For the generation of sinusoidal angular accelerations of very low distortion, different electrodynamic angular acceleration exciters with air-borne measuring tables (rotational air bearings) have been designed, developed, manufactured and tested. Using the combined effect of the electrical current flowing through the driving coil and the Lorentz force generating a torque, the non-linear distortion of the angular acceleration is kept below 2 %. Adaptation to different applications is made possible by two different exciters which have been newly designed, one of which is fitted with a rotational coil, the other with a flat coil. The latter variant is shown in the figure.
Angular acceleration exciter