• Journal of Institute of Control, Robotics and Systems
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• v.18 no.11
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• pp.989-996
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• 2012

The purpose of this paper is to analyze GPS (Global Positioning System) satellite orbital mechanics, and then to propose a novel long-term GPS satellite orbit prediction scheme including virtual planet perturbation. The GPS orbital information is a necessary prerequisite to pinpointing the location of a GPS receiver. When a GPS receiver has been shut down for a long time, however, the time needed to fix it before its reuse is too long due to the long-standing GPS orbital information. To overcome this problem, the GPS orbital mechanics was studied, such as Newton's equation of motion for the GPS satellite, including the non-spherical Earth effect, the luni-solar attraction, and residual perturbations. The residual perturbations are modeled as a virtual planet using the least-square algorithm for a moment. Through the modeling of the virtual planet with the aforementioned orbital mechanics, a novel GPS orbit prediction scheme is proposed. The numerical results showed that the prediction error was dramatically reduced after the inclusion of virtual planet perturbation.

• Journal of Institute of Control, Robotics and Systems
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• v.16 no.4
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• pp.391-395
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• 2010

In our paper, we propose an asymmetric single-tracked wheel system, and describe its structure and the method for maintaining the length of a transformable track system. And the method is reducing the gap of lengths. Therefore, we propose an efficient structure for transforming and explain motions with kinematics. Our transformable shape single-tracked mobile system has an advantage to overcome an obstacle or stairs by the variable arms in the single unity track system. But we will make the variable shape of tracked system get a drive that has a force to stand against a wall. In this case, we can consider this system to a rigid body and have a notice that this single tracked system is able to get vary shape with the variable arm angle. Considering forces balance along x-axis and y-axis, and moments balance around the center of the mass we have. If this rigid body is standing against a wall and doesn't put in motion, the force of flat ground and the rigid body sets an equal by a friction. In the same way, the force of a wall and the rigid sets an equal by a friction.

• Journal of Ocean Engineering and Technology
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• v.27 no.2
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• pp.80-86
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• 2013

KIOST developed a deep-sea mining robot called "MineRo" to collect manganese nodules in 2007. MineRo operates on flat ground. SMS (seafloor massive sulfide) deposits are shaped like undulating mountains. This paper deals with a numerical analysis model of a mining robot for SMS deposits. The mining robot consists of a tracked vehicle, chassis structure with a turntable, boom arm with 2 articulations, excavation tool, discharging unit, hydro-electric system, and sensing-and-monitoring system. In order to compare and analyze the dynamic responses of the driving mechanism, various tracked vehicles are modeled using commercial software. Straight driving simulations are conducted under undulating ground conditions. A conceptual design of a mining robot with four track systems for SMS deposits is modeled on the basis of these results.

• Proceedings of the Korea Society for Industrial Systems Conference
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• 2006.05a
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• pp.211-217
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• 2006

The learning control develops controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work, the authors presented an iterative precision of linear decentralized learning control based on p-integrated learning method for the vertical dynamic multiple systems. This paper develops an indirect decentralized learning control based on adaptive control method. The original motivation of the teaming control field was teaming in robots doing repetitive tasks such as on an assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the nominal trajectory, and using the usual robot controllers that are decentralized, treating each link as if it is independent of any coupling with other links. Error wave propagation method will show up in the numerical simulation for five-bar linkage as a vertical dynamic robot. The methods of learning system are shown up for the iterative precision of each link at each time step in repetition domain. Those can be helped to apply to the vertical multiple dynamic systems for precision quality assurance in the industrial robots and medical equipments.

• Journal of Korea Society of Industrial Information Systems
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• v.11 no.2
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• pp.40-47
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• 2006

The learning control develops controllers that learn to improve their performance at executing a given task, based on experience performing this specific task. In a previous work the authors presented an iterative precision of linear decentralized learning control based on p-integrated teaming method for the vertical dynamic multiple systems. This paper develops an indirect decentralized learning control based on adaptive control method. The original motivation of the loaming control field was learning in robots doing repetitive tasks such as on a]1 assembly line. This paper starts with decentralized discrete time systems, and progresses to the robot application, modeling the robot as a time varying linear system in the neighborhood of the nominal trajectory, and using the usual robot controllers that are decentralized, treating each link as if it is independent of any coupling with other links. Error wave propagation method will show up in the numerical simulation for five-bar linkage as a vertical dynamic robot. The methods of learning system are shown up for the iterative precision of each link at each time step in repetition domain. Those can be helped to apply to the vertical multiple dynamic systems for precision quality assurance in the industrial robots and medical equipments.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.30 no.4
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• pp.329-340
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• 1994

This paper presents a dynamic compensation methodology for robust trajectory tracking control of uncertain robot manipulators. To improve tracking performance of the system, a full model-based feedforward compensation with continuous VS-type robust control is developed in this paper(i.e,. robust decentralized adaptive control scheme). Since possible bounds of uncertainties are unknown, the adaptive bounds of the robust control is used to directly estimate the uncertainty bounds(instead of estimating manipulator parameters as in centralized adaptive control0. The global stability and robustness issues of the proposed control algorithm have been investigated extensively and rigorously via a Lyapunov method. The presented control algorithm guarantees that all system responses are uniformly ultimately bounded. Thus, it is shown that the control system is evaluated to be highly robust with respect to significant uncertainties.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.4
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• pp.817-823
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• 2009

This paper proposes a robust method for mapping of a caterpillar-type mobile robot which inherently has uncertainty in its modeling by compensating for the estimated pose error of the robot. In general, a caterpillar type robot is difficult to model, which results in inaccuracy in Simultaneous Localization And Mapping(SLAM). To enhance the robustness of the SLAM for a caterpillar-type mobile robot, we factorize the SLAM posterior, where we used particle filter to estimate the position of the robot and Extended Kalman Filter(EKF) to map the environment. The simulation results show the effectiveness and robustness of the proposed method for mapping.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.304-306
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• 1993

In this paper, the authors show a link between a heuristic controller used in industry and a theoretical generalized controller. First, we clarify the internal structure of the generalized two-degree-of-freedom controller which yields a link between the theoretical researches and the practical applications. Secondly, we indicate how to blend identification and control together without any modification of the controller. This is in fact the problem of closed-loop identification. Thirdly, we propose a design technique of a free parameter taking into account a robust stability based on the information obtained from the identification. Finally, we apply the proposed algorithm to trajectory control of DD robot.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1995.03a
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• pp.131-144
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• 1995

This paper presetns modifications of a hydraulic shovel to robotize, and we derive a dynamic model of the hydraulic shovel arms,and hydraulic analysis are discussed . Then , our purpose is making to imitate a target railroad line of the grinder position by the PID control. Moreover, to determine the gains of the PId controller, we referenced the Ziegler and Nichols' method. In this paper, we demonstrated that the PID control is available for system. These results indicated the possibility of practical use fo the deburring robot with the hydraulic shovel.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2393-2395
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• 2001

The mobile robot is used as an instrument of transportation in automated plant. But the greater part of the moving method is the wheel-type. The wheel-type robot is easier control than the track-type, However the track-type is better than the wheel-type in bad landform(bend landform, an incline plane, stairs). In this paper, we propose the navigation algorithm of track-type robot in order to improve a defect of wheel-type. We experiment in bend landfrom and even ground to differentiate the navigation method. To estimate robot pose, we use the 80196 in a close distance and the vision-board in a long distance. Each data is managed in main PC and then the part of managing correspond to every sensor. We also use twelve supersonic wave-sensors to recognize external surroundings. As the result of experiment, we analyze the algorithm of control and make possible surroundings-adaptation.