Overview

       Unmanned aerial vehicles (UAVs) have grown in popularity as the mechanical and electrical systems that control them have been miniaturized. Duke AMA strives to teach students, from all learning and experience backgrounds, UAV safety, flight skills, and the foundations of aircraft mechanical, electrical, and computational design. By attracting the next generation of students who think on wings and/or propellers and not just on their feet, we hope to teach valuable skills in engineering and design through awe-inspiring applications. 
       Duke AMA provides students the resources to work on aeronautics, electronics, mechanics, autonomy, computer-vision, machine-learning, aerial-photography, photogrammetry, thermal-imaging, and much more. Duke AMA's members are afforded privileges for unsupervised flight which are withheld from most other Duke students. With knowledgeable and dedicated professors and peers, dreams for RC are possible and encouraged.

Leadership History

        My time with Duke AMA began as an enthusiastic member when the club was first chartered. After a short time, I became an authorized spender for the club (Fall 2017) for a project I had proposed. With this activation energy, I fell into the cascade of leadership, becoming the Treasurer (Spring 2018), and eventually, the President (Spring 2019). At the time, the club currently has no other authorized spender, so I retained the treasury position along with the presidency. This is of little import however, as Dr. Martin Brooke, the club's faculty adviser, is the conduit for most of our club's purchases while Yao Yuan (Vice President, 2019), Alex Xu (Secretary, 2019), Shailen Parmar (Flight-Instructor/Safety Officer, 2019), and I handled club organization, funding, and budgeting. 

Bureaucracy

       In the past, clubs at Duke have been able to build UAVs but have been unable to fly them on campus. Some clubs skirted the Duke and government regulations under educational FAA use, but this also forced them to fly at locations far from the heart of campus, even with relatively small craft. 
      The Duke Chapter of AMA now has many designated sites on campus at which we are officially allowed to fly. The primary obstacles to the initiation of this club were overcoming the bureaucratic hurdles of FAA permission, Duke permission, and insurance regulations (through AMA).  Now that the Duke Drone Committee has drawn up documentation with Duke AMA to ensure FAA and Duke compliance, students can be trained, gain certification, and fly, all through Duke AMA. With the permission to exercise aeronautics, we now can focus on our mission to teach, design, and apply the wonderful world of UAVs to the problems of the world. 

