• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.51.4-51
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• 2001

In order to comprise a basic closed-loop control system for a field robot it is necessary to detect the piston rod stroke of a hydraulic cylinder. There are mary conventional type sensors which can detect the displacement of cylinders. However, they cannot reveal the original performance normally or the cannot be applied at all where the operating circumstance of cylinders is beyond specifications of sensors. In this paper, an exclusive method for detecting the piston rod stroke is suggested, which adopts a remote detecting technique using optical fiber sensors. Several experiments using the prototype are executed for verifying the effectiveness of the suggested method and the possibility of the accurate detection of stroke.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.57.4-57
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• 2001

Polishing a die that has free-form surfaces is a time-consuming and tedious job, and requires a considerable amount of high-precision skill. Some workers tend to gradually avoid the polishing work because of the poor working conditions caused by dust and noise. In the our previous study, an automatic polishing system was developed to reduce the polishing time and cope with the shortage of skilled workers. And, to operate the polishing robot system from remote sites, communication network was constructed and monitoring programs (a server program and a client program)) were developed. However, to monitor polishing process in remote sites, users have to install monitoring programs in a client PC. Thus, user can only operate the polishibg system ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.132.6-132
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• 2001

This paper aims to derive a mathematical model of the dynamics of handling tasks in field robot which stable grasping and manipulates a rigid object with some dexterity. Firstly, a set of differential equation describing dynamics of the manipulators and object together with geometric constraint of tight area-contacts is formulated by Lagrange equation. Secondly, problems of controlling both the internal force and the rotation angle of the grasped object under the constraints of area-contacts of tight area-contacts are discussed. The effect of geometric constraints of area-contacts on motion of the overall system is analyzed and a method of computer simulation for overall system of differential-algebraic equations is presented. Thirdly, simulation results are shown and the effects of geometric constraints of area-contact is discussed.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.161.2-161
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• 2001

To achieve a cooperative work between human and robot, it is thought helpful to estimate the states of human mind, which originates his behavior. In this paper, human mind was considered to modify instinctive desires according to the conditions of external world surrounding the instinct. A simple human mind model was designed so that it finds a balance between instinctive desire and restriction from the external world. The external world is divided into three sub-worlds like subject´s whole body, its partner and concerned periphery. Proposed mind model has three-layers construction. Each of the layer tries to find a balance between desire and restriction from external world. In each layer, the role of finding the balance was expressed by an identical optimal control minimizing a performance index function of quadratic form with a weight factor, which is rearranged and named ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.168.4-168
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• 2001

A great many species of fish congregate in schools, reducing the risk of being eaten by predators and giving one of the considerable survival advantages for fishes. Such a fish school is self-organized only due to individual behaviors for matching the speed and direction with the neighboring fishes. It is interesting to simulate these fish school by small robots, because we can understand how the group structure emerges from the interaction among neighboring individuals. We use a nice simulator for Khepera robot presented by Oliver Michel. It is shown that the Khepera simulator is easily applied to fish school due to the algorithm introduced by I Aoki. The simulator includes sensor noise so appropriately that the simulator can be transferred easily to the real environment. The results of simulation are given as follows: (1) The stability as a group is shown by plotting mean deviations from the center of group ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.104.3-104
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• 2001

This paper develops a control approach to generic formation tasks of multiple mobile robots with inaccurate sensor information. Inaccurate sensor information means that all the robots have only local sensors which cannot accurately measure absolute distances and directions of objects. The control logic is developed considering generic situations in order to adapt to increasing number of robots which participate in the formation. Petri nets are used for modeling and design of the control logic, which can visualize the control models and make it easy to check the states of each robot. Physically homogenous mobile robots are designed and built to evaluate the developed logic. Each robot is equipped with eighteen infrared sensors and a UHF transceiver module. The developed control ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.128.6-128
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• 2001

In this paper, we present a methodology of sensing and control for a robot system designed to be capable of grasping an object and moving it to target point Stereo vision system is employed to determine to depth map which represents the distance from the camera. In stereo vision system we have used a center-referenced projection to represent the discrete match space for stereo correspondence. This center-referenced disparity space contains new occlusion points in addition to the match points which we exploit to create a concise representation of correspondence an occlusion. And from the depth map we find the target object´s pose and position in 3-D space. To find the target object´s pose and position, we use the method of the model-based recognition.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.161.5-161
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• 2001

Robots are required to assist our activities in daily life. In this paper, we focus on arm movement to catch moving object as one of important tasks frequently performed by human. We propose an algorithm which enables a robot to perform human-like arm motion to catch a moving object. First we analyze human hand trajectories and velocity profiles to catch an object. From the experimental results, we extract some characteristics in the process of approaching and following a moving object and confirm that these are necessary to realize human-like motion. We then adopt an instantaneous optimal control method which evaluates the error and energy cost at each sampling step, and design two time-varying weight matrices to introduce human characteristic into robot motion. The matrix concerning the error is defined as a time-increasing ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.178.3-178
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• 2001

This paper is concerned with designing a neural network based navigator that is optimized in a user-defined sense for a mobile robot using ultrasonic sensors to travel to a goal position safely and efficiently without any prior map of the environment. The neural network has a dynamically reconfigurable structure that not only can optimize the weights but also the input sensory connectivity in order to meet any user-defined objective. Therefore, in this research, we can select an optimal subset of sensory inputs that results in the best performance related to both navigation and structural complexity. Further, this research uses the manually trained initial population and the modular neural network to alleviate ...

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.137.4-137
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• 2001

Omni-directional mobile robots have been employed popularly in several application areas. However, the optimal design has not been considered yet. This paper introduces an optimal design methodology for omni-directional mobile robots. Optimal design parameters such as the offset distance and the wheel radius are identified with respect to isotropy. Furthermore, the force transmission ratio and actuator sizing problem are treated. Conclusivel, three cases are compared minimum actuation, two active caster wheel, and three active caster wheel, we claim that the redundantly actuated mobile robot with three active caster wheel has the best performance.