• Journal of Institute of Control, Robotics and Systems
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• v.22 no.10
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• pp.826-832
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• 2016

A two-wheeled balancing mobile robot (TWBMR) has the characteristics of both nonlinear and underactuated system. In this paper, the disturbances acting on a TWBMR are classified into body disturbance and wheel disturbance. Additionally, we describe a nonlinear disturbance observer, which is suitable as a single input multi-output (SIMO) system for the longitudinal motion of TWBMR. Finally, we propose a reasonable disturbance compensation technique that combines the indirect reference input of equilibrium point and the direct torque compensation input. Simulations and experimental results show that the proposed disturbance compensation method is an effective way to achieve robust postural stability, specifically on inclined terrains.

• Journal of Industrial Technology
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• v.13
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• pp.19-24
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• 1993

Compensation of temperature is very important to make high precision load cell. In this study, we developed a new type load cell. The structure of the load cell has four strain gauges on single side of the load cell beam. Also a new temperature compensation method was proposed and these characteristics were better than previous one. This study will offer application to other type of load cell and another sensors.

• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1006-1008
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• 1998

This paper describes the possible undesier-able side effects that thyristor controlled compensation may have upon in several relays. This process consisted of calculating line conditions for each of the fault, compensation and loading levels. In some cases their effectiveness at coordinating compensated lines is lost, as they no longer can always accurately determine "distances" to faults.

• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1333-1335
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• 2005

STATCOM has many advantages rather tan SVC at a view point of a continuous controllability of reactive power and response time of reactive power compensation In this paper, 30kVA STATCOM for compensation of low voltage industrial loads is designed and its operation characteristics is analyzed and verified by simulation.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.10a
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• pp.214-219
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• 2001

One of the major limitations of productivity and quality in metal cutting is the machining accuracy of machine tools. The machining accuracy is affected by geometric errors, thermally-induced errors, and the deterioration of the machine tools. Geometric and thermal errors of machine tools should be measured and compensated to manufacture high quality products. In metal cutting, the machining accuracy is more affected by thermal errors than by geometric errors. In this study, the compensation device and temperature-based algorithm have been presented in order to compensate thermal error of machine tools under the real-time. The thermal error is modeled by means of angularity errors of a column and thermal drift error of the spindle unit which are measured by the touch probe unit with a star type styluses, a designed spherical ball artifact, and five gap sensors. In order to compensate thermal characteristics under several operating conditions, experiments performed with five gap sensors and manufactured compensation device on the horizontal machining center.

• Proceedings of the IEEK Conference
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• 2005.11a
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• pp.853-856
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• 2005

we proposed the optimized conditions of the uniaxial and biaxial compensation films to suppress the light leakage to improve viewing angle characteristics. Compared with conventional OCB mode, the maximum transmittance is increased about 30% and the minimum transmittance is slightly decreased. From here results, we can about OCB mode with wide viewing angle and high contrast ratio.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 1993.06a
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• pp.845-848
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• 1993

This paper proposes a design method of fuzzy phase-lead compensator and its self-learning by neural network. The main feature of the fuzzy phase-lead compensator is to have parameters for effectively compensating phase characteristics of control systems. An important theorem which is related to phase-lead compensation is derived by introducing concept of frequency characteristics. We propose a design procedure of fuzzy phase-lead compensators for linear controlled objects. Furthermore, we realize a neuro-fuzzy compensator for unknown or nonlinear controlled objects by using Widrow-Hoff learning rule.

• Journal of the Korean Society for Precision Engineering
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• v.19 no.5
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• pp.13-18
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• 2002

• Journal of the Korean Society for Precision Engineering
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• v.19 no.5
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• pp.7-12
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• 2002

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.219-223
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• 2000

In this paper a new current controller with dead time compensation for small time constant PMSM is proposed. Precise analysis on voltage distortion by dead time and device characteristics is presented. Simulation results are presented to demonstrated the validity of the proposed method.