Nidhi Diwakar

nmdiwaka@ncsu.edu

B.S., Robotics Engineering, 2016
Worcester Polytechnic Institute

Research Focus: Active Particles

My research focuses on the rich and complex behavior shown by active particles (aka micromotors) in alternating current (AC) fields. Active particles are “self-propelling” microparticles that draw energy from their environment to power their motion. I am particularly interested in the development of the next generation of electrically powered engineered complex micro/nanomotors with dynamically programmable motion, and plan to work towards this by varying shape, morphology, coating, and stimulation of the particles.

In 2015, I had the pleasure of working with Koohee Han on the field-driven assembly of soft microbot grabbers composed of magnetic microcubes. We developed a preliminary method for making motile, reconfigurable and self-folding chains, which possess a reversible bending capacity when actuated by an external magnetic field.

My goal for the next several years is to investigate the combined actuation and steering of active particles through the use of light and AC field effects. Light as an energy source is renewable and biocompatible with most organisms at a wide range of wavelengths – properties that are immediately more versatile than those of chemically-fueled motors. In addition, similar to AC electric fields, micromotor activity resulting from optical stimulation can be predictably controlled due to the direct relationship to well-defined parameters, namely, wavelength and intensity. We believe that substantial progress in the field of active particles can be made by effectively combining optical and electrical energy to power micromotors. Optically-driven active particles have been shown to perform controlled flocking, scattering, and translational behavior. AC electric fields have induced rotational effects and frequency-dependent switching. A multi-field optoelectronic micromotor system shows great potential for superior steerability and propulsion control.

A link to our Israeli collaborators and their very cool research: https://mnfl.technion.ac.il/

Publications

Han, K.; Shields, C.W., IV; Diwakar, N.M.; Bharti, B.; López, G.P.; Velev, O.D. Sequence-encoded colloidal origami and microbot assemblies from patchy magnetic cubes. Science Advances 2017. DOI: 10.1126/sciadv.1701108.