• Title/Summary/Keyword: Joint inversion

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Nonlinear Adaptive Controller for Robot Manipulator (로봇의 비선형 적응제어기 개발에 관한 연구)

  • 박태욱
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.04a
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    • pp.419-423
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    • 1996
  • These days, industrial robots are required to have high speed and high precision in doing various tasks. Recently, the adaptive control algorithms for those nonlinear robots have been developed. With spatial vector space, these adaptive algorithms including recursive implementation are simply described. Without sensing joint acceleration and computing the inversion of inertia matrix, these algorithms which include P.D. terms and feedforward terms have global tracking convergence. In this paper, the feasibility of the proposed control method is illustrated by applying to 2 DOF SCARA robot in DSP(Digital Signal Processing).

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Force Feedback Control of 3 DOF Haptic Device Utilizing Electrorheological Fluid (ER 유체를 이용한 3 자유도 햅틱 장치의 힘 반향 제어)

  • Han, Y.M.;Kang, P.S.;Choi, S.B.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.213-216
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    • 2005
  • This paper presents force feedback control performance of a 3DOF haptic device that can be used for minimally invasive surgery (MIS). As a first step, a 3DOF electrorheological (ER) joint is designed using a spherical mechanism. And it is optimized based on the mathematical torque modeling. Subsequently, the master haptic device is manufactured by the spherical joint. In order to achieve desired force trajectories, model based compensation strategy is adopted for the ER master. Therefore, Preisach model fur the PMA-based ER fluid is identified using experimental first order descending (FOD) curves. A compensation strategy is then formulated through the model inversion to achieve desired force at the ER master. Tracking control performances for sinusoidal force trajectory are presented, and their tracking errors are evaluated.

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Kinematic Difference between the Lower Limb Joints and the Lower Extremities Given Elderly Women's Walking through the Lower-limb Resistance Exercises (하지 저항운동을 통한 여성고령자 보행 시 하지관절 및 분절의 운동학적 차이)

  • Seo, Se-Mi
    • The Journal of the Korea Contents Association
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    • v.9 no.12
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    • pp.364-375
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    • 2009
  • The purpose of this study is to offer basic data for the fall prevention by analyzing the kinematic difference between the lower limb joints and the lower extremities in elderly people's walking given the lower-limb resistance exercises. For this, three-dimensional image analysis was carried out by selecting 7 elderly women from over 70s to under 80 years old. To obtain the three-dimensional location coordinates in the lower limb joints and the lower extremities, it shot with 100Hz/s by using MCU(Qualisys, Sweden) camera. The shot image gained raw data on the location coordinates by using QTM(Qualisys, Sweden). As a result of calculating three-dimensional angle by using program of Matlab 6.5, the following conclusions were obtained. Flexion and extension in the thigh and the lower-leg extremities were indicated to be big in motion of flexion after exercising at E5. Foot segment indicated statistical difference while showing eversion at E4. Knee joints showed flexion at E4 after exercising. Ankle joints showed statistical difference while indicating motion in inversion at E3 and in eversion at E4(p<.05).

Comparative Study on Usefulness of SPAIR and STIR Fast SE T2-weighted 3T Magnetic Resonance Imaging (3T 고속스핀에코 T2강조영상에서 지방소거 반전회복기법의 유용성 연구 - SPAIR와 STIR와의 비교 -)

  • Lee, Hoo-Min;Yoon, Joon;Yeo, Young-Bok
    • Journal of radiological science and technology
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    • v.33 no.1
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    • pp.45-50
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    • 2010
  • In this study, we compared the clinical usefulness of SPAIR (Spectral Adiabatic Inversion Recovery) and STIR (Short TI Inversion Recovery) to evaluate the fat tissues precisely. The images of brain axial (n = 20), lumber spine sagittal (n = 20), hip joint coronal (n = 17) and knee joint (n = 25) were obtained by turbo spin echo T2 weighted method on 3T magnetic resonance image. The signal intensity (SI) values were measured using region of interest in fat, muscle tissue, and background noise. The inhomogeneity values were measured using the standard deviation (SD) value divided by the mean values. SD signifies the amount of error which is similar to the imaging heterogeneity. In brain axial images, the SPAIR showed more superior SI and inhomogeneity results than the STIR. In spine, hip and knee images, STIR showed more excellent SI results, but poor inhomogeneity than the SPAIR.

The Effect of Incidence of Ankle Sprains on Both Leg Length Inequalities and Range of Motion of Ankle Joint in 20's Female University Students (20대 여대생의 양다리길이차이 및 발목관절가동범위가 발목 염좌 발생률에 미치는 영향)

  • Park, Jong-Hang;Jeong, Yeon-Woo;Kim, Tae-won
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.21 no.1
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    • pp.29-35
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    • 2015
  • Background: The purpose of this study was conducted to investigate the effect of incidence of ankle sprains on both leg length inequalities and range of motion of ankle joint in 20's female university students. Methods: 20's female university students were targeting 32 people attending K university in Gwangju. Both leg length inequality was measured using a tape measure, ranges of motion of ankles was measured using a goniometer. Results: The ankle sprain incidence was quite high, with 56.25% (n=18) for the right ankle, 34.38% (n=11) for the left ankle, and 9.38% (n=3) for both. As for the difference between the ankle sprain incidence and both leg length, the average value of the right leg was $83.08{\pm}3.69$, the average value of the left leg was $84.28{\pm}3.27$, making the right leg shorter than the left by 1.2cm with a higher incidence and showing a positive statistical correlation between the two (p<.05). Also showed that there was a negative statistical correlation between ankle sprain incidences and the inversion range of motion spread of the right ankle (p<.05). Conclusion: The incidence of ankle sprains was higher for the larger the difference between both leg length inequality. In addition, the smaller the inversion range of motion spread of the right ankle, the higher the incidence of ankle sprains. Therefore, The evidence suggests that the incidence of ankle sprains can be reduced by recommending stability and efficient exercises that take into consideration the both leg length as well as the ranges of motion of ankle joints.

