Lab

Recommended Tools

In addition to the resources that the course provides, students may find it useful to obtain the tools below:

  • wire cutter
  • wire stripper
  • needle nose pliers
  • screwdrivers
  • hex set (ball ends)
  • electrical tape
  • small scissors
  • a small file

Lab Resources

The Senior Design Lab is located at ZJUI room D225. This lab provides you access to various equipment, some spare parts, computers, and a space to work on your senior design project. In addition, course staff will make themselves available in this lab during their office hours to provide guidance on your project throughout the semester. Your weekly meetings with your TA will also likely be at this location.

It is our intention that this laboratory space provides you and your team with all the tools you would need to develop and test your project (within reason, of course!). If there is something that you require in the lab to complete your project that does not exist in the lab, talk to your TA and we will see how we can solve your issue.

Lab Rules

There are two overarching rules of working in the Senior Design Lab (and, frankly, any shared lab). First, be safe, and second, be courteous. Lab privileges will be revoked if you fail to complete the required laboratory safety training or if you break any of the lab rules. Specific points and examples of what we expect:

Breaking the rules or exhibiting bad laboratory etiquette will lead to a loss of points and/or revocation of laboratory access.

Lab Bench Reservations

We do not expect the lab to become so crowded such that finding a lab bench to work at becomes difficult. However, in the case that this does happen (particularly in semesters with very high enrollment), we will move to a Lab Bench Reservation system. Reserving a bench guarantees that spot for you, however each team may only book one lab bench at a time, and for a maximum of 4 hours per day.

If the lab needs to move to a reservation-based system, you will be notified ahead of time.

