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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

FROM 0.5% TO 0.05%: ACHIEVING NEW LEVELS OF SENSOR ACCURACY IN AN AIRBORNE ENVIRONMENT

Sweeney, Paul 10 1900 (has links)
International Telemetering Conference Proceedings / October 18-21, 2004 / Town & Country Resort, San Diego, California / With recent improvements in data acquisition technology, it is now possible to use an FTI data acquisition system to measure analog signals with a total error from all sources of less than 0.05% - over an extended temperature range - and at high sample rates. This accuracy is better than one count of an old 10-bit system and includes non-linearities, initial errors (in gain, offset and excitation) and drift errors, simplifying the task of interpreting data acquisition system performance specifications. This paper looks at some practical steps taken to achieve this accuracy, from a hardware design and signal processing perspective. This leads to a discussion of implications for the FTI system designer, including: sensor and wiring specifications, sample rate, filtering specifications, and a discussion of implications for the data processing engineers.
12

ACHIEVING HIGH-ACCURACY TIME DISTRIBUTION IN NETWORK-CENTRIC DATA ACQUISITION AND TELEMETRY SYSTEMS WITH IEEE 1588

Grim, Evan T. 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / Network-centric data acquisition and telemetry systems continue to gain momentum and adoption. However, inherent non-deterministic network delays hinder these systems’ suitability for use where high-accuracy timing information is required. The emerging IEEE 1588 standard for time distribution offers the potential for real-time data acquisition system development using cost-effective, standards-based network technologies such as Ethernet and IP multicast. This paper discusses the challenges, realities, lessons, and triumphs experienced using IEEE 1588 in the development and implementation of such a large-scale network-centric data acquisition and telemetry system. IEEE 1588 clears a major hurdle in moving the network-centric buzz from theory to realization.
13

ARCHITECTURE FOR A NEXT GENERATION TELEMETRY AND DATA ACQUISITION BUS

DAWSON, D.M. 11 1900 (has links)
International Telemetering Conference Proceedings / November 04-07, 1991 / Riviera Hotel and Convention Center, Las Vegas, Nevada / During the requirements definition process for a new telemetry and data acquisition product, Veda Systems engineers had the opportunity to examine the requirements for the ideal bus architecture to support future needs. Design goals and requirements were solicited from major users in flight test, space ground station data monitoring and command applications, and C41, as well as Veda’s own engineers. The process resulted in a bus architecture design which could potentially set the standard for the next generation of telemetry and data acquisition systems. This paper outlines the design goals selected and the thought process that yielded the goals in an attempt to promote advancement of current bus design approaches and increased availability of standard architectures and operating environments.
14

Wireless data acquisition system for multi-phase electric power equipment

Goodsell, Douglas Andreas 2008 May 1900 (has links)
Industrial facilities that plan the shutdown of equipment for service have large financial savings compared to those managing unplanned shutdowns. To this end, a variety of algorithms have been developed and published in the literature that can monitor a machine's health and indicate when the machine starts to develop a fault. In order for such algorithms to be effective, they require raw data collected from machines. Often this involves the placement of accelerometers and other sensory devices for measurements of mechanical behavior. It is possible to extract much of the required information from the electrical signals of the equipment. This is normally a less expensive installation since one only needs access to the lines supplying electric power to the equipment. If these data acqusistion modules are accessible wirelessly, then one can monitor all the interfaced equipment from a central location. To successfully monitor such electrical equipment, a data acquisition unit is required that can sample on five or six channels simultaneously, depending on the switch gear configuration. This thesis details the development of an "endpoint" device that samples the required number of channels to monitor the electrical signals of industrial equipment, and interfaces to a wireless network. The hardware and software design of the "endpoint" is discussed in detail. Also, the software design of the server that receives the data from the "endpoint" is presented. The designed "endpoint" samples up to six channels simultaneously, at a rate of at least 8 kHz per channel, and a data resolution of 16 bits. The data are then transmitted wirelessly to a central server for processing. The system has been tested both in a laboratory environment and at an industrial environment. The desired specifications of the "endpoint" have been verified in both environments. Several "endpoints" have been assembled to form a network and have been tested in a laboratory setting. This work has resulted in the demonstration that an "endpoint" can be constructed using of the shelf components that is suitable for the continuous health monitoring of multi-phase electric machines through a wireless network.
15

DESIGNING AN AUTOMATIC FORMAT GENERATOR FOR A NETWORK DATA ACQUISITION SYSTEM

Kupferschmidt, Benjamin, Berdugo, Albert 10 1900 (has links)
ITC/USA 2006 Conference Proceedings / The Forty-Second Annual International Telemetering Conference and Technical Exhibition / October 23-26, 2006 / Town and Country Resort & Convention Center, San Diego, California / In most current PCM based telemetry systems, an instrumentation engineer manually creates the sampling format. This time consuming and tedious process typically involves manually placing each measurement into the format at the proper sampling rate. The telemetry industry is now moving towards Ethernet-based systems comprised of multiple autonomous data acquisition units, which share a single global time source. The architecture of these network systems greatly simplifies the task of implementing an automatic format generator. Automatic format generation eliminates much of the effort required to create a sampling format because the instrumentation engineer only has to specify the desired sampling rate for each measurement. The system handles the task of organizing the format to comply with the specified sampling rates. This paper examines the issues involved in designing an automatic format generator for a network data acquisition system.
16

