Flow sensing and control strategies to address race-tracking disturbances in resin transfer molding. Part I: design and algorithm development

2004 ◽  
Vol 35 (10) ◽  
pp. 1149-1159 ◽  
Author(s):  
Kuang-Ting Hsiao ◽  
Suresh G. Advani
Keyword(s):  
Control Strategies ◽  
Resin Transfer Molding ◽  
Algorithm Development ◽  
Transfer Molding ◽  
Flow Sensing ◽  
And Control

Towards Practical Flow Sensing and Control via POD and LSE Based Low-Dimensional Tools (Keynote Paper)

2002 ◽  
Author(s):  
Jeffrey Taylor ◽  
M. N. Glauser
Keyword(s):  
Velocity Field ◽  
Control Strategies ◽  
Adverse Pressure Gradient ◽  
Wall Pressure ◽  
Mean Flow ◽  
Flow Sensing ◽  
Active Feedback ◽  
Low Dimensional ◽  
And Control ◽  
Proper Orthogonal

We present the application of Proper Orthogonal Decomposition (POD) and Linear Stochastic Estimation (LSE) based low-dimensional methods to the flow over a backward facing ramp with an adjustable flap above the ramp which allows for dynamic variation of the adverse pressure gradient. There is a range of flap angles where the flow is incipiently separated so that this relatively simple experiment can be used to flush out ideas for active feedback separation control strategies. The study utilized a combination of PIV and multi-point wall pressure measurements to estimate the full velocity field (mean plus fluctuating) from a modified complementary technique. Specifically we want to identify a low-dimensional mean flow to observe when the profiles are inflectionary, i.e., the incipient condition, just from wall pressure. We demonstrate via this method, that a reasonable estimate of the low dimensional full velocity field can be obtained. This is important for practical active feedback flow control strategies since from wall pressure we can estimate the state of the flow without resorting to probes in the flow.

A Robotic System for Real-Time Resin Flow Modification During Vacuum-Assisted Resin Transfer Molding

2006 ◽  
Author(s):  
Scott Kasprzak ◽  
John Nasr ◽  
Michael Fuqua ◽  
Jim Glancey
Keyword(s):  
Real Time ◽  
Vacuum Chamber ◽  
Control Strategies ◽  
Resin Transfer Molding ◽  
Element Model ◽  
Robotic System ◽  
Resin Flow ◽  
Transfer Molding ◽  
Flow Modification ◽  
Molded Part

To complement existing resin flow control strategies currently under development for Vacuum-Assisted Resin Transfer Molding (VARTM), and to provide the ability to react to unexpected changes in resin behavior during injection, a new technique for resin flow manipulation has been investigated. This approach consists of a semi-cylindrical shaped vacuum chamber placed on a mold which, when evacuated, increases the permeability of the region under the chamber by lifting the bag atop the mold. A finite element model has been developed to predict the resin flow within the mold while using the external chamber. Laboratory testing has shown significant modification in resin flow with reduced injection time. Using the external chamber, a robotic system has been prototyped that identifies dry regions forming during injection via computer vision, deploys the vacuum chamber over the mold with a robotic arm, and actuates the chamber in order to modify and correct the resin flow within the mold. Test results using lab-scale molds with large variations in preform permeabilities indicate that the robotic system can correct and/or modify the resin flow within a mold in real time, thus eliminating dry, unimpregnated regions. This computer-based method has the potential to significantly enhance molded part quality and consistency by eliminating resin starved regions within a molded composite part.

Towards Practical Flow Sensing and Control via POD and LSE Based Low-Dimensional Tools

2004 ◽  
Vol 126 (3) ◽  
pp. 337-345 ◽  
Author(s):  
J. A. Taylor ◽  
M. N. Glauser
Keyword(s):  
Velocity Field ◽  
Control Strategies ◽  
Accurate Estimate ◽  
Wall Pressure ◽  
Flow Sensing ◽  
Image Velocimetry ◽  
Active Feedback ◽  
Low Dimensional ◽  
And Control ◽  
Proper Orthogonal

Low-dimensional methods including the Proper Orthogonal Decomposition (POD) and Linear Stochastic Estimation (LSE) have been applied to the flow between a backward facing ramp and an adjustable flap. A range of flap angles provide a flow which is incipiently separated and can be used to flesh out ideas for active feedback separation control strategies. The current study couples Particle Image Velocimetry (PIV) and multi-point wall pressure measurements using POD and LSE to estimate the full velocity field from the wall pressure alone. This technique yields a sufficiently accurate estimate of the velocity field that the incipient condition can be detected. The ability to estimate the state of the flow without inserting probes into the flow is important for the development of practical active feedback flow control strategies.

Effective infection prevention and control strategies in a large accredited psychiatric facility in Singapore

2020 ◽  
Author(s):  
Daniel Poremski ◽  
Sandra Henrietta Subner ◽  
Grace Lam Fong Kin ◽  
Raveen Dev Ram Dev ◽  
Mok Yee Ming ◽  
...  
Keyword(s):  
Mental Health ◽  
Prevention And Control ◽  
Infection Prevention ◽  
Control Strategies ◽  
Infection Prevention And Control ◽  
Psychiatric Facility ◽  
Essential Services ◽  
Community Transmission ◽  
And Control

The Institute of Mental Health in Singapore continues to attempt to prevent the introduction of COVID-19, despite community transmission. Essential services are maintained and quarantine measures are currently unnecessary. To help similar organizations, strategies are listed along three themes: sustaining essential services, preventing infection, and managing human and consumable resources.

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