Showing papers on "Data acquisition published in 1983"

Principles of measurement systems

Abstract: Part I: General Principles 1. The general measurement system. 2. Static characteristics of measurement system elements. 3. The accuracy of measurement systems in the steady state. 4. Dynamic characteristics of measurement systems. 5. Loading effects and two port networks. 6. Signals and noise in measurement systems. 7. Reliability, choice and economics of measurement systems. Part II: Typical Measurement System elements. 8. Sensing elements. 9. Signal conditioning elements. 10. Signal processing elements. 11. Data presentation elements. Part III: Speciaised Measurement Systems 12. Flow measurement systems. 13. Intrinsically safe measurement systems. 14. Heat transfer effects in measurement systems. 15. Optical measurement systems. 16. Ultrasonic measurement systems. 17. Gas chromatography. 18. Data acquisition. Answers to numerical problems. Index.

Automated laser interferometric ellipsometry and precision reflectometry

Abstract: A new opto-electronic ellipsometer operating on laser interferometric principles has been developed into an automated system based on a microprocessor. The latter performs the gain and offset calibrations and adjusts the various mode settings, followed by fast on-line data acquisition. Subsequently, data are processed via an interfaced minicomputer. The instrument is unique in providing absolute ellipsometric data. It permits perpendicular incidence ellipsometry, the handling of both vertically and horizontally mounted (liquid) samples, as well as precision reflectometry. Alignment is easily and quickly achieved because the signals are displayed on a cathode ray oscilloscope (CRO) screen. Some of the valuable features of this system are discussed in the light of results obtained in the visible spectrum.

Data acquisition system for large format video display

Abstract: A new and revolutionary approach to image processing eliminates the current limitations of video technology in terms of the analysis and processing of video images. A new data processing system "large format" allows the user of the system to process analog data with any desired degree of definition. The degree of resolution obtainable is limited only by the database and application with which the system is used. The preferred embodiment allows to segment the analogue data source (180), a map, a photograph, an x-ray, or any two-dimensional or three-dimensional object can be shown on a video system, a series of video images producing, when processed in sequence, accurate mosaic of the original image. In this way it is possible to view, measure and sketch the dimensions, shape or image of a rock, a tree or a pond on a photograph of a field measuring one acre in any desired purpose by the system user. The basic elements of the system are an XY coordinate positioning table (31, 32, 34, 36, 40), a microcomputer (90), a video camera (10) for gripping the segmented images, and an ordinary television set ( 100) to display an analysis of the segmented images that form the set of analog recording of the original image (180). The possible applications of the system are virtually limitless in the fields of agriculture, agronomy, animal husbandry, manufacturing, quality control, metereologie, medicine, and other similar areas and the possible forms of analysis are also unlimited, since the system can be used in the analysis of a surface, distance measurements, thermal characteristics or density, or to any object that can be importre electromagnetically put into images.

Method and apparatus for obtaining high accuracy simultaneous calibration of signal measuring systems

Abstract: Method and apparatus for high accuracy simultaneous calibration of electrical measuring systems wherein a calibration signal which has frequency spectra which interleave but do not interfere with the data spectra is injected into the electrical system during data acquisition to simultaneously correct for the response of the particular detection system. In a particular geophysical application, a calibration signal at a source system or receiver system, or both, is injected into each individual system as the data and calibration signals are measured so that an overall system response can be applied to the data signals in order to remove system response effects therefrom.

Aircraft data instrumentation and acquisition system

Abstract: An aircraft data acquisition system, especially a test data system, wherein a central control and acquisition computer receives data from a plurality of remote sub-units each comprising a power supply and a local computer and being connected via a series of input/output modules to respective sets of sensing transducers. Each input/output module comprises a circuit including a series of links which can be made or unmade to adapt the module for driving and/or processing the output of any of a wide variety of transducer types.

Device for transmitting signals by radio and cable between a central control and recording system and data acquisition devices

Abstract: In a data acquisition for seismic exploration, where the terrain is rugged or includes natural features which prohibit satisfactory radio communication between a central control and recording system and a plurality of seismic data signal acquisition devices, a relay element and a transmission cable are provided so that those acquisition devices which are not capable of satisfactory radio communication with the central control and recording system communicate instead with the relay element either by transmission cable or radio transmission and the relay element in turn communicates with the central control and recording system either by radio transmission or transmission cable, respectively.

