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The dawn of next generation robots and systems era which is quietly emerging, requires miniaturized and integrated sensors, actuators, and entire microrobots. One of the defining characteristics of these microsystems is their multiscale nature, e.g., the span of their size, features, and tolerances across multiple dimensional scales, from the meso to the micro and nanoscales. Another defining characteristic is the need to reliably integrate heterogeneous materials via assembly and packaging, in a cost-effective manner, even in low quantities. Thus, it is argued in this paper that cost-effective manufacturing of complex microsystems requires special precision robotic assembly cells with modular and reconfigurable characteristics. This paper presents recent research aimed at developing theoretical underpinnings for how to construct such a manufacturing platform. M³ is a multirobot system spanning across the macro-meso-microscales and specifically configured to package. The M³ robots are systematically characterized in terms of quasi-static precision measures and assembly plans are generated using kinematic identification, inverse kinematics and visual servoing. The advantage of our approach the fact that high assembly yields for our system are a consequence of a set of so-called precision resolution-repeatability-accuracy (RRA) rules introduced in this paper. Experimental results for packaging of a microelectromechanical systems switch are provided to support our findings. [ABSTRACT FROM AUTHOR]

Lung surfactant serves as a protective coating when adsorbed on particle surfaces, so its removal or rate of removal in vivo may affect expression of mineral cytotoxicity. Removal of phospholipid surfactant components from the surface of mineral particles ingested by alveolar macrophages (AM) was measured using fluorescence microscopy. Dipalmitoylphosphatidylcholine with a fluorescent label (BODIPY ) substituted for C1-C4 on the second acyl chain (DPPC*), was mixed with dioleoylphosphatidylcholine (DOPC) to coat respirable quartz and kaolin particles. Fluorescence from quartz or kaolin particles of 3-4, 5-6 and 8-9 µm size decreased in intensity with increasing ratios of DOPC/DPPC* for the same DOPC concentration of 0.4 mg/ml. There was a direct correlation between fluorescence and residual phospholipid surfactant remaining on particles using phospholipase A2 (PLA2) digestion in a cell-free system, indicating that the presence of the fluorophore on DPPC did not hinder enzymatic recognition. Lavaged primary AM obtained from male Fischer rats were challenged in vitro with DOPC/DPPC* (10:1 mol:mol) coated particles at 50 µg particles/10[sup 6] cells. In contrast to the biexponential response seen in cell-free experiments, the rate of fluorescence decay from ingested coated quartz or kaolin particles over 7 days was monoexponential, with the same t[sub 1/2] (41 h) for each dust. This study suggests that the rate of phagolysosomal digestion and removal of the adsorbed surfactant is not a determinant of the different mineral-specific pathogenicities or toxicities of quartz and kaolin, although residual fluorescence remained on particles even after 7-8 days. [ABSTRACT FROM AUTHOR]