Robust Adaptive Controls for Shipboard Landing of Multi-Rotor Unmanned Aerial Vehicles

Alex Bryant and Lauren Ingmire in the lab.

A newly funded project in the School of Aerospace and Mechanical Engineering makes use of close collaboration between researchers in different fields to improve a critical technology for national defense. Dr. Keith Walters and Dr. Andrea L’Afflitto (now a faculty member at Virginia Tech) are combining their respective expertise in aerodynamics and controls to address a difficult challenge for unmanned aerial vehicles (UAVs).

It is well known that UAVs are increasingly being used for both commercial and military applications. The United States Department of Defense (DoD) currently employs multi-rotor helicopters (quadcopters) for remote sensing missions, such as surveillance and search and rescue. In the future, they will support troops by performing tactical tasks, such as picking up and dropping off payloads and surveying cluttered environments. Of particular interest are vehicles that operate autonomously, that is without any direct control by human pilots. These vehicles use onboard computers and mathematical control algorithms to perform necessary aerial maneuvers, travel to desired locations, avoid obstacles, and perform whatever tasks are required of their mission. The development of new and improved control algorithms is, therefore, an active area of research with the potential for substantial impact on next-generation UAVs.

This project focuses on the development of improved control algorithms specifically designed for the landing of UAVs on U.S. Navy ships. Shipboard landing is a complex task for UAVs because 1) the deck is highly unsteady in rough seas; 2) adverse sea conditions are often accompanied by adverse weather and high winds; 3) the superstructure of a moving ship induces a wake in the air, which further perturbs the UAVs landing on its deck; 4) near hard surfaces, the ‘ground effect’ alters the thrust produced by the propellers; and 5) UAVs returning from a mission may be damaged. To land on the deck of a ship, a UAV’s control system regulates the thrust forces of each propeller so that the aircraft approaches the ship with some desired relative velocity and orientation, leading to (hopefully) a gentle touch down in the appropriate location.

The primary objective of this research is to design a robust adaptive control system for multi-rotor UAVs that allows precise landing on the deck of moving ships. The work builds on prior research by former AME faculty member Andrea L’Afflitto and will make use of a model reference adaptive control (MRAC) architecture. Such an approach guarantees robustness of the closed-loop feedback system to both uncertainties in system parameters and unknown state-dependent disturbances that affect the control inputs, such as wind gusts or the swinging of an attached cargo payload.

The control algorithm will also be improved by adopting more realistic functional relationships between propeller rotational speed (RPM) and the generated thrust. Currently, it is assumed that thrust is simply proportional to RPM squared under all conditions. While this is often nearly true when a UAV is hovering in calm air, it does not hold during complex aerial maneuvers, under the action of strong wind disturbances, or when the vehicle is close to a solid surface such as the deck of a ship. Keith Walters and his students will perform computational fluid dynamics (CFD) simulations of quadrotor propellers to more accurately determine the relationship between thrust and RPM under these conditions. The simulations will be used to develop an analytical function that will be included in the control algorithm developed by Dr. L’Afflitto.

The scientific advances made by this project will be disseminated in the technical literature and will provide opportunities for graduate students to participate in national or international conferences. The improvement to UAV performance during shipboard landing will be critical to increasing the value of these vehicles to U.S. Navy missions, and the technology can be translated to other branches of the armed forces to improve design and operation of their next-generation UAV systems. Eventually, the research may be adopted by the commercial sector to improve, for example, the use of UAVs for package delivery or remote sensing in adverse weather conditions.

AME Graduate Students Create Evaluation App

Sam Jett, a mechanical engineering graduate, and Zach Schuermann, a mechanical engineering and computer engineering graduate created an app for students to evaluate professors and courses. In the video below, Sam Jett gives a tutorial for The Student-Teacher Evaluation Visualization app (STEV) and explains why they decided to create it.

Click here to visit the STEV web app.

 

 

Development of Zero-Liquid Discharge Freeze System to Remove Dissolved Salt from Contaminated Water

Management of waste water is a challenging issue in many municipal and industrial sectors. The oil and gas industry produces a massive amount of waste water during production. The production of one barrel of oil results in approximately nine barrels of water that is contaminated with salt, heavy metals, and organic compounds. The development of methods for cost-efficient disposal and re-use of produced water without damage to the environment is a critical need for the oil and gas industry. Also, re-use of the water for agricultural purposes will be helpful because the agricultural sector is a primary consumer of increasingly scarce freshwater (accounting for 63% of U.S. surface water withdrawals, according to the U.S. Geological Survey).

