  The performance of a ring of linearly coupled, monostable nonlinear
oscillators is optimized towards its goal of acting as energy
harvester---through piezoelectric transduction---of mesoscopic fluctuations,
which are modeled as Ornstein--Uhlenbeck noises. For a single oscillator, the
maximum output voltage and overall efficiency are attained for a soft
piecewise-linear potential (providing a weak attractive constant force) but
they are still fairly large for a harmonic potential. When several harmonic
springs are linearly and bidirectionally coupled to form a ring, it is found
that counter-phase coupling can largely improve the performance while in-phase
coupling worsens it. Moreover, it turns out that few (two or three) coupled
units perform better than more.
