• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.401-401
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• 2000

A mobile manipulator-a serial connection of a mobile robot and a task robot is redundant by itself. Using its redundant freedom, a mobile manipulator can move in various modes, and perform dexterous tasks. An interesting question,

• Journal of the Ergonomics Society of Korea
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• v.8 no.2
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• pp.19-26
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• 1989

This study, as a part of integrated human-robot ergonomics, improves the robot motion control on the robot task in the TOES/WCS whose purpose is improving the teaching task constructed in the previous study. First, the updated combined fuzzy process using a new membership function with Weber's law is constructed for the purpose of coordinate reading of the end points in the macro motion control. Second, an algorithm using the geometric analysis is desinged in order to calculate position values and posture values of the robot joints. Third, the MGSLM method is designed to remove unnecessary the robot motion control caused by the GSLM method in the micro motion control. Consequently, proposed methods in this study lessen burdcn of a human of an improvement of the robot motion control and reduce the teaching time of a human operator and inaccuracy of the teaching task, which contribute to the integrated human-robot ergonomics.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.243-246
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• 1996

Modular robot manipulator is a robotic system assembled from discrete joints and links into one of many possible manipulator configurations. This paper describes the design method of newly developed modular robot manipulator and the methodology of a task based reconfiguration of it. New locking mechanism is proposed and it provides quick coupling and decoupling. A parallel connection method is devised and it makes modular robot manipulator working well and the number of components on each module reduced. To automatically determine a sufficient or optimal arrangement of the modules for a given task, we also devise an algorithm that automatically generates forward and inverse manipulator kinematics, and we propose an algorithm which maps task specifications to the optimized manipulator configurations. Efficient genetic algorithms are generated and used to search for a optimal manipulator from task specifications. A few of design examples are shown.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.543-548
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• 2000

In this study, an interactive programming method for robot in electronic part assembly task is proposed. Many of industrial robots are still taught and programmed by a teach pendant. The robot is guided by a human operator to the desired application locations. These motions are recorded and are later edited, within the robotic language using in the robot controller, and play back repetitively to perform robot task. This conventional teaching method is time-consuming and somewhat dangerous. In the proposed method, the operator teaches the desired locations on the image acquired through CCD camera mounted on the robot hand. The robotic language program is automatically generated and downloaded to the robot controller. This teaching process is implemented through an off-line programming software. The OLP is developed for an robotic assembly system used in this study. In order to transform the location on image coordinates into robot coordinates, a calibration process is established. The proposed teaching method is implemented and evaluated on an assembly system for soldering electronic parts on a circuit board. A six-axis articulated robot executes assembly task according to the off-line teaching in the system.

• Journal of the Korea Society of Computer and Information
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• v.13 no.3
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• pp.153-160
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• 2008

One of the most important features of the Mobile Manipulator is redundant freedom. Using it's redundant freedom, a Mobile Manipulator can move in various modes, and perform dexterous motions. In this paper, to improve robot job performance, two robots -mobile robot, task robot- are joined together to perform a job, we studied the optimal position and posture of a Mobile Manipulator to achieve a minimum of movement of each robot joint. Kinematics of mobile robot and task robot is solved. Using the mobility of a Mobile robot, the weight vector of robots is determined. Using the Gradient method, global motion trajectory is minimized, so the job which the Mobile Manipulator performs is optimized. The proposed algorithm is verified with PURL-II which is Mobile Manipulator combined Mobile robot and task robot, and the results are discussed.

• Journal of Institute of Control, Robotics and Systems
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• v.15 no.5
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• pp.538-542
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• 2009

Industrial manipulators have been mostly used in large companies such as automakers and electronics companies. In recent years, however, demands for industrial manipulators from small and medium-sized enterprises are on the increase because of shortage of manpower and high wages. Since these companies cannot hire robot engineers for operation and programming of a robot, intuitive teaching and playback techniques of a robot manipulator should replace the robot programming which requires substantial knowledge of a robot. This paper proposes an intuitive teaching and playback algorithm used in assembly tasks. An operator can directly teach the robot by grasping the end-effector and moving it to the desired point in the teaching phase. The 6 axis force/torque sensor attached to the manipulator end-effector is used to sense the human intention in teaching the robot. After this teaching phase, a robot can track the target position or trajectory accurately in the playback phase. When the robot contacts the environment during the teaching and playback phases, impedance control is conducted to make the contact task stable. Peg-in-hole experiments are selected to validate the proposed algorithm since this task can describe the important features of various assembly tasks which require both accurate position and force control. It is shown that the proposed teaching and playback algorithm provides high positioning accuracy and stable contact tasks.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.180-185
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• 2003

In order to enhance dexterity in execution of robot tasks, a redundant number of degrees-of-freedom (DOF) is adopted for design of robotic mechanisms like robot arms and multi-fingered robot hands. Associated with such redundancy in the number of DOFs relative to the number of physical variables necessary and sufficient for description of a given task, an extra performance index is introduced for controlling such a redundant robot in order to avoid arising of an ill-posed problem of inverse kinematics from the task space to the joint space. This paper shows that such an ill-posedness of DOF redundancy can be resolved in a natural way by using a novel concept named “stability on a manifold”. To show this, two illustrative robot tasks 1) robotic handwriting and 2) control of an object posture via rolling contact by a multi-DOF finger are analyzed in details.

• Journal of Institute of Convergence Technology
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• v.6 no.2
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• pp.9-13
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• 2016

Robot usually requires spline motion to move through multiple knots. In this paper, catmull-rom spline method is applied to the trajectory planning of industrial robot in task space. Centripetal catmull-rom is selected to avoid self-intersection and slow motion which can be occurred in uniform and chordal spline. The method to set two control points are proposed to satisfy velocity conditions of initial and final knots. To optimize robot motion, time scaling method is presented to minimize margin between real robot value and maximum value in velocity and acceleration. The simulation results show that the proposed methods are applied to trajectory planning and robot can follow the planned trajectory while robot motion does not exceed maximum value of velocity and acceleration.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.931-932
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• 2006

This paper proposes a task modeling architecture -.uFlow-.for home service robots that facilitates the developmental process and let developers implement their services with ease and efficiency.

• Journal of the Ergonomics Society of Korea
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• v.18 no.3
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• pp.127-140
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• 1999

In order to apply three-dimensional images to industries, the possibility of realizing three-dimensional images should be ensured and when operating a task using three-dimensional images, the intention of the observer and the result of operation should be precisely related. The aim of this paper is to investigate the task performance of a human operator during operating a robot manipulator using three-dimensional and two-dimensional image displays. From the result of this research, it was found that the accuracy of robot operation in the case of using three-dimensional displays is much higher than in the case of using two-dimensional displays and the adapting time to the operating task using three-dimensional displays is shorter than that using two-dimensional displays. From such results, we concluded that the application of three-dimensional displays, which can closely reflect real environment, to industries is desirable.