Quadcopter Development

Running Head: ONLY THE BEST

Quad-Copter Development: Making the Best
Engineering & Manufacturing Institute of Technology
Abstract
In November of 2012, Midnight Forty was presented a problem to design and build a multi-copter that could fly both indoors and outdoors, fly through a normal thirty-six inch doorway, hover at any altitude from 4 feet up through 200 feet, and meet many other specifications. After sharing ideas, I got to work on drawing the first model. With my team by my side, we researched and designed the perfect quad copter. After the design was complete, the drawing was sent to both the assembler and the electrician of the team, and they got to work. Fly day arrived, and our quad copter successfully achieved lift. Our pilot maneuvered through the challenges present and landed only inches from where it started.
Quad-Copter Development: Making the Best
Six months ago, the Engineering & Manufacturing Institute of Technology was chosen by The Delta County Sherriff’s Office, along with other companies, to design and build a new remote-controlled airborne “investigate and image-relay.” The design must have been based off a multi-copter design, and meet the given requirements device (Delta County Sheriff’s Office, Dukes Energy, & Strategic Technology Office for Reconnaissance Missions, n.d.). Once this was introduced to the EMIT students, we were teamed up into small groups and got straight to work.
Method
Research Before our team could start designing the multi-copter, we needed to understand all the principles of flight. There were two major things that we would need to know to design a successful multi-copter: Newton’s Laws of Motion, and Bernoulli's Principle.
Bernoulli’s Principle was fairly simple to understand. All you really needed to know is that wind has to travel faster over the top of the wing than the bottom of the wing to stay with the opposite side because the top of the wing is a longer distance than the bottom. Because the top is flowing faster than the bottom, there is a lower pressure system on the top of the wing, and the high pressure below the wing simply pushes the wing up (ALLSTAR Network, 2009).
There are three laws of motion created by Isaac Newton: The Law of Inertia, The Law Defining Force, and The Law of Reciprocity. The Law of Inertia states that an object at rest will stay at rest unless acted on by an unbalanced force, and that an object in motion will stay in motion unless acted on by an unbalanced force. For example, a kickball on the ground will stay in the same place unless you kick it, and it will keep going forward with the same speed and direction until gravity and friction slows it down. In this case, friction would be caused by the ball rolling on the ground, hitting grass or whatever else happens to be there. Gravity also pushes the ball down, changing its direction, where friction will continue to slow the ball down (Sirois, 2006).
The second law of motion explains with force is. Force = Mass times Acceleration. Also, it says that the greater the mass of the object being moved, the more force you will need to move it. This relates to flying because you need to know how much your aircraft weighs in order to decide what kind of engine you will need to successfully produce lift (Sirois, 2006).
The third law, often called The Law of Reciprocity, says that any action has an equal and opposite reaction. For example, a rocket’s action is pushing on the ground, and its reaction is the ground pushing upward on the rocket, producing lift. The same goes for rotors pushing air downward, and its reaction is the air pushing the aircraft upward. With these principles of flight in mind, our team was educated enough to design an efficient multi-copter (Sirois, 2006).
We also thought about easy ways to distinguish the front of the quad-copter from the back. For this, I thought about how ships and aircrafts show their direction: Port and Starboard. From my great understanding of flying from previous airplane classes, I knew that Port is red, and was located to the left when flying away, and Starboard is green, located to the right when flying away. When the aircraft is coming towards you, the colors are switched, showing you the direction the aircraft is going (Rollo, 1998).
Design
The first thing our team would do was decide what kind of multi-copter we would use. We soon decided that the best type would be a quad router and that the style would be in the X shape. We also decided that we would use carbon fiber, and our design would have front and rear supports, as well as 3D printed motor mounts that also functioned as claw landing gear.
In the actual designing of our quad-copter, we took a different approach. We designed our quad-copter from the outside in, making it as small and effective as possible. Designing it this way made our base model very lightweight, which would increase our maneuverability without sacrificing stability. We also designed our quad-copter to have its weight balanced around the center of gravity. Things like placing the battery closer to the center, and placing the camera farther away from the center allows quad-copter to fly more smoothly.
Decisions
Many of our decisions were made in the design stage, because most of our decisions would change what the actual model would look like. Things like the material that we would use, and where to put the electronics would not only change the model on the computer, but also change how the actual frame would look. Most of the time, decisions are based off other decisions. For example, before designing or landing gear and motor mounts, we would have to determine how large to make the holes that would allow the piece to slide onto the end of the carbon fiber rods. The key is to keep asking questions, and those lead to other questions, and eventually we knew exactly what we needed to design an efficient quad-copter.
Modifications
Throughout the assembly, things didn’t work out like we planned them too. Things like the frame being too weak or wires being too short made the assembly longer than we expected it to be. All these problems were solved though, quite easily actually. The point where the supports and the frame met was reinforced with pieces of lexan that would hold the frame and supports together. To fix the short wires, electronics were simply moved to fit the wire lengths.

Results
Fly day arrived, and we brought our finished Quad-copter out to the field. Before we even flew, we knew our quad-copter would be a success. When it was our turn to fly, we successfully completed the challenge given to us, and the strength of carbon fiber showed as we landed roughly. Everything we have prepared for showed as we got our quad-copter off the ground, and completed the challenge successfully. Our quad-copter did not break, either. It is still in one piece waiting for someone to fly it again, and as the TLA is coming to an end and the final quad-copters are being selected, that is exactly what is going to happen.
Discussion
I think this was a very successful TLA for my team. We worked hard and it paid off. The only thing I could think to change would be meeting up more often so we could get work done sooner, but the team-time provided was still enough to get the job done effectively. I had a great team that didn’t mind listening to the team leader, or anyone else in charge. They completed their assigned part every team-time, and they completed it nicely. Everyone got along, and I think the team and I had a better experience than a lot of other people.
References
ALLSTAR Network (Ed.). (2009, November 30). Bernoulli's principle. Retrieved December 5, 2012, from http://www.allstar.fiu.edu/aerojava/pic3-2.htm
Forestblue (Ed.). (2012). Multicopter basics. Retrieved December 5, 2012, from http://multicopter.forestblue.nl/multicopter_basics.html
Rollo, P. M. (Ed.). (1998, March 4). Port and starboard. Retrieved December 5, 2012, from http://www.happychild.org.uk/acc/tpr/mne/1198ptst.htm
Shaw, R. J. (Ed.). (2010, August 26). Vocabulary. Retrieved December 5, 2012, from http://www.grc.nasa.gov/WWW/k-12/UEET/StudentSite/vocabulary.html
Sirois, M. (Ed.). (2006, October 24). Newton's Laws of Motion. Retrieved from http://teachertech.rice.edu/Participants/louviere/Newton/
Tangient LLC. (n.d.). Bernoulli's principle. Retrieved May 21, 2013, from http://physiceducation.wikispaces.com/BERNOULLI'S+CONCEPT

Table 1
This table provided us with the information necessary to balance our quad-copter around the center of gravity using the given specifications.

Table 2
This shows the motor percentage throughout the flight. As the quad-copter lifts off the ground, more power is needed, but the power is soon dropped to hover at a constant altitude. To start moving again, the speed is increased, and after the flight is almost over, the speed is decreased to hovering speed, then cut all together.