• Journal of Korean Physical Therapy Science
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• v.10 no.2
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• pp.7-16
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• 2003

The purpose of this study was to investigate the effect of Treadmill Training with FES(TTF) on walking velocity, gait endurance, and energy expenditure index(EEI) of hemiplegia patients with foot drop. Two subjects with hemiplegia participated in this study. They took walking excercise 5 times per week for 8 weeks. One time excercise spent 30minutes. The theraputic effect was evaluated by how many seconds they needed to walk 10 meters, how far they could walk for 12 minutes, and how much they spent energy in walking for 12 minutes. Two cases were examined before, after 4 week, and after 8 week, walking training. The results of this study are as follows; 1) Walking velocity : Case 1 increased from 0.52m/sec before walking training to 0.83m/sec after 8 weeks. Case 2 increased from 0.58m/sec to 0.92m/sec. 2) Gait endurance : Case 1 increased from 383.23m to 625.53m. Case 2 increased from 410.19m to 693.47m. 3) EEI : For comfortable walking condition, Case 1 decreased from 0.98beats/min to 0.71beats/min, and Case 2 decreased from 0.93beats/min to 0.68beats/min. For maximum walking condition, Case 1 decreased from 0.93beats/min to 0.67beats/min, and Case 2 decreased from 0.91beats/min to 0.61beats/min. The findings suggest that hemiplegia patients can improve their walking velocity, gait endurance and energy expenditure index through TTF.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.5
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• pp.511-518
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• 2009

The surveillance robot has been an important component in the field of service robot industry. In the surveillance robot technology, one of the most important technology is to identify a person. In this paper, we propose a gait recognition method based on contourlet and fuzzy LDA (Linear Discriminant Analysis) for surveillance robots. After decomposing a gait image into directional subband images by contourlet, features are obtained in each subband by the fuzzy LDA. The final gait recognition is performed by a fusion technique that effectively combines similarities calculated respectively in each local subband. To show the effectiveness of the proposed algorithm, various experiments are performed for CBNU and NLPR DB datasets. From these, we obtained better classification rates in comparison with the result produced by previous methods.

• Journal of Institute of Control, Robotics and Systems
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• v.10 no.9
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• pp.833-839
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• 2004

This paper proposes a method that minimizes the consumed energy by searching the optimal locations of the mass centers of links composing of a biped robot using Real-Coded Genetic Algorithm. Generally, in order to utilize optimization algorithms, the system model and design variables must be defined. Firstly, the proposed model is a 6-DOF biped robot composed of seven links, since many of the essential characteristics of the human walking motion can be captured with a seven-link planar biped walking in the saggital plane. Next, Fourth order polynomials are used for basis functions to approximate the walking gait. The coefficients of the fourth order polynomials are defined as design variables. In order to use the method generating the optimal gait trajectory by searching the locations of mass centers of links, three variables are added to the total number of design variables. Real-Coded GA is used for optimization algorithm by reason of many advantages. Simulations and the comparison of three methods to generate gait trajectories including the GCIPM were performed. They show that the proposed method can decrease the consumed energy remarkably and be applied during the design phase of a robot actually.

• Journal of KIISE:Software and Applications
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• v.36 no.2
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• pp.131-143
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• 2009

Based on the fact that a human being walks naturally and stably with consuming a minimum energy, this paper proposes a new method of generating a natural gait of 5-link biped robot like human by analyzing a COG (Center Of Gravity) trajectory of human's gait. In order to generate a natural gait pattern for 5-link biped robot, it considers the COG trajectory measured from human's gait images on the sagittal and frontal plane. Although the human and 5-link biped robot are similar in the side of the kinematical structure, numbers of their DOFs(Degree Of Freedom) are different. Therefore, torques of the human's joints cannot are applied to robot's ones directly. In this paper, the proposed method generates the gait pattern of the 5-link biped robot from the GA algorithm which utilize human's ZMP trajectory and torques of all joints. Since the gait pattern of the 5-link biped robot model is generated from human's ones, the proposed method creates the natural gait pattern of the biped robot that minimizes an energy consumption like human. In the side of visuality and energy efficiency, the superiority of the proposed method have been improved by comparative experiments with a general method that uses a inverse kinematics.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.05a
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• pp.957-958
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• 2010

