Robotic and automatic welding development at the Marshall Space Flight Center

Welding automation is the key to two major development programs to improve quality and reduce the cost of manufacturing space hardware currently undertaken by the Materials and Processes Laboratory of the NASA Marshall Space Flight Center. Variable polarity plasma arc welding has demonstrated its effectiveness on class 1 aluminum welding in external tank production. More than three miles of welds were completed without an internal defect. Much of this success can be credited to automation developments which stabilize the process. Robotic manipulation technology is under development for automation of welds on the Space Shuttle's main engines utilizing pathfinder systems in development of tooling and sensors for the production applications. The overall approach to welding automation development undertaken is outlined. Advanced sensors and control systems methodologies are described that combine to make aerospace quality welds with a minimum of dependence on operator skill

State-of-the-Art Review and Synthesis: A Requirement-based Roadmap for Standardized Predictive Maintenance Automation Using Digital Twin Technologies

Recent digital advances have popularized predictive maintenance (PMx), offering enhanced efficiency, automation, accuracy, cost savings, and independence in maintenance. Yet, it continues to face numerous limitations such as poor explainability, sample inefficiency of data-driven methods, complexity of physics-based methods, and limited generalizability and scalability of knowledge-based methods. This paper proposes leveraging Digital Twins (DTs) to address these challenges and enable automated PMx adoption at larger scales. While we argue that DTs have this transformative potential, they have not yet reached the level of maturity needed to bridge these gaps in a standardized way. Without a standard definition for such evolution, this transformation lacks a solid foundation upon which to base its development. This paper provides a requirement-based roadmap supporting standardized PMx automation using DT technologies. A systematic approach comprising two primary stages is presented. First, we methodically identify the Informational Requirements (IRs) and Functional Requirements (FRs) for PMx, which serve as a foundation from which any unified framework must emerge. Our approach to defining and using IRs and FRs to form the backbone of any PMx DT is supported by the track record of IRs and FRs being successfully used as blueprints in other areas, such as for product development within the software industry. Second, we conduct a thorough literature review spanning fields to determine the ways in which these IRs and FRs are currently being used within DTs, enabling us to point to the specific areas where further research is warranted to support the progress and maturation of requirement-based PMx DTs.Comment: (1)This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessibl

International Initiatives To Eliminate Corruption: Has Bribery Declined?

Bribery discriminates against honest companies by creating a barrier to entry in the form of a competitive disadvantage.  An important legal issue with significant implications is whether recent international anti-corruption laws have leveled the playing field for firms doing business abroad.  One of the first laws proscribing illicit payments to foreign public officials is the Foreign Corrupt Practices Act (FCPA), initially enacted by the U.S. Congress in 1977.  From its inception, the FCPA has been criticized for placing U.S. firms at a competitive disadvantage based on the fact that few countries outlawed bribery of foreign officials.  In the past ten years, several international treaties have been ratified that seek to criminalize bribery and eliminate the tax deductibility of corrupt payments made to foreign public officials.  This paper discusses anti-corruption laws and their effectiveness in creating a transparent business environment that discourages bribery.     

Student Use Of Technology In Class: Engaged Or Unplugged?

In recent years, there has been a great deal of discussion about the need for student engagement and a meaningful connection in the classroom. With the advent of cell phones, computers and the Internet, students are more connected to, and, at the same time, more disconnected from each other than ever before. We are living in the age of exponential change and technological convergence where forms of technology speak to each other. The omnipresent cell phone is a mini-computer and according to futurist Ray Kurzweil, “What now fits in your pocket 25 years from now will fit into a blood cell and will again be millions of times more cost effective.” (Greene, 2010) A survey of 211 undergraduates was conducted in an effort to determine whether student use of technology in the classroom enhances engagement or encourages disconnection. The results are discussed and suggestions are proposed

