The uses of virtual reality3 December 2012
Technology originally intended to develop 3D environments for video games has been turned to an advantage in the UK nuclear industry, in which a mockup of a facility can help clarify and resolve planning and security issues. By Will Dalrymple
Close your eyes. From where you are right now, can you visualize how you would leave the building in an emergency? Where is the nearest fire extinguisher to you? Do you remember that other part of the site where you were last week: how would you get out of there in an emergency? For people experienced with a site, these basic questions are not difficult. But they only develop through experience. For a time, new starters don’t know.
Virtual reality can help with that. Real people use a joystick or keyboard and mouse to navigate through a model of a building or environment in a first-person view. This kind of activity has found phenomenal success in computer and console games such as the Activision Call of Duty series. As users navigate around the rooms, they become familiar with the space, as they would do in the real world. This was demonstrated to a Sellafield technical manager (who asked not to be named) in a previous job by a group of users of a virtual reality wargame that he helped develop. The game’s environment was based on a UK Ministry of Defence site on Salisbury Plain. When some of the users visited the site for real, they were able to orient themselves and navigate based entirely on their virtual experience.
He says that there are at least two reasons why mapping nuclear facilities in a similar way could help workers. The first is job planning in high hazard areas such as alpha-contaminated zones where access is restricted to those wearing air-fed-suits. An operative may typically be able to work for only two hours due to the heat stress involved. The virtual environment allows virtual access to the workface where tasks can be discussed and uncertainties removed prior to making the actual entry. Second is the building induction course that nuclear workers undergo prior to be allowed to work in and around a particular building. Passively following an escort around is not a particularly good way to learn an environment, he says; one learns by making mistakes, by relying on one’s own knowledge. Mistakes can be made in the virtual environment with no detriment to the individual or the environment.
However, his current work at Sellafield goes beyond site familiarization and becomes a tool for collaborative work.
“We have this facility that we are planning to rearrange so that plant operatives go through it carrying equipment whilst wearing an air suit, pass through a shower facility, gates, go around corners, through doors, and then leave at the end of their shift. Rather than building a mock-up [the expensive way],we found that if we we walked them through the virtual environment, we remove ambiguity. We can then incorporate their knowledge from the start (‘put this bit here, it is more convenient’; ‘don’t put the gate there’) without the need for rework.” He says the issue is the same when building a house; you can show people drawings, but they cannot form judgements about the space (as in ‘it doesn’t feel right’) until they can walk around inside the space.
“It becomes a stakeholder management tool,” the technical manager says. “It is a virtual test prototype that allows optimization cheaply. It means that you don’t have a conflict of interpretations. You can optimize the distance from the shower facility to the decontamination area where workers are wiped down; the ergonomics of how they exit the facility.”
So far, he has built a model of an offsite training facility (see screenshots), a research laboratory about to undergo decommissioning and a redundant plutonium production plant part-way through decommissioning.
His team used the game software Unity, and the environments were built by local engineering company FETL. “All that is needed is a map of the plant or facility with dimensions and a few tens of photographs—obviously this depends upon the size of the plant.” Each virtual environment starts with a shell of the rooms. These are drawn manually. Items within each room are then added; decor, such as fire extinguishers and wall pictures, is simply added by pasting in a photograph, he says. The cost of the simulation depends on the number of objects in the rooms and upon the degree of interactivity with the environment and objects. He has included information points, which if clicked show data associated with an object; objects that can be picked up and moved around the environment;and objects that can be removed by clicking on them. FETL have incorporated radiation into the environment by creating hot spots that glow red when approached. The models are stand-alone executable files (with supporting files) that can be copied, distributed and run a Windows PC without requiring additional software.
What he has not been able to do is to translate data from rotating laser scanners, which build up a 3D scale model of a real space, into virtual reality. “We gave [a contractor] a laser scan, and they tried to do an automated CAD environment area, and then slot that into the virtual world. But going from laser to CAD is not straightforward, because data from one point of view rarely captures the entire space; there are shadows. Scans from multiple points are required, or there is lots of manual labour required.”