• Korean Journal of Applied Biomechanics
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• v.16 no.2
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• pp.85-95
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• 2006

The purpose of this study of which 10 University students in their twenties are the objects was to examine the causal differences of kinematic and electromyography during power walking and normal gait. We came to the following conclusions. 1) It took less time to stance phase, swing phase and whole gait time during power walking compared with normal gait. 2) During power walking, the step length and step length and lower limb length are longer than that of normal gait. 3) During power walking, ankle joint angle became more plantar flexed at LIC and RTO, knee joint angle become more flexed, so did hip joint angle at LIC and RTO. Besides during power walking the shoulder joint angle movement was bigger and elbow joint angle was more flexed as the trait of power walking. 4) During power walking, through out the phase the muscle activity of all muscle was higher expecially the muscle activity of Biceps brachii, gastrocnemius medialis, gastrocnemius lateralis, Soleus was higher. Therefore during power walking, one's scope of activity and muscle activity is relatively higher than those of normal gait, so power walking helps one strengthen muscular power and energy metabolism. This will be useful information for those who are interested in diet and well-being.

• Journal of the Korean Institute of Intelligent Systems
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• v.22 no.5
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• pp.617-623
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• 2012

In this paper, we propose a gait generation method for a quadruped robot to walk efficiently on the slope, which uses the waist joint of a quadruped robot. We derive the kinematic model of a quadruped robot with waist joint using the Denavit-Hartenberg representation method and the algebraic method. In addition, the gaits are generated based on the wave gait. In the proposed gait generation method, first in order to alleviate the mechanical restriction and the reduction of the stride, we determine the appropriate waist joint angle according to the slope degree, and then decide the location of the tiptoe of a quadruped robot by exploring the workspace. Finally, through computer simulations, we verify the effectiveness and applicability of the proposed method.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.1500-1503
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• 2003

One of the main goals in the rehabilitation of SCI patients is to enable the patient to stand and walk themselves. We are developing high-thrust powered gait orthosis(PGO) that use air muscle actuator(shadow robot Co., UK) to be assisted gait and rehabilitation purposes of them. We made of PD controller and measured hip joint angle by its load and the pressure to control air muscle of PGO. As a results, maximum flexion angle of hip joint is $20^{\circ}$, and angular velocity is 30.4${\pm}2.5^{\circ}/sec$, and then delay time of system was average 0.62${\pm}$0.03s. As the hip flexion angle and the pelvic angle is decreased during the gait with PGO, the patient can walk faster. By using the PGO, the energy consumption can also be decreased. therefore, the proposed PGO can be a very useful assitive device for the paraplegics to walk.

• Physical Therapy Korea
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• v.7 no.2
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• pp.55-65
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• 2000

The purpose of this study was to compare the effects of anterior walker and posterior walker on gait parameters and body alignment of children with cerebral palsy. The intraclass correlation coefficient was .99 for intertester reliability. Intratester reliability was between .96 and .99. The use of posterior walker increased gait velocity and facilitated more upright posture. The measurement of joint angle program was found to be reliable to measure range of motion. This study has a limitation of generalizing the results to all children with cerebral palsy. Research is required to investigate the effect of posterior walker on energy efficiency.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.3
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• pp.1266-1273
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• 2013

The purpose of this study was to analysis the effect of form of outsole - complex function double rocker sole(CDR) vs. negative-heel rocker sole (NR) - on energy consumption and heart rate intensity during gait. 11 women, who had no medical history on musculoskeletal disease and surgery within 3 years prior to study, were participated. The walking energy cost per time (WECt) during 35minutes, heart rate intensity, and total calorie consumption were compared by using pair t-test. The WECt and total calorie consumption were found to be significantly higher(p<.05) in CDR than NR. However, there was no difference in HRi. Based on the present study, CDR shoe may have significant implications in shoe prescription for people who want to increase energy consumption.