Monitoring E-Mail In The Workplace: Privacy Rights And Employer Responsibilities

Two important legal issues with significant implications for both employers and employees are whether employers have a right to access their employees’ e-mail correspondence and whether employers should monitor their e-mail systems.  Many people assume that e-mail messages sent and received at work are afforded the same legal protection from invasion of privacy afforded traditional letters.  This assumption could not be further from the truth. Privacy law, case law, and Title VII responsibilities are discussed.  Suggestions are made for procedures employers should follow to ensure the proper use of e-mail in the workplace

Creating a Reading Culture in an Academic Library

Aliteracy is becoming a growing concern on college campuses, including East Tennessee State University (ETSU). Several years ago, a colleague emailed the librarians at Sherrod Library an article from the online edition of the Washington Post (Weeks 2001) about a graduate student at Park University in Kansas City who was making it through school by skimming texts, drawing information and themes from dust jackets, watching television, and listening to audio books. Jeremy Spreitzer, the focus of the Washington Post story, represented the growing number of students in the United States who are aliterate. After discussing this article at our faculty meeting, we came to the conclusion that there were a number of students on our campus that fit this description, and that the library must be creative in encouraging students to cultivate a lifelong reading habit

Development of Helicopter Flight Path Models

The objective of this paper is to present general techniques for simulating helicopter flight trajectory response. During flight the pilot manipulates the controls either to trim the helicopter for steady flight by balancing the external forces and moments or to produce a desired maneuver by controlling the unbalance of these forces and moments. Discussions of the physical phenomena involved with the aerodynamics of the rotors and fuselage are given in [1] through [3]. The simulated control function will be composed forward-aft cyclic, lateral cyclic, pedal, and collective. This control will be represented by the vecto

Confronting the Limits of Dialogue: Charlottesville, 2017

Chapter 3: Confronting the Limits of Dialogue: Charlottesville, 2017 in Libraries Promoting Reflective Dialogue in a Time of Political Polarization. ISBN 978-0-8389-4652-

A Preliminary Abundance Estimate Of An Atlantic Sturgeon (Acipenser Oxyrinchus Oxyrinchus) Contingent Within An Open Riverine System

Abundance estimates are essential for fisheries management, but estimating the abundance of open populations with low recapture rates has historically been unreliable. However, by using mark-recapture data modulated with survivability parameters obtained from analysis of acoustic telemetry data, more accurate abundance estimates can be made for species that exhibit these characteristics. One such species is the Atlantic sturgeon, for which abundance estimates were designated a research priority following precipitous population declines throughout the 20th century. We addressed this research need in the Saco River Estuary (SRE), a system where the Atlantic sturgeon has been extensively studied using mark-recapture and acoustic telemetry methods since 2009. These data were analyzed using Bayesian analysis of a Lincoln-Peterson estimator, constrained with parameters from a Cormack-Jolly-Seber model, to provide an initial abundance estimate for the system. The resulting estimate indicated that approximately 3 299 (95% Credible Interval: 1 462–6 828) Atlantic sturgeon utilize the SRE yearly, suggesting that the SRE provides critical foraging habitat to a large contingent of the species within the Gulf of Maine. The present study demonstrated the method utilized herein was effective in generating a reasonable estimate of abundance in an open system where recapture events are rare, and therefore may provide a valuable technique for supplying initial estimates of fish abundance in additional systems that display similar characteristics

Autologous Chondrocyte Implantation: Scaffold-Based Solutions

Autologous chondrocyte implantation is a surgical technique utilized for repair of articular cartilage defects. The originally described technique for autologous chondrocyte implantation involves applying a liquid suspension of the cultured chondrocytes to a cartilage defect and sealing the defect with a periosteum or collagen patch. Scaffolds for housing chondrocytes were introduced to allow for increased ease of delivery and application, to avoid leakage of chondrocytes out of the defect, and to allow for an implant that more closely mimics the non-uniform tissue architecture of healthy articular cartilage. In this chapter we describe the design, clinical outcomes, and commercial availability of various scaffolds reported in the clinical literature for autologous chondrocyte implantation