• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 춘계학술대회 논문집
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• pp.173-179
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• 2002

This paper presents a new approach to the design of adaptive control system using DSPs(TMS320C50) fur robotic manipulators to achieve trajectory tracking angles. Digital signal processors are used in implementing real time adaptive control algorithms to provide motion for robotic manipulators. In the proposed scheme, adaptation laws are derived from the improved second stability analysis based on the indirect adaptive control theory. The proposed control scheme is simple in structure, fast in computation, an suitable fur implementation of real-time control. Moreover, this scheme does not require an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by experimental results for a SCARA robot.

• 대한기계학회논문집A
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• 제26권2호
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• pp.399-405
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• 2002

This paper proposes a new type of piezoactuator-driven valve system. The piezoceramic actuator bonded to both sides of a flexible beam surface makes a movement required to control the pressure at the flapper-nozzle of a pneumatic valve system. After establishing a dynamic model, an appropriate size of the valve system is designed and manufactured. Subsequently, a robust H$_{\infty}$ control algorithm is formulated in order to achieve accurate tracking control of the desired pressure. The controller is experimentally realized and control performance for the sinusoidal pressure trajectory is presented in time domain. The control bandwidth of the valve system, which directly represents the fastness, is also evaluated in the frequency domain.

• 한국정밀공학회지
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• 제25권10호
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• pp.67-76
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• 2008

In this research, a simple technique for designing PID controller, which guarantees robust stability for two-mass systems with parameter uncertainties as well as rigid-body behavior and zero steady-state error,is described. As well, such a PID controller is designed to mate two important frequencies, at which the given system is excited, very close so that an appropriate reference profile generated by using command shaping techniques can cover those two frequencies. Root-locus analysis. which shows traces of closed-loop poles for the given system, is used to design this PID controller. Finally, feedforward controller is added to improve tracking performance of the closed-loop system. Simulation for a system with a flexible mode and parameter uncertainties is executed to prove the feasibility of this technique.

• 한국군사과학기술학회지
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• 제4권1호
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• pp.73-82
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• 2001

In this Paper, slack is computed from a comparision of the cable pay out rate and the ship ground speed in accordance with laying conditions, and the speed controller of the cable engine based on an $H^{\infty}$ servo control is designed for adjusting the cable engine in order to lay a desired amount of slack. The controller is designed to have the robust tracking property of the cable engine under disturbances. The performance of the designed controller is evaluated by computer simulation, and, consequently, a feasibility study for laying the submarine cable stably is done through analyzing simulation results.

• International Journal of Automotive Technology
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• 제5권2호
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• pp.123-133
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• 2004

This paper describes a robust and fast wheel slip tracking control using a moving sliding surface technique. A traction control system (TCS) is the active safety system used to prevent the wheel slipping and thus improve acceleration performance, stability and steerability on slippery roads through the engine torque and/or brake torque control. This paper presents a wheel slip control for TCS through the engine torque control. The proposed controller can track a reference input wheel slip in a predetermined time. The design strategy investigated is based on a moving sliding surface that only contains the error between the reference input wheel slip and the actual wheel slip. The used moving sliding mode was originally designed to ensure that the states remain on a sliding surface, thereby achieving robustness and eliminating chattering. The improved robustness in driving is important due to changes, such as from dry road to wet road or vice versa which always happen in working conditions. Simulations are performed to demonstrate the effectiveness of the proposed moving sliding mode controller.

• 한국항공우주학회지
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• 제45권8호
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• pp.647-661
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• 2017

본 논문에서는 탐사선을 소천체에 착륙시키기 위한 자율 착륙 기법을 제시하였다. 제시된 기법은 탐사선이 스스로 착륙을 위한 위치 및 자세 프로파일을 생성하고 이를 추종하는 구조를 가지며, 위치 및 자세 추종을 위한 제어기를 설계함에 있어 소천체 및 탐사선의 환경 불확실성에 대해 강인한 특성을 갖는 이산 슬라이딩 모드 제어법칙을 바탕으로 하였다. 착륙을 위한 자율 항법 기법으로는 시각기반 관성항법을 적용하였으며, 제시된 착륙 기법은 다양한 불확실성이 존재하는 상황에서의 수치 시뮬레이션을 통해 검증되었다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1500-1503
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• 1996

This paper combines the disturbance accommodating control(DAC) and nonlinear model inversion control for a skid-to-turn(STT) missile. The missile autopilot may be designed to be robust with respect to a variety of uncertainties. We proposes the two step control design method. Nonlinear model inversion control is used as the main design method. Due to the model uncertainties and external disturbances, the exact nonlinear model inversion can not be achieved. DAC is designed to detect, to identify, and to compensate these uncertainties. DAC's disturbance observer is linear. Thus it is easy to implement. It does not cause the convergence problem due to coexistence between the modeling uncertainties and external disturbances. 6 DOF simulation results show that the proposed method may improve the missile tracking performance.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2275-2278
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• 2005

In this paper, a control algorithm for a servo manipulator is focused on. A servo manipulator system has been developed for remotely handling radioactive materials in a hot cell. It is driven by servo motors. The torque from a servo motor is transferred through a reducer to the corresponding axis. The PID control algorithm is a simple and effective algorithm for such application. However, since friction degrades the algorithm's performance, friction has to be considered and compensated. The major aberrations are the positional tracking errors and the limit cycle. The authors have considered a switching term to a conventional PID algorithm to reduce the friction's effect. It has been tested by a hardware test.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.2279-2284
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• 2005

Generally, biped walking is difficult to control because it is a nonlinear system with various uncertainties. In this paper, we design a robust control system based on sliding-mode control (SMC) of 5-link biped robot using the wavelet neural network(WNN), in order to improve the efficiency of position tracking performance of biped locomotion. In our control system, the WNN is utilized to estimate uncertain and nonlinear system parameters, where the weights of WNN are trained by adaptive laws that are induced from the Lyapunov stability theorem. Finally, the effectiveness of the proposed control system is verified by computer simulations.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1996년도 춘계학술대회 논문집
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• pp.472-477
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• 1996

This paper presents a new approachtothe design of adaptive control system using DSPs(TMS320C30) for robotic manipulators to achieve trajectory tracking by the joint angles. Digital signal processors are used in implementing real time adaptive control algorithms to provide an enhanced motion control for robotic manipulators. In the proposed control scheme, adaptation laws are derived from the improved Lyapunov second stability analysis method based on the adaptive model reference control theory. The adaptive controller consists of an adaaptive feedforward controller, feedback controller, and PID type time-varying auxillary control elements. The prpposed adaptive control scheme is simple in structure, fast in computation, and suitable for implementation of real-time control. Moreover, this scheme does not require an accurate dynamic modeling, nor values of manipulator parameters and payload. Performance of the adaptive controller is illustrated by simulation and experimental results for a SCARA robot.