• 제어로봇시스템학회:학술대회논문집
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• 2005.06a
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• pp.740-745
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• 2005

This study is intended to build a controller of redundant manipulators with the simultaneous abilities of trajectory tracking and obstacle avoidance without any preparations of path planning to achieve full automation even for one production of one kind, while keeping the avoidance ability high and keeping its shape away from object to reduce the possibility that the manipulator crashes to the object. To evaluate the avoidance ability of the intermediate link, we proposed a scalar value of Avoidance Manipulability Shape Index(AMSI), which is independent of the obstacle's shape. On the other hand, the danger to crash to the obstacle is depending on the shape of the obstacle, which could be evaluated by the potential field set around the obstacle. This paper proposes control method of the manipulator's shape based on the AMSI to simultaneously avoid obstacles and keep the avoidance ability high with potential.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.4
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• pp.385-389
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• 2009

This paper deals with the enhancement of the complex potential navigation for wheeled mobile robots. The circle theorem from complex function theory is used to avoid an obstacle, and the enhancement to avoid multiple obstacles is proposed. The limit cycle navigation can be combined for robot to kick the ball to the intentioned direction. Avoiding step and superposing twin vortices can be applied to adjust the direction of robot's trajectory. The proposed method is verified through a set of simulation works, and the feasibilities for the enhancement of complex potential theory are successful.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.11
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• pp.1130-1138
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• 2008

A mobile robot should be designed to navigate with collision avoidance capability in the real world, coping with the changing environment flexibly. In this paper, a novel navigation method is proposed for fast moving mobile robots using limit-cycle characteristics of the 2nd-order nonlinear function. It can be applied to robots in dynamically changing environment such as the robot soccer. By adjusting the radius of the motion circle and the direction of the obstacle avoidance, the mobile robot can avoid the collision with obstacles and move to the destination point. To demonstrate the effectiveness and applicability, it is applied to the robot soccer. Simulations and real experiments ascertain the merits of the proposed method.

• Research in Community and Public Health Nursing
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• v.31 no.3
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• pp.375-383
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• 2020

Purpose: The purpose of this study was to investigate factors influencing care workers' intention of hand hygiene implementation in long-term care hospitals. Methods: A total of 180 care workers working at long-term care hospitals were recruited. Data collection was done from July 22 to September 7, 2018. Results: The significant TPB variables influencing the intention of hand hygiene implementation were perceived behavior control (β=.41, p<.001), normative belief (β=.28, p<.001) and attitude toward behavior (β=.15, p=.014). These factors explain 39% of care workers' intension of implementing hand hygiene in long-term care hospitals. Conclusion: In order to strengthen the commitment of hand hygiene, it is necessary to have a positive attitude toward hand hygiene by eliminating the obstacles to hand hygiene.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.120.4-120
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• 2001

In this paper, a method of generating trajectories in real time for a mobile robot in a dynamic environment is proposed. Specifically, this method is focused on soccer-playing robots that need to calculate trajectories in real time, which are constantly subject to rapidly change as targets and obstacles move. The robots also should move at the fastest available speed, while tracking the generated trajectories. The method proposed in this paper solves the geometric problem of finding a smooth curve that joins two endpoints. To have this solved, we assign five constraints to each endpoint, which are the usual x, y, theta, and curvature as well as the influence of the initial robot velocity on the path. With these five constraints, the path generated can always be physically followed by robot. Through this method, the travel time of the robot over the entire path can b optimized. Therefore it can ...

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.2
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• pp.180-188
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• 1999

The objective of this paper is, based upon the principles of artificial life, to induce emergent behaviors of multiple autonomous mobile robots which complex global intelligence form from simple local interactions. Here, we propose an architecture of neural network learning with reinforcement signals which perceives the neighborhood information and decides the direction and the velocity of movement as mobile robots navigate in a group. As the results of the simulations, the optimum weight is obtained in real time, which not only prevent the collisions between agents and obstacles in the dynamic environment, but also have the mobile robots move and keep in various patterns.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.3
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• pp.217-225
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• 2016

In this paper, we propose an improved path planning method and obstacle avoidance algorithm for two-wheel mobile robots, which can be effectively applied in an environment where obstacles can be represented by circles. Firstly, we briefly introduce the rapidly exploring random tree (RRT) and single polar polynomial (SPP) algorithm. Secondly, we present additional two methods for applying our proposed method. Thirdly, we propose a global path planning, smoothing and obstacle avoidance method that combines the RRT and SPP algorithms. Finally, we present a simulation using our proposed method and check the feasibility. This shows that proposed method is better than existing methods in terms of the optimality of the trajectory and the satisfaction of the kinematic constraints.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.12
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• pp.1246-1253
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• 2009

To be high efficient for a navigation of unmanned ground vehicle, it must be able to distinguish between safe and hazardous regions in its immediate environment. We present an advanced method using laser range finder for building global 2D digital maps that include environment information. Laser range finder is used for mapping of obstacles and driving environment in the 2D laser plane. Rotary encoders are used for localization of UGV. The main contributions of this research are the development of an algorithm for global 2D map building and it will turn a UGV navigation based on map matching into a possibility. In this paper, a map building algorithm will be introduced and an assessment of algorithm reliability is judged at an each environment.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.8
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• pp.794-798
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• 2010

This paper presents a new obstacle-avoidance method for mobile robots. This approach, called the FEB (Fast Elastic Band) method, has been developed and successfully tested on the experimental mobile robot PHOPE-1S. The FEB method eliminates the shortcomings of the elastic band method previously introduced, yet retains all the advantages of its predecessor. The FEB algorithm is computationally efficient, and it allows continuous and fast motion of the mobile robot without stopping for obstacles. The FEB-controlled mobile robot traverses very densely cluttered obstacle courses and is able to pass through narrow openings or narrow corridors without oscillations. The results of the simulation and experiment have verified the validity of the proposed method.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.33B no.12
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• pp.1-12
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• 1996

A new local path planning algorithm using DPH (distance profile histogram) is suggested in this paper. The proposed method makes a grid type world map using distance values from multiple ultrasonic sensors and genrates local points through which the mobile robot can avoid obstcles safely. The DPH (distance profile historgram) represents geometrical arrangement of obstacles around the robot in the local polar coordinate system which is assumed to be atached to the robot. To control robot's navigation, a three-layered control structure is adopted. The proposed local path planning algorithm is placed on the top level. And a point-to-point translation controller takes the middle level. The bottom level consists of a velcoity servo and sonar driver modules which take charge of driving physical hardwares. The validity of the propsoed method is demonstated through several experiments.