Development of software to control 8-motor elliptically polarizing undulators

Advanced Design Consulting developed control software entitled IDcontrol for its state-of-the-art Apple II insertion devices (ID). These IDs feature 8 controllable axes: four servo motors control the gap and taper of two main girders, and four servo motors control the photon polarization-state by manipulating four sub-girders. IDcontrol simultaneously positions all 8 axes with high precision in real-time using 0.1 micron linear encoders attached directly to the girders and sub-girders. Helical and Inclined Plane phase modes are supported with automated mode switching. Magnetic-field-correction- coil current and girder taper are adjustable as functions of gap, phase, and phase mode. IDcontrol continuously monitors redundant encoder velocity and position data for maximal reliability, encoder failure detection, and damage prevention. Combined with ADC´s Graphical User Interface (GUI) entitled IDgui, IDcontrol manipulates the ID, provides user notification and automated recovery from errors, management of correction data, and isometric visualization of the ID´s girders. The functionality of both IDcontrol and IDgui has been demonstrated at MAX lab and the results will be discussed.