Virtual projects at Halden

The Halden Reactor Project is a joint undertaking of nuclear organisations in 20 countries sponsoring a jointly financed research programme under the auspices of the Nuclear Energy Agency (NEA). The programme is renewed every third year. The three main research areas at the Halden project are fuels, materials and man-machine systems (MMS).

Advanced computer-based human system interface technologies are now being introduced into nuclear power plants to replace the existing interfaces. These developments can have significant implications on plant safety in that they will affect the overall function of the personnel in the system by: the amount, type, and presentation of information; the ways in which personnel interact with the system; and the requirements imposed upon personnel to understand and supervise an increasingly complex system.

The Halden MMS programme is intended to address the above issues by means of extensive experimental work in the human factors, control room design and computer-based support system areas. The work is based on experiments and demonstrations carried out in the experimental facility HAMMLAB. Pilot-versions of several operator aids are adopted and integrated to the HAMMLAB simulators and demonstrated in a full dynamic setting. The Halden virtual reality (VR) laboratory has recently become an integral and important part of the programme.

Halden research facilities

HAMMLAB was established in 1983 to serve as the main environment for performing realistic experiments within the MMS research area.

HAMMLAB's NORS full-scope simulator is based on the Loviisa nuclear power plant in Finland. Recently HAMMLAB has been equipped with two more advanced full scope simulators, one Swedish BWR-type called HAMBO and a Westinghouse-type PWR called FRESH. The facility has three major functions:

• Process operation. In the control room, operators (test subjects) monitor and control the simulated processes in normal and disturbed plant conditions.

• Experimentation. In the experimenters' gallery, experiments are set up, monitored and controlled, and a database is collected during experiments consisting of human performance measurements as well as data from the control room operation and the process itself.

• Evaluation. Results from the experiments are analysed using various statistical techniques.

The studies being performed in HAMMLAB are of different size and complexity, ranging from large-scale human factors experiments to small-scale studies and tests. The requirements therefore vary considerably, and a flexible infrastructure is necessary.

The current control room is equipped with two operator stations and one supervisor station. A large interactive overview display has also been introduced in HAMMLAB. Because these devices are being introduced in many control rooms, the content of such overview displays must be investigated.

A large human factors experiment requires careful preparation prior to the actual execution of the experiment, and a large period for data analysis after the experimental execution. The data collection phase - the actual execution of the experiment - requires the availability of advanced data recording equipment. Audio and video recorders, eye movement tracking devices, computerised data logs of various kinds, are widely used in addition to questionnaires and online expert commentary. HAMMLAB provides the researchers with advanced data recording equipment and everything is configured and operated from the experimenters' gallery.

Virtual reality centre

The Halden virtual reality centre (HVRC) is a complementary extension to HAMMLAB.

The activities in the HVRC are connected to on-going research at the Halden project, as well as to development projects for industry. The HVRC expands the possibilities to develop and evaluate new systems and methods for man-machine interface (MMI) design. VR is being used to guide designers and inspectors in cost effective control centre design development and evaluation, and to develop computerised training tools for outage maintenance and operational tasks.

Virtual mock-ups

As nuclear control rooms need upgrading, there is now an opportunity to initiate the redesign by applying VR technology. HVRC carries out "virtual mock-ups" where the end-users (the operators), engineers and managers - along with assistance of human factors specialists - can formulate the optimal solution for their new control room.

The possibility to actually "walk inside" the planned control room to evaluate and modify the location of desks, keyboards, monitors and control boards is a tremendous advantage. The final output from this exercise is a set of CAD drawings of the construction of the control room. The Halden project is using this approach in several nuclear control room redesign projects.

Decommissioning planning

An important part of the VR activity at Halden over the last few years has been on decommissioning planning. A major project has been for the Japan Nuclear Power Cycle Development Institute (JNC). Here, HVRC performs research and development using VR technology in JNC's decommissioning process at the Fugen plant. The aim of the technology developed at Halden is to minimise radiation exposure of the workers involved in the process of dismantling and also to provide an effective medium for communication with the public and authorities. There are several application areas for VR in decommissioning projects, such as:

• Planning of the work process.

• Planning the dismantling work.

• Training of staff participating in dismantling work.

• Preparing information for public acceptance.

• Administration and reporting.

Current MMS research

The MMS programme for 2002 is intended to address issues related to human factors, control room design, computer-based support system areas and system safety and reliability.

Control room engineering

One aim of control room design is to study how virtual environments as an extension of the control room can be applied to increase realism in HAMMLAB experiments and to support control room validation studies.

Another activity is MMI design, and a concept called task-based displays is being developed at Halden. A user test of a prototype was performed in 2001 - and based on the findings the concept will be further developed.

Advanced alarm systems are studied on both the FRESH and HAMBO simulators, and a report on alarm systems will be issued in 2002. A new version of the COAST advanced alarm system toolbox will be released. A desktop and a projected VR version of a training system will be created and experiments performed to compare the effectiveness of each system.

The concept of human-centred automation (HCA) is introduced to characterise automatic systems that are designed to support the operator in fulfilling the role he has been allocated. To ensure that automation is human-centred at least two demands should be fulfilled: the tasks allocated to the operator should not exceed what a human can be expected to handle; and secondly, the operator context should allow him to act efficiently by providing him with an adequate level of information, controls, and time. Two activities are carried out to study HCA: the experimentally based HCA programme; and the Function Allocation Method (FAME) programme - a simulator and tool development study.

Data from the HCA-2001 experiment will be analysed and reported, and work will start to integrate the results from all HCA experiments in a lessons learned report. The functional modelling tool FAME will be expanded and evaluated using HCA scenarios.

The human reliability work consists of analysing and reporting of findings from the 2001 experiment on teamwork and operator task management techniques. An experiment will be performed in order to find which factors influence performance recovery. Work on tools for performance measurement will continue in order to provide a theory on MMI performance and a set of computerised tools that make it possible to measure this concept reliably and efficiently.

Plant operational support

Work in this area addresses issues related to development and assessment of methods and systems for improving plant performance and improving operational safety. One of the activities is related to the TEMPO system (thermal performance optimisation), where the system's ability to perform data reconciliation and fault detection will be studied in a BWR pilot-installation as well as in initial tests for a PWR application.

Another activity is the integration of the event and transient classification system ALADDIN, and training of this system with data from the HAMBO simulator. The signal validation tool PEANO (see links below) and the alarm system COAST will be merged as well as adopted and integrated in HAMMLAB.

A study will also be carried out into how artificial intelligence methods can be used to extract in real-time process information from the background noise of the normal process instrumentation. The main objective here is to develop a "virtual instrument" for accurate feedwater flow measurements in nuclear plants. An experiment on the level of automation in procedures will be carried out. The computerised procedure system COPMA will be used in studies using example procedures from the HAMBO simulator, and procedure verification techniques will be integrated in the COPMA tool.

A VR visualisation tool will be developed to support managers and workers involved in planning decommissioning and outage activities. The tool will be used to perform a practical test, combining wearable computing technology and tools developed for VR-manikin walk-around and radiation visualisation for operator guidance in hazardous environments.

System safety and reliability

Work in this area addresses issues related to software engineering methods which can be used to enhance the dependability of software based systems, with emphasis on identifying cost effective methods for obtaining adequate safety. Particular emphasis is given to the use of automated, formal techniques in the production of code traceable to requirements.

Secondly, the programme aims at developing tools support for a combination of methods for total digital systems analysis, based on previous research activities on Petri nets, qualitative simulation, and structural induction proofs. Another research topic is to evaluate different methods that can be applied in a risk analysis of integrated systems where software constitutes a fundamental part.