An operator assistance system for beam adjustment of a cyclotron

The authors discuss a computer-based operator system for cyclotron operators. The main feature of the system is a visual display of feasible setting regions (FSRs) of adjustable parameters. The FSR, derived from constraints among these parameters, shows the valid ranges where set points can be adjusted. Search traces by the operator are superimposed on the same screen as an aid to the operator´s memory. In order to derive the FSR, first the cyclotron is modeled as a series of mappings of beam states, giving a conceptual description of the relation between beam states and constraints. Next, based on the model, the beam adjustment can be regarded as a search for the optimum mapping. This process is formulated as a nonlinear minimization problem; and its solution determines the FSR. Finally, to realize real-time display of the FSR, two methods which make the display response time shorter are proposed