This paper presents a simulation study on the downscaling of multiple electrodynamic proof
mass actuators for the implementation of decentralized velocity feedback control loops on a thin
panel. The system is conceived to reduce the panel response and sound radiation at low
resonance frequencies. In the first part of the paper, the principal downscaling laws of a single
proof mass actuator are revisited. In particular, the scaling laws are given for: (a) the
fundamental natural frequency, (b) the damping factor, (c) the static displacement, (d) the
maximum current that can be fed back to the actuator, (e) the maximum stroke of the proof mass
and (f) the maximum control force that can be produced by the actuator. The second part of the
paper presents a numerical study concerning the control performance produced by decentralized
control systems with an increasing number of control units, which are scaled down in such a
way as to keep the total base surface occupied by the actuators constant. This study shows that
the control performance tends to rise as the number of control units is increased. However, this
trend is reversed for large arrays of small scale actuators since the gain margin of the feedback
loops tends to decrease with downscaling and incrementation of the actuators density.
