The vessel will still be in a vacuum, an environment in which complicated electromechanical systems tend to block. For example, conventional lubricants change state and lose their lubricating properties, resulting in more friction. The friction could then provoke jamming and it could wear on the moving parts. In addition, when exposed to heat and a vacuum, components tend to release gas—a process known as outgassing, which often ruins a vacuum. To overcome such hazards, alternatives must be found.
A full-scale prototype of the measurement system, developed by ASE Optics Europe for Fusion for Energy. The in-vessel viewing system will use LIDAR technology, firing a laser beam onto a plasma-facing surface and collecting the reflected light. © Fusion for Energy
Left: A photo of damaged divertor blocks (from ITER prototype components) inspected by the in-vessel viewing system. Right: the system view + 3D metrology data of the same part. Details of damage such as tile swelling, melting and cracking can be clearly detected. © Fusion for Energy