Controller Design for Active Closed-Loop Control of Cavity Flows

Author(s):  
Hitay Ozbay ◽  
Onder Efe ◽  
Mo Samimy ◽  
Edgar Caraballo ◽  
Jim DeBonis ◽  
...  
2008 ◽  
Vol 123 (5) ◽  
pp. 3679-3679
Author(s):  
Louis Cattafesta ◽  
Srinivasan Arunajatesan ◽  
Qi Song ◽  
Cesar Moreno ◽  
Miguel Palaviccini

Author(s):  
Srinivasan Arunajatesan ◽  
Louis Cattafesta ◽  
Qi Song ◽  
Miguel Palaviccini ◽  
Cesar Moreno

2005 ◽  
Vol 128 (1) ◽  
pp. 378-381 ◽  
Author(s):  
Jeetae Kim

In this study a hardware simulator and controller for web transport process are developed. First the dynamics of web transport process is analyzed for simulator and controller design. An example Polypropylene transport process is investigated and its simplified transport model is derived. Then the web transport process simulator and its controller are developed. Accurate tension force control is needed to produce high quality web formed materials. The process controller uses the loadcell as a tension measuring device and closed-loop control is used for tension force regulation. The response of the system is tested under the disturbances in tension and the experimental results show that the system regulates tension disturbances properly.


Author(s):  
Pauli Mustalahti ◽  
Jouni Mattila

Hydraulic manipulators are extensively utilized to move heavy loads in many industrial tasks. In commercial applications, a manipulator base is required to rotate a motion range of the full 360°. This is usually implemented by using a hydraulic rack and pinion gear actuator. Due to the manipulator’s long reach and heavy loads, manipulator tip acceleration can produce significant torque to the rotation gear in free-space motion. Imposed by nonlinear dynamical behavior (involving, e.g., the gear backlash and actuator friction) added to high inertia, a system closed-loop control design becomes a challenging task. An advanced closed-loop control enables to increase the automation-level of hydraulic manipulators. This study designs a novel subsystem-dynamics-based controller for a hydraulic rack and pinion gear actuator utilizing the control design principles of the virtual decomposition control (VDC) approach. An adaptive backlash compensation is incorporated in the control design. Furthermore, the proposed controller is implemented in previously-designed state-of-the-art hydraulic manipulator control. The stability of the overall control design is proven. Experiments with a full-scale commercial hydraulic manipulator demonstrate the effectiveness of the proposed adaptive backlash compensation and the overall control performance.


2005 ◽  
Vol 128 (4) ◽  
pp. 413-428 ◽  
Author(s):  
Neil D Sims

Semiactive vibration dampers offer an attractive compromise between the simplicity and fail safety of passive devices, and the weight, cost, and complexity of fully active systems. In addition, the dissipative nature of semiactive dampers ensures they always remain stable under closed loop control, unlike their fully active counterparts. However, undesirable limit cycle behavior remains a possibility, which is not always properly considered during the controller design. Smart fluids provide an elegant means to produce semiactive damping, since their resistance to flow can be directly controlled by the application of an electric or magnetic field. However, the nonlinear behavior of smart fluid dampers makes it difficult to design effective controllers, and so a wide variety of control strategies has been proposed in the literature. In general, this work has overlooked the possibility of undesirable limit cycle behavior under closed loop conditions. The aim of the present study is to demonstrate how the experimentally observed limit cycle behavior of smart dampers can be predicted and explained by appropriate nonlinear models. The study is based upon a previously developed feedback control strategy, but the techniques described are relevant to other forms of smart damper control.


2013 ◽  
Vol 23 (10) ◽  
pp. 1401-1414 ◽  
Author(s):  
Konstantinos G. Papadopoulos ◽  
Nikolaos D. Tselepis ◽  
Nikolaos I. Margaris

Sign in / Sign up

Export Citation Format

Share Document