Research/Projects
GHz Ultrasonic Imaging
GHz ultrasonic imaging and characterizing nematodes/C. elegans
GHz ultrasonic imaging of nematodes to quantify nematode populations within the soil. A 128-pixel by 128-pixel, 1.85 GHz monolithic CMOS-integrated ultrasonic imager was used to image nematodes in moist soil, air, and thin layers of water.
Geegah Inc., Ithaca, NY
Relevant links: IUS 2022 Nematode Differentiation, Microscopy and Microanalysis 2022, C Elegans Aging, IUS 2021 Nematode Visualization
Imaging soil health
Multi-modal GHz ultrasonic imaging of soil moisture, temperature, morphology, and nematodes simultaneously to monitor soil environment change. The imager was first calibrated with soil VWC% and temperature. Data acquisition over several days, recording events of nematodes coming near the imager, and identifying soil properties to optimize plant growth.
Geegah Inc., Ithaca, NY
In-situ monitoring of printed electronics ink
The first-ever in-situ imaging of 3D Printed Electronics (PE) ink delivery and drying while printing using a GHz ultrasonic imager. The reflected ultrasonic pulses measure ink parameters such as ink’s acoustic impedance and temperature at a sampling rate of up to 30 frames per second.
Geegah Inc., Ithaca, NY
On-chip microfluidics
A novel approach to monitor fluid flow, chemical reactions, and cells through acoustic impedance of materials. Demonstration of bonding transparent and opaque microfluidic channel substrate to the silicon wafer and visualization of on-chip microfluidics without a light source.
Geegah Inc., Ithaca, NY
Relevant links: Transducers 2023
Cells and tissue characterization
Demonstration of monolithic CMOS ultrasonic imager as a platform for visualizing cells and tissues at 1.8 GHz. Applications include real-time characterization of tissues without pre-processing and studying the mechanical properties of cells during growth and motility.
Geegah Inc., Ithaca, NY
Fluid Mixing
Visualization of instabilities formed during the mixing of miscible and immiscible fluids without the use of any dyes.
Geegah Inc., Ithaca, NY
Fluid Mechanics
Bubble Dynamics
Study of bubble impact in curved and tilted surfaces. Impact characteristics such as bubble radii and angle of impact were varied to observe bubble dynamics changing. Particle Image Velocimetry (PIV) was performed to compute vorticity, which was used to predict the bubble path during impact.
Bio-inspired Fluids Laboratory, Cornell University, Ithaca, NY
Drop Dynamics
Investigating the underlying mechanism of water ejection from the ear canal by performing experiments and developing a stability analysis. Glass tubes and 3D PDMS ear canals with varying canal diameter, water volume, and trapped air volume were tested at different acceleration rates. A theoretical model was modified from the Rayleigh-Taylor instability, which validated the critical acceleration (threshold for ejection) obtained from the experiments.
Bio-inspired Fluids Laboratory, Cornell University, Ithaca, NY
Relevant links: JFM, APS DFD acceleration induced water ejection 2019, PHYS.ORG EAR, Medium EAR, Science Alert EAR
Miscellaneous
Bifurcating 3D Printed Face Masks
A unique approach inspired by the complex nasal anatomy of animals to design 3D printable filters. The mask consists of features that reduces air gaps with the nose and the chin whereas the filter includes tortuous or bifurcating pathways to capture particles. This concept of focusing on the airflow turns to trap the particles can lead to the development of highly efficient air filters.
Bio-inspired Fluids Laboratory, Cornell University, Ithaca, NY
Airplane wing vs winglet comparison (FEM)
Study of differences in drag and lift forces generated at aeroplane wings with and without winglet at cruising speed using FEM. Simulations were performed in the SST turbulence model of CFD and the results are compared to that of the experimental and theoretical models. The simulation showed that the lift increased by 26.0% and the drag decreased by 74.6% for the winglet at cruising speed.
Mechanical Arm: 3D printing
Modification and 3D printing of The UnLimbited Arm 2.0 Alfie Edition. The 3D printed arm is comprised of phalanx, fingers, palm, forearm, pins, cuff, and jig. These are further supported by strings, elastics, and plastic for its functionality and strength. The fully mechanical arm was customized and handed over to a 12-year old girl Sabita.
CMDN, Kathmandu, Nepal
Relevant links: Report
Topological Maps: 3D printing
This project focuses on 3D printing maps which depicts a clear picture of a trail or a location. It acts as a miniature version of the exact location which can help the trekkers to compare the trails with the 3D maps and get a better idea of their pathway.
CMDN, Kathmandu, Nepal
Teaching experience
- BEE 4530 (Computer-Aided Engineering: Applications to Biological Processes: Capstone), Cornell University, Ithaca, NY Spring 2021: Undergraduate Teaching Assistant for Prof. Ashim K. Datta Topics include problem formulation and modeling of various applications to biological processes using COMSOL. Understanding the basis of FEM and FDM in engineering simulations and modeling a process including sensitivity analysis, validation, and solution convergence. Designed, graded assignments, and assisted 19 undergraduates with modeling in COMSOL.
- ECE 5960 (Piezoelectric Microsystems: Sensing, Actuation, and Physical Computing), Cornell University, Ithaca, NY Fall 2020: Undergraduate Teaching Assistant for Prof. Amit Lal Topics such as piezoelectric materials and transducers, wave generation, sensing, and micromechanical approaches for structure fabrication. The primary focus was to design FEM model related to wave propagation using OnScale for 12 graduate students.
- BEE 2600 (Principles of Biological Engineering), Cornell University, Ithaca, NY Spring 2019, Fall 2019: Undergraduate Teaching Assistant for Prof. John C. March Topics range from molecular principles of reaction kinetics and molecular binding events to macroscopic applications such as energy and mass balances of bioprocessing and engineering design of implantable sensors. Designed and graded problem sets and exams for 30 undergraduates.
- BIOG 1500 (Investigative Biology Laboratory), Cornell University, Ithaca, NY Spring 2018, Fall 2018: Undergraduate Teaching Assistant for Prof. Mark A. Sarvary Laboratory course with 350+ students with emphasis on processes of scientific investigations and promoting communication, literacy, and collaboration in science.