• Physical Therapy Korea
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• v.13 no.3
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• pp.67-74
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• 2006

The purpose of this study was to investigate the effects of walking aid on hemiplegic gait of chronic stroke patients. Twelve stroke patients participated in this study. Physiological cost index (PCI), gait speed, and climbing stairs with and without walking aid were measured and analyzed. The results showed that walking with walking aid significantly improved gait speed and reduced physiological cost index and time needed to climb stair (height 7 cm) in comparison with a walking without walking aid. In conclusion, walking aid may improve the speed and efficiency of hemiplegic gait in chronic stroke patients.

• Proceedings of the KIEE Conference
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• 2006.04a
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• pp.312-314
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• 2006

Researches on biped robot walking have been mostly focusing on walking on even surfaces. Therefore, robot walking has been only realized on pre-specified spaces with pre-specified movements according to the previous researches. In this paper a walking system for a biped robot using fuzzy system and neural networks to overcome those constraints. The system enables biped walking to be possible in various environments and with more complicated obstacels. For the purpose, a walking robot should recognize its surrounding environment and determine its movement. In the proposed system, a robot dynamically generates its walking trajectories of each joint by using neural networks when facing new obstacle such as stairs, and it maintains its walking stability by using closed loop fuzzy control system which manipulates the waist joints.

• Proceedings of the KSME Conference
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• 2000.04a
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• pp.548-555
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• 2000

The dynamic walking and the inverse dynamics of the biped walking robot is investigated in this paper. The biped robot is modeled with 14 degrees of freedom rigid bodies considering the walking pattern and kinematic construction of humanoid. The method of the computer aided multibody dynamics is applied to the dynamic analysis. The equations of motion of biped are initially represented as terms of the Cartesian coordinates, then they are converted to the minimum number of equations of motion in terms of the joint coordinates using the velocity transformation matrix. For the consideration of the relationships between the ground and foot, the holonomic constraints are added or deleted on the equations of motion. The number of these constraints can be changed by types of walking pattern with three modes. In order for the dynamic walking to be stabilizable, optimized trunk positions are iteratively determined by satisfying the system ZMP(Zero Moment Point) and ground conditions.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.882-887
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• 2008

In this paper, the dependency of energy efficiency on the walking/running pattern and the walking/running period is analyzed though simulations of walk, trot and gallop. A quadruped animal has its own original features in the walking pattern and the walking period for adaptation to the environment. The robot model used in the simulations has three active joints and one passive spring-loaded joint at each leg, which is based on the actual quadruped robot, HUNTER (Hanyang UNiversity TEtrapod Robot), developed in the lab. Also included is the dependency of energy efficiency on the walking period in trot.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.9
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• pp.959-966
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• 2009

An essential consideration when analyzing the gait of walking robots is their ability to maintain stability during walking. Therefore, this study proposes a vertical waist-jointed walking robot and gait algorithm to increase the gait stability margin while walking on the slope. First, the energy stability margin is compared according to the posture of the walking motion on slope. Next, a vertical waist-jointed walking robot is modeled to analyze the stability margin in given assumption. We describe new parameters, joint angle and position of a vertical waist-joint to get COG (center of gravity of a body) in walking. Finally, we prove the superiority of the proposed gait algorithm using simulation and conclude the results.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.4
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• pp.310-318
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• 2008

This paper presents a parallel typed walking robot to improve walking space and stability region. The robot is designed by inserting an intermediate mechanism between upper leg mechanism and lower leg mechanism. The leg mechanism is composed of three legs and base, which form a parallel mechanism with ground. Seven different types of walking robot are invented by combining the leg mechanisms and an intermediate mechanism. Topology is applied to design the leg mechanism. A motor vector is adopted to determine Jacobian and a wrench vector is used to analyze dynamics of the robot. We explore the stability region of the robot from the reaction force of legs and compute ZMP including the holding force to contact the foot to a wall. This investigates a walking stability when the robot walks on the ground as well as on the wall. We examine the walking space generated by support legs and by swing legs. The robot has both a large positional walking space and a large orientational walking space so that it can climb from a floor up to a wall.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.10
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• pp.885-890
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• 2015

