Modular Integrated Monitoring System (MIMS) - Architecture and Implementation

Donald R Funkhouser, George W. Davidson, and Sharon M. Deland,

Albuquerque, New Mexico 87185

Abstract

Sandia National Laboratories

The MIMS is being developed as a cost-effective means of performing safeguards in unattended remote monitoring applications. Based on industry standards and an open systems approach, the MIMS architecture supports both data acquisition and data review subsystems. Data includes images as well as discrete and analog sensor outputs. The MIMS uses an Echelon LonWorks network as a standard means and method of data acquisition from the sensor. A common data base not only stores sensor and image data but also provides a structure by which dynamic changes to the sensor system can be reflected in the data acquisition and data review subsystems without affecting the execution software. The architecture includes standards for wide area communications between data acquisition systems and data review systems. Data authentication is provided as an integral part of the design. The MIMS also provides a generic set of tools for analyzing both system behavior and observed events. The MIMS software implements this architecture by combining the use of commercial applications with a set of custom 16 and 32 bit Microsoft Windows applications which are run under Windows NT and Windows 95 operating systems.

Introduction

The MIMS architecture takes a systems-level approach to developing an unattended monitoring system that allows continuity of knowledge of the material and activities being monitored without requiring a continuous on-site presence. Developed under the auspices of the US Department of Energy’s Office of Research and Development within the Office of Nonproliferation and National Security (NN-21), the MIMS (and its predecessor) has primarily been applied to several systems for International Remote Monitoring Programs which are guided by DOE’S NN-44. It is intended for other applications as well, several of which are in process.

Scope

The overarching research and development efforts for the MIMS program includes the development of specialized sensors (radiation, chemical), analytical tools, and data acquisition and review software. Using commercial tools and standards to integrate these development activities, the overall goal of the program is to develop a modular, flexible monitoring system that could be applied to a variety of applications. This paper will focus on the development of the data acquisition and review components together with the integration of commercial sensor and sensor network technologies.

System Architecture

The MIMS is a data acquisition and data review system designed for remote monitoring applications. As such, real-time response is not required as in a physical protection alarm system. Rather the data is acquired, saved, and protected until such time as it is retrieved and reviewed by an authorized entity to verify continuity of knowledge.

The high level concept of remote monitoring is for data to be acquired at a monitored site and then reviewed at some remote location rather than requiring an on-site inspection of the facility. As such, there are two

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This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United State Government nor any agency thereof, nor any of their employees, make any warranty, express or implied, or assumes any legal liabili- ty or responsibility for the accuracy, completeness, or usefulness of any information, appa- ratus, product, or process disdosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, mmmetxlation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessar- ily state or reflect those of the United States Government or any agency thereof.

DISCLAIMER

Portions of this document may be ilIegiik in eiectronic image produck Images lire produced from the best available original document.

major components of the MIMS. The Data Acquisition System (DAS) captures data at the monitored site and retains it until retrieved by an inspecting agency for review and analysis (Figure 1). The Data and Image Review Station (DIRS), typically located at a remote site, allows an authorized user to retrieve data and images from a monitored site and provides the operator a means to review and analyze that information. A single DIRS is able to retrieve data from multiple DAS sites over a variety of communications media. Conversely, a single DAS can download site data to multiple remote DIRS locations.

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Figure 1

The primary function of the DAS is to provide the means to acquire data from a number of different sources; the data being in many different forms. Typical data sources may include temperature, motion detection, position detection (such as for doors), radiation measurement, etc. Sensor manufacturers provide a variety of implementations for measuring a source. Video images are another source of data and are generated either by trigger or by schedule. A triggered image is generated only when an event of interest takes place such as the detection of motion. In order to accommodate as many different data sources as possible, the approach is to use an intelligent control network to create a common interface for generating and acquiring the data. A LonWorks network is used to fulfill this requirement and is discussed later.

The DIRS consists essentially of a computer system running the software necessary to access and retrieve data from the DAS, and to review and analyze the data that was retrieved.

Of primary importance is the necessity for the system to accurately reflect, end-to-end, the configuration of the sensor network at any given point in time. This is accomplished using a database structure which is common to both the DAS and DIRS systems to give ability to configure or modify an existing configuration of the sensor network for a specific site and have that configuration information dynamically reflected from the DAS to the DIRS. These modifications are retained in the database to provide an accurate historical record of the lifecycle of the sensor network

It is necessary that the software that resides in the DAS and DIRS be of a generic nature such that they may work with any configuration of the data sources at a site. A DIRS should work with any number of DAS systems without unique programming. This was accomplished by analyzing the MIMS functionality and designing the database so that site specific information is included in the database and not in the application software.

Commercially available hardware and software components are used wherever possible to reduce the cost of development. Standard interfaces allow efficient development of components by multiple sources.

