• Journal of Electrical Engineering and Technology
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• v.8 no.4
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• pp.879-888
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• 2013

This paper addresses the vision based local path planning system for obstacle avoidance. To handle the obstacles which exist beyond the field of view (FOV), we propose a Panoramic Environment Map (PEM) using the MDGHM-SIFT algorithm. Moreover, we propose a Complexity Measure (CM) and Fuzzy logic-based Avoidance Motion Selection (FAMS) system to enable a humanoid robot to automatically decide its own direction and walking motion when avoiding an obstacle. The CM provides automation in deciding the direction of avoidance, whereas the FAMS system chooses the avoidance path and walking motion, based on environment conditions such as the size of the obstacle and the available space around it. The proposed system was applied to a humanoid robot that we designed. The results of the experiment show that the proposed method can be effectively applied to decide the avoidance direction and the walking motion of a humanoid robot.

• International Journal of Advanced Culture Technology
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• v.10 no.3
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• pp.371-376
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• 2022

The purpose of this study is to develop a walking assistance system with mobility support and life support functions so that the elderly with reduced physical ability and patients who are uncomfortable when moving can move comfortably indoors and outdoors, and help social life. An obstacle recognition sensor module that can be applied indoors and outdoors is installed on a lightweight walking aid. The purpose of this study is to develop a walking assistance system with mobility support and life support functions so that the elderly with reduced physical ability and patients who are uncomfortable when moving can move comfortably indoors and outdoors, and help social life. An obstacle recognition sensor module that can be applied indoors and outdoors is installed on a lightweight walking aid. It is a system structure of an integrated actuator and brake system that can avoid obstacles in consideration of the safety of the elderly and is easy to install on the device. In this paper, the design of a lightweight walking aid was designed to increase the convenience of the socially disadvantaged and the elderly with reduced exercise ability. In addition, in order to overcome the disadvantage of being inconvenient to use indoors due to the noise and vibration of the motor during operation, an In-Wheel type motor is applied to develop and apply a low noise, low vibration and high efficiency drive system.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.481-484
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• 2016

Jansen mechanism is basic principal of walking robot. Because that mechanism have many link, walking robot can walk like animals. One of the feature is that space is existed between leg of walking robot and ground surface. So, it can walk through the non-uniform ground surface that have obstacle. In this paper, I will suggest design of walking robot that can walk on non-uniform ground surface effectively based on Jansen mechanism.

• Physical Therapy Korea
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• v.22 no.4
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• pp.71-78
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• 2015

Previous studies have investigated stepping over obstacles in treadmill walking training (TWT-OS) and treadmill walking training (TWT) alone for walking capacity not considering real physical activity. As such, we investigated the effects of TWT-OS on physical activity and changes in different levels of physical activity based on community ambulation in stroke patients. Thirty subjects were randomly assigned to either the experimental group or the control group, with 15 and 15 subjects, respectively. However, one subject from the control group was excluded because of inadequate treatment sessions. All subjects underwent routine physical therapy in the form of treadmill walking. The subjects in the experimental group underwent simultaneous training in obstacle-stepping while walking on the treadmill for 30 min/day, five times/week, for four weeks. Subjects were given a three-axis accelerometer to wear at the hip on a belt for one-week pre- and post-training physical activity. Step counts for seven days, average daily step counts, and the average of minutes spent in sedentary, light, and above moderate activity were chosen as outcome measures of physical activity. No significant differences between the groups were found in terms of step counts for seven days, average daily activity, or daily activity spent at sedentary levels after four-week interventions. However, the average daily activity spent at light levels (-42.60 min vs. -6.71 min) was significantly lower in the experimental group than in the controls. Conversely, average daily activity spent at above moderate levels was higher (19.86 min vs. 11.07 min) (p<.05) after adjusting for each baseline value. Significant pre- and post-training differences were found in all variables of the experimental group (p<.05). Thus, TWT-OS could improve physical levels above moderate activity as a community-oriented task more than simple repetitive waking on a treadmill, and it could provide an opportunity for patients ambulatory after stroke to participate in the community again.

