Featured Project

# **TEAM MEMBERS:**

- Yu Tianqi(tianqiy3)

- Li Jinke(jinkeli2)

- Gong Yanzhao(yanzhao8)

- Zhao Qianli(qianliz2)

# **TITLE: VTOL DRONE WITH ONLY TWO PROPELLERS**

# **PROBLEM:**

Nowadays, drones, as an important carrier of new technology and advanced productivity, have become an vital part of the development of new aviation forms. They have been used in many different areas such as military, civilian, commercial and so on. Traditional drones like helicopters have shortcomings in flight speed while fixed-wing aircraft require a runway for takeoff and landing. Vertical takeoff and landing (VTOL) aircraft not only have helicopters' assessibility and flexbility to take off and land in small spaces, thus they can fly to destinations that are not easily accessible by traditional aircraft, such as remote areas or areas with poor infrastructure; the design of VTOL also allows for faster deployment and response times which is especially important in emergency situations where every second counts. Addtionlly, simpler construcrtion of this drone not only reduces over all cost but requires less energy in longer flight time. Overall, VTOL aircraft offer a level of flexibility and efficiency that traditional aircraft cannot match, making them a valuable tool in a variety of industries, including transportation, military, and emergency services.

# **SOLUTION OVERVIEW:**

We plan to design a small VTOL UAV with a wingspan of about one meter to achieve both vertical takeoff and landing and horizontal flight like a fixed-wing aircraft by means of a horizontal tail and rotatable propellers located at the ends of the mean wings. Such two flight modes and the transition between them require a very precise perception and adjustment of the aircraft's attitude. To do this, we need a high frequency motherboard and some gyroscopic sensors to receive and process the aircraft attitude information and make feedback adjustments. This places high demands on the control section, and also on the mechanical side to ensure structural rigidity, reduce unpredictable jitter in the wings and other components, and thus reduce additional attitude adjustments. What's more, we also need to give more thought to the design of the rotatable propeller section. It is important to reduce the inertia of the rotating part while reducing the complexity of the structure and making it more reliable. For our aircraft, the arrangement of internal electronics and storage space has a huge impact on the center of gravity. While designing the aircraft structure with sufficient strength. We also consider the arrangement of the location of each electronic component, the heat dissipation of electronic components, sufficient storage space, certain water resistance, easier maintenance, etc. We believe that with the cooperation of the team members from different disciplines, we can be responsible for our own sub-projects and take full consideration of the design of other sub-projects to complete the overall design.

# **SOLUTION COMPONENTS:**

**VTOL Control Subsystem:** Different from the traditional sliding mode, vertical takeoff and landing makes our drone basically get rid of the dependence on the runway. This subsystem uses the GY-521 breakout of the MPU6050 6 degree of a freedom IMU. It gives adequate measurement precision to stabilize our drone. We use Teensy 4.0 as our microcontroller and use it for robotics, audio projects and Arduino applications (Teensyduino in our drone). After we assemble all the hardware stuff, we need to write the control code in Arduino/C++ language and uploaded them to the Teensy 4.0 board using Arduino IDE. Our drone will use the rotary lift fan to realize the vertical takeoff and landing of the aircraft by relying on the torque force output of the motor according to the feedback information of the IMU.

**Power Subsystem:** The power system will provide sufficient power for the takeoff and subsequent flight of the drone. It mainly includes two motors, two electric regulators, two propellers and batteries. In our VTOL drone, we plan to use Sunnysky brushless motors V2216, KV800, which could provide a maximum force of 1360N each. And according to the working current, we choose 30A electric regulators and 7.4V batteries.

**Mechanical Subsystem:** This system is the main structure of the drone, housing the rest subsystems of the drone. It is also a vital part, providing lift force when the drone is level. It consists of wings, fuselage and tail. In our drone, we plan to use lightweight PLA to 3D print the wings and other small part and laser cut the glass fiber plate to get the fuselage. Carbon fiber rods are also used in the wing parts to support the 3D printed wings.

**Adjustment of the center of gravity Subsystem:** This subsystem consist of a gyroscope and Teensy 4.0 board, which detects the position of the drone's center of gravity in real time and tranmits the information to the board. The board calculates and transmits the porper angle to the servos, so that the drone can fly soomthly in the air.

**Feedback Control Subsystem:** This subsysteem is aimed to ensure the drone mantains a stable flight path and does not deviate from its target orientation. The system works by comparing the current and target orientation and adjusting each propeller's angle according in order toreduce any error. A PID controller is used to determine the necessary adjustments, and it is then sent to the properllers via a servo motor in order to adjust the blades angles. This process is repeated contiually as the drone is flown.

**Flight mode adjustment Subsysytem:** This subsystem contains two servo, Teensy4.0 board, drone remote control and receiver. When the UAV recives a signal to switch from vertical flight mode to horizontal flight mode, it turns the angles od servos so that a horizontal force is generated to move the UAV in the horizontal direction.

# **CRITERION FOR SUCCESS:**

- Flight performance: The drone should be able to take off and land vertically, as well as hover and maneuver smoothly in the air. It should also have a sufficient range and flight time to perform its intended function.

- Payload capacity: The drone should be able to carry the required payload, such as a camera, sensors, or delivery package, while maintaining stability and flight performance.

- Safety: The drone should be designed with safety in mind, including proper wiring, motor placement, and redundancy systems to prevent crashes or malfunctions.

- Reliability: The drone should be built with high-quality components and tested thoroughly to ensure that it operates reliably and consistently over time.

- Cost-effectiveness: The drone should be designed and built in a cost-effective manner, using affordable components and minimizing unnecessary features or complexity.

# **DISTRIBUTION OF WORK**

## ME STUDENT Yanzhao Gong:

- Print and assembly the mechanical parts of the drone.

- Participate in the design of the rotating mechanism of the two propellerso and the follow-up improvement.

## EE STUDENT Qianli Zhao:

- Adjust and control the drone propellers angle when the drone goes from vertical takeoff to horizontal flight.

- Use the gyroscope to detect and adjust the center of gravity of the drone in time.

## ECE STUDENT Li Jinke:

- Participate in the electrical design of the drone. Complete the welding, assembly and debugging of the electronic control hardware equipment of drone

- Implementation and debugging of drone vertical takeoff and landing control algorithm code

## ME STUDENT Tianqi Yu:

- The design of the fuselage part of the structure, the use of glass fiber plate, carbon fiber rods and PLA 3d printing with the design of lightweight, high-strength fuselage.

- Participated in the design of the rotating mechanism of the two propellers at the end of the wing.