Implementation

The DAS consists of the sensors or data sources, the sensor network, an interface between the network and the DAS computer, the DAS computer, and of course the software on the DAS computer. Configuration of the sensor network is provided by a tool which will be considered as part of the network and is discussed under that topic. Video images are supplied by an integrated Neumann DCM 14 Video System which actually uses a separate network to transfer image data to the DAS computer. A modem is attached to the DAS computer for external communications.

The DIRS consists of the DIRS computer, phone line modem, and software for the computer.

Sensor Network

An Echelon LonWorks network was chosen for the sensor network of the DAS. Echelon LonWorks provides a set of standards for network communication. LonWorks components are commercially available and are used in a wide variety of automated control applications ranging from use in buildings for environment, lighting, and alarm systems, to factory automation. Each “node” on a LonWorks network provides the interface between a data source and the network. Each node has a dedicated microprocessor which handles all network communications and allows for a custom application which can be used to preprocess data from the data source or allow multiple nodes to cooperate to perform functions.

Part of the LonWorks standards specify the way in which data from a node is represented. Sensor data is processed to be of a Standard Network Variable Type (SNVT). The SNVT defines how the data will be represented, that is, the type of measurement (such as temperature), the units of measurement (such as Celsius), and the resolution (such as tenths of a degree). This concept is carried beyond the network into the MIMS database on the DAS. This information is transferred to the DIRS which uses the SNVT information for the data to determine how to display it to the operator.

The LonWorks network management tool, iCELAN-G(iEC Intelligent Technologies), is used to manage the sensor network. The iCELAN-G software is installed on a separate Network Management System (NMS) computer which can be connected to the LonWorks network. A separate computer is used so that once the network is configured it may be removed and the function can no longer be performed on site. Network management functions include installation of nodes on the network, connection of messages between nodes, and configuration of node parameters. The iCELAN-G tool also captures system configuration information in the form of a graphical display which can show a bitmap representing one or more facilities at the site. On each bitmap icons are placed representing the nodes on the LonWorks network. When the network has been configured the network and system configuration information is transferred to the DAS computer database. This information is used on the DAS computer but is also passed on to the DIRS computer. In this way a dynamically configurable system has been created. The configuration originates on the NMS, is passed to the DAS computer, and then to the DIRS computer. Data changes are made to the database; however, the software applications which use the data do not change and can operate with any site configuration.

Sensor Network to DAS Computer Interface A separate hardware component referred to as the “data logger” is used to interface the LonWorks network to the DAS computer. The data logger is a commercially available component that collects and time stamps

sensor event messages as well as validates the message’s authentication signature. Data is retained on the datalogger’s hard drive until retrieved by the DAS computer’s data acquisition software.

Based on the PC-104 format, the datalogger is a low power device that can be put on an uninterruptabe power supply to maintain data acquisition for long periods in the event of power loss to the DAS computer.

Database

The database is the key component of the MIMS software. The database structure is shared between the DAS and DIRS computers. It was designed using object oriented methodologies to identify and organize the information to be stored in the database. The database can be described in three logical sections.

One section contains information describing the site and the configuration of the sensor network at the site. This includes information about (1) each of the sensor network components such as the network nodes, (2) the sensors attached to the nodes, and (3) the communication or “bindings” between network nodes. When the sensor network configuration changes, “version” information is saved in the database to allow the user to track changes to the network.

Another section contains information which is somewhat “static”. This is typically descriptive data such as information on the SNVTs and definitions of sensor “types”. This section also contains messages which are displayed for a given output of a specific sensor.

.The third section contains the actual event data that is generated by the sensors. Event data coming from sensor network nodes is organized around the standards applied to the SNVTs. Other event data is also stored in this section such as the image data from the Neumann DCM 14 Video system and internally generated “DAS’’ events.

DAS Computer and Software

The DAS computer is an Intel Pentium based personal computer using the Windows NT 4.0 operating system running three primary custom applications. The first communicates with the data logger transferring data to the DAS computer. The data is then stored in the database with any necessary preprocessing. The second application provides an operator of the DAS computer ways to examine the data that is already stored in the database. This is primarily a tool that is used when initially setting up the MIMS and later for verification or maintenance of the DAS on site. The third application serves as an intermediary to process requests for data from a DIRS. The DIRS supplies a request file which the application processes making a copy of the local data to be sent to the DIRS. At this time the DIRS has no direct access to the data on the DAS computer although development for networked access to the DAS database is in progress. The data transfer application also generates an authentication signature for the data being transferred.

The DAS computer utilizes two communications ports for servicing external connections. Onecomm port is attached to a phone line modem for data transfers. The second comm port is used for a serial connection to the data logger for obtaining temporarily stored sensor data collected from the sensor network.

Currently, data transfers occur only over telephone communications; however, investigations are underway to accommodate other media, such as satellite and cellular communications. Use of the Internet is also under investigation; however, the low-bandwidth and low-reliability of telephone communications to some existing and potential sites precludes the use of the Internet for data transfer. Windows NT’s Remote Access Services (RAS) software is used to provide the communications server function for incoming connections. An incoming call logs into an account set up on the DAS computer for DIRS access. User account features are applied to incoming calls such as password verification and file sharing privileges. The multi-tasking

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nature of Windows NT allows calls to be processed while other applications running on the DAS computer may be logging data to the database or providing a user display of the local data.

