Research at UT Austin
Hover testing on a reduced-scale, coaxial, co- and counter-rotating rotor system
Experimentally investigated performance and vibratory hub loads of a Mach-scale coaxial co- and counter- rotating rotor in hover. Designed and fabricated key components of the coaxial rotor stand including main shafts, swashplates, push rods, a belt-driven power train, and a 1m-radius composite rotor blade.
Operational Modal Analysis
- Also known as output-only modal analysis. It identifies modal parameters (natural frequencies, mode shapes, and damping) only using structural response data, unlike Experimental Modal Analysis (EMA)
- Natural frequencies and mode shapes of a rotor blade in rotating frame were successfully extracted only from structural blade deformation data, measured by Digital Image Correlation.
Results related to this work were presented at the 6th Asian/Australian Rotorcraft Forum 2017 and the 74th American Helicopter Society International annual forum and awarded as a Test & Evaluation Session Best Paper and a Dynamic Session Best Paper, respectively.
- Estimating aerodynamic forces on a helicopter rotor blade based on measured structural blade deformation and rotor thrust.
- The goal is to understand complex helicopter rotor loads mechanism through experimental work, with reduction of time and cost for measurement.
Measurement of transient loads and blade deformation of a coaxial counter rotating rotor
- Measuring transient forces and deformation of a rotor blade due to periodic blade passages in a coaxial, counter-rotating rotor system, with validation of a comprehensive numerical model of the rotor system.
- The main purpose was to investigate the fundamental aerodynamic and structural dynamic phenomena responsible for the transient loading. This collaborative work with the Technical University of Munich has been presented and published at the 44th European Rotorcraft Forum 2018.
Digital Image Correlation
- Calculate full-field deformation of a structure by studying image sequence.
- A sequence of images are taken by stereoscopic high-speed cameras.
- Discretize images into small “sub-set” or “interrogation window” and compare undeformed and deformed images to find a displacement vector at each interrogation window.
Summer internship at NASA JPL
- Aerial vehicles design for exploration of Saturn’s icy moon, Titan. Flight power modeling of the Titan Aerial Daughtercraft mission concepts, where small-scale(e.g.< 10 kg) VTOL aircraft (quadcopter and tailsitter) would conduct multiple sorties from a mothership (lander or balloon) to collect samples from the Titan’s surface.
- Mission feasibility and affordability were investigated based on performance analysis of the VTOL aircraft with environmental parameters of Titan. A research paper based on collaborative work with NASA/JPL has been accepted and submitted to the IEEE Aerospace conference 2019.