• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.594-596
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• 1987

In this study, a method of obtaining reasonably large and constant torque at high speed is given in order to improve the performance of the open loop controlled step motor system using the current source, thus resulting in high performance compared to the conventional current limiting using resistor and chopper.

• 제어로봇시스템학회논문지
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• 제18권3호
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• pp.251-257
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• 2012

Unmanned ground vehicles have important military, reconnaissance, and materials handling application. Many of these applications require the UGVs to move at high speeds through uneven, natural terrain with various compositions and physical parameters. This paper presents a framework for high speed autonomous navigation based on the integrated real time traversability. Specifically, the proposed system performs real-time dynamic simulation and calculate maximum traversing velocity guaranteeing safe motion over rough terrain. The architecture of autonomous navigation is firstly presented for high-speed autonomous navigation. Then, the integrated real time traversability, which is composed of initial velocity profiling step, dynamic analysis step, road classification step and stable velocity profiling step, is introduced. Experimental results are presented that demonstrate the method for a $6{\times}6$ autonomous vehicle moving on flat terrain with bump.

• 한국위성정보통신학회논문지
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• 제11권1호
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• pp.46-50
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• 2016

The adaptive power control of Code Division Multiple Access (CDMA) systems for communications between User Equipments (UEs) with a link-budget based Signal-to-Interference Ratio (SIR) estimate which has distance information is applied to three inner loop power control algorithms. The speed estimation performances of these algorithms with their consecutive Transmit-Power-Control (TPC) ratios are compared to each other, and it is concluded that the speed can be estimated using the TPC ratio information of Consecutive TPC Ratio Step-size Closed Loop Power Control (CS-CLPC) and Fixed Step-size Power Control (FSPC).

• 한국정보통신학회논문지
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• 제2권3호
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• pp.295-302
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• 1998

본 논문에서는 한계계단 응답특성을 이용하여 영구자석헝 동기전동기의 속도 제어계에 대한 새로운 자동동조 PI(Proportional Integral) 제어기를 설계하였다. 과도응답 기간동안 소위 한계입력이라고 하는 계단입력을 인가하여 Pㅑ 제어기의 자동동조를 위한 정보를 얻기 위한 기법을 제안한다. 시스템 파라메터 추정과 동시에 속도제어가 온라인으로 이루어지는데, 이것은 시스템의 불확실성에도 불구하고 한계입력에 의해서 얻어진 시스템 파라메터 정보가 연속적으로 PI 제어기에 적용될 수 있다는 것이다. 제안된 자동동조 알고리즘은 단조증가 계단응답 특성을 갖는 영구 자석형 동기전동기의 속도제어에 대한 시뮬레이션과 실험결과를 통하여 그 유효함을 확인하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.448-455
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• 1996

In this study, to reduce vibration of step motor we use Microstep control. Microstep control of stepmotor is usually thought of as an extension of conventional stepmotor control technology. The essence ofmicro stepping is that we divide the full step of a stepmotor into a number of substep called microstep and cause the stepmotor to move through a substep per input pulse. In ideal case, bycontrolling the individual phase currents of a two-phase step motor sinusoidally we can get uniform torque and step angles. But due to the monlinear characteristics of the step motor, we need to compensate current waveform to improve the overall smoothness of the conventional micro stepping system. We implement digital Pulse Width Modulation(PWM) driver to drive step motor and microphone was used for detecting vibration. Driver enables speed change automatically byincreasing or decreasing micro stepping ratio which we call Automatic Switching on the Fly. To compensate the torque harmonics, Neural Networks is applied to the system and we foundcompensated optimal input current waveform. Finally we can get smooth motion of step motor in a wide range of motor speed.

• 한국정밀공학회지
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• 제14권5호
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• pp.118-127
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• 1997

In this study, We use microstep control to reduce vibration of step motor. Microstep control of step motor is usually thought of as an extension of conventional step motor control technology. The essence of micro stepping is that we divide the full step of a step motor into a number of substep called microstep and cause the stepmotor to move through a substep per input pulse. In ideal case, by controlling the individual phase currents of a two-phase step motor sinusoidally we can get uniform torque and step angle. But due to the nonlinear characteristics of the step motor, we need to compensate current waveform to improve the over-all smoothness of the conventional micro stepping system. We implement digital Pulse Width Modul- ation (PWM) driver to drive step motor and microphone was used for detecting vibration. Driver enables speed change automatically by increasing or decreasing micro stepping ratio which we call Automatic Switching on the Fly. To compensate the torque harmonics, neural network is applied to the system and we found compensated optimal input current waveform. Finally we can get smooth motion of step motor in a wide range of motor speed.

• Journal of Biosystems Engineering
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• 제11권1호
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• pp.17-23
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• 1986

Speed control of kerosene engine by the combination of a manual throttle and centrifugal weight type governor is not adequate for evaluating energy requirements in laboratory and field performance tests. This paper describes an engine speed control system. This system consists of Apple-II microcomputer, step motor set to the throttle shaft directly, step motor driving and interfacing circuit, engine performance data acquisition system for measuring load, speed and time and potentiometer as speed adjustor. The performance of this system was successful in maintaining engine speed within ${\pm}37$ rpm of reference speed indicated by computer and potentiometer.

• 대한전기학회논문지:시스템및제어부문D
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• 제53권4호
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• pp.212-220
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• 2004

The present DC Motor or STEP Motor have been used in electronic work and products. There are many papers that let those Motor improved more conveniently in controlling and measuring those than before. By controlling and measuring those, the convenience of users and the functions of products can be improved. In addition, the responding speed of whole system can be increased by improving it of controlling and measuring. Therefore it is necessary that we develop motor motion application. Because of this necessity, neural networks was used to improve the responding speed of controlling and measuring, and a new application was developed for the convenience of users. This paper showed that efficiency of controlling methodology by neural-network is superior to others in correctness and speed. We are intend to verify its practical usefulness though experimentations.

• 대한전자공학회논문지
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• 제27권6호
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• pp.871-878
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• 1990

The control method which electrically subdivides 1 step(1.8\ulcornerstep) of a PM step motor into 64 micro-step (0.028\ulcornerstep) is realized using micro-step algorithm on the basis of the look up table method and the position and velocity control using Z-80 microprocessor is also realized. With micro-stepping. The resolution of the system is improved, also by micro-step control of driving-current of the step motro, which is followed by the increase of micro-step subdivision-coefficient, the precise position and velocity control of step-motor can be realized and the stabilization of the system is improved.

• Journal of Power Electronics
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• 제11권4호
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• pp.449-455
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• 2011

Electric drive vehicles (EDV) have received much attention recently because of their environmental and energy benefits. In an EDV, the motor drive system directly influences the performance of the propulsion system. However, the available DC voltage is limited, which limits the maximum speed of the motors. At high speeds, the inverter voltage increases if the square wave (SW) voltage (six-step operation) is used. Although conventional direct torque control (DTC) has several advantages, it cannot work in the six-step mode required in high-speed applications. In this paper, a single-mode seamless DTC for AC motors is proposed. In this scheme, the trajectory of the reference flux changes continuously between circular and hexagonal paths. Therefore, the armature voltage changes smoothly from a high-frequency switching pattern to a square wave pattern without torque discontinuity. In addition, because multi-mode controllers are not used, implementation is more straightforward. Simulation results show the voltage pattern changes smoothly when the motor speed changes, and consequently, torque control without torque discontinuity is possible in the field weakening area even with a six-step voltage pattern.