One of the biggest issues in the project has been security. A photograph and a building plan are relatively easy to classify. A virtual environment is more difficult. It could be considered as a series of photographs but one needs to consider the aggregate information that is being presented. If a picture tells a thousand words, how much does a three-dimensional virtual environment express?
In video games such as Call of Duty, the player interacts not only with the virtual environment but also the creatures living in it; these adversaries are controlled by another part of the game architecture.
The virtual reality model of another part of the Sellafield site, the National Nuclear Laboratory’s central lab, has been populated by these automatic villains, and automatic defenders too. NNL, which is currently commissioning an upgrade to its radioactive materials lab, contracted US security simulation firm ARES International to use its Avert software to model the building and its security arrangements. The project began in May 2011.
The software aims to find the weak points in a building’s security by attacking it with a virtual force. “We built a toolset that allows linking a geophysical representation of the facility to a capability held in a library of data that represents the capabilities of barriers, detection devices, and weapons that avatars might have access to,” says Simon Johnson, ARES UK principal consultant.
“The model consists of a geophysical site, security features and detection devices, which are important because they set off an alert, and the guard force reacts. Our Avert system is fully automated. It uses simulation to allow attacks on the facility many thousands of times, and comes up with pathways, a way to gauge combat effectiveness,” says Johnson. The software simulates the battle plan of both attackers and defenders, based on their real so-called ‘concept of operations’.
Johnson says that the model is based on real-life data: “How long a certain type of door would resist attack by a crowbar. What might be an effective weapon in that weather. Can this line of sight be trusted; can you make the shot effectively. All of that analysis to be relied on has to be verifiable and validateable. So we access measured data, and we use subject-matter experts to see if the scenarios are credible. And we can’t rely on drawings; we have to walk the site, to make sure that the door is where it [the plan] says it is. And data changes all the time relative to capabilities. Cutting tools for accessing a fence can change over time; it is an ever-moving goalpost.”
Each analysis is scenario-driven, he says, which means, “You have to know your question before you ask the model.” The software identifies access pathways, the most likely access routes, and gives operational data to provide barriers to them. And it gauges the effectiveness of the guard force in simulated combat. The completed scenario can be re-run from the point of view of attackers, defenders and CCTV emplacements.
NNL decided to go down the route of security simulation because it felt that the “way in which security assessments were undertaken were very subjective in nature…At the sophisticated end of the spectrum you get a postulated scenario, a distance, a time to breach barriers to reach the objective. It is a single-path, single-objective strategy. It didn’t account very well for multiple start points, multiple routes, going for different attack and penetration styles, covert, or full offensive forces,” says Jeremy Edwards, NNL’s business manager, nuclear security, chemical, biological, radiological and nuclear, and resilience. He said that a chance introduction through the UK government to ARES in Washington DC was fortuitous timing, because “we were in a hiatus between building and commissioning, and there were changes in regulations, and there was a potential risk to the financial provision for security. We wanted a quantitative and objective means to validate our security solution, so we could have better dialogue with the regulator.”
Phase one of the central laboratory, which is currently operational, contains laboratories with gloveboxes and fume hoods for uranium, non-radioactive materials, and small quantities of plutonium. Its phase two project, which is expected to be commissioned in a few years, would involve creating alpha-radiation emitters (in particular, plutonium) to make for example MOX fuel test rods. (A proposed third phase would encompass constructing five hot cells for gamma-radiation emitters to carry out for example post-irradiation inspection of spent fuel).
When asked whether the Avert software has actually changed security arrangements, Edwards said that it had been beneficial: “the software has proved its worth, and is being adopted further.” In particular, NNL is planning to start training site guards using BluTrain, Avert’s sister product. It uses the same file as Avert for officers to walk through the facility and practice responses to simulated attacks. “The Blutrain product will allow us to have a dialogue with the protection force and allow them to observe and interact with security features. Although we are engaging with them we are not using that tool, although we are not far off from doing so,” he says.
This article first appeared in the November 2012 issue of Nuclear Engineering International magazine.