Improvement of Measurement of Diffuse Solar Radiation

Abstract: To improve the accuracy of diffuse solar radiation data gained by ring shaded pyranometers, a new formula correcting for losses caused by the Hamburg ring has been derived. The formula has been validated by data sets of different time periods and from different pyranometer types, the latter with slightly modified constants. The correlation coefficients are always close to 0.80. For further improving the correction formula, the influence of the sky radiance distribution is to be taken into account. The so-called sky scanner was equipped for broad band measurements,and an appropriate data acquisition system was designed which uses a microprocessor to sample and store up to 1440 mean radiance values of the sky hemisphere. The reference data of diffuse solar radiation are delivered by a sun-following shade disk device with a shaded angle of 9.6°. A compact reference shade disk instrument has been built to be used for comparison with different kinds of shade ring devices used in the national networks in order to validate the transfered correction formula.

Data acquisition system for vehicles

Abstract: In the vehicle (1), an acquisition device (2) is mounted into which a cassette (3) having a data memory (22) can be inserted. On the other hand, the cassette (3) can be inserted into a data reader (4) in the office of the fleet depot in order to transmit the data from the cassette (3) to a computer (5). The data acquisition device (2) is constructed in such a manner that it is equipped with a multiplicity of transmitters (19) which check the various functions of the vehicle and supply data on these. To be able to correlate this data in time, a clock (23) with a time of day and date display is also arranged in the data cassette (3), which enables the data recorded in the data memory (22) to be correlated in time. Arranging the clock (23) in the cassette (3) instead of in the data acquisition device (2), as would be the obvious case, has the advantage that all acquisition devices of a fleet depot can be continuously checked for synchronicity via the computer (5) or via the data reader (4) without this requiring any manual or visual check.

Trajectory acquisition and monitoring system

Abstract: The system includes a plurality of mobile optical-electronic data acquisition stations for individual training on particular mobile targets. These stations are linked through an information exchange and distribution system with a common center cooperating with these stations in a real time configuration for purposes of generating data representing the trajectory of one or more targets on which the optical-electronic acquisition stations are trained.

Microcomputer-Based Data Acquisition for Tractors

Abstract: A low-cost, versatile data acquisition system for tractor performance variables was developed utilizing an AIM 65 microcomputer. The system measures drawbar pull and power, ground speed, wheel slip, fuel flow and engine speed and provides for printing these variables as well as recording on magnetic tape

Chlorophyll a fluorescence transients: a fast data acquisition system to facilitate in vivo measurements

Abstract: Characteristics of primary phases in chlorophyll a fluorescence transients based on room temperature in vivo measurement with a Plant Productivity Fluorometer (Brancker Model SF-10) can be greatly facilitated by coupling the instrument to a fast data acquisition system. The SF-10 was linked to a Multitech Industrial Corporation Microprofessor Microcomputer and further modified to ensure simultaneous onset of light activation and signal capture. Circuit diagrams and program listings are given in detail.This microprocessor system is capable of capturing signal changes over a minimum period of 200 milliseconds to a maximum of 6 seconds. Accuracy of recorded data is dependent on rate of change of the input signal and the recording time period. Acquisition and storage of 5000 points from zero to 300 milliseconds ensured clear resolution of Fo, I and D when played back over 120 seconds on a chart recorder. For routine use, the primary transient can be captured over 0-2 seconds and then replayed as an accompaniment to standard slower presentation of primary plus secondary transients. Coincidence of signal amplitude for Fp on both systems can then be ascertained while retaining adequate resolution of Fo and I.

Computer simulation of low-frequency electromagnetic data acquisition

Abstract: Computer simulation of low‐frequency electromagnetic (EM) digital data acquisition in the presence of natural field noise demonstrates several important limitations and considerations. Without a remote reference noise removal scheme, it is difficult to obtain an adequate ratio of signal to noise below 0.1 Hz for frequency‐domain processing and below 0.3 Hz base frequency for time‐domain processing for a typical source‐receiver configuration. A digital high‐pass filter substantially facilitates rejection of natural field noise above these frequencies; however, at lower frequencies where much longer stacking times are required, it becomes ineffective. Use of a remote reference to subtract natural field noise extends these low‐frequency limits by one decade, but the remote reference technique is limited by the resolution and dynamic range of the instrumentation. Gathering data in short segments so that natural field drift can be offset for each segment allows a higher gain setting to minimize dynamic range p...

