• Title/Summary/Keyword: Sliding mode Control

Search Result 1,387, Processing Time 0.021 seconds

Modal Analysis and Velocity Control of Bowl Parts Feeder Activated by Piezoactuators (압전작동기로 구동 되는 보울 파트 피더의 모드 해석과 이송 속도 제어)

  • Lee, Dong-Ho;Choe, Seung-Bok;Kim, Jae-Hwan
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.24 no.4 s.175
    • /
    • pp.839-847
    • /
    • 2000
  • This paper presents modal analysis and mean conveying velocity (M.C.V.) control of bowl parts feeder activated by piezoactuators. Bowl parts feeders are being widely used in many industry fields for automatic assembly line. In general, the electromagnet has been and being used as exciting actuator of these vibratory bowl feeders. However, because of complexity of its mechanism and limited capability of the electromagnet actuator, there exist various impending problems such as severe noise, nonlinear motion of parts, passive characteristics and so forth. As one of solutions for these problems, piezoelectric actuators as new actuating technology have been proposed recently to excite the bowl parts feeder. In this paper, modal analysis of the proposed model has been performed to examine the modal characteristics of the model by using commercial FEM software and modeling with respects to MCV is constructed. Finally, MCV of the parts is to be controlled to track the desired one with PID controller.

Sensorless Sine-Wave Controller IC for PM Brushless Motor Employing Automatic Lead-Angle Compensation

  • Kim, Minki;Heo, Sewan;Oh, Jimin;Suk, Jung-Hee;Yang, Yil Suk;Park, Ki-Tae;Kim, Jinsung
    • ETRI Journal
    • /
    • v.37 no.6
    • /
    • pp.1165-1175
    • /
    • 2015
  • This paper presents an advanced sensorless permanent magnet (PM) brushless motor controller integrated circuit (IC) employing an automatic lead-angle compensator. The proposed IC is composed of not only a sensorless sine-wave motor controller but also an isolated gate-driver and current self-sensing circuit. The fabricated IC operates in sensorless mode using a position estimator based on a sliding mode observer and an open-loop start-up. For high efficiency PM brushless motor driving, an automatic lead-angle control algorithm is employed, which improves the efficiency of a PM brushless motor system by tracking the minimum copper loss under various load and speed conditions. The fabricated IC is evaluated experimentally using a commercial 200 W PM brushless motor and power switches. The proposed IC is successfully operated without any additional sensors, and the proposed algorithm maintains the minimum current and maximum system efficiency under $0N{\cdot}m$ to $0.8N{\cdot}m$ load conditions. The proposed IC is a feasible sensorless speed controller for various applications with a wide range of load and speed conditions.

Development of Nonlinear Control Algorithm for Automatic Berthing of Ships

  • Won, Moon-Cheol;Hong, Seong-Kuk;Jung, Yun-Ha;Kim, Sun-Young;Son, Nam-Sun;Yoon, Hyun-Gyu
    • Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
    • /
    • 2006.11a
    • /
    • pp.359-362
    • /
    • 2006
  • This study develops an automatic berthing control algorithm for ships with a bow thruster and a stern thruster as well as a rudder. A nonlinear mathematical model for low speed maneuvering of ships is used to develop a MIMO(multi-input multi-output) nonlinear control algorithm. The algorithm consists of two parts, which are forward velocity control and heading angle control. The control algorithm is designed based on the longitudinal and yaw dynamic models of ships. The desired heading angle is obtained by the so called "Line of Sight" method. An optimal control force allocation method of the rudder and the thrusters is suggested. The nonlinear control algorithms are tested by numerical simulations using MATLAB, and shows good tracking performances.

  • PDF

A Study on the Position Control of an Electro-Hydraulic Servomechanism Using Variable Structure System (가변구조를 이용한 전기-유압서보계의 위치제어에 관한 연구)

  • 허준영;권기수;하석홍;조겸래;이진걸
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.13 no.2
    • /
    • pp.213-220
    • /
    • 1989
  • This paper describes the application of the variable structure control(VSC) concept for the position control of an electro-hydraulic servomotor system. The basic philosopy of VSC is that the structure of the feedback control is altered as the state crosses discontinuity surfaces in the state space with the result that certain desirable properties are achieved. The switching of the control function yields total(or selective) invariance to system parameter variations and disturbances, and closed loop eigen value placement in time-varing and uncertain systems. The control scheme is derived, implemented and tested in the laboratory where analog controller have been used to control the representive servosystem. The control system schematics are given and simple results are shown for illustration. And the results of variable structure system for the electro-hydraulic servomotor were compared to that of the fixed structure system when load disturbance and system parameter variation exists.

Nonlinear Attitude Control of Drones Using Control Moment Gyros (CMG를 활용한 드론의 비선형 자세 제어 기법)

  • Jang, Seok-ho;Leeghim, Henzeh
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.49 no.10
    • /
    • pp.821-828
    • /
    • 2021
  • Quadrotors relatively smaller and lighter than other aircraft have a disadvantage of being sensitive to the external disturbances. In order to solve this disadvantage, many studies have been conducted by various control techniques robust to disturbances. In this paper, CMGs (Control Moment Gyros) introducing relatively large control torque with an identical amount of electric powers are applied to cancel the external disturbances. Two CMGs are considered to control the attitude of quadrotors so that a multi-copter installed with two CMGs and four rotors are introduced for this work. Finally, to verify the control performance of the proposed system by the CMGs, a numerical simulation conducted in the given harsh environment.

