 2009
  • According to the target object for designer to sketch, an effective style or shape of input device can be defined differently. The general spatial sketching system that support various types of wand assist sketching effectively as changing suitable wand shape to the part of a target object. We suggest the idea of changing wand style by altering the posture of a 3D wand. This allows a designer to work in an intuitive way without being interrupted by complicated menus. We implement the various wand styles to the spatial sketching system with cubic-based drawing technique.

  • PDF

Filing Experiments and Structural Analysis of Human Body (사격시험 및 인체구조해석)

  • Lee, Se-Hoon;Choi, Young-Jin;Choi, Eui-Jung;Chae, Je-Wook;Lee, Young-Shin
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.31 no.7 s.262
    • /
    • pp.764-776
    • /
    • 2007
  • On the human-rifle system, the human body is affected by the firing impact. The firing impact will reduce the firing accuracy and change the initial shooting posture. Therefore the study of biomechanical characteristics using human-rifle modeling and numerical investigation is needed. The musculoskeletal model is developed by finite element method using beam and spar elements. In this study structural analysis has been performed in order to investigate the human body impact by firing of 5.56mm small caliber machine gun. The firing experiments with the standing shooting postures were performed to verify analytical results. The result if this study shows analytical displacements of the human-rifle system and experimental displacements of the real firing. As the results, the analytical displacement and stress of human body are presented.

A Study on the Recruitment Pattern and Changes of the Role Assigned to Lower Extremity Muscles by EMG Analysis (근전도를 이용한 하지근육의 동원형태 및 역할분담 분석에 관한 연구)

  • 황규성;정의승;이동춘
    • Proceedings of the ESK Conference
    • /
    • 1995.04a
    • /
    • pp.72-83
    • /
    • 1995
  • This study are to investigate the variations of the recruitment patterns of the nine lower extremity muscles, and to analyze the changes of the role assigned to each muscle during the seated posture. For exertion levels, the transition point of type F more unit of each muscle is inferred by analyzing the electromyogram at the seated postures. Also, for predetermined seated foot operations exertion levels, the recruitment pattern and the changes of the role assigned are identified in the continuous exertion, by analyzing the electromyogram change sdue to the accumulated muscle fatigue. The developed model can be used to design and to assess the pedals and foot-related equipments design.

  • PDF

The Analysis of Risk for Musculoskeletal Inuries in Combine Harvesting Operation Using a Digital Human Model (디지털 인체 모델을 이용한 콤바인 수확 작업의 근골격계 상해요소 분석)

  • Kim, Young-Jin;Rim, Yong-Hoon;Lee, Kyoung-Sook;Choi, Chang-Hyoun;Mun, Joung-Hwan
    • Journal of Biosystems Engineering
    • /
    • v.35 no.3
    • /
    • pp.206-213
    • /
    • 2010
  • The purpose of this study is to analyze musculoskeletal injuries in combine harvesting operation using a digital human model. In order to analyze problems in combine harvesting operation, the operations were broken into 5 work processes and then we preformed ergonomic and biomechanical analyses such as RULA test, Comfort Assessment and joint kinetic analysis for the each process. As a result, there was a clear need to change the combine operating environment, as the RULA score ranged from 4 to 7. In addition, we could find two major musculoskeletal injury factors which are the standing posture with upperbody forward tilting and inappropriate location of operating levers.

Movement Characteristic Analysis for Unconstrained Sleep Efficiency Analysis Based on the Smartphone (무구속 수면효율 분석을 위한 스마트폰 기반 움직임패턴 특성분석)

  • Kim, Do Yoon;Shin, Hangsik
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.63 no.7
    • /
    • pp.940-944
    • /
    • 2014
  • In this research, we designed representative motion patterns that possibly occurred in sleep situation and evaluated the feasibility of the smartphone based movement recording technique. For this, we designed 7 motions such as posture change, head movement, arm movement (vertical, horizontal), leg movement and hand movement (flipping, folding). Movement was recorded by using the smartphone and the actimetry device simultaneously for comparing the feasibility of smartphone based recording. As a result of experiment, we found that the smartphone based movement recording well reflects the body movement, however, it shows the limitation in recording the small local movement such as hand motion compared with the reference actimetry device, Actiwatch.

Application of an Ergonomic Design of Work space Layout Using 3-Dimensional Human Model (인간공학적 작업공간 설계를 위한 CAD 응용방안)

  • Lee, Myeon-U;Lee, Dal-Ho;Jang, Seong-Rok
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.12 no.2
    • /
    • pp.13-19
    • /
    • 1986
  • The purpose of this paper is to develop a 3-dimensional human model, an ergonomic CAD (Computer-Aided Design) system which would be very helphul in ergonomic design. An interactive program was developed, in which a user could change layout, body size, skin volume, and posture of the human model. As an example, effect of inclination of a steering wheel on visibility of a display panel was demonstrated. he result showed that ergonomic design can be aided by the 3-dimensional human model, and by the perspective graph by which design and evaluation process can be carried out more effectively.

  • PDF

An Isometric Shape Interpolation Method on Mesh Models (메쉬 모델에 대한 아이소메트릭 형상 보간 방법)

  • Baek, Seung-Yeob;Lee, Kunwoo
    • Korean Journal of Computational Design and Engineering
    • /
    • v.19 no.2
    • /
    • pp.119-128
    • /
    • 2014
  • Computing the natural-looking interpolation of different shapes is a fundamental problem of computer graphics. It is proved by some researchers that such an interpolation can be achieved by pursuing the isometry. In this paper, a novel coordinate system that is invariant under isometries is defined. The coordinate system can easily be converted from the global vertex coordinates. Furthermore, the global coordinates can be efficiently recovered from the new coordinates by simply solving two sparse least-squares problems. Since the proposed coordinate system is invariant under isometries, then transformations such as global rigid trans-formations, articulated posture deformations, or any other isometric deformations, do not change the coordinate values. Therefore, shape interpolation can be done in this framework without being affected by the distortions caused by the isometry.