Researchers Discuss Equipment with Assistants Castillo Alejandro and Aly Elhefny

In this project sponsored by the US Department of Energy, Drs. Shabgard, Cai and Parthasarathy are working on the development of a novel, zero-liquid discharge freeze system to remove dissolved salt from contaminated water. Freeze-desalination processes are well suited for these situations because pure ice crystals can be produced even in highly concentrated brine. However, current freeze-desalination technologies have some deficiencies that hinder their widespread use. A new method of eutectic freeze desalination will be used with a cooling approach that maximizes efficiency. Thus, the need for energy-intensive evaporation methods is avoided. The density differences between water, ice, and salty brine are used to separate the components. The system will operate under atmospheric pressure and be capable of treating highly concentrated/contaminated water. If successful, the treated water will be suitable for agricultural use, providing an abundant new water source. The goal is to develop a zero-liquid discharge (ZLD) freeze-desalination system capable of treating water with total dissolved solids (TDS) values up to 250,000 mg/l (milligrams per liter). For comparison, the TDS content of seawater is approximately 35,000 mg/l.

The proposed system offers a sustainable solution for the increasing water demand in industrial and oil and gas sectors by recycling the otherwise wasted water, without putting pressure on increasingly scarce freshwaterresources also in demand by local communities for agricultural and municipal purposes. Also, the environmental concerns related to disposing highly contaminated water are avoided by the use of the proposed ZLD desalination system.

Dr. Song’s Research is Promoted in the Press

Dr. Song’s research on developing a smart AC system has received lots of promotion in the media. On August 19, it was promoted in an article by The Journal Record.

The article speaks about Dr. Song and Dr. Tang, an assistant professor from the School of Electrical and Computer Engineering, and their research with making smart thermostats. Dr. Song and Dr. Tang are working on ways to create a cheaper way to cool homes.

Students can read the article for free on the OU Libraries website. Once on the OU Library home page, students can go to databases and e-references, find The Journal Report and then search “OU researchers developing smart AC system that could lower bills by 40%” in the search bar. A full text will be available in the results.

Non-students can click here to visit The Journal Record website where the article is located.

Following the article in the Journal Record, KFOR also promoted Dr. Song’s research. Click here to view the article.

The Sooner Racing Team Competition Results are in!

The Sooner Racing Team had a successful competition at Formula SAE Lincoln, an engineering design competition for undergraduate and graduate students. The team traveled to Lincoln, Nebraska from June 19-22 and exceeded their goals for the competition.

The Sooner Racing Team received 14th in the cost event, 14th in fuel efficiency, 22nd in endurance, 26th in acceleration, 29th in design, and a 10th place award for the quality of their engineering drawings. They finished the competition 33rd overall out of the 80 teams. Additionally, the team got through technical inspections in the first two days with only minor adjustments needed, completed all of the static and dynamic events, and finished the endurance race. Overall, the team is very happy with the results and the way the car came out this year.

Congratulations Sooner Racing Team! Click here to learn more information about the team.

OU Boeing Engineering Days is Featured in The OU Daily

On July 20, 2019, the OU Boeing Engineering Days camp was featured in the OU Daily. Nancy Spears, senior news reporter, wrote about how high school juniors and seniors were able to learn more about the engineering program at OU in the article, “Potential OU students explore engineering programs, sink ‘battleships’ at OU Boeing Engineering Days.”

[from OU Daily Article]

Click here to read the full article.

2019 Capstone Fair Results are in!

The school of Aerospace and Mechanical Engineering held the annual capstone fair on May 2, 2019. Forty one mechanical engineering teams and eight aerospace projects participated in the fair.

Overall 1st Place (tie)

“Sooner Off-Road”: Matt Muhlinghause, Haley Ricks, Devin Prochniak

Overall 1st Place (tie)

“B-52 Spoiler Fixture Redesign”: Morgan Wolfe, Tyler Thibodeaux, Alexandra Arment, Roshan Mathews, Alex Mudd

Overall 2nd Place

“Setup to Evaluate Debris-Scrapper Ring Designs”: Courtney Holloway, Nicholas Son, Alexander Nagy, Abel Rivera, Haydn Kirkpatrick

Overall 3rd Place

“Vehicle Mast: Raising/Lowering Methods”: Michael Evans, Armahn Roozbeh, Austin Petit, Sarah Mailot, Luke Starks

Aerospace Winners Overall:

Overall 1st Place Aerospace

“Boomer Rocket Team Analysis Team”: Abby Roper, Ryan GannonTanner Mann, Nick Cobb, Evelyn Webb, Shaik ZehadBen Shwaiko, Jordan Masterson

Overall 2nd Place Aerospace

“Boomer Rocket Team Manufacturing Team”: Nathan Cook, David Brown, Trevor Trevino, Joshua Hughes, Jalen Johnson, Levi Lunsford

Overall 3rd Place Aerospace

“Design Build Fly Aerodynamics Team”: Vann Wilkerson, Jake Ewing, Alex Bryant, Jen-On Fung

 

Category – Vehicle Design:

Vehicle Design 1stPlace

“Sooner Off-Road”: Matt Muhlinghause, Haley Ricks, Devin Prochniak

 Vehicle Design 2nd Place

“Sooner Racing Team”: Adam Flenniken, Ryan Cowdrey, Justin Porter, Jack Sartin

 

Category – Experimental and Testing:

Experimental and Testing 1st Place

“Setup to Evaluate Debris-Scrapper Ring Design”: Courtney Holloway, Nicholas Son, Alexander Nagy, Abel Rivera, Haydn Kirkpatrick

