Practical Considerations for Designing a Remotely Distributed Data Acquisition System

A Data Acquisition (DAQ) system has become to be used in the field of large-scale scientific experiments with the advance of information technology. Especially, in DAQ System for a high energy physics experiment such as ATLAS experiment at CERN, parallel processing using a large number of network switches enhances the efficiency of acquiring and analyzing experimental data. Additionally, a DAQ system has many-to-one simultaneous communication that gathers data generated by a large number of detectors into one computer for analysis. Properties of such communication can cause network traffic congestions and packet losses, thereby decreasing throughput. One solution for such problem is Data Center Bridging (DCB) technology used to establish lossless Ethernet networks. In addition, since event fragments in a large-scale DAQ system are transmitted using many network switches, the buffer size of a network switch is critical. This study focuses on the queue of the network switch of a DAQ system using DCB and the effects on system performance. The fairness and throughput of each flow in many-to-one simultaneous communication system were measured. We confirmed maximum performance was achieved when an average queue length in the network switch was small.

A system of computer programs and hardware was developed by the Instrumentation Branch of the Morgantown Energy Technology Center (METC) to provide data acquisition and control features for research projects at the site. The Automatic Data Acquisition and Control System (ADACS) has the capability of servicing up to eight individual projects simultaneously, providing data acquisition, data feedback, and process control where needed. Several novel software features - including a data table driven program, extensive feedback in real time, free format English commands, and high reliability - were incorporated to provide these functions.

Service-oriented architecture of adaptive, intelligent data acquisition and processing systems for long-pulse fusion experiments

Data collection and analysis is vital for evaluating the performance of any equipment or system. Though the methodology of collection, transmission, storage and retrieval varies in different scenarios, the basic components of the set-up remain the same. The Data Acquisition and Monitoring System evolved from the need for remote monitoring of facilities that did not have an independent reliable infrastructure to implement a full-fledged SCADA system. Back when IT infrastructure was prioritized for business communications within the limited bandwidth allocated, collection and transmission of process data through the available network infrastructure was a challenge. More so when there are concerns regarding the confidentiality of data being collected and transmitted. Individual facilities were provided with local instrumentation and controls for reliable operations. With the growing production rates, the focus generally goes for improving the processing facilities rather than reading, reporting or recording. Instead of an independent dedicated network for Supervisory Control and Data Acquisition system that mandate a huge infrastructural cost and dedicated skilled personnel, a pilot project was initiated with a minimum budget to test data transfer through existing communication network. Field transmitters were installed on Wellheads, Risers and Manifolds and Remote Terminal Units were provided to collect data from two platforms and to facilitate data transfer to the servers through existing microwave communication network with minimum field instrumentation. Considering bandwidth limitations and priority for business communications, servers in redundant configuration were placed strategically to ensure continuous data gathering. Pilot project was successful in providing reliable data and trends with minimum disruptions. Augmentation of DAMS network was envisioned to implement Digital Oil Field for monitoring multiple assets in real time. Implementation of Digital Oil Field continued with the addition of new field instrumentation and RTUs followed by server upgrades and integration of PLC based platform control systems to add four major producing platforms to the Data Acquisition and Monitoring System through existing microwave communication network. Upon successful commissioning, it was possible to gather data from various wellheads, process equipment and other independent meters for remote real time monitoring and analysis through user friendly HMI screens and customized dashboards to manage multiple assets effectively, improving performance evaluation, safety and reliability of operations.

The Boeing Company is designing, developing and manufacturing the Core Stage and Avionics for NASA's heavy lift rocket, the Space Launch System (SLS), which will support missions beyond low earth orbit for the first time since the Apollo days. On the SLS vehicle many sensors are selected and used to provide critical information for testing, ground operations, and vehicle flight environments. Appropriate data acquisition systems that can interface and process the selected sensors is important to the success of the program. In this program, multiple data acquisition systems are used to interface with sensors at various development stages of the SLS vehicle, and at different sensor criticality levels. These phased configurations of data acquisition classes and complexity range from gathering sensor data during system level testing at Stennis Space Center (SSC), to transmitting flight information after liftoff at the Kennedy Space Center. One challenge that engineers are faced with pertains to how the data acquisition system is defined prior to understanding the quantity and type of sensors required for the application. This paper focuses mainly on the SLS flight system and provides a general overview of the system architecture. The paper also addresses the strategy used to define the data acquisition system, along with the methodology for selecting data acquisition cards that fit with the application.

