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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.
81

A MULTICHANNEL DATA ACQUISITION SYSTEM BASED ON PARALLEL PROCESSOR ARCHITECTURES

Gelhaar, B., Alvermann, K., Dzaak, F. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / For research purposes on helicopter rotor acoustics a large data acquisition system called TEDAS (Transputer based Expandable Data Acquisition System) has been developed. The key features of this system are: unlimited expandability and sum data rate, local storage of data during operation, very simple analog anti aliasing filtering due to extensive digital filtering, and integrated computational power which scales with the number of channels. The sample rate is up to 50 kHz/channel, the resolution is 16 bit, 360 channels are realized now. TEDAS consists of blocks with 8 A/D converters which are controlled by one transputer T800. The size of the local memory is 4 Mbyte. Any number of blocks (IDAM = Intelligent Data Acquisition Module) can be combined to a complete system. Data preprocessing is done in parallel inside the IDAMs. As for 16 bit systems the analog antialiasing filtering becomes a dominant factor of the costs, delta sigma ADCs with oversampling and internal digital filtering are used. This produces an exact linear phase and a stop band rejection of -90 dB.
82

CIGTF Enhanced Precision Reference Systems

Lawrence, Robert S., Gregory, George, Stutz, Derryl, Sanchez, Jerry, Neal, Brent 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The 746th Test Squadron at Holloman AFB has developed and utilized the Central Inertial Guidance Test Facility (CIGTF) High Accuracy Post-processing Reference System (CHAPS). CHAPS is a multi-sensor navigation reference system used to evaluate position, velocity, and attitude performance of Global Positioning System (GPS), Inertial Navigation System (INS), and Embedded GPS/INS (EGI) navigation systems on large vehicles and aircraft. Reference data is processed post-test with accuracy ranges from a meter to sub-meter depending on the reference configuration and test environment (profile, trajectory dynamics, GPS jamming, etc.). The GPS Aided Inertial Navigation Reference (GAINR) system developed by the Air Force Flight Test Center (Edwards AFB) offered other utilization capabilities (test beds and post-processing time). The basic sensor assembly is an EGI navigation system. The data are post-processed with Multisensor Optimal Smoothing Estimation Software (MOSES). Incorporating CHAPS and GAINR capabilities generates a reference system with enhanced accuracy (sub-meter) in a dynamic GPS non-jamming/jamming environment. This paper will present the enhanced reference system combination of CHAPS/GAINR capabilities, characterization process and development methodology.
83

DESIGN OF A GIGABIT DATA ACQUISITION AND MULTIPLEXER SYSTEM

Berdugo, Albert 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Gigabits and hundreds of megabit communication buses are starting to appear as the avionic buses of choice for new or upgraded airborne systems. This trend presents new challenges for instrumentation engineers in the areas of high speed data multiplexing, data recording, and data transmission of flight safety information. This paper describes the approach currently under development to acquire data from several types of high-speed avionic buses using distributed multiplexer and acquisition units. Additional input data may include PCM, wideband analog data, discrete, real-time video and others. The system is capable of multiplexing and recording all incoming data channels, while at the same time providing data selection down to the parameter level from input channels for transmission of flight safety information. Additionally, an extensive set of data capture trigger/filter/truncation mechanisms are supported.
84

THE USE OF IEEE P1451.3 SMART SENSORS IN A DATA ACQUISITION NETWORK

Eccles, Lee H. 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / This paper describes the use of an IEEE p1451.3 Smart Sensor bus as part of a network centric data acquisition system. IEEE p1451.3 provides for synchronized data acquisition from a number of transducers on a bus. The standard provides for Transducer Electronic Data Sheets (TEDS) that the manufacturer can use to describe the function and capabilities of the sensor module. The standard also provides for TEDS where the user can store information relevant to a particular application. The information in these TEDS can be used to generate much of the information that is required to be able to process the data during or after a test. The use of this information to configure and operate a Network Based Data Acquisition is described.
85

NETWORKED DATA ACQUISITION DEVICES AS APPLIED TO AUTOMOTIVE TESTING

Mastrippolito, Luigi 10 1900 (has links)
International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The US Army Aberdeen Test Center (ATC) is acquiring, transferring, and databasing data during all phases of automotive testing using networked data acquisition devices. The devices are small ruggedized computer-based systems programmed with specific data acquisition tasks and then networked together with other devices in order to share information within a test item or vehicle. One of the devices is also networked to a ground-station for monitor, control and data transfer of any of the devices on the net. Application of these devices has varied from single vehicle tests in a single geographical location up to a 100-vehicle nationwide test. Each device has a primary task such as acquiring data from vehicular data busses (MIL-STD-1553, SAE J1708 bus, SAE J1939 bus, RS-422 serial bus, etc.), GPS (time and position), analog sensors and video with audio. Each device has programmable options, maintained in a configuration file, that define the specific recording methods, real-time algorithms to be performed, data rates, and triggering parameters. The programmability of the system and bi-directional communications allow the configuration file to be modified remotely after the system is fielded. The primary data storage media of each device is onboard solid-state flash disk; therefore, a continuous communication link is not critical to data gathering. Data are gathered, quality checked and loaded into a database for analysis. The configuration file, as an integral part of the database, ensures configuration identity and management. A web based graphical user interface provides preprogrammed query options for viewing, summarizing, graphing, and consolidating data. The database can also be queried for more detailed analyses. The architecture for this network approach to field data acquisition was under the Aberdeen Test Center program Versatile Information System Integrated On-Line (VISION). This paper will describe how the merging of data acquisition systems to network communications and information management tools provides a powerful resource for system engineers, analysts, evaluators and acquisition personnel.
86

