scholarly journals Vibrations of Air-Coupled Web Systems

2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Dan Feng ◽  
Jie Wang ◽  
George T.-C. Chiu ◽  
Arvind Raman
Keyword(s):  
Closed Form ◽  
Process Monitoring ◽  
Low Frequency ◽  
Stretchable Electronics ◽  
Continuous Manufacturing ◽  
Monitoring And Control ◽  
Roll To Roll ◽  
Aspect Ratios ◽  
Manufacturing Technologies ◽  
Web Systems

Abstract The prediction and measurement of vibrations of the low-frequency transverse modes of tensioned webs are of increasing interest for process monitoring, quality control, and process stability in roll-to-roll flexible hybrid and stretchable electronics manufacturing, nanomanufacturing, coated layer patterning, and other continuous manufacturing technologies. Acting as distributed added mass, the surrounding air significantly affects the frequency responses of taut thin webs in ambient roll-to-roll processes in comparison with those in vacuo. In this paper, we present closed-form, semi-analytical, universal hydrodynamic functions used to accurately predict the lowest symmetric and anti-symmetric transverse frequency response for any uniaxially tensioned web of arbitrary material and aspect ratio used in roll-to-roll processes. Experimental validation is carried out by using pointwise laser measurements of acoustically excited webs with different pre-tensions, web materials, and aspect ratios. These closed-form hydrodynamic functions provide roll-to-roll process designers a convenient way to predict the lowest frequencies of such web systems without the need to resort to computationally intensive methods; alternately, these functions allow for the quick identification of conditions when air-coupling is important to determine the web’s vibration response. The results presented herein are expected to help ongoing efforts to improve process monitoring and control in a variety of roll-to-roll continuous manufacturing technologies.

A Review on Process Monitoring and Control in Metal-Based Additive Manufacturing

2014 ◽  
Vol 136 (6) ◽  
Author(s):  
Gustavo Tapia ◽  
Alaa Elwany
Keyword(s):  
Additive Manufacturing ◽  
Process Monitoring ◽  
Monitoring And Control ◽  
Part Quality ◽  
Industrial Sectors ◽  
Process Monitoring And Control ◽  
Traditional Manufacturing ◽  
Manufacturing Technologies ◽  
And Control ◽  
Am Processes

There is consensus among both the research and industrial communities, and even the general public, that additive manufacturing (AM) processes capable of processing metallic materials are a set of game changing technologies that offer unique capabilities with tremendous application potential that cannot be matched by traditional manufacturing technologies. Unfortunately, with all what AM has to offer, the quality and repeatability of metal parts still hamper significantly their widespread as viable manufacturing processes. This is particularly true in industrial sectors with stringent requirements on part quality such as the aerospace and healthcare sectors. One approach to overcome this challenge that has recently been receiving increasing attention is process monitoring and real-time process control to enhance part quality and repeatability. This has been addressed by numerous research efforts in the past decade and continues to be identified as a high priority research goal. In this review paper, we fill an important gap in the literature represented by the absence of one single source that comprehensively describes what has been achieved and provides insight on what still needs to be achieved in the field of process monitoring and control for metal-based AM processes.

scholarly journals The Use of Machine Tool Internal Encoders as Sensors in a Process Monitoring System

2013 ◽  
Vol 7 (4) ◽  
pp. 410-417 ◽  
Author(s):  
Tomas Beno ◽  
◽  
Jari Repo ◽  
Lars Pejryd ◽  
Keyword(s):  
Tool Wear ◽  
Machine Tool ◽  
Process Monitoring ◽  
Low Frequency ◽  
Machining Process ◽  
Process Conditions ◽  
Monitoring And Control ◽  
Signal Features ◽  
Process Monitoring And Control ◽  
Cutting Force Components

Tool wear in machining changes the geometry of the cutting edges, which affects the direction and amplitudes of the cutting force components and the dynamics in the machining process. These changes in the forces and dynamics are picked up by the internal encoders and thus can be used for monitoring of changes in process conditions. This paper presents an approach for the monitoring of amulti-toothmilling process. The method is based on the direct measurement of the output from the position encoders available in the machine tool and the application of advanced signal analysis methods. The paper investigates repeatability of the developed method and discusses how to implement this in a process monitoring and control system. The results of this work show that various signal features which are correlated with tool wear can be extracted from the first few oscillating components, representing the low-frequency components, of the machine axes velocity signatures. The responses from the position encoders exhibit good repeatability, especially short term repeatability while the long-term repeatability is more unreliable.

scholarly journals Potential applications of halophilic microorganisms for biological treatment of industrial process brines contaminated with aromatics

2021 ◽  
Author(s):  
Thomas Mainka ◽  
David Weirathmüller ◽  
Christoph Herwig ◽  
Stefan Pflügl
Keyword(s):  
Wastewater Treatment ◽  
Process Monitoring ◽  
Industrial Wastewater ◽  
Continuous Process ◽  
Scale Up ◽  
Monitoring And Control ◽  
Saline Wastewater ◽  
Halophilic Microorganisms ◽  
Industrial Sectors ◽  
And Control

Abstract Saline wastewater contaminated with aromatic compounds can be frequently found in various industrial sectors. Those compounds need to be degraded before reuse of wastewater in other process steps or release to the environment. Halophiles have been reported to efficiently degrade aromatics, but their application to treat industrial wastewater is rare. Halophilic processes for industrial wastewater treatment need to satisfy certain requirements: a continuous process mode, low operational expenditures, suitable reactor systems and a monitoring and control strategy. The aim of this review is to provide an overview of halophilic microorganisms, principles of aromatic biodegradation, and sources of saline wastewater containing aromatics and other contaminants. Finally, process examples for halophilic wastewater treatment and potential process monitoring strategies are discussed. To further illustrate the significant potential of halophiles for saline wastewater treatment and to facilitate development of ready-to-implement processes, future research should focus on scale-up and innovative process monitoring and control strategies.

Fractal Pattern Recognition of Image Profiles for Manufacturing Process Monitoring and Control

2018 ◽  
Author(s):  
Farhad Imani ◽  
Bing Yao ◽  
Ruimin Chen ◽  
Prahalada Rao ◽  
Hui Yang
Keyword(s):  
Additive Manufacturing ◽  
Process Monitoring ◽  
Manufacturing Process ◽  
Manufacturing Systems ◽  
Experimental Studies ◽  
Precision Machining ◽  
Monitoring And Control ◽  
Process Monitoring And Control ◽  
Ultra Precision ◽  
And Control

Nowadays manufacturing industry faces increasing demands to customize products according to personal needs. This trend leads to a proliferation of complex product designs. To cope with this complexity, manufacturing systems are equipped with advanced sensing capabilities. However, traditional statistical process control methods are not concerned with the stream of in-process imaging data. Also, very little has been done to investigate nonlinearity, irregularity, and inhomogeneity in image stream collected from manufacturing processes. This paper presents the multifractal spectrum and lacunarity measures to characterize irregular and inhomogeneous patterns of image profiles, as well as detect the hidden dynamics of the underlying manufacturing process. Experimental studies show that the proposed method not only effectively characterizes the surface finishes for quality control of ultra-precision machining but also provides an effective model to link process parameters with fractal characteristics of in-process images acquired from additive manufacturing. This, in turn, will allow a swift response to processes changes and consequently reduce the number of defective products. The proposed fractal method has strong potentials to be applied for process monitoring and control in a variety of domains such as ultra-precision machining, additive manufacturing, and biomanufacturing.

Sign in / Sign up

Export Citation Format

Share Document