(384i) Experimental and Theoretical Investigation of Actuation Schemes for Microrobots

I am a doctoral candidate in the Department of Chemical and Biological Engineering at the University of Colorado Boulder, seeking roles as an R&D, Process, or CFD/Multiphysics Simulation Scientist/Engineer in the semiconductor, medical device, or scientific equipment industries. I believe my strong technical background, my passion for mentoring the next generation of scientists and engineers, and my ability to approach projects holistically—considering both technical foundations and end-use applications—position me to build an impactful career.

My doctoral research has focused on the motion of active microparticle systems, or microrobots, for biomedical applications, under the guidance of Prof. C. Wyatt Shields IV and Prof. Ankur Gupta. I earned my B.S. in Chemical Engineering with a minor in Materials Science from Cal Poly Pomona, where I worked with Prof. Laila Jallo to i) fabricate a prototype transdermal patch for aspirin delivery and ii) develop a transdermal drug delivery model that combined molecular dynamics with a layered transport model to predict drug transfer through the skin.

Throughout my academic career, I have been fortunate to mentor five undergraduate students, receive the NSF LSAMP Fellowship and the NSF Graduate Research Fellowship, and publish in interdisciplinary journals such as Small, ACS Nano, and Soft Matter.

Current Research

Microrobots—functionalized microparticles actuated by external fields—are increasingly explored for biomedical applications, including cargo transport, tissue biopsy, and navigation through viscous biological fluids. However, the interplay between microrobot geometry, actuation mechanisms, and operating environments remains an underexplored but critical design consideration.

My doctoral work combines experiments and simulations to study microrobot motion under three actuation fields: chemical, magnetic, and acoustic.

• Chemical Fields: I developed theoretical mobility-based models to predict the motion of passive diffusiophoretic particles in engineered chemical fields and to examine the impact of real-time geometric reconfiguration on the motion of an active diffusiophoretic particle.
• Magnetic Fields: I fabricated and actuated magnetic helical microrobots with attached macrophages, a type of innate immune cell, to assess their ability to (i) transport macrophages through mucosal environments and (ii) promote pro-therapeutic macrophage phenotypes via drug elution from the robot. This work investigates the potential for biohybrid microrobots to access regions of the body inaccessible via systemic delivery and enhance adoptive macrophage transfers. In a separate project, I have also led work focused on reconciling theoretical predictions and experimental measurements for the gap distances of magnetic spherical surface rollers.
• Acoustic Fields: I used microparticle image velocimetry and multiphysics simulations to study frequency-dependent acoustic streaming generated by oscillating bubbles and sharp-edge microstructures. This work aims to enable the rational design of acoustically actuated microrobots with frequency-tunable motion.

My work helps to further our physical understanding of the mechanisms by which microrobots can be actuated. This will help to enable future application of microrobots in areas such as biomedicine and environmental remediation.

Research Interests

I am driven by my desire to combine theory and experiments to create new technologies based on foundational physics and engineering principles. I am interested in opportunities in semiconductors, scientific instrumentation, and medical device development. More broadly, I am passionate about designing products, measurement tools, microelectronic systems, etc., that provide value to companies, are useful to customers, and offer benefits to society.

Technical Expertise

Computational Fluid Dynamics and Multiphysics Simulations

My research has given me extensive experience in computational modeling and simulations:

• In my chemical actuation projects, I built a custom finite-volume solver in Python using first-order upwinding to solve coupled, transient, two-dimensional convection-diffusion equations. I also developed a rigid body dynamics code from scratch.
• I regularly use COMSOL Multiphysics for fluid dynamics and multiphysics simulations. In my magnetic actuation projects, I simulated low Reynolds number flows to calculate resistance tensors for helical and spherical microrobots.
• In my acoustic actuation projects, I implemented perturbation theory-based models to predict acoustic streaming flows and developed simulations that couple piezoelectricity, solid mechanics, and thermoviscous acoustics to predict acoustic fields in small-scale fluid chambers.
• I am proficient with Python’s scientific computing libraries and have developed custom animations, image analysis pipelines, and automated data processing routines.

Microscopy

I have hands-on experience with a wide range of microscopy techniques:

• Scanning electron microscopy (SEM) and Energy-dispersive X-ray spectroscopy (EDS) for microstructure verification.
• Confocal microscopy for video capture in micro-particle image velocimetry (uPIV) experiments.
• Total internal reflection fluorescence (TIRF) microscopy for quantitative surface-particle gap distance studies.

I also designed and built a custom and controllable magnetic field microscope capable of applying uniform, gradient, and rotating magnetic fields to microfabricated structures such as helical microrobots. In developing this microscope, I gained experience with optical components, electromagnet design, electronics, and designing custom 3D-printed housings. I collaborated with other users to improve usability, safety, and design. Incorporating feedback and continuously improving the system has been one of the most rewarding aspects of this project, as it allowed me to directly engage with “customers” (fellow researchers using the tool).

For image analysis and post-processing, I am skilled in ImageJ/FIJI, MATLAB’s Image Processing Toolbox, Python image processing libraries, PIV software (PIVlab), and particle tracking algorithms (Trackpy in Python).

Cleanroom & Microfabrication:

I regularly fabricate microstructures in the ISO 5 cleanroom at CU Boulder’s COSINC Fab facility. I have developed and optimized recipes using two-photon lithography, physical vapor deposition (sputter and e-beam), and oxygen plasma etching. I also gained experience troubleshooting and maintaining cleanroom equipment, including the Nanoscribe PPGT2 two-photon lithography system.