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Aerospace Structures Course

Aerospace Structures (AEM 341) is a core aerospace engineering course for the study of methods of analyzing advanced beam and stressed skin structures typical of aerospace vehicles. Dr. O’Neill taught this course in the Spring of 2018.Book: Introduction to Aerospace Structural Analysis, Allen & Haisler, Wiley. ISBN 0-471-88839-7 (Book Review)

Goals: By the end of the course, students should be able to:

  • Understand structural terminology, nomenclature, and aerospace structural elements.
  • Demonstrate basic static and accelerated loads concepts and estimates.
  • Determine principle stresses and principle directions
  • Demonstrate structural analysis of advanced beams and cells in bending and torsion
  • Demonstrate analysis of shear and shear flow
  • Analyze, design and test an aerospace structure as a term project
  • Fluently converse with loads and stress teams in a design setting

Example Lectures:

Course Evaluation: The student course evaluation is at: 18-AEM341-AerospaceStructures. I appreciate the kind words.

  • His notes are extremely clear, and he very effectively communicates the material. He’s far more concerned about us understanding the material than anything else.
  • Helped me regain my hope and enthusiasm for aerospace

XOR Checksum

Recently, I have been working with embedded systems for UAS applications. One of the systems requires commands be validated with an XOR checksum. Rather than doing this by hand, I made a small simple Windows app (download here).Nothing fancy.

Southern Museum of Flight: 2018 Visit

On 4 May 2018, my Aircraft Systems class (and guests) visited the Southern Museum of Flight in Birmingham, AL. Thanks to the museum director Dr. Brian Barsanti for the guided tour. The highlight of the trip was a hands-on visit of a D-21 recon drone under restoration.

A student asked me what I look for at museums. This is quite an excellent question. The truth is that I’ve been around almost all of the aircraft previously. I’m not looking at the aircraft as a famous name but as an interaction…. an aircraft system. Can I figure out the “why” and “how”?

For the 2016 visit, click on https://charles-oneill.com/blog/southern-museum-of-flight-tour-for-aircraft-systems/

More photos are given below

Continue reading

Rewinged SPA

Thank you to Adam Benabbou and Sean Sawaya for designing and constructing a new wing for the SPA aircraft. This wing uses the SD7062 airfoil with a balsa and spruce wing structure covered with Monokote. I am looking forward to a series of interesting missions with this aircraft-wing combination.

SPA

Post Tornado Damage Assessment at Jacksonville State University

On 19 March 2018, a tornado hit Jacksonville State University’s campus. The tornado caused widespread damage across the entire campus and the surrounding neighborhoods. The tornado was a direct hit through the quad, library, and almost all major buildings.

The Remote Sensing Center was asked to provide post tornado damage assessment of the campus buildings. We (Tim Leopard, Chris R. Simpson, and I) flew a series of flights over the campus. We wish JSU the best; we hope these helped.

The full list of videos are below:

JSU Mathews Coliseum: https://youtu.be/7PcHpnTjR6w
JSU West Quad, Dixon, Crow: https://youtu.be/p5i2c85Kqyo
JSU Crow, Patterson, Logan, Sparkman, Williams, Mason, International, Ayers: https://youtu.be/tHb8ldkweis
JSU Quad Area & Closeups: https://youtu.be/I3xqGyD56r8
JSU College Apts: https://youtu.be/9Qrrq-pQqwQ
JSU Library: https://youtu.be/sMytp_HW1AY
JSU McGee, Martin, Library: https://youtu.be/7__QmG9GuPY
JSU McGee, Martin: https://youtu.be/GbicTbK7VjE
JSU McGee: https://youtu.be/RoDeef-8RwA
JSU McGee, Martin: https://youtu.be/1pjEwpOAlbw
JSU McGee, Martin (rapid descent for traffic avoidance): https://youtu.be/AWi1fJBHSus
JSU Softball and tornado track flyby: https://youtu.be/Ewtl6f4mBGo
JSU Honors House 2: https://youtu.be/DlGt1mxbTP0
JSU Honors House: https://youtu.be/1JJAzN8d3aw
JSU Stone Center: https://youtu.be/eBHP4PqSQxE
JSU Stone Center 2: https://youtu.be/gmbhWAn7kTk
JSU Brewer Hall, Merrill Hall: https://youtu.be/_6TULZKz7A4
JSU Merrill East Roof: https://youtu.be/4uBwg-nnIxg
JSU Merrill (Medium altitude circles): https://youtu.be/M5j8y-u-0vc
JSU Library “Wind-Tunnel Gap”: https://youtu.be/csErTiltZ-8
JSU Wallace Hall, ROTC tower, & High Altitude East Campus (E-W lines): https://youtu.be/mcJa-MMOnUo
JSU Rowe Hall: https://youtu.be/shCYSrgGEhM
JSU Rowe Hall, High altitude East Campus (N-S flight lines): https://youtu.be/ecPSHhRJmH8

CATIA on Windows 7 & 10

I own a personal license of CATIA v5. A recent Windows 7 update broke CATIA. Here’s how I fixed it:

  • Open regedit
  • Create “HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\KeyExchangeAlgorithms\Diffie-Hellman”
  • New DWORD Value.
  • DWORD “ClientMinKeyBitLength”
  • Right-click Modify ClientMinKeyBitLength
  • Value “00000200” (Hex value)

[Update Feb 2019]

On Windows 10 machines, the default TLS/Schannel cipher is not enabled. When running “DSCheckLS.exe” the license server status will be “NOT RUNNING”.