Projects
        Duke AMA has allowed students to be more free with their flying. One of the most passionate, if not the most passionate, RC hobbyist and neuroscientist I know is Shailen Parmar. Shailen is Duke AMA's flight instructor and the best freestyle and race pilot I know (don't believe me? watch the videos). Shailen got me more involved with Duke AMA when I first began, and has been amazing me with his flying and intuition ever since. Thank you Shailen for the enthusiasm you have given me and other students for the wild world of unmanned aeronautics. (Video Credits - Audio/Visual, Editing, Flying: Shailen Parmar).
        Duke AMA took over the room of a club that had competed in the XPRIZE Ocean Recovery competition with a 8 ft, 18-rotor, hybrid drone. The room was a mess. More than half of the room was literally unusable until I organized the entire room. This may not sound like much, but many people have tried this in the past and have been met with limited success. Given my combination of abilities to recognize almost any random part and use a label maker, the Duke AMA room has now reached the highest storage density it has ever had and regained much of its functionality. (P.S. I always forget to take "before" pictures but I took during- and after-cleanup pictures) (Spring 2019)
Picture
The Duke AMA club room more than half cleaned.
       I wanted a rather large and capable drone but without all of the problems of transport. For this reason, I designed and built this autonomous, collapsing drone. It uses a Pixhawk flight control system running ArduCopter to perform GPS waypoint guided cinematography and aerial mapping missions. With a 1-axis gimbal that can hold any size camera up to a standard DSLR and extra mounting rails, this drone is capable of more than photography and can lift up 15lbs of payload in addition to itself. Completely collapsed, the drone, battery, and gimbal can be fit inside a 12 x 18 x 6in waterproof case making it carry-on luggage that can fly itself. :P (2020)
        Using standard airfoils, flap-types, and configurations, I built a dihedral, high-wing airplane. The wing surfaces were CNCed out of EPS with a hot-wire. The wings were then sanded, dusted, and coated in packing tape. The packing tape added rigidity, resilience, and a low, consistent surface-roughness to the the wings while being very cheap and very light. The most exotic material used was carbon fiber tubing (in which many of the electronics are mounted). The entire cost of the air-frame materials was less than the cost of the battery and the motor. Version 1 featured a low-mounted fuselage (that proved too bulky and heavy) and dual engines. Version 2 settled for a conventional single-motor setup with connections made inside the carbon fiber tube, and under-wing mounting for the larger electronics. Current electronics and aerodynamic specifications should allow for large amounts of flexibility in the future. (Summer 2019)
       The Bixler3 is Duke AMA's flight-instruction plane. This plane has mild handling characteristics, is easily repaired, and can easily be buddy-boxed first-person-view (FPV) or line-of-sight (LOS). Buddy-boxing is when a student and a master alternate control of the same plane. A momentary switch on the master's radio is depressed to give the student control and released when the plane needs to be righted. This gives members real-world flight training under the supervision of capable pilots, saving models from damage yet dealing with variables a computer could never simulate. I developed a modular FPV platform that works independently of all of the other flight systems and can be easily moved to another plane or removed altogether. (Fall 2017)
       Many of the electronics developed for specific applications of aircraft can be very complex, riddled with bugs, and over-designed. Finding a pilot that is competant enough to take-off and land without fear of crashing is difficult enough. FInding a pilot that can fly an unbalanced plane in anything but optimal conditions is almost impossible, unless you know Shailen Parmar. Putting very expensive, undeveloped electronics that may interfere with flight systems in the air on a plane you are not sure is going to come down in one piece is wasteful and misguided. This is the precise reason I have developed a ground prototyping vehicle. This allows failed iterations of electronics to survive and for more rapid and care-free prototyping and testing.
       Version 1 was mainly a functioning and electronics setup iteration and featured only the bare bones. The frame and skeleton consist of the motor, VESC, steering servo, tie-rods, front-wheel linkages, wheels, and a HTD5M belt and pulley with a 4:1 gear ratio. The VESC was programmed for only forward and electromagnetic braking.
       Version 2 keeps many of the bare bones but changes frames (due to a crash). V2 also adds an FPV module on a 2-axis gimbal that is connected to an accelerometer/gyroscope on the driver's goggles. This allows the gimbal to actuate with head movements, increasing effective field-of-view and the immersive experience. This technology is commonly used in the confined cockpits of fighter aircraft to allow visibility through the fuselage with externally mounted cameras. This directly applies to fixed-wing UAV applications where the direction of travel is static or only changes slowly as it allows a ground pilot to be flying in one direction and looking/filming in a completely independent direction.
       Version 3 puts the finishing touches on a wonderful machine. With a 6:1 gear ratio the design easily handles 45 degree inclines while still maintaining a 35mph top speed on flat ground (limited by wheel imbalance). The chassis was re-designed to feature in-built compliance and flexibility which acts as suspension maintaining 3-wheel contact with any one wheel off the ground by 4 inches. The steering was upgraded to slant the chassis in turns to improve handling. Reverse functionality was programmed in and regenerative braking was added for a >20km mission radius, depending on terrain. Oh, and I designed it to drive upside-down in case of flipping due to wild driving but the video is very disorienting :P . ​(2019 Summer)
     Simulations are at the heart of all of current day design. Through FEA capable software, many different types of simulations and calculations can be analyze to determine many parameters to be approximated from the strength of a drone frame to the aerodynamics of a plane.
     Computers allow for the calculation, assembly, and solution of stiffness and fluid matrices many orders of magnitude beyond what I or most other humans are capable of keeping straight on paper (and also tend to produce far more visually appealing graphics). 
         This is the first FPV video I ever have recorded. As you can see, I need a lot of practice. Through Duke AMA, I finally have the materials and fields necessary to legally test my aerial contraptions. This video was taken with a 500mm quad with 2216, 900KV motors turning 9x4.7 props powered by 40A ESCs fed by a 4S, 450mAh Li-Po. The FPV camera and the VTX are combined in a 25-200mW, 72ch module while HD video is taken by a knockoff E-bay 'go-pro'. Also, the end is long because I find clouds mesmerizing. :P

TO BE DOCUMENTED:

AUVSI SUAS Hexacopter
Rainforest XPRIZE Dodeca-Hexacopter
Professional Pilot Visit