Control of a Unicycle Robot using a Non-model based Controller (비 모델 외바퀴 로봇의 제어)

  • An, Jae-Won;Kim, Min-Gyu;Lee, Jangmyung
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.20 no.5
    • /
    • pp.537-542
    • /
    • 2014
  • This paper proposes a control system to keep the balance of a unicycle robot. The robot consists of the disk and wheel, for balancing and driving respectively, and the tile angle is measured and used for balancing by the IMU sensor. A PID controller is designed based on a non-model based algorithm to prove that it is possible to control the unicycle robot without any approximated linear system model such as the sliding mode control algorithm. The PID controller has the advantage that it is simple to design the controller and it does not require an unnecessary complex formula. In this paper, assuming that the pitch and roll axis are dynamically decoupled, each of the two controllers are designed separately. A reaction wheel pendulum method is used for the control of the roll axis, that is, for balancing and an inverted pendulum concept is used for the control of the pitch axis. To confirm the performance of the proposed controllers using MATLAB Simulink, the dynamic equations of the robot are derived.

Incremental Twisting Compensator for Performance Improvement of Helicopter Control (헬리콥터 제어 성능 개선을 위한 증분 트위스팅 보상기)

  • Seo, Gang-Ho;Ju, Jongin;Kim, Yoonsoo
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • v.49 no.3
    • /
    • pp.213-219
    • /
    • 2021
  • In this paper, an incremental twisting compensator is proposed for improving the performance of helicopter control and tested on an in-house full-scale helicopter simulator. The proposed compensator has a merit in that an incremental control input (a second-order sliding mode control input or so-called twisting control input) is simply added to improve the performance of helicopter control, while the original flight control structure remains untouched. The proposed control technique has been shown to improve the transient and steady-state response of the in-house helicopter simulator.

Design, Control and Localization of Underwater Mine Disposal Robots (수중 기뢰 제거 로봇의 설계, 제어 및 위치 추정)

  • Moon, Yong Seon;Ko, Nak Yong;Sur, Joono
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.19 no.9
    • /
    • pp.805-812
    • /
    • 2013
  • This paper describes the design, control, and localization which comprise major aspects of the development of underwater robots for the mine disposal. The developed robots are called the Mine Killer (MK-1) and MK-2. MK-1 had been developed from September 2009 and was presented at the 9-th International Symposium at NPS Monterey CA, on May 17-21, 2010[1]. The paper presents design of MK-1 and MK-2 in detail with comparison of these two versions of MKs. Then it derives hydrodynamic coefficients of MK-1. Based on the coefficients, the motion of MK-1 is simulated for straight line motion and circular motion. Also simulation results for PD control, LQ control and sliding mode control are presented. Finally, it shows a particle filter method for localization of MK-1 and MK-2 using simple range data from acoustic beacons.

Disc Displacement Control of the Emergency Shut-Down Valve for LNG Bunkering (LNG 벙커링용 비상차단 밸브 디스크 변위 제어에 관한 연구)

  • Yoon, Jin Ho;Park, Ju Yeon;Jang, Ji Seong
    • Journal of Drive and Control
    • /
    • v.18 no.4
    • /
    • pp.28-34
    • /
    • 2021
  • Among the currently available types of fuel, LNG emits a relatively small amount of nitrogen oxide and carbon dioxide when it burns in the engine. However, since LNG is a flammable material, leakage during bunkering can lead to accidents, such as fires. Therefore, it is necessary to install a remote operation emergency shut-down (ESD) valve to block the flow and leakage of LNG in an emergency situation that occurs during bunkering. The ESD valve uses a hydraulic driving device consisting of a hydraulic control valve and a hydraulic motor to control globe valve disc displacement, which regulates the flow path for LNG transfer. At this time, there are various nonlinearities in hydraulic driving devices; hence, it is necessary to design a controller with robust control performance against these uncertainties. In this study, modeling of the ESD valve was carried out, and a sliding mode controller to control the displacement of the globe valve disc was designed. As a result, it was confirmed that the designed control performance could be achieved by overcoming nonlinearity characteristics using the designed controller.

Adaptive Algorithms for Yaw Moment Distribution with ESC and ARS (적응 알고리즘을 이용한 ESC와 ARS 기반 요 모멘트 분배)

  • Yim, Seongjin
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.40 no.12
    • /
    • pp.997-1003
    • /
    • 2016
  • This paper presents an application of adaptive algorithms for yaw moment distribution with electronic stability control (ESC) and active rear steering (ARS) in integrated chassis control (ICC). Integrated chassis control consists of upper- and lower-level controllers. In the upper-level controller, the control yaw moment is computed with sliding mode control required to stabilize a vehicle. In the lower-level controller, adaptive algorithms are applied to determine the required brake pressure of ESC and the necessary steering angle of ARS, in order to generate the control yaw moment. Simulation is performed using the vehicle simulation package CarSim to validate the proposed method.