• Journal of the Institute of Electronics Engineers of Korea SC
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• v.43 no.3 s.309
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• pp.16-24
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• 2006

In this paper, fault-tolerant gait planning of a hexapod robot for walking over irregular terrain is presented. The failure concerned in this paper is a locked joint failure for which a joint in a leg cannot move and is locked in place. Based on the previously proposed fault-tolerant tripod gait for walking over even terrain, fault-tolerant follow-the-leader(FTL) gaits are proposed for a hexapod robot with a failed leg to be able to walk over two-dimensional rough terrain, maintaining static stability and fault tolerance. The proposed FTL gait can have maximum stride length for a given foot position of a failed leg, and yields better ditch crossing ability than the previously developed gaits. The applicability of the proposed FTL gait is verified by using computer graphics simulations.

• Journal of the Korean Society of Physical Medicine
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• v.7 no.1
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• pp.49-58
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• 2012

Purpose : The purpose of this study was to investigate the effects of trunk stabilization exercise using swiss ball and core stabilization exercise on balance and gait in elderly women. Methods : Subjects 19 elderly women were randomly divided by the swiss ball exercise group (n=10) and the core stabilization exercise group (n=9). In a period of 4 weeks, they took trunk stabilization exercise using swiss ball and core stabilization exercise for 60 minutes 3 times a week. Balance and gait were measured by Functional Reach Test (FRT), One Leg Stand Test with Open Eye (OLSTOE), One Leg Stand Test with Closed Eye (OLSTCE), Timed Up and Go Test (TUG) and 6 m Walking Test (6MWT). These tests were measured at before exercise, 4 weeks after exercise and after the follow-up period of 2 weeks. Results : As a result, in all measurement values there was no significant difference in two groups (p>.05). In FRT, TUG, OLSTOE and 6MWT before exercise and 4 weeks after exercise, there was significant difference in both of two groups (p<.05). Moreover, according to results from 4 weeks after exercise and after the follow-up period of 2 weeks, without any particular exercise, in FRT and 6MWT there was no significant difference (p>.05). Conclusion : These finding indicate that trunk stabilization exercise using swiss ball could improve balance and gait in elderly women. Accordingly, In this study trunk stabilization exercise using swiss ball and core stabilization exercise is judged to be used for elderly people with gait and balance problems to prevent hurts from fall.

• Journal of the Korea Convergence Society
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• v.11 no.1
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• pp.57-63
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• 2020

The purpose of this study was to investigate the effects of sling exercise convergence with passive vibration on balance and gait in stroke patients. One time 35 minutes three times a week for six weeks. The sling exercise experimental group and the control group were divided into eight members. Balance and gait were measured. There was a significant difference between the eyes open standing and the eyes closed standing in the comparison between the experimental group and the control group. The experimental and control groups showed significant differences in the groups of eyes open standing and eyes closed standing, limits of stability and gait speed before and after intervention. Vibration sling exercise may help to improve the balance and gait of stroke patients. In the future, many patients, various frequencies, and effective exercise periods are needed.

• Korean Journal of Applied Biomechanics
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• v.17 no.1
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• pp.111-119
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• 2007

The purpose of this study was to investigate muscle activity and gait pattern in lower limb depending on the outsole of heel rockers. Fifteen healthy men volunteered for this experiment. Each subject performed totally three trails with two pairs of different heel rocker shoes and a pair of normal running shoes at speed of 1.33m/s for 1 minute during walking on a treadmill. Kinematic data gathered in 100Hz was recorded and analyzed by using the 3D motion capture system to measure the trunk tilt and joint angle of the right lower limb. And the lower extremity muscle activities were simultaneously recorded in 1000Hz and assessed by using EMG. The statistical analysis was the one-way ANOVA with the repeated measures to compare among the three kinds of shoes. The level of statistical significance for all tests was 0.05. Joint angle of lower limb was showed statistically significant different in MST(hip joint), LHS(ankle joint), and RTO(knee and ankle joint). Muscle activity of rectus femoris and biceps femoris was statistically increased in both heel rocker shoes during gait cycle on treadmill. The maximum peak time of tibialis anterior in the negative heel rocker showed the delay of approximately 23.8%time than normal shoes. Gait pattern variability of the negative heel rocker was increased in the first half of the stance phase and the variability of the positive heel rocker was increased in the terminal stance phase. In Conclusion, stability was decreased in between joints of lower limb on positive heel rocker than negative heel rocker. This study found that there were different joint angle, muscle activity, gait pattern and coordinate system of the lower limb in each kind of shoes. These unstability affected the lower extremity and the whole body. A further study has to be continued with study of rehabilitation and exercise for a long-term.