A data acquisition system is required to interpret the electrical signals produced by radiation detectors when a gamma ray, neutron or other radiation type interacts with it. The data acquisition system can take on many forms to match the wide variety of radiation detector types available and the different ways in which the signals from these detectors can be processed to give information on the detected radiation. First presented is a detailed overview of a variety of analog data acquisition topologies ranging from simple radiation event counters through to pulse shape discrimination. A comparison is then made with the digital counterparts of these data acquisition topologies, highlighting the relative merits and shortcomings of both analog and digital implementations. Next, the important factors relating to how data is processed, stored and transferred through different stages of a data acquisition chain is discussed and suggestions given on how to avoid bottle-necks and ensure balanced data flow throughout the system. Also discussed are the key challenges associated with the design and configuration of data acquisition systems for active interrogation (AI) environments such as dealing with the high event rates, capturing the time development of active radiation signatures, and techniques for working with pulsed interrogating sources.

Event driven high speed data acquisition with IEEE 1588 synchronization for long pulse operations of Indian Test Facility for ITER DNB

The Simons Array upgrades the POLARBEAR experiment, which measures the cosmic microwave background from the Atacama Desert in Chile, with three newly developed receivers. Each receiver has 7,588 transition-edge sensor bolometers with a raw data rate of approximately 20 MB/s. This significantly increased data rate required us to develop a new data-acquisition (DAQ) and data-management system. As the network bandwidth from our observatory to our data-storage sites outside Chile is not high enough to send all the raw data, we compress the raw data on-site. The expected yearly compressed data rate is approximately 60 TB from each receiver. We have also developed a new housekeeping DAQ system. The new housekeeping DAQ system is a distributed system to handle the various newly added monitoring systems and to better understand our instruments and environments. Those data can also be fetched by another module for real-time monitoring of our instrument from all over the world with latencies on the order of minutes. We deployed the first receiver in late 2018 and started the commissioning of the DAQ system. The DAQ system has been working without significant problems and already accumulates a considerable amount of the new receiver data from the commissioning observations. In this presentation, we summarize and report the status of the new systems.

The ghost imaging is a new field in the research of the quantum nature of light. The long-distance reflective ghost imaging experiment with thermal light is suit for remote sensing with a high practicability. A real-time data acquisition (DAQ) system is presented for the experiment. In the setup, the light from source is separated into signal beam and reference beam. The signal beam which illuminates the target is collected by a bucket detector. The reference beam is directly captured by an area detector. The DAQ system employs a photo-multiplier tube as the bucket detector and a charge-coupled device camera as the area detector. The two detectors separately detect intensity fluctuations of two light beams. Meanwhile, the DAQ system implements high-speed and high-precision data acquisition and data processing to reconstruct the image of the target. The results of electronic tests and experiments show that the DAQ system satisfies the requirements of the experiment.

For accurate and optimized aerodynamic study on aerospace vehicle models in a wind tunnel, a high performance automated data acquisition (DAQ) system is required. To serve the purpose, a DAQ system integrated with model attitude control mechanism (robotic arm) has been developed at National Wind Tunnel Facility (NWTF), IIT Kanpur (India). The system has been developed using virtual instrumentation (LabVIEW) technique and PXI architecture which enhance the productivity and lower the cost through easy-to-integrate LabVIEW software and PXI modular hardware. This paper presents the implementation aspects of the developed DAQ system along with the system application example for optimized wind tunnel study on an aircraft model.

