Daiju Uehara

Daiju Uehara
Honda Aircract Company · Flight Scinence

PhD in Aerospace Engineering

About

11
Publications
4,079
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
79
Citations
Introduction
Experimental study of rotorcraft including modal testing (vibration test), rotor blade deformation measurement, and performance measurement (thrust, pitching moment, and power); Optical measurement techniques such as digital image correlation and particle images velocimetry; Extensive experience in design and fabrication of rotorcraft components from top to bottom with conceptual/detail design by Computer-aided design (CAD); Airload reconstruction from measured rotor blade deformation and modal parameters; Flight power modeling of VTOL aircraft for deep space exploration
Additional affiliations
January 2020 - March 2020
Honda Aircraft Company
Position
  • Engineer
June 2018 - August 2018
NASA Jet Propulsion Laboratory
Position
  • Summer Intern
January 2015 - present
University of Texas at Austin
Position
  • Research Assistant
Description
  • Structural Dynamics
Education
August 2014 - December 2019
University of Texas at Austin
Field of study
  • Aerospace Engineering
August 2014 - July 2017
University of Texas at Austin
Field of study
  • Aerospace Engineering
April 2010 - March 2014
The University of Tokyo
Field of study
  • Aerospace Engineering

Publications

Publications (11)
Article
Full-text available
Link to the full text (http://arc.aiaa.org/doi/abs/10.2514/1.C035469): In a closely spaced, coaxial counter-rotating (CCR) rotor, the passage of upper and lower rotor blades over each other results in transient loads and blade deformation. This paper describes the measurement and numerical modeling of these transient loads and blade deformations in...
Article
"Link to the full text: (https://doi.org/10.1016/j.ymssp.2019.106265)": This study describes the deformation measurement and operational modal analysis (OMA) of an extremely flexible rotor blade in hover. Blade deformation of a 0.45 m-diameter two-bladed rotor was measured at two different root pitch angles and two rotational speeds up to 1500 RPM...
Conference Paper
Flight power and energy requirement models were developed for Titan Aerial Daughtercraft (TAD) mission concepts, in which a small-scale (e.g. ≤ 10 kg) VTOL aircraft would conduct multiple sorties on Titan from a mothership (lander or balloon), recharging batteries from a radioisotope power source (RPS) on the mothership between sorties. The current...
Conference Paper
Full-text available
The present study describes the measurement of transient blade deformation and rotor loads of a single-bladed, rigid, closely-spaced coaxial counter-rotating rotor (CCR) system in hover. Three-dimensional rotor blade deformations were measured using a time-resolved digital image correlation (DIC) technique, simultaneously with the rotor thrust and...
Article
Hover testing was performed on a 2-m-diameter coaxial corotating (stacked) rotor system to investigate the effect of azimuthal spacing, or index angle, on performance. Individual rotor thrust and power measurements were performed as a function of the index angles. It was found that the contributions of individual rotors to the total stacked rotor p...
Conference Paper
This study describes the measurement of transient hub loads and blade deformations due to blade passage in a 1×1-bladed, 2m-diameter rigid coaxial counter-rotating rotor system in hover. The experimental results were analyzed and evaluated in combination with a comprehensive analysis model using CAMRAD II. Lower rotor blade deformations were measur...
Conference Paper
Full-text available
This study describes the deformation measurement and automated operational modal analysis (OMA) of a rotor blade in hover. Blade deformation of a 0.4 m-diameter two-bladed rotor was measured at two different root pitch angles and four rotational speeds up to 1500 RPM by a time-resolved digital image correlation technique (DIC). The DIC technique su...
Conference Paper
Full-text available
This present study describes the deformation measurement and modal identification of an extremely flexible rotor blade in hover. Deformation measurement were performed on two-bladed rotors at four different root pitch angles and rotational speeds by means of a time-resolved digital image correlation technique (DIC). The rotor blade deformations wer...
Conference Paper
Full-text available
Experiments were performed in hover on a 2 m diameter, isolated single rotor system, a coaxial counter-rotating rotor (CCR) system, and coaxial co-rotating (stacked) rotor system to quantitatively extract the swirl recovery of a CCR system. The performance comparison was based on induced power factors obtained from curve fits to momentum theory. Th...
Conference Paper
Full-text available
A Mach-scale, rigid, counter-rotating coaxial rotor system, 80 inches in diameter and operating at a tip speed of 190 m/s was tested in hover in two configurations: two-bladed single rotor and two bladed counter-rotating coaxial rotor. Individual upper and lower rotor steady and vibratory hub loads were collected at four operating conditions for ea...

Network

Cited By

Projects

Projects (3)
Project
An experimental study of a coaxial co- and counter-rotating rotor system from the aerodynamic and structural dynamic perspectives.
Project
The main goal is to develop an analytical model to estimate flight power and energy required by the Titan Aerial Daughtercraft concepts and assess the feasibility and affordability of the whole mission with hybrid fixed/rotary-wing aircraft (with total mass up to 10 kg) for providing greater range with VTOL capability.
Project
Deformation measurement and operational modal analysis (OMA) of an extremely flexible rotor blade in hover using a time-resolved digital image correlation (DIC) technique and the Complexity Pursuit (CP) algorithm