DIRS Computer and Software

The DIRS computer is an Intel Pentium based personal computer using the Windows 95 operating system. Windows NT will work just as well but Windows 95 was chosen as being more representative of the typical user. A phone line modem is attached to the computer.

Windows 95 Dial Up Networking services are used to provide the communications client function for outgoing connections. Multi-tasking of Windows 95 is used as well allowing a data transfer to be in process while the user reviews existing data on the DIRS computer.

The primary custom application on the DIRS computer is the Data and Image Review Station (DIRS) application. Integrated within this application is Data Analysis. The DIRS software allows an operator to set up and retrieve data from multiple DAS sites. Data and images from a site can be reviewed in various ways. A calendar displays days for which events are available and the severity of events. Events for a day may be displayed and filters such as a severity level or specific type of sensor can be applied to the data.

A separate application was developed to automate the transfer of data from a DAS to a DIRS. In addition to transferring data and images requested by the user, the DIRS transfer process determines from the DAS whether or not a change to the network configuration has been made. If so, the updated configuration information, including sensor and node information, graphics, screen locations of sensor icons, etc., is transferred to the DIRS.

Data Analysis

Further review of the data can be achieved in the Data Analysis software. The goal of the analysis sofhvare is to provide a set of analysis tools that aid the user in assessing continuity of data gathering, provide assurance that declared activities have occurred as expected, provide assurance that material has not been diverted, and determine the explanation for anomalous events. The development of analysis tools is taking a two-pronged approach: I ) development of a suite of baseline tools and 2) automated interpretation of events.

The suite of baseline tools is intended to allow the user to analyze the data by building histograms, making scatter plots, and applying basic statistical tools. These tools will allow the user to assess the operational history of the data acquisition system and to locate and characterize unusual events. Interpretation of those events is left to the user and his knowledge of activities at the site. An initial set of analyses has been implemented based on past analysis of International Remote Monitoring Program (IRMP) data. The set will be extended based on new data and interactions with IRMP participants. The current system allows for the application of qualitative criteria by allowing events to be categorized as Material Status, Material Alarm, System Status, System Alarm; quantitative criteria are addressed in a limited fashion by the use of thresholds to trigger data captured at the Echelon nodes.

Subsequent development will address automating the interpretation of events to help the user quickly assess data taken over long periods of time and would allow data summarization for users concerned with national or regional aggregations of data.

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Commun.;ations

The current implementation uses dial-up phone lines but other communications means such as the Internet or Satellite links could be easily implemented. Windows NT and Windows 95 networking features are used extensively. RAS is used on the DAS and Dial Up Networking is used on the DIRS.

Data Authentication

The LonWorks network provides authentication of communications between nodes on the network. The data logger and DAS computer are co-located and physically protected. The data from the nodes is stored in the database on the DAS computer with an indication of verification of the LonWorks authentication. The database that is transferred to the DIRS is signed before transfer and the signature is verified at the DIRS when received. An indication of the signature verification is stored in the database at the DIRS. The verifications is available to be displayed to the operator.

The authentication of images are provided by the Neumann DCM 14 Video system and are retained in the MIMS. An authentication signature for each image is generated at the camera module before transfer of the image to the DAS computer. The signature is carried with the image until it is authenticated by the image viewing software provided by Neumann Elektronik GmbH.

Summary

The MIMS is a suite of commercial and custom hardware and software components that provide data acquisition, review, and analysis capabilities for use in unattended remote monitoring applications. Based on industry standards and a systems-level approach to development, the system capitalizes on the use of applicable commercial products together with the plug and play capability of the sensor network and database to dramatically reduce, if not eliminate, the need for custom development for a specific site. Specifically, the system provides:

A distributed sensor network subsystem based on industry standards (LONWorksS) providing commercially available, plug and play hardware components, built-in authentication and communications protocol, and flexible topological support

A database structure, together with commercial network management software, that allows for dynamic end-to-end reconfiguration of the system to reflect and maintain an historical record of the modifications to the sensor network.

A multi-tasking capability for acquisition and storage of data, real-time display of raw data, and acquisition and storage of video images

An intelligent client-side and server-side data transfer mechanism

A variety of ways for viewing data and images using a graphical based user interface

A basic set of analytical tools to aid the user in assessing the operational state of the acquisition system and to locate and characterize unusual events

The development of MIMS has been and will continue to be an evolving process. Based on user input, system capabilities, such as analysis tools and distributed data access, will be enhanced to meet a continually evolving set of requirements.

Sandia is a multiprogram laboratory operated by Sandia Corporation, a Lockheed Martin Company, for the United States Department of Energy under Contract DE-AC04-94AL8500.