INTRODUCTORY SYSTEM DESIGN OF THE ADVANCED SUBMINIATURE TELEMETRY SYSTEM

Dacus, Farron L., Hendrix, Steven P., Bouchez, Joseph J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / The Advanced SubMiniature Telemetry System (ASMT) with Wireless Sensor extension is an ambitious program aimed at incorporating modern wireless system and electronic design methods into a two way, miniature, low cost, modular, and completely software controlled wireless data acquisition system. The program was conceived and is sponsored by the U.S. Air Force SEEK EAGLE Office as a means of both lowering test cost and increasing test effectiveness. This article shall present the fundamental system design challenges of the program and how modern design methods can provide a new standard of cost effectiveness, mission capability, and high spectral efficiency.
87

ADVANCED SUBMINIATURE TELEMETRY: A NEXT GENERATION INSTRUMENTATION SYSTEM

Harrison, William D., Copeland, Frank S. 10 1900 (has links)
International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / In performing its mission, the Air Force SEEK EAGLE Office (AFSEO) conducts a wide variety of tests with heavy emphasis on open-air flight tests. As budget pressures drive a reduction in the number of test sorties, maximizing the amount of quality data from each flight test is of paramount importance. This paper describes an AFSEO effort to develop a low cost, intelligent, subminiature telemetry and sensor system based on modern commercial wireless technologies. The instrumentation system is completely self-contained and can be externally mounted, thus eliminating the requirement for extensive aircraft modifications and minimizing the need for specially instrumented test aircraft. The system will make maximum use of Commercial Off The Shelf (COTS) components to reduce cost and insure availability. MicroElectroMechanical Systems (MEMS) technology will be incorporated as the technology matures.
88

COMMERCIAL OFF THE SHELF DATA ACQUISITION SYSTEM FOR THE SPACE SHUTTLE SOLID ROCKET BOOSTER PROGRAM

Crawford, Kevin, Pinkleton, David 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The space shuttle has been flying for seventeen years and NASA plans to fly it for many more. To meet the requirement of supporting future flights, NASA has undertaken a Shuttle Upgrades Program to improve various shuttle components. The avionics on the solid rocket booster (SRB) is one of the areas being upgraded. To develop avionics hardware, the environments that they are to encounter during flight must be defined to a higher degree of fidelity than is currently available. This paper describes the effort to determine these environments via the use of a commercial off the shelf data acquisition system.
89

MIL-STD-1553 Data Acquisition System

Landry, Michael 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1989 / Town & Country Hotel & Convention Center, San Diego, California / The Range Commanders Council recently added a chapter to IRIG 106-86 which describes a standard for acquisition of MIL-STD-1553 traffic flow. A system has been developed which monitors bus traffic using the format described in the standard for encoding. In addition to bus data, PCM analog channels can be inserted into the telemetry steam. Due to the high bandwidth of the telemetry stream, real-time ground processing of the 1553 data is difficult. Therefore, a limited number of selective measurements taken from the bus traffic are available at fixed positions in the telemetry format for real-time monitoring of critical parameters. A discussion of hardware, software, encoding, and testing will be presented.
90

Parallel Distributed Processing of Realtime Telemetry Data

Murphy, Donald P. 10 1900 (has links)
International Telemetering Conference Proceedings / October 26-29, 1987 / Town and Country Hotel, San Diego, California / An architecture is described for Processing Multiple digital PCM telemetry streams. This architecture is implemented using a collection of Motorola mono-board microprocessor units (MPUs) in a single chassis called an Intermediate Processing Unit (IPU). Multiple IPUs can be integrated using a common input data bus. Each IPU is capable of processing a single PCM digital telemetry stream. Processing, in this context, includes conversion of raw sample count data to engineering units; computation of derived quantities from measurement sample data; calculation of minimum, maximum, average and cyclic [(maximum - minimum)/2] values for both measurement and derived data over a preselected time interval; out-of-limit, dropout and wildpoint detection; strip chart recording of selected data; transmission of both measurement and derived data to a high-speed, large-capacity disk storage subsystem; and transmission of compressed data to the host computer for realtime processing and display. All processing is done in realtime with at most two PCM major frames time latency.

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