• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.8
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• pp.361-366
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• 2001

This thesis proposes a fuzzy logic cross coupled controller for a multi axis servo system. The overall control system consists of three elements: the axial position controller, the speed controller, and a fuzzy logic cross coupled controller. In conventional multi axis servo system, the motion of each axis is controlled independently without regard to the motion of other axes, in which the contour error, defined as the shortest distance between the desired and actual contours is compensated only by the position error of each axis. This decoupled control approach may result in degraded contouring performance due to such factors as mismatch of axial dynamics and axial loop gains. In practice, such systems contain many uncertainties, Therefore, the multi axis servo system must receive and evaluate the motion of all axes for a better contouring accuracy. Cross coupled controller utilizes all axis position error information simultaneously to produce accurate contours. However the existing cross coupled controllers cannot overcome friction, backlash and parameter variation. Also, since it is difficult to obtain an accurate mathematical model of multi axis system, here we investigate a fuzzy logic cross coupled controller method. Some simulations and experimental results are presented to illustrate the performance of the proposed controller.

• Proceedings of the KIEE Conference
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• 2001.07e
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• pp.58-61
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• 2001

The purpose of this paper is a fuzzy logic controller for XY positioning system. The overall control system consists of three parts, the position controller, the speed controller, the fuzzy logic controller. Precise tracking is achieved by fuzzy logic controller. In practice, such systems contain many uncertainties. Therefore, the XY positioning system must receive and evaluate the motion of all axis for a better contouring accuracy. Cross coupled controller utilizes all axis position error information simultaneously to produce accurate contours. However, the existing Cross coupled controllers cannot overcome friction, backlash and parameter variation. So, we propose a fuzzy logic controller of XY positioning system. Experimental results show that the proposed fuzzy logic controller is effective to improve the contouring accuracy of XY positioning system.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.7
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• pp.313-317
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• 2001

This paper proposed a fuzzy logic cross coupled controller which can enhance the path tracking performance of optically guided AGV(Automated Guided Vehicle). The AGV follows the guide path, it cannot be avoid the deviation from the path due to the inevitable error and the deviation must be corrected. Optically guided AGV used in industrial area is controlled by On-Off controller generally, the experimental AGV has three optical sensors in front body. In this structure, we could not know the leaving distance accurately and steering angle from the guided line, so AGV could not be controlled properly with conventional controller in the case of increasing or decreasing velocity. If we mount additional sensors the AGV, we could know the leaving distance and steering angle from the guided line and proper error compensating methode can be applied. But because cost of sensors are high, the cost of total system is increasing. So, in this paper, to improve the tracking performance of AGV which has the minimum number of sensors and fuzzy logic cross coupled controller is proposed. Some simulations and experimental results are presented to illustrate the performance of the proposed controller.

• Journal of the Institute of Electronics Engineers of Korea SC
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• v.37 no.1
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• pp.10-18
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• 2000

This paper proposes a fuzzy logic cross-coupled controller using a new contouring modeling for a two-axis servo system. The general decoupled control approach may result in degraded contouring performance due to such factors as mismatch of axial dynamics and axial loop gains. In practice, such systems contain many uncertainties. The cross-coupled controller utilizes all axis position error information simultaneously to produce accurate contours. However, the conventional cross-coupled controllers cannot overcome friction, backlash, and parameter variations. Also since, it is difficult to obtain an accurate mathematical model of multi-axis system, here we investigate a fuzzy logic cross-coupled controller of servo system. In addition, new contouring error vector computation method is presented. The experimental results are presented to illustrate the performance of the proposed algorithm.