A LabVIEW approach to instrumentation for the TFTR bumper limiter alignment project

A project undertaken to measure the alignment of the TFTR (Tokamak Fusion Test Reactor) bumper limiter in relation to the toroidal magnetic field axis is discussed. The process involved the measurement of the toroidal magnetic field and the positions of the tiles that make up the bumper limiter. The basis for the instrument control and data acquisition system was LabVIEW. LabVIEW is a graphical programming system for developing scientific and engineering applications on a Macintosh. With LabVIEW, users create graphical software modules called virtual instruments instead of writing conventional text-based code. To measure the magnetic field, the control system acquired data from two nuclear magnetic resonance magnetometers while the toroidal field coils were pulsed. To measure the position of the tiles on the limiter, an instrumented mechanical arm was used inside the vessel. LabVIEW´s graphical programming environment provided an easy transition from engineering-design block diagram to a VI block diagram, which made for speedy development. It also provided for quick and painless online systems integration, which proved to be essential to the timely completion of the project