• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.5
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• pp.622-628
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• 2009

A proper walking pattern is to be assigned for a walk of multi-legged robots. For the purpose of identifying a good walking pattern for multi-legged robots, this paper consider a simple model of quadruped robotic walking and analyze its walking balance based on the centroid of foot polygons formed in every step. A performance index to estimate the walking balance is also proposed. Simulation studies show that the centroid trajectory of foot polygons and the walking balance in a common quadruped walking are different according to the walking pattern employed. Based on the walking balance index and a bio-mimetic aspect, a useful walking pattern for quadruped robots is finally addressed.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.3
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• pp.353-358
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• 2011

This paper presents a virtual-legged walking model for bipedal robots and analyzes its fundamental RPY(Roll, Pitch, and Yaw) motion effects by simulation. For the purpose of identifying the motion effects of the bipedal walking, we assign some arbitrary trajectories both at the center of mass and at the center of pressure of the robot based on human walking. And then we verify the major moments to the roll, pitch, and yaw directions of the robot. As a result, it is shown that those motions are natural in the process of bipedal walking and they are deeply dependent on the step distance, the vertical level of the center of mass, and the acceleration of the robot. The importance of trajectory planning for the footstep location during a bipedal walking is finally addressed in terms of balance.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.11 no.2
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• pp.115-124
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• 2017

This study was to develop the balance insole system for detecting and improving the muscle imbalance of left and right side in lower limbs. We were to verify the validation of balance insole system by analyzing the strategy of muscular activities and foot pressure according to sound feedback. We developed the balance insole based FSR sensor modules for estimating the muscle imbalance using detecting foot pressure. The insole system was FPCB have 8-spot FSR sensor with sensitivity range of 64-level. The participants were twenty peoples who have muscle strength differences in left and right legs over 20%. We measured the muscular activity and foot pressure of left and right side of lower limbs in various gait environment for verifying the improvement effect of muscle imbalance according to sound feedback. They performed gait in slope at 0, 5, 10, 15% and velocity at 3, 4, 5km/h. The result showed that the level of muscle imbalance reduced within 30% for sound feedback of balance insole system contrast to high level of muscle imbalance at 169.9~246.8% during normal gait for increasing slope and velocity. This study found the validation of balance insole system with sound feedback stimulus. Also, we thought that it is necessary to research on the sensitivity of foot area, detection of muscle imbalance and processing algorithm of correction threshold spot.

• Journal of the Korean Institute of Intelligent Systems
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• v.21 no.6
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• pp.673-678
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• 2011

This paper analyzes the standing balance of four-legged robots which are useful for delivering objects or investigating of information. For this, we specify an effective model of general four-legged robots and propose a boundary condition based on the standing stability of the four-legged walking. To verify such a standing balance, we consider some exemplary free motions at the standing mode of the robot and discuss on the robot's balance margin. The analysis specified in this paper will be applicable for effective balancing control of various quadruped robotic walking.

• Journal of Korean Medicine Rehabilitation
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• v.24 no.3
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• pp.149-155
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• 2014

Objectives This study was designed to investigate the correlation between the difference of pelvic height and difference of gait balance. Methods 62 cases of patients who received treatment from January 2011 to March 2014 for abnormal postures were analyzed. Their difference of pelvic height were estimated by whole spine X-ray analysis and gait balance were estimated by Treadmill Gait Analysis system. The data were analyzed to find out correlation between difference of pelvic height and difference of gait balance, and correlation between the position of pelvic tilt and gait balance higher side. Pearson correlation and Chi-square analysis were used. Results Pelvic height heigher side were more left than right side, and gait balance higher side were also more left than right side. Difference of pelvic height and difference of gait balance had a positive linear relationship, but there was no significant correlation. The position of pelvic tilt had significant correlation with gait balance higher side. Conclusions The position of pelvic tilt had significant correlation with gait balance higher side and difference of pelvic height had no significant correlation with difference of gait balance.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.1
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• pp.45-52
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• 2016

PURPOSE: The purpose of this study was to determine the effects of balance training on balance pad and sand on balance and gait ability in stroke patients. METHODS: Sixty stroke patients were divided into a Balance Pad group(BPG, N = 20), a Sand group (SG, N = 20) and a Hard Ground group (HGG, N = 20) randomly. The subjects in the Hard Ground group stood in a comfortable position, faced a therapist, then threw a Swiss ball back and forth. They then performed balance training in which they raised and lowered their ankles while facing forward or moved objects from one table to another. The BPG performed same tasks in HGG, on an unstable surface using a balance pad. The SG performed same tasks on sand ground. All groups received training 30min per day, five times per week, for eight weeks. RESULTS: After intervention, all groups showed significant increases balance and gait components. And the BPG and the SG showed significant increase in weight distribution rate, Sway length and BBS compared with the HGG, but there was no significant difference in Cadence, Stride length among three groups. CONCLUSION: According to the results of this study, balance training on unstable surface using balance pad and sand was more effective in improving balance in stroke patients.

• Journal of the Korean Association of Geographic Information Studies
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• v.21 no.4
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• pp.26-49
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• 2018

The purpose of this study was to verify the reliability of the solar radiation model and discuss its applicability to the urban area of Seoul for summer heat stress mitigation. We extended the study area closer to the city scale and enhanced the spatial resolution sufficiently to determine pedestrian-level urban radiance. The domain was a $4km^2$ residential area with high-rise building sites. Radiance modelling (SOLWEIG) was performed with LiDAR (Light Detection and Ranging)-based detailed geomorphological land cover shape. The radiance model was evaluated using surface energy balance (SEB) observations. The model showed the highest accuracy on a clear day in summer. When the mean radiation temperature (MRT) was simulated, the highest value was for a low-rise building area and road surface with a low shadow effect. On the other hand, for high-rise buildings and vegetated areas, the effect of shadows was large and showed a relatively low value of mean radiation temperature. The method proposed in this study exhibits high reliability for the management of heat stress in urban areas at pedestrian height. It is applicable for many urban micro-climate management functions related to natural and artificial urban settings; for example, when a new urban infrastructure is planned.

• Journal of Industrial Convergence
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• v.18 no.5
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• pp.42-53
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• 2020

This study approached the elderly in Korea with a systematic review to find out the effect of virtual reality program arbitration on balance, which the evidence for the virtual reality program is provided. Total of 94 papers were searched through the database Nuri Media (DBpia), Scholarship (earticle), Korean Studies Information (KISS), National Digital Science Library (NDSL), the Korea Educational Research and Information Service (RISS), Kyobo Book Scholar (RISS), and Hakjisa New Thesis on Literature Selection using PRISMA flow-chart from January 2005 to May 2020 based on the final literature selection process and analysis. The quality level of the literature was found to be three volumes (50.0%) of the base level I, one (16.7%) of the II, and two of the III (33.3%). The most common type of virtual reality program was Wii-fit balance of 4 (66.7%), and the effect of virtual reality program arbitration was significant overall through evaluation tools for balance and walking ability. This is expected to effectively apply the virtual reality program to the elderly. In addition, since clinical application basis has been provided, further studies applying various virtual reality program interventions need to be addressed.