To fix this, you will need to enable a specific cipher. In an administrator’s powershell, type: Enable-TlsCipherSuite -Name “TLS_DHE_DSS_WITH_AES_128_CBC_SHA”

This is not at all obvious.

[Personal Setup]

  • Add C:\ProgramData\DassaultSystemes\Licenses\DSLicSrv.txt
  • Occlusion culling
  • Turn off Tablet support: Transformation Pad & Gesture Pad
  • Assembly Design Update Automatic

Surveying Guest Lecture

The Civil Engineering CE 260 “Surveying” instructor for the Fall of 2017 asked me to give a guest lecture and flight demonstration of UAVs for civil engineering applications. The class began with a short lecture (CE260-UAV) and then transitioned to Bryce Lawn for a demonstration flight over the University of Alabama’s old chapel building. My laboratory took the photos and created a 3D reconstruction of the building suitable for civil engineering analysis.

We concluded with an aerial class photo.

Thank you to the CE 260 class and the Civil Engineering department, especially Profs. Graettinger and Stogner.

For reference, the full raw flight video is here. The careful viewer should note that this flight was conducted in accordance with FAA regulations and University of Alabama requirements. Please don’t replicate this flight without first talking to UA compliance, UA Grounds, and the Tuscaloosa ATC tower.

Guest Lecture: Inlet Design

Today, we learn the basics of aircraft inlet design.

This November, I was asked to provide a substitute lecture to a senior level propulsion class (AEM 408). For this lecture, I attempted to provide the basics of inlet design by discussing the relevant physics and constraints.

Inlet fan face total pressure was introduced as a way to quantify the performance of an inlet and to diagnose common issues.

The concept of boundary layer growth with the inlet’s adverse pressure gradient was reinforced from an earlier Aerodynamics I course.

The lecture notes are available here: https://charles-oneill.com/docs/InletTalkAEM408.pdf

Thanks and best wishes to the UA Aero Seniors.

Dr. O’Neill

Post Hurricane Irma Damage Survey

What are the possibilities of investigating storm damage with drones? In 2017, I had the opportunity from a team of Civil Engineers at the University of Alabama to demonstrate a rapid deployment to the gulf coast of Florida after Hurricane Irma.

Hurricane Irma formed off the west coast of Africa on the 27th of August 2017. By the 9th of October, Irma was a category 5 storm off the east coast of Cuba. Irma made landfall at the Florida Keys on the 10th of October at noon as a Category 4. Mainland landfall was on the night of the 10th as a Category 3 to 2.

Logistics

The University of Alabama’s Civil Engineering department rapidly put together a team of approx. 12 members with the specific goal of evaluating the performance of “fortified” homes built to a particular standard. Each of the 4 teams included professors, students, and insurance experts. Teams 1-3 consisted of ground based members surveying the damage, documenting structural and personnel reports, and interviewing inhabitants. Team 4 consisted of UAV operations and a LiDAR scanning crew, with Dr. O’Neill as the professor lead.

The primary lead from the Civil Engineering department was Dr. Andy Graettinger (https://eng.ua.edu/people/andrewg/) with Drs. Kreger, Aaleti, and Hainen.

Our equipment was deployed on Wednesday afternoon to be driven to Fort Myers, FL, where the remaining members rendezvoused on Thursday night. We scanned selected locations in Fort Myers south to Marco Island on Friday and scanned the Tampa area on Saturday. The entire crew returned to UA on Sunday and Monday.

The airspace was relatively simple in the Ft Myers area with a mix of uncontrolled, class D, and class C airports. The Tampa area was more complex with class B, and multiple class D airports. I do appreciate the respective ATC facilities for working with us.

Equipment

My aero team brought two UAS platforms with visible and IR cameras.

  • DJI S900 with an optical camera and IR camera
  • DJI Inspire with an optical camera

We also brought communications and flight mapping software appropriate for operating small UAS/drones in urban environments.

Operations

Operating in a post-hurricane environment presented several challenges. The most pressing was take-off/landing access; this includes obstacle avoidance of the passive type (e.g. trees, poles, wires, waste piles, etc) and active type (e.g. people, vehicles, animals, wind-shear/rotor-vortex, etc).

A secondary challenge in low-lying areas was water inundation. Bonita Springs was completely flooded up to 2+ ft.

The worst damage surveyed was along the Marco island area south of Ft Myers.

The IR camera showed interesting details.

Links