• Korean Journal of Applied Biomechanics
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• v.23 no.1
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• pp.85-90
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• 2013

Efficient gait is compensate for a lack of exercise, but the wrong walking can cause disease that joints, muscles, brain and body structure(Scott & Winter, 1990). Also many researchers has been studied gait of positive mechanism using analytical methods kinetic, kinematic. This study is to identify nature of knee adduction moment, depending on different foot progression angle and the movement of rotation of pelvis and body. Health study subject conducted intended walking with three different angles. The subjects of this study classified three types of walking; walk erect, pigeon-toed walk and an out-toed gait. Ten university students of K without previous operation and disease record selected for this study. For accuracy of this study, three types of walking carried out five times with 3D image analysis and using analysis of ground reaction force to analyze nature of knee adduction moment and the movement of rotation of pelvis and body. Firstly, the HC(heel contact) section value of intended walk erect, pigeon-toed walk and an out-toed gait was not shown statistically significant difference but TO(toe off) section value was shown that the pigeon-toed walk statistically significant. The value of pigeon-toed walk was smallest knee adduction moment(p< 0.005). Secondly, X axis was the change of rotation movement body and pelvis when walk erect, pigeon-toed walk and an out-toed gait. Shown statistically Y axis was not shown statistically significant but Z axis statistically significant(p<0.05). These result show the significant differences on TO section when walking moment reaches HC, it decides the walking types and rotates the foot.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.422-428
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• 2018

This study was conducted to investigate the effects of trunk stability exercise on knee function, balance and gait in patients who underwent total knee arthroplasty. The subjects of this study were recruited from individuals diagnosed with degenerative arthritis who had undergone total knee arthroplasty. Overall, 24 patients were randomly divided into a control groups and an experimental groups (12 each). The trunk stability exercise was conducted for 4 weeks with three exercises developed in a previous study. The measurement tools used were knee function measurements based on the Lysholm knee score, balance ability measured using a test of TUG and OLS, and a walking ability test measured using a 10MWT. Pre and post test results were within groups were compared using the paired t-test, whole differences between groups were compared using the independent t-test. The experimental group showed significantly enhanced results relative to the control group (p<0.05). Based on these results, trunk stability exercise in parallel with knee joint therapy effectively improves the recovery of patients with total knee arthroplasty.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.574-577
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• 2001

This paper presents the comparison of FRI(Foot Rotation Indicator) point and ZMP(Zero Moment Point) in biped robot stability. We showed FRI may be employed as a useful tool in stability analysis in biped robot. Also, we proposed the balancing joint trajectory derived from FRI point equation for stable gait. The numerical calculation routines and walking algorithms for simulation are performed by MATLAB. The procedure is composed of the leg trajectory planning, the generation of balancing trajectory, and the verification of dynamic stability.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.04b
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• pp.490-496
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• 1995

A four-legged mobile robot can move on the plain terrain with mobility and stability, but if there exist any obstacles on the terrain of the motion direction, it takes extra times for a mobile robot to cross those obstacles and the stability should be considered during motion. The main objevtive is the study of a quadruped which can cross obstacles with better mobility, stability and fuel economy than any other wheeled or tracked vehicles. Vertical step, isolated wall and ditch are the basic obstacles and by understanding those three cases perfectly, a quadruped can move on any mixed rough terrain as 4-legged animal moves. Each leg of a determine the crossing capability in a static analysis. A quadruped can be simplified with links and joints. By applying the research method, a quadruped can determine the control procedures as soon as it receives the terrain informations from scanner and finally can be moved as animals move with mobility and stability.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.235-236
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• 2008

• Korean Journal of Applied Biomechanics
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• v.21 no.2
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• pp.223-230
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• 2011

The purpose of this study was to analysis the effect of form and hardness of outsoles on the motion of the lower extremity joints and on foot pressure during gait. The subjects were 15 women(mean age, $48.5{\pm}2.4$ years), who had no serious musculoskeletal, coordination, balance or joint/ligament problems within 1 year prior to the study. The pelvic tilt, joint angles at the lower extremities and the vertical ground reaction force(GRF) were compared during gait with 3 types of shoes (A, B, C) by using one-way repeated ANOVA(p<.05). During gait, the peak tilt angle and the range of motion(ROM) of the ankle and knee joints were found to be significantly different among the 3 types of shoes. The type C shoes showed a significantly lower mean second maximum vertical GRF than types A and B. The curved outsoles of type C shoes, which had a form and hardness different from those of A and B, was designed strategically for walking shoes to provide stability to the Additionally, type C induced the dispersion of eccentric pressure and made the center of pressure roll over to the center line of the foot.