This paper presents a bio-inspired digital nanoactuation device (DND) for applications to nano-precision digital manipulation of photons and biomolecules. The structures and principles of DND device have been inspired from those of the biological muscle actuator. The bio-inspired DND, composed of a digital actuator and a nonlinear mechanical modulator, purifies the stroke of the digital actuator in order to generate the high-precision motion required for nano-positioning of photonic or bio-molecule devices. We design and fabricate two kind of DNDs: one with a linear modulator (1-DND) and the other with nonlinear modulator (n-DND), both having an identical input and output strokes of 15.2 mu m and 5.4 mu m, respectively. In experimental study, n-DND shows the repeatability of 12.3 +/- 2.9 nm, superior to that of 27.8 +/- 2.9 nm achieved by 1-DND. We experimentally verify that the displacement purifying capability of the bio-inspired n-DND achieves nano-precision motion repeatability, applicable to photon and bio-molecule manipulation. (c) 2006 Elsevier B.V. All rights reserved.