Data Acquisition And Preprocessing Techniques For Remote Sensing Field Research

Abstract: A crops and soils data base has been developed at Purdue University's Laboratory for Applications of Remote Sensing using spectral and agronomic measurements made by several government and university researchers. The data are being used to (1) quantitatively determine the relationships of spectral and agronomic characteristics of crops and soils, (2) define future sensor systems, and (3) develop advanced data analysis techniques. Researchers follow defined data acquisition and preprocessing techniques to provide fully annotated and calibrated sets of spectral, agronomic, and meteorological data. These procedures enable the researcher to combine his data with that acquired by other researchers for remote sensing research. The key elements or requirements for developing a field research data base of spectral data that can be transported across sites and years are appropriate experiment design, accurate spectral data calibration, defined field procedures, and through experiment documentation.

Method and apparatus for simultaneously recording multiple FT-IR signals

Abstract: A method and apparatus for simultaneously recording multiple Fourier Transform Infrared (FT-IR) signals using an interferometer. The analog signals are coupled to switching means which is operable in response to a first control signal for synchronizing the operation of the interferometer and the control circuits and a second control signal for defining data acquisition intervals to direct the sampled data of the analog input signals over a circuit path including Sample and Hold and Analog to Digital Conversion circuits to a processor for storing the digital data corresponding to the analog input signals. The switching means is operated so that samples of the analog input signals are taken in sequence and stored in sequential storage locations in interleaved fashion. The processor is operable under program control to access the digital data so that all data samples for the same input signals are separated to produce an interferogram for each of the input signals. These interferograms can then be Fourier Transformed to produce spectra in the usual manner.

A Microprocessor-Based Data-Acquisition System for Stall/Spin Research

Abstract: Accurate data are necessary for the identification of aerodynamic parameters at high angle of attack and in spinning flight. Modern sensors and microelectronic devices are employed in a stall/spin data acquisition system that will be tested in a Schweizer 2-32 sailplane. This instrumentation package will use a quaternion-based ?strapdown IMU? algorithm to derive vehicle attitude from angular rate data, and it will use fault-detection logic to identify inflight sensor failures. Details of the system and flight test program are presented, together with results of preflight digital simulation analysis.

Data acquisition circuitry for use in computerized tomography system

Abstract: A digital acquisition system for use in a computerized radiation tomography system employs track and hold means associated with each channel of the radiation detector in the tomography system Each channel of the radiation detector is connected to a voltage follower transistor and resistor A signal from the voltage follower transistor and resistor is applied through a Butterworth filter and amplifier to a transconductance amplifier which provides a signal for application to a charge storage capacitor The capacitor is connected to the detector channel except during each limited period of time when the charge is held for measurement and conversion to a digital form The data acquisition system has fewer components, and the simplicity of the circuitry increases the circuit reliability

Real Time Diagnostic Data Acquisition System for the Doublet III Tokamak Fusion Experiment

Abstract: The Doublet III data acquisition computer system acquires, archives, and processes over three megabytes of data from each shot of the experiment. A shot lasts 1-2 seconds and occurs every 5-6 minutes with 50-100 shots/day. The data acquisition system has been configured to efficiently handle the increasing quantity of data as new plasma instruments are added (five megabytes within a year) and to provide interactive capability during operations. The configuration is a dual CPU system with a dual port disk and bulk core memory. One CPU is devoted to acquisition and archiving while the other CPU is for analysis and interactive use. This system has enabled improved shot-to-shot processing of plasma data thus providing guidance to the physics operations team. A planned upgrade of Doublet III will require data handling of over 20 megabytes/ shot.

VAX 11/780 Data Acquisition Facility at Triangle Universities Nuclear Laboratory

Abstract: Current features and hardware of the TUNL VAX 11/780 CAMAC data acquisition system are described.

Data acquisition system and methodology for high angle of attack parameter estimation

Abstract: A digital data acquisition system has been flight tested in a Schweizer 2-32 sailplane and the algorithms, designed for high angle of attack parameter identification, are described in this paper. The system is portable and self-contained. Inertial sensors are mounted in a strapdown unit. Two Kiel-probes are used for airspeed measurement. "Off-the- shelf" microelectronics components are configured to operate as a multiprocessing system. The on-board computing power is used to monitor the sensor and support system and to improve flight test effectiveness. The Estimation-Before-Modeling technique has been selected for parameter identification. A time history of a flight test maneuver that will be used in the estimation of the aerodynamic parameters is also presented.

Computerized Data Acquisition and Display in Anesthesia

Abstract: In a collaborative effort to investigate the impact of computer supported and centralized data acquisition and display in anesthesia on the quality of care and on the task performance of the anesthesist, such a system has been designed and this will be described A total of 32 primary variables can be handled After data reduction and feature extraction a maximum of 64 derived variables are stored on floppy disk every 15 seconds A variety of display formats are available showing subsets of all signals on two color displays in numerical or graphical form