Experimental and Testing 2nd Place

 “Test Bench for ESP Seal Section Permeability”: Logan Vitello, Travis Wilbanks, Ifeanyi Ijioma, Marshall Thorpe, Logan Roys

Experimental and Testing 3rd Place

“Recording System for Animal Ocular Movement”: Spencer Gallucci, Shangru Wu, Venus Luong, Joshua McCraw

 

Category – Studies:

Studies 1st Place

 “B-52 Spoiler Fixture Design”:  Morgan Wolfe, Tyler Thibodeaux, Alexandra Arment, Roshan Mathews, Alex Mudd

Studies 2nd Place

 “Vehicle Mast: Raising/Lowering Methods”: Michael Evans, Armahn Roozbeh, Austin Petit, Sarah Mailot, Luke Starks

Studies 3rd Place

“Piezoelectric Sensors for HVAC Applications”: Joseph Nostrand, Ryan Perkins, Spencer Hinkle

Studies 4th Place

“FAA OSHA Compliant Climbing Methods for Human Safety”: Wesley Dale, Lauren Tangney, Brent Fenske, Jon Ballard

 

Category – Prototype Design:

Prototype Design 1st Place

“Gaming/Electronics Assist Equipment”: Pranav Mohan, Ashley Medice, Gerald Lance, David Carris

Prototype Design 2nd Place

“Robotic Arm System for Hospital Use”: Luis Donoso, Pum Mang, Tuan Vu, Aaron Vu

The Practical Engineering Award

 “Piezoelectric Sensors for HVAC Applications”: Joseph Nostrand, Ryan Perkins, Spencer Hinkle

 

Category – Presentation:

Presentation 1st Place

“Vehicle Mast: Load Analysis and Failure Modes”: Wesley Dale, Lauren Tangney, Brent Fenske, Jon Ballard

Presentation 2nd Place

“Setup to Conduct Permeation Experiments on Barriers”: Samuel Infanti, Katherine Faux, Karim Aznag, Austin McKee

Presentation 3rd Place

“3D Printing for Shape Memory Polymers”: Colton Ross, Ryan Bodlak, Luke Whitney, Wyatt Maney, Robert Beem

Boomer Rocket Team Receives 3rd Place at Competition

Boomer Rocket Team received 3rd place at the Argonia cup competition. The event took place in Argonia, Kansas from March 30-31, 2019.

The competition objective was to launch a rocket-powered vehicle in excess of 8,000’ AGL. The rocket had to contain a golf ball payload, and the team had to recover the payload safely at a predetermined location on the rocket range.

Congratulations Boomer Rocket Team!

Undergraduate Rocket Research Group has Successful Launch

The University of Oklahoma’s Undergraduate Rocket Research group launched a rocket in Argonia, Kansas on March 10th, 2019. Dr. Thomas Hays and his students are proud of the results.

The rocket had a maximum speed of Mach 1.15 and weighed 105 pounds. The students involved in the launch were Kaley Hassell, Jarod Manning, Alex Speed, and Scott Tesser. Congratulations on your successful launch!

Click here to watch the video of the rocket.

Dr. Zuo Presents Seminar at OU

Dr. Jian Zuo gave a seminar over drug discovery for hearing loss on Thursday, March 14th at OU. Dr. Zuo is a chairman and professor from the Department of Biomedical Sciences at Creighton University School of Medicine.

Abstract: Hearing loss caused by aging, noise, cisplatin toxicity, or other insults affects 360 million people worldwide, but there are no Food and Drug Administration–approved drugs to prevent or treat it. We first performed high-throughput screens for small molecules that prevent cisplatin-induced hearing loss in a cochlear derived cell line. The hit compounds were further validated in cochlear explants, zebrafish lateral-line neuromasts in vivo, and eventually in mouse and rat’s cochleae in vivo. We have so far identified and characterized several potent compounds that exhibit protection against not only cisplatin but also antibiotics and noise-induced hearing loss. We further investigated several targets of top compounds in knockout mouse models. To treat hearing loss, we first developed genetic mouse models in which hair cell regeneration occurred at adult ages. Based on the genetic manipulations, we performed high-throughput screens of small molecules that mimic the genetics models. We further tested these top compounds in adult mice for hair cell regeneration. Combinatory applications of these top compounds could provide therapeutic intervention of hearing loss in clinics.

Biography: Jian Zuo obtained his B.S. in Biomedical Engineering at Huazhong University of Science and Technology in Wuhan, China in 1985. He then immigrated to the US for his Ph.D. in Physiology from UCSF in 1993. After postdoc training in Rockefeller University, he became a faculty at St. Jude Children’s Research Hospital in Memphis since 1998. After 20 years, he recently moved to Creighton University School of Medicine as the Chairman and Professor in the Dept. of Biomedical Sciences in April 2018. He has published >100 research articles and >20 reviews with high impacts. He currently has 2 R01 grants, 2 DoD grants, and one MRC grant. He has trained many successful students and postdocs and has interests in the commercialization of his discoveries.