Long pulse (of the order of 1000 s or more) SST-1 tokamak experiments demand a data acquisition system that is capable of acquiring data from various diagnostics channels without losing useful data (and hence physics information) while avoiding unnecessary generation of a large volume data. SST-1 Phase-1 tokamak operation has been envisaged with data acquisition of several essential diagnostics channels. These channels demand data acquisition at a sampling rate ranging from 1 kilo samples per second (KSPS) to 1 mega samples per second (MSPS). Considering the technical characteristics and requirements of the diagnostics, a data acquisition system based on PXI and CAMAC has been developed for SST-1 plasma diagnostics. Both these data acquisition systems are scalable. Present data acquisition needs involving slow plasma diagnostics are catered by the PXI based data acquisition system. On the other hand, CAMAC data acquisition hardware meets all requirements of the SST-1 Phase-1 fast plasma diagnostics channels. A graphical user interface for both data acquisition systems (PXI and CAMAC) has been developed using LabVIEW application development software. The collected data on the local hard disk are directly streaming to the central server through a dedicated network for post-shot data analysis. This paper describes the development and integration of the data acquisition system for SST-1 Phase-1 plasma diagnostics. The integrated testing of the developed data acquisition system has been performed using SST-1 central control and diagnostics signal conditioning units. In the absence of plasma shots, the integrated testing of the data acquisition system for the initial diagnostics of SST-1 Phase-1 operation has been performed with simulated physical signals. The primary engineering objective of this integrated testing is to validate the performance of the developed data acquisition system under simulated conditions close to that of actual tokamak operation. The data acquisition is synchronized with a clock and trigger provided by the central timing system.

In this report we describe the new two-phase flow facility that has been constructed at Brown University. Included is the design philosophy that led us to select a blow-down, Freon tunnel as the means of studying the flow of a pure substance undergoing liquid-vapor phase changes. Each component is discussed from the initial design considerations, through sizing calculations, to actual system specifications. Special emphasis is placed on the instrumentation and automatic data acquisition and processing system. Finally a sampling of results obtained so far is presented. Section 1 gives the reasons for the construction of the facility and lists some of the uses and objectives of its operation. The reader can gain a good overview of the facility from Section 2 without a great deal of detail. In Section 3 we present the rationale for the particular design choices that were made and give details about the selection and sizing of all major components except the instrumentation. The latter subject is treated in Section 4 where we discuss the temperature and pressure probes, mass flow rate measurement, and other instrumentation. Section 5 is devoted to the test section proper where all the two-phase flow measurements and observations take place. The electronic data acquisition and facility control system is the subject of Section 6. Results on two-phase friction factors and flow pattern observations in a horizontal pipe are given in Section 7 along with the ranges of flow that have been covered so far. In capsule summary, the two-phase flow test facility is operational and has demonstrated a wide range of flow conditions from purely liquid to purely vapor through a variety of two-phase situations. Only horizontal flows have been studied so far, but the test section has been designed to operate in inclined positions up to fully vertical. The instrumentation performs very well as does the fully automatic control system. We believe the test facility is capable of yielding highly reliable and accurate data on two-phase flows which will be of great value in practice and in validating the various theories that have been put forth to describe this phenomenon.

We present a real-time data acquisition (DAQ) system for the long-distance reflective ghost imaging experiment which has broad application prospects in remote sensing. In the experimental setup, the light from a pseudo thermal light source is separated into signal beam and reference beam. The signal beam illuminates the target, and then the reflected light is collected by a bucket detector. In the mean time, the reference beam is directly captured by an area detector. In order to obtain the target image, the experiment requires high-speed and high-precision correlated data acquisition to collect the light intensity fluctuation in the signal beam and the reference beam. Furthermore, to reduce imaging time, real-time data acquisition is also required. The DAQ system consists of a photon-multiplier tube (PMT), a charge-coupled device (CCD) camera, a DAQ module and DAQ software. The CCD camera as the area detector connects to computer via Gigabit Ethernet. The PMT and a telescope compose the bucket detector which outputs signals to the DAQ module. The DAQ module sends acquired data to computer through universal serial bus (USB). The DAQ software collects the data and reconstructs the target image. The results of electronic tests and experiments show that the DAQ system satisfies the requirements of the experiment.

Research on high-speed data acquisition system of negative ion source breakdown

With the rapid development of the WoT, acquisition requirements to the data grow with each passing day. However, the existing data acquisition systems usually use the upload mode. Uploading data not only takes a lot of time, but also requires staff to continuously monitor on duty. Aiming at the problem of enterprise management data acquisition, a WoT-based enterprise management data acquisition and analysis system is constructed. The system obtains multiple monitoring data through the data acquisition module and integrates these data through the processing module, which can solve the problems of traditional data acquisition systems. In order to effectively fuse data, based on canonical correlation analysis (CCA), the multiple order statistics correlation discrimination analysis algorithm is proposed as a fusion strategy. Experimental results show that the fusion strategy based on CCA can effectively integrate monitoring data and accurately identify different characters.