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The Effect of Elastic Therapeutic Taping on Lower Limb Kinematics during a Cross Cutting Movement from Landing in Subjects with Chronic Ankle Instability (탄력 테이핑이 만성 발목 불안정 환자의 착지 후 방향 전환 시 하지 관절 움직임에 미치는 영향)

  • Jo, Tae-Seong;Kim, Tack-Hoon;Choi, Houng-Sik;Roh, Jung-Suk
    • Journal of the Korean Society of Physical Medicine
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    • v.12 no.4
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    • pp.1-9
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    • 2017
  • PURPOSE: This study investigated the effect that an elastic therapeutic taping treatment given to patients with chronic ankle instability had on the vertical ground reaction force, center of pressure, and range of motion in the ankle, knee and hip joints, during a Cross-cutting movement from landing. METHODS: This study analyzed 12 able-bodied adults and 12 patients with chronic ankle instability classified by using the Cumberland tool in the motion analysis laboratory, Hanseo University. The experiment was conducted under two conditions elastic taping and no treatment. In order to analyze the difference between the groups. An independent t-test was performed at p>.01. RESULTS: Plying an elastic therapeutic taping to the patients with chronic ankle instability significantly decreased the range of joint motion in the inversion of the ankle joint, the flexion of the knee joint, and the flexion and internal rotation of the hip joint during a cross-cutting movement from landing in comparison with the able-bodied adults p<.01. This restriction in the range of motion decreased the center-of-pressure trajectory length of patients with chronic ankle instability p>.01. CONCLUSION: An elastic therapeutic taping treatment given to patients with chronic ankle instability causes ankle stability to increase during a cross-cutting movement from landing.

Different Biomechanical Characteristics in Proprioception, Muscle Strength, and Time to Peak Torque at Velocity of 300°/sec of the Ankle Joint in People With or Without Functional Ankle Instability (각속도 300°/sec에서 기능적 발목불안 유무에 따른 고유수용성감각, 발목 근력, 그리고 최고 회전력까지 걸리는 시간의 생체역학적 특성 차이)

  • Park, Eun-Young;Kim, Won-Ho
    • Physical Therapy Korea
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    • v.20 no.3
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    • pp.45-53
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    • 2013
  • The purpose of this study was to examine the differentiation of proprioception, invertor and evertor muscle strength, and time to peak torque at a velocity of $300^{\circ}/sec$ of the ankle joint in people with or without functional ankle instability (FAI). Nineteen subjects with a history of ankle sprain participated. All subjects were divided into FAI group ($n_1=9$, Cumberland ankle instability tool (CAIT)${\leq}24$) and a control group ($n_2=10$) based on their CAIT scores. Isokinetic dynamometer was used to measure the sense of active joint position of the ankle at mid-range and end-range of an inversion motion and invertor as well as the evertor muscle strength and time to peak torque at $300^{\circ}/s$. The FAI group showed a statistically reduction in invertor and evertor muscle strength and time to peak torque when compared to the control group (p<.05). Muscle strength and time to peak torque of the invertor and evertor, as well as the sense of active joint position at end-range were also lower in the FAI group than in the control (p<.05). Correlations between CAIT score and position sense at end-range (r=-.577) and invertor muscle strength (r=.554) were statistically significant (p<.05). Individuals with FAI showed reduction in invertor and evertor muscle strength and recruitment time as well as in proprioception of the ankle joint. Thus, proprioception and invertor and evertor muscle strength of the ankle joint at fast angular velocity may be investigated when examining and planning care for individuals with FAI.

Effect of Kinesiotaping on The Ankle Proprioception in Normal Subjects (일반인의 발목관절에 키네시오 테이핑 적용이 고유감각에 미치는 영향)

  • Lee, Suk-Ju;Lee, Sin-Young;Lee, Da-Seul;Oh, Joo-Young;Kim, Jang-Gon
    • Journal of Korean Physical Therapy Science
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    • v.23 no.1
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    • pp.18-23
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    • 2016
  • Purpose : The purpose of the present study is to report the effect of proprioception of ankle after kinesiotaping application on ankle. Method : This study has conducted to target 30 average adult subjects with no damage to the ankle joint (16 males and 14 females). The group is divided into experimental group and sham groups in random way. The subjects in the experimental group are applied taping kinesiology on ankle joint. The subjects in the sham group are applied a sham taping on the ankle joint which is not actually affected for real ankle joint problem. Each subjects in both groups has tree trials in plantarflexion, dorsiflexion, inversion, and eversion before and after application of the kinesiotaping or sham taping of the bare footed ankle. The outcome were determined from the difference between the target angle and the trial angle produced by the subject. Results : These results from the experiment shows that the experimental group compared to the difference in kinesiotaping angle values were significantly different from each dorsiflexion (DF), eversion (EV) (p<.05). Otherwise, in the sham group did not produce significant differences in any joint movement. In addition, when we compared between two groups (the experimental and sham groups), it did not show that there was significant differences. Conclusion : First, there is no significant difference between the sham group and kinesiotaping group after proprioceptive tests. Second, even though there is no significant outcome in statistical analysis, there is actual differences in the experiment. This result might be ceiling effect, and if the kinesiotaping were applied to actual ankle injury patients, this taping treatment could be very effective for curing this patient.

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