Techniques for CAD reconstruction of 'as-built' environments and application to preparing for dismantling of plants

Electricite de France is using CAD-generated numeric geometrical models to simulate maintenance operations and enable optimizing maintenance procedures. These models are also used to program the machines or robots for certain servicing procedures. They are used in the operator interfaces for robot control, and provide the operator with virtual cameras or enable generating specific information (such as virtual force feedback). Even more recently, CAD models have been integrated in what is known as 'virtual reality' software, giving the operators a sensation of 'immersion' in a virtual universe. Depending on the need and on the type of results expected from the simulations, one needs more or less precise models of the environment in which work will be performed. EDF is using several techniques to get 'as-built' models of the environments. This article describes the SOISIC system, which is a 3D laser sensor widely used for environment data acquisition, associated with 3Dipsos software, for CAD model reconstruction. These techniques, and the applications subsequently developed formaintenance applications, can be used in preparing and carrying out dismantling operations: 'as-built' CAD modeling of the installation can be used in the preparatory phase, providing plans, simulating the varioussteps, calculating waste volumes, helping in optimization of waste management, etc. These models can also be used during the actual dismantling process, to program the machines or robots used, or in the robot or machinesupervisory system. Some of the presented techniques have been used in a room in the Brennilis plant, which is currently being dismantled. (orig.)