Vitaliano Inglese

A software framework for developing measurement applications under variable requirements

A framework for easily developing software for measurement and test applications under highly and fast-varying requirements is proposed. The framework allows the software quality, in terms of flexibility, usability, and maintainability, to be maximized. Furthermore, the development effort is reduced and finalized, by relieving the test engineer of development details. The framework can be configured for satisfying a large set of measurement applications in a generic field for an industrial test division, a test laboratory, or a research center. As an experimental case study, the design, the implementation, and the assessment inside the application to a measurement scenario of magnet testing at the European Organization for Nuclear Research is reported.

Measurement-Domain Specific Language for magnetic test specifications at CERN

A Measurement-Domain Specific Language (MDSL) for test procedure definition, measurement tasks synchronization, and instrument configuration is proposed. MDSL is a formal language specially designed for a specific domain of measurement and test, aimed at specifying complete, easy-to-understand, -reuse, and -maintain applications efficiently and quickly. Owing to MDSL constructs capability of abstracting key concepts of the domain, the test engineer can write more concise and higher level programs in shorter time without being a skilled programmer. The MDSL has been applied to the specifications of superconducting magnet tests of the Large Hadron Collider at CERN.

Proof-of-principle demonstration of a virtual flow meter-based transducer for gaseous helium monitoring in particle accelerator cryogenics

A transducer based on a virtual flow meter is proposed for monitoring helium distribution and consumption in cryogenic systems for particle accelerators. The virtual flow meter allows technical and economical constraints, preventing installation of physical instruments in all the needed measurement points, to be overcome. Virtual flow meter performance for the alternative models of Samson [ http://www.samson.de (2015)] and Sereg-Schlumberger [ http://www.slb.com/ (2015)] is compared with the standard IEC 60534-2-1 [Industrial-process control valves-Part 2-1: Flow capacity-sizing equations for fluid flow under installed conditions (2011), https://webstore.iec.ch/publication/2461], for a large temperature range, for both gaseous and liquid helium phases, and for different pressure drops. Then, the calibration function of the transducer is derived. Finally, the experimental validation for the helium gaseous state on the test station for superconducting magnets in the laboratory SM18 [Pirotte et al., AIP Conf. Proc. 1573, 187 (2014)] at CERN is reported.

Performance Improvement of a DSP-Based Digital Integrator for Magnetic Measurements at CERN

An improved self-calibrating digital instrument for online flux measurements on superconducting magnets for particle accelerators prototyped at the European Organization for Nuclear Research (CERN), in cooperation with the University of Sannio, is presented. The new instrument reduces the online flux analysis time down to 4.00 mus within a resolution of 50 ns. Furthermore, the typical signal-to-noise-and-distortion ratio (SINAD) is significantly improved with respect to the previous version and to the instruments that are currently in use. Details about the design, online measurement principle, and results of the metrological characterization of the new instrument are provided.

A New Cryogenic Test Facility for Large and Heavy Superconducting Magnets

CERN has recently designed and constructed a new cryogenic facility for testing large and heavy superconducting magnets at liquid helium temperatures. The facility, erected in a large assembly hall with cranes capable of up to 100 t, provides a cooling capacity of 1.2 kW at 4.5 K equivalent, 15-kW LN2 cooling and warming capabilities for up to three magnets in parallel. The facility provides the required technical infrastructure for continuous and reliable operation. Test capabilities comprise electrical, cryogenics, vacuum and mechanical verification, and validation at ambient and liquid helium temperatures. A comprehensive survey and magnetic measurement system, comprising a hall-probe mapper, a rotating-coil magnetometer, a stretched wire, a translating fluxmeter, and a laser tracker, allows the detailed measurement of the magnetic field strength and quality on a large volume. The magnetic axes of the quadrupoles can be established within ± 0.2 mm at 1σ accuracy. The facility has been equipped with power supplies, three converters of ± 500 A/120 V, and six converters of ± 600 A/40 V, as well as the required energy extraction, quench protection, data acquisition, and interlocks for the testing of superconducting magnets for the FAIR project, currently under construction at the GSI Research Center, in Darmstadt, Germany. The versatile design of the facility, its layout, and testing capabilities complements CERNs other test infrastructures for large superconducting magnets. We report on the design, construction, and commissioning of the facility as well as the expected capabilities and performances for future tests of large and heavy superconducting magnets.

The CERN revamping project of the obsolete cryogenic control systems: Strategy and results

The cryogenic infrastructure at CERN was originated in the 1960s with the era of bubble chambers and the associated superconducting solenoids. Since then and especially with the construction of the LHC accelerator and its detectors, large and complex cryogenics plants have been installed to provide cooling power from 800 W to 18 kW at different temperatures down to 1.9 K, demanding high and distributed technical capabilities from the control systems. The size and the complexity of the dedicated cryogenics has required the adoption of the CERN standard control framework UNICOS in order to enhance ease of operation and maintenance, and to provide long-term availability. After the completion of the LHC construction, exploiting the gained experience, CERN has started the upgrade of several obsolete cryogenic control systems. This paper describes (i) the overall project challenges, (ii) the technical procedure used in order to meet the technological operational requirements in terms of installation constraints...

A two-domain real-time algorithm for optimal data reduction: a case study on accelerator magnet measurements

A real-time algorithm of data reduction, based on the combination of two lossy techniques specifically optimized for high-rate magnetic measurements in two domains (e.g. time and space), is proposed. The first technique exploits an adaptive sampling rule based on the power estimation of the flux increments in order to optimize the information to be gathered for magnetic field analysis in real time. The tracking condition is defined by the target noise level in the Nyquist band required by the post-processing procedure of magnetic analysis. The second technique uses a data reduction algorithm in order to improve the compression ratio while preserving the consistency of the measured signal. The allowed loss is set equal to the random noise level in the signal in order to force the loss and the noise to cancel rather than to add, by improving the signal-to-noise ratio. Numerical analysis and experimental results of on-field performance characterization and validation for two case studies of magnetic measurement systems for testing magnets of the Large Hadron Collider at the European Organization for Nuclear Research (CERN) are reported.

Surface Response-based Behavioral Modeling of Accurate Digitizers : a Case Study on a Fast Digital Integrator at CERN

A statistical approach to simulation in behavioral modeling for assessing dynamic metrological performance during the concept design of accurate digitizers is proposed. A surface-response approach based on a statistical experimental design allows operating conditions to be systematically and comprehensively explored, simulation to be optimized, and identification and validation uncertainty to be verified. An actual case study on the dynamic metrological characterization of a fast digital integrator for high-performance magnetic measurements at the European Organization for Nuclear Research (CERN) is presented.