Walking on split-belt treadmill has been applied to study walking disabilities, such as osteoarthritis (OA), to show asymmetric walking characteristics. In this study, we compared asymmetric walking in OA patients with healthy subjects under split-belt conditions and examined the reproduction of walking asymmetry in OA. Seven OA patients were instructed to walk at four frequencies, while four healthy subjects walked on a treadmill with tied-belt and split-belt conditions. To compare walking asymmetries, kinetic and kinematic measurements were made using force-plates and motion capture cameras, and subsequently center of mass (CoM) velocity, mechanical work and potential energy were calculated. Horizontal velocity change during split-belt walking of healthy subjects was similar to OA patients. Difference of mechanical work during single support phase occurred due to fall of CoM in fast belt. OA walking asymmetry could be reproduced by reducing differences of belt speeds to prevent rapid fall of CoM.

• The Journal of Korean Physical Therapy
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• v.26 no.5
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• pp.372-378
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• 2014

Purpose: The aim of this study was to evaluate the effect of side walking training with an elastic-band on gait and balance ability of stroke patients. Methods: Twenty three patients with stroke participated in the study. Participants were randomly assigned to the side walking with elastic-band group (n=7), the side walking without elastic-band group (n=8), and the walking on the treadmill group (n=8);. 10 m walking test (10MWT), Dynamic Gait Index (DGI), Berg Balance Scale (BBS), and modified Functional Reach Test (mFRT) were performed for evaluatione of pre- and post-intervention in gait and balance ability of participants. Results: Significantly differences in 10 MWT, DGI, BBS, and mFRT were observed between pre- and post-intervention in three groups (p<0.05). Improvement of pre- and post-intervention of mFRT showed significant difference (p<0.05). The highest rate of change was observed in the side walking with elastic-band group and rate of change showed in the order of the side walking without elastic-band group, walking on the treadmill group. Conclusion: This study suggests that side walking training with an elastic-band may help to improve gait and balance ability of stroke patients.

• Korean Journal of Adult Nursing
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• v.20 no.4
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• pp.561-572
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• 2008

Purpose: To examine the effects of power walking exercise on fatigue and overweight in college students with Taeumin constitution. Methods: According to results of the constitution diagnosis (QSCC II), 58 students who were identified as Taeumin, whose BMI was over 23 were assigned to one of three groups. The power walking group walked fast at a speed of 7,000 steps per hour using a pedometer, and the walking group walked at a speed of 5,000 steps per hour. There was no treatment with control group. Each group's fatigue level, blood lipids and body composition before and after the experiment were compared and analyzed. Results: Total fatigue and total cholesterol decreased significantly in the power walking group compared to the walking group and the control group. Weight decreased significantly in the power walking group compared to the control group, and percentage of body fat decreased significantly in both the power walking group and the walking group compared to the control group. Conclusion: When power walking exercise was used with overweight Taeumin students, fatigue, blood lipid, weight and percentage of body fat decreased significantly.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.10
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• pp.56-64
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• 2009

This paper presents a parallel typed walking robot which can walk in omni-direction and climb from a floor to a wall. We design a six D.O.F leg mechanism composed of three legs, which form a parallel mechanism with a base and a ground to generate arbitrary poses. Optimal design is conducted to maximize the walking space and the dexterity, which are normalized by the stroke of leg. Kinematic parameters are found to maximize the weighted optimal objectives. We design a triple parallel mechanism robot by inserting Stewart platform between the upper leg mechanism and the lower leg mechanism and examine the gaits when the robot walks on the ground and climbs from a floor to a wall. The analysis of walking space and dexterity for each gait shows that the triple parallel walking robot has a large walking space with a large stability region. We explore the possibility that the robot can climb from a floor to a wall. Investigating the gaits for the six steps proves that the robot can lift the foot up to the wall by combining the orientational walking space generated by three parallel mechanisms.