In this paper, we deal with the design of a model predictive control (MPC) for precise speed servo control of DC motor systems. The proposed controller is designed in the form of optimal control that calculates and outputs the optimized control input under constraints for each sampling. In particular, MPC designs the control inputs in advance for each sampling and predicts the outputs using them. Thus, it shows excellent control performance even in the case of disturbance or model uncertainty. The effectiveness of the proposed controller was demonstrated through computer simulations using MATLAB/Simulink and DC motor experimental system using real time controller. Moreover, the effectiveness of the proposed controller was confirmed by comparing its control performance with PID controller, which was tested under the same experimental condition as the MPC.
This paper proposes a method to improve the position control synchronization performance by synchronizing the controller operation between servo drives based on the synchronization signal of the EtherCAT(Ethernet for Control Automation Technology)distributed clock. In order to synchronize the operation of the controller between the servo drives, the phase of the operating frequency of the PWM(Pulse Width Modulation) module for motor control was synchronized based on the synchronization signal. At this time, the operation sequence of the current, speed, and position controller of the servo drive operating based on the PWM operating frequency was rearranged. Therefore, the servo drives on the network run the same controller at the same time. And the time at which the master's command is reflected to the drive's controller and the time at which the drive's status information is acquired coincided among the drives. After establishing an experimental environment in which servo drives are arranged in the EthercCAT network system, we verified that the position synchronization performance between servo drives applying the proposed method is improved.
In case of worm reducer, the worm and worm wheel are the significant design elements. Most of the worm and worm wheel are being importer and assembled because that the localization is inadequate. As the demand increases and the necessity of localization and precision grows, to develop them is now more important things.
In this study, we conducted the design, manufactured prototype and performance evaluation for worm reducer for dual lead 5.2:1 servo motor. The worm reducer is analyzed design reliability by finite element method. The performance evaluation for manufactured prototype worm reducer was conducted on the backlash, operation temperature and contact efficiency with/without load and satisfied for the all test items.
본고는 당나라 서예가 겸 서예이론가인 손과정이 직접 짓고 쓴 『서보 (書譜)』에 나타난 심미관을 살펴 그의 서예미학사상을 고찰하는데 있다. 손과정은 동진(東晉)시대 왕희지와 왕헌지의 필법을 얻은 서예가로 특 히 초서에 가장 뛰어났다. 더욱 그의 진적인 『서보』는 뛰어난 초서작 품인 동시에 내용에서도 박식하고 고상한 문장으로 서예이론뿐만 아니라 당시의 미학저작에서도 불후 걸작이라 칭하고 있다. 다시 말해서 서예로 서의 예술 가치를 가지고 있을 뿐만 아니라 이론으로서도 매우 가치 있 는 명작이다. 『서보』는 서예의 원류를 비롯하여 각 서체에 대한 기능과 특징, 그 리고 서예를 배우는 태도와 수양을 논술하고 있다. 특히 글씨 쓰는 기본 기법과 서예의 창작 경험들을 총괄하고 있다. 그는 서예의 골기(骨氣)에 있어 ‘양강(陽剛)의 아름다움’과 ‘음유(陰柔)의 아름다움’을 말하고, 의 (意)와 세(勢)의 통일을 말한다. 그리고 충화미(沖和美) 등으로 예술심미 를 논술하고 이들을 ‘도(道)’의 차원에 이입시키고 있다. 그러므로 손과정의 미학사상은 강하고 부드러움의 조화로 유가와 도가 의 서로 보완된 철리(哲理)가 내재되어 있다. 다시 말해서 유가의 “강건 유위 자강불식(剛健有爲, 自强不息)”과 도가의 “청정무위(淸靜無爲)”가 그 의 사상 저변에 깔려 있다. 그래서 손과정의 사상은 그의 서예에 나타난 ‘강하고 부드러움(剛柔)’을 함께하는 심미이상과 부합함을 알 수 있겠다.
This paper presents a method of measuring the 6 DOF motion of a micro object using images taken of interference fringes projected onto the object. Information from the fringe patterns allows for extracting the 6 DOF motion of the object in one image, allowing for real time measurement of the object's pose. This measurement technique is applied to a visual servo control scheme where the object's 6 DOF motion is controled. Experimental results of the developed system are presented.
Robotic manipulators are increasingly deployed in complex environments or to perform complex tasks. Studies on dual-arm-robots have been continually carried out in robotics areas to provide robots in dangerous environments, similar to those which human beings would be normally in, without a special change to the working environment. In previous study, a dual-arm-robot has been designed. The robot, however, has some defects in its heavy weight and big shape. In order to reduce weight of an arm robot, the robot has been designed using a hollow-shaft-servo- assembly. The hollow-shaft-servo-assembly is composed of a hollow-shaft-servo-motor, a hollow- shaft-harmonic-drive, a hollow-shaft-brake, a hollow-shaft-encoder, and a servo-drive.