CHALLENGES IN MONITORING MODERN INSTRUMENTATION NETWORKS

Blott, Michaela 10 1900 (has links)
ITC/USA 2005 Conference Proceedings / The Forty-First Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2005 / Riviera Hotel & Convention Center, Las Vegas, Nevada / The adoption of commercial off the shelf networks, such as Ethernet, FireWire and FibreChannel, within the avionics community has dramatically changed the architecture of avionics busses and instrumentation networks. Higher bandwidth links and unified interconnects simplify existing infrastructure and wiring. But due to their point-to-point nature, networking topologies are fundamentally different from systems built on legacy bus technologies such as CAIS and MIL-STD-1553. Switched networks and ring topologies pose various challenges for the implementation of network monitoring hardware, and affect the design of bus monitors and distributed data acquisition systems. This paper discusses some of these issues. In particular we address deployment issues, architectural choices such as pass-through versus tap approach, as well as handling of bandwidth requirements and complex communication protocols. We illustrate on the basis of a FireWire monitoring system how these obstacles have been overcome for one given application.
17

Role of a Small Switch in a Network-Based Data Acquisition System

Hildin, John 10 1900 (has links)
ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / Network switches are an integral part of most network-based data acquisition systems. Switches fall into the category of network infrastructure. They support the interconnection of nodes and the movement of data in the overall network. Unlike endpoints such as data acquisition units, recorders, and display modules, switches do not collect, store or process data. They are a necessary expense required to build the network. The goal of this paper is to show how a small integrated network switch can be used to maximize the value proposition of a given switch port in the network. This can be accomplished by maximizing the bandwidth utilization of individual network segments and minimizing the necessary wiring needed to connect all the network components.
18

Automatic Format Generation Techniques for Network Data Acquisition Systems

Kupferschmidt, Benjamin, Pesciotta, Eric 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / Configuring a modern, high-performance data acquisition system is typically a very timeconsuming and complex process. Any enhancement to the data acquisition setup software that can reduce the amount of time needed to configure the system is extremely useful. Automatic format generation is one of the most useful enhancements to a data acquisition setup application. By using Automatic Format Generation, an instrumentation engineer can significantly reduce the amount of time that is spent configuring the system while simultaneously gaining much greater flexibility in creating sampling formats. This paper discusses several techniques that can be used to generate sampling formats automatically while making highly efficient use of the system's bandwidth. This allows the user to obtain most of the benefits of a hand-tuned, manually created format without spending excessive time creating it. One of the primary techniques that this paper discusses is an enhancement to the commonly used power-of-two rule, for selecting sampling rates. This allows the system to create formats that use a wider variety of rates. The system is also able to handle groups of related measurements that must follow each other sequentially in the sampling format. This paper will also cover a packet based formatting scheme that organizes measurements based on common sampling rates. Each packet contains a set of measurements that are sampled at a particular rate. A key benefit of using an automatic format generation system with this format is the optimization of sampling rates that are used to achieve the best possible match for each measurement's desired sampling rate.
19

Data Acquisition Blasts Off - Space Flight Testing

Curry, Diarmuid 10 1900 (has links)
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / In principle, the requirements for a flight test data acquisition system for space testing (launch vehicles, orbiters, satellites and International Space Station (ISS) installations) are very similar to those for more earth-bound applications. In practice, there are important environmental and operational differences that present challenges for both users and vendors of flight test equipment. Environmental issues include the severe vibration and shock experienced on take-off, followed by a very sharp thermal shock, culminating (for orbital vehicles) in a low temperature, low pressure, high radiation operating environment. Operational issues can include the need to dynamically adapt to changing configurations (for example when an instrumented stage is released) and the difficulty in Telemetering data during the initial launch stage from a vehicle that may not be recoverable, and therefore does not offer the option of an on-board recorder. Addressing these challenges requires simple, rugged and flexible solutions. Traditionally these solutions have been bespoke, specifically designed equipment. In an increasingly cost-conscious environment engineers are now looking to commercial off-the-shelf solutions. This paper discusses these solutions and highlights the issues that instrumentation engineers need to consider when designing or selecting flight test equipment.
20

Migrating Airborne Instrumentation Systems from PCM to Network

Berdugo, Albert 10 1900 (has links)
ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / The majority of currently operating flight test programs around the world utilize PCM-based airborne instrumentation systems. Most instrumentation engineers are very comfortable with PCM-based data acquisition systems, and feel uncomfortable when talking about network implementations and the adoption of iNET. In order for these engineers to embrace this new technology, migrating from a PCM to network topology must be done in an evolutionary manner that provides for the preservation of capital investment while introducing new system concepts that enhance current instrumentation systems. This paper describes hardware components that enable instrumentation engineers to migrate their existing PCM-based instrumentation system to a network-based system. Several of these components are discussed to illustrate how they provide a controlled migration path to a network-based system. These components include time distribution, gateways, network data selectors, network switches, transmitters, transceivers, and recorders.

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