• Physical Therapy Korea
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• v.20 no.3
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• pp.9-18
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• 2013

The study aimed to compare the effect of the treadmill walking training combined with obstacle-crossing (TWT-OC) and treadmill walking training (TWT) on the walking function of patients with chronic stroke. 29 subjects volunteered to participate in this study; they were randomly assigned to either TWT-OC group (15 subjects) or TWT group (14 subjects). Subjects from the TWT-OC group underwent a treadmill walking combined with obstacles-crossing for 30 minutes daily, three days a week for four weeks, whereas subjects from the TWT group received only a treadmill walking. The 10 m walk test (10MWT), 6-min walk test (6MWT), berg balance scale (BBS), timed up and go test (TUG), activities-specific balance confidence-Korean version (ABC-K), and walking ability questionnaire (WAQ) were measured before and after the 4-week training. The TWT-OC group showed significantly better functional mobility of walking and balance measured by 6MWT (p<.01), BBS (p<.01), and TUG scores (p<.05) when compared with those of the TWT group. Further, within-group comparison showed significant improvement in all variables (p<.01) except for 10MWT. These findings suggest that the TWT-OC and TWT may be helpful for improving the walking function of patients with chronic stroke, and the TWT-OC has probably more favorable outcomes for chronic stroke, however, further trials with wider range of subjects are warranted for generalization and clinical relevance.

• Journal of Institute of Control, Robotics and Systems
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• v.9 no.12
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• pp.1009-1018
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• 2003

In a park or street, we can see many people Jogging or walking with their dogs chasing their masters. In the previous study, an entertainment robot, CARTRI that imitates the dog's behavior was created. The robot's task was chasing a moving goal that was recognized as the master. The physical structure of the CARTRI robot was three-wheel type locomotion system. The sensor system which could detect the position of the master in the outdoor space, was consists of a signal transmitter which was held by the master and five ultrasonic receivers which were mounted on the robot. In the experiment, the robot could chase a human walking in outdoor space like a park. But it could not avoid obstacles and its behavior was only goal-chasing behavior because of the limit of the sensor system. In this study, an improved RF-ultrasonic sensor system which can detect both goal and obstacle is developed in order to enable the CARTRI robot to carry out various behavior. The sensor system has increased angle resolution by using eight ultrasonic receivers instead of five in the previous study. And it can detect obstacle by using reflective type ultrasonic sensors. The sensor system is designed so that detection of goal and obstacle could be conducted in one sampling period. The Performance of the developed sensor system is evaluated through experiments.

• Journal of the Korean Institute of Intelligent Systems
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• v.15 no.1
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• pp.59-64
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• 2005

In the paper, we propose an intelligent walking algorithm of biped robot on the uneven ground and a posture stabilization algorithm against external forces. At first, the mechanics and the control system of biped robot that can walk on the uneven ground and stand external forces are designed. We propose obstacle hurdling, incline walking. and going-up stairs algorithm by using infrared sensors and FSR sensors. Also, posture stabilization algorithm against external forces is designed using FSR sensors. Infrared sensors ate used to detect the obstacles in the working environment and FSR sensors are used to obtain the ZMP of biped robot. The developed biped robot can be controlled by the remote control system using vision system and RF module. The experimental results show that the biped robot Performs obstacle avoidance, obstacle hurdling, walking on the inclined plane, and going up stairs using the proposed walking and stabilization algorithm.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.531-534
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• 2003

In this paper, the Intelligent Space (iSpace) concept is applied for helping disabled or blind persons in crowded environments such as train stations, or airports. The main contribution of this paper is a general mathematical (fuzzy-neuro) description of obstacle avoidance method (walking habit) of moving objects (human beings) in a limited area scanned by the iSpace. A mobile robot with extended functions is introduced as a Mobile Assistant Robot which is assisted by the iSpace. The Mobile Assistant Robot (MAR) can guide and protect a blind person in a crowded environment with the help of the Intelligent Space. The prototype of the Mobile Assistant Robot and simulations of some basic types of obstacle avoidance method (walking habit) are presented.

• Proceedings of the KIEE Conference
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• 2001.11c
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• pp.304-306
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• 2001

This paper presents the obstacle avoidance of a biped walking robot using GA-Fuzzy algorithm. In the case of our previous studies the surface has been assumed to be flat. For the case of the environment with obstacles, however, the walking robot might be unnatural. Thus, we considered the surface contained obstacles that the robot can pass through. We propose the optimal leg trajectory data-base by using genetic algorithm and optimal leg trajectory movement about obstacles that exist in front of the robot using fuzzy approach. It is shown that the robot can move more naturally on the surface that contains obstacles.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.2
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• pp.169-176
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• 2013

To generate the walking path of a humanoid robot in an unknown environment, the shapes of obstacles around the robot should be detected accurately. However, doing so incurs a very large computational cost. Therefore this study proposes a method to classify the obstacle shape into three types: a shape small enough for the robot to go over, a shape planar enough for the robot foot to make contact with, and an uncertain shape that must be avoided by the robot. To classify the obstacle shape, first, the range and the number of the obstacles is detected. If an obstacle can make contact with the robot foot, the shape of an obstacle is accurately derived. If an obstacle has uncertain shape or small size, the shape of an obstacle is not detected to minimize the computational load. Experimental results show that the proposed algorithm efficiently classifies the shapes of obstacles around the robot in real time with low computational load.