The energy saving is one of the most important factors for profit in marine transportation. In order to reduce the fuel oil consumtion the ship's propulsion efficiency must be increased as possible. The propulsion efficiency depends upon a combination of an engine and a propeller. The propeller has better efficiency as lower rotational speed. This situation led the engine manufacturers to design the engine that has low speed, long stroke and a small number of cylinders. Consequently, the variation of rotational torque became larger than before because of the longer delay-time in fuel oil injection process and an increased output per cylinder. As this new trends the conventional mechanical-hydrualic governors for engine speed control have been replaced by digital speed controllers which adopted the PID control or the optimal control algorithm. But these control algorithms have not enough robustness to suppress the variation of the delay-time and the parameter perturbation. In this paper we consider the delay-time and the perturbation of engine parameters as the modeling uncetainties. Next we design the robust servo controller which has zero offset in steady state engine speed, based on H sub(∞) control theory. The validity of the controller was investigated through the response simulation. We used a personal computer and an analog computer as the digital controller and the engine (plant) part respectively. And, we could certify that the designed controller maintains its robust servo performance even though the engine parameters may vary.
This paper considers robust stability and transient behavior of the Two - Degree - of - Freedom(2DOF) servosystem. A class of uncertainties allowed in the plant model is obtained, to which the servosystem is robustly stable for any gain of the integral compensator. This result implies that if the plant uncertainty is the allowable set defined by the condition, a high - gain compensation can be carried out preserving stability to achieve a high - speed tracking response. The transient behavior attainable by the limit of the high - gain compensation is calculated using the singular perturbation approach.
전원을 단락시킴이 없는 SCR이중 브리지 트리거 방식을 고안하여, 정역전이 가능한 SCR 서보증폭기로 구성하여 본 결과 다음과 같은 결론을 내릴 수 있었다. I. 출력전압의 부호를 변경시킬 때 현재의 전언부호가 반전될 때까지 도통 상태를 유지시키다가, 전원부호가 반전된 이후 적절한 SCR을 도통 시킴으로서 크리거 실패가 없게 되어, 전원을 단락시키지 않게 되고 SCR의 소손을 막을 수 있었다. II. -에서 약 30Hz 부근까지는 60Hz의 전원으로서 원하는 출력을 표현할 수 있었는데, 이는 대형 직류 전동기의 동특성을 충분히 확보할 수 있는 값이다. III. 유도성 부하의 경우라도 이미 도통된 SCR을 통하여 유동성부하L에 저장될 수 있는 에너지의 총량은 전원의 반주기 시간과 전원이 파고치값 한계내이므로, 다음 반주기동안 부호만 반전된 전원 전압과 동일한 반주기의 시간이 존재하므로, 에너지 보존의 법칙에 의해 반드시 다음 반주기 안에 현재도통된 SCR은 소호되게 되므로 트리거실패는 존재하지 않는다.
This paper presents a design method of fuzzy controller based on TSK fuzzy model. By using the proposed method, we can design fuzzy controller mathematically, which guarantees the stability of fuzzy system. We derived a theorem related to the stability of fuzzy system. In that theorem, we show that the fuzzy system has the same stable state transition matrix as we desire. The validity of the proposed method is shown through an experiment of DC motor velocity control.
The Variable Structure System(VSS) will be of much intrest to educators and design engineers who wish to demonstrate and investigate sophisticated position control methods and their applications. This paper describes DC motor position control by means of VSS concept. The control scheme is derived, implemented and tested in the laboratory where IBM AT computer has been used as a digital controller to control a representative servo system. The control system schematic is given and sample results are shown for illustration. This experiment may serve as a basis for further application of VSS.
비선형의 특성을 갖고 있는 DC 서보 모터의 속도 제어에 퍼지 제어기의 사용을 제안하였다. 퍼지 제어기는 퍼지 모델로부터 설계되며, 그 퍼지 모델은 시스템의 입출력 데이터로 인식되고 비선형 시스템의 표현에 뛰어난 능력을 갖고 있다. 따라서 퍼지 모델로부터 설계되는 퍼지 제어기는 시스템의 비선형 특성이 잘 반영되어지며 그러한 점은 서보 모터의 속도 제어에 응용한 결과 잘 알 수 있었다. 즉 퍼지 제어기에 비해 고속 제어가 가능해졌으며 정상 리플(ripple)이 감소하였다. 또한 이 퍼지 제어기에서 사용되는 퍼지 집합의 멤버쉽 함수는 간단한 선형 구분 함수이므로 퍼지 제어기도 간략한 형태로 표현되었다
By using the accelerometer, there are two techniques of measuring the response from structures: forced vibration and ambient vibration method. Recently, ambient vibration technique is successfully being used for bridges, buildings, dams, and mechanical structures. In this study, we briefly introduce and describe a health monitoring system which measures and predicts the structural integrity of the entire structure through the measurement of ambient vibration characteristics and tilt of the structure by using the domestic-made high precision accelerometer. The high precision servo accelerometer is applied in inertial navigation system of the various weapon systems such as missiles, tanks, and armored vehicles.