HVRC VRdose is aimed at three main classes of end-user:
Radiation Protection use the software to model radiological conditions, optimise the placement of shielding to support work in specific areas of a nuclear facility, and evaluate the radiological consequences of the existence of different isotopes in a nuclear facility over time. Also use measured dose-rate values as an aid to modelling radiological conditions as accurately as possible.
Engineering uses the software to produce pre-job work descriptions for planned work with descriptions of activities and estimated durations. Use the software to optimise routes, work locations, waiting locations. Provide feedback to Radiation protection if necessary. Also use the software to support the production of post-work experience review reports.
Instructors use the software to communicate radiological conditions or a job description to staff or students. Instructors may have either (or both) a work planning or radiation protection background.
Radiation Protection and Engineering staff would normally collaborate to agree on the area in which work will take place and to optimise the positioning of shielding and other countermeasures related to the radiation exposure situation.
The software system comprises of the following main components
- VRdose Planner: Main tool with 3D workspace used to access, add, and manipulate data in the database, and produce reports
- VRdose Briefer: A dedicated 3D viewer for presenting scenarios prepared using the VRdose Planner in briefing situations
- An integrated database, in which data used by the VRdose Planner and Briefer is stored
Data is typically imported into the VRdose Planner from files and/or a database, and include:
- Detailed 3D geometry to visualise a nuclear facility or environment
- 3D geometry representing tools and equipment required to carry out a job
- Isotopic characterisation of sources (historical data, recent surveys, etc.)
- Dose-rate maps (if an external dose modelling system is used to produce dose maps)
- Actual dose-rate measurements
The VRdose Planner can be used to produce:
- Scenarios with job activities and trajectories that can be replayed as animations
- Dose graphs per worker or dosimeter in a scenario
- Pre-job work reports with a description of a scenario and the associated dose predictions
- Post-job experience review report given the entering of measurement data made when a scheduled job described in a scenario was actually carried out.
In order to define radiological layouts and job scenarios, information is imported from files, entered interactively through direct manipulation of 2D UI components or 3D objects using a mouse, or filling in forms with a keyboard. The user is supported in decision-making and evaluation of alternative scenarios through 2D charts and graphs and 3D plots of radiological conditions. Data entered is stored in a database and subsequent planning activities are thus able to use radiological conditions modelled previously, or expected as the result of planned work that is scheduled, as the starting point for planning further activities. Historical data for jobs that have been completed is available for use by instructors to support the training of staff, learning from past experience, while team leaders can brief workers on planned activities. The combination of graphs, 3D visualisation, and animation of planned work sequences make this a powerful communication aid.
Most data provided to model radiological conditions and to simulate job scenarios are entered interactively using an interactive 3D workspace. Objects in a layout and participants in a scenario are introduced to the workspace using a 3D drag and drop user interface, and some objects have parameters that can be manipulated directly or by entering values. In order to convey a sense of the dimensions of the layout and objects modelled, the user can display a grid with user-configurable spacing and also display the dimensions of selected objects, including routes/trajectories for objects or workers that move during a scenario. Free camera navigation is supported to enable the user to position a virtual camera, and target based travel techniques, including pre-defined and custom viewpoints and “go to selection” are supported.
3D Geometry Data Management
While the VRdose Planner can be used to model simple scenes using an empty floor situation to which source and shielding are added, detailed 3D models are normally added to the system database in a geometry interchange format. In the first version of the VRdose Planner, only the ISO VRML97 geometry data format is support for importing models to the Model Bank. Most CAD systems are capable of export 3D models in ISO VRML97 format, and third party geometry conversion tools and services are available for CAD systems that do not support direct export in this format.
In the Model Bank, we distinguish between Rooms (e.g. the nuclear facility itself) and 3D models that can be added to a layout by the user as part of a scenario, such as tools and equipment needed to perform a job. Rooms can be date-tagged in the Model Bank, so the system can thus determine which of multiple versions of a plant model to use depending on the date associated with a scenario and the date of a model version. In theory, this makes it relatively easy to integrate any existing 3D plant databases by importing date-specific plant models as “Rooms” into the VRdose Planner.
- Scenario: A collection of participants that perform actions over time in a room. A scenario always has a specified start and end date, and a status (draft, scheduled, completed etc.)
- Participant. An object that can be added to a room, thus participating in a scenario
- Room: A virtual environment in which a scenario takes place. It is typically represented as a single static 3d model representing a building. While static within the scope of a single scenario, there may be multiple variants of a room model representing the (planned or actual) state of the building at specific dates/times
- Layout: A static representation of the virtual radiological environment that represents a snapshot at a specific time that can be used as a reference scene configuration for new scenarios. Typically comprises of room + sources + shielding, but sometime other equipment left as the end state of a related job (e.g. a job is spread over several days represented by separate scenarios)
- Project: A collection of related scenarios and layouts, with additional common project meta-data (expected start date, expected end date, description, references)