Recently, Adaptive Secondary Mirrors showed excellent on-sky results in the Near Infrared wavelengths. They
currently provide 30mm inter-actuator spacing and about 1 kHz bandwidth. Pushing these devices to be operated
at visible wavelengths is a challenging task. Compared to the current systems, working in the infrared, the more
demanding requirements are the higher spatial resolution and the greater correction bandwidth. In fact, the
turbulence scale is shorter and the parameter variation is faster. Typically, the former is not larger than 25 mm
(projected on the secondary mirror) and the latter is 2 kHz, therefore the actuator has to be more slender and
faster than the current ones. With a soft magnetic composite core, a dual-stator and a single-mover, VRALA,
the actuator discussed in this paper, attains unprecedented performances with a negligible thermal impact.
Pre-shaping the current required to deliver a given stroke greatly simplifies the control system, whose output
supplies the current generator. As the inductance depends on the mover position, the electronics of this generator,
provided with an inductance measure circuit, works also as a displacement sensor, supplying the control system
with an accurate feed-back signal. A preliminary prototype, built according to the several FEA thermo-magnetic
analyses, has undergone some preliminary laboratory tests. The results of these checks, matching the design
results in terms of power and force, show that the the magnetic design addresses the severe specifications.