Recent advances in soft materials, new fabrication schemes, and continuum actuation have supported the development of new micro-instruments and robotics. A fabrication scheme for miniaturized smart soft composite actuator has been proposed, which can generate a 390 μN force and achieve a large bending angle of 80°. Applications to grasping small and delicate objects with single and two finger devices have been demonstrated. The range of micro-devices developed also includes the design of a microscale piston, with a maximum dimension of 150 micrometers, fabricated with two-photon lithography onto the tip of 140 micrometer-diameter capillaries, as well as sub-millimeter microfluidic chips to deliver nanoliter droplets for liquid biopsy and in vivo drug screening. Related to these work, a microrobotic platform has been developed for the functionalization of fibers of diameters from 140 to 830 micrometers, with a patterning precision of 5 micrometers and an orientation error below 0.4°. This level of transfer precision would allow for the fabrication of micro-sensor arrays and electronic circuits to perform in situ biomarker detection and robot assisted intervention.
Floating magnetic microrobots for fiber functionalization
Principle of operation of the proposed micropiston
Micropiston-based compliant gripper
Schematic of the delivery sampling probe
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