Automated real-time control of fluidic self-assembly of microparticles

Abstract

Abstract-Self-assembly is a key coordination mechanism for large multi-unit systems and a powerful bottom-up technology for micro/nanofabrication. Controlled self-assembly and dynamic reconfiguration of large ensembles of microscopic particles can effectively bridge these domains to build innovative systems. In this perspective, we present SelfSys, a novel platform for the automated control of the fluidic selfassembly of microparticles. SelfSys centers around a waterfilled microfluidic chamber whose agitation modes, induced by a coupled ultrasonic actuator, drive the assembly. Microparticle dynamics is imaged, tracked and analyzed in real-time by an integrated software framework, which in turn algorithmically controls the agitation modes of the microchamber. The closed control loop is fully automated and can direct the stochastic assembly of microparticle clusters of preset dimension. Control issues specific to SelfSys implementation are discussed, and its potential applications presented. The SelfSys platform embodies at microscale the automated self-assembly control paradigm we first demonstrated in an earlier platform.

Three-dimensional polymeric microtiles for optically-tracked fluidic self-assembly

“…9) evidence that neither the uncomplete SU-8 derivatization through the vapor-deposited SAM nor the slight asymmetry in layer thickness of some of the microtiles appear to significantly affect the SA dynamics of the microtiles. The latter depends significantly on the assembly technique and control strategy adopted, and is described in depth in [16].…”

“…The tailored fabrication process makes use of a thick Cu sacrificial layer to allow for the independent patterning of two superposed SU-8 structural layers, and can be upscaled to large substrates for the batch production of very large quantities of microtiles. This work is crucial toward in-depth experimental studies and analytical modeling of SA at microscale [16], which can benefit the expanding classes of advanced robotic and micro/nanomanufacturing technologies adopting SA as core paradigm.…”

“…They can by design coordinate laterally in water through hydrophobic interactions and shape matching independently of their vertical orientation to form close-packed, square lattice clusters. The microtiles feature a central marker aiding the real-time optical tracking and automated closed-loop control of their fluidic SA [16] performed by a dedicated platform [17]. The fabrication process makes use of copper as thick sacrificial layer and allows the wafer-level production of tens of thousands of microtiles in a single batch-in line with the massively parallel and scalable nature of SA.…”

Mesoscopic Self-Assembly: A Shift to Complexity

“…Reconfigurability consists instead in resetting the morphology of the system (Mattia and Otto, 2015). In static self-assembly, this is only possible by perturbing the potential landscape through changes in boundary conditions (Mao et al, 2002;Mermoud et al, 2012;Mastrangeli et al, 2014).…”

Characterization and validation of a novel robotic system for fluid-mediated programmable stochastic self-assembly

“…While intelligent building blocks can actively take part in the SA process and thus allow for distributed control approaches [2], [3], [4], [5], the SA process of passive building blocks can only be controlled through a centralized approach [6], [7], [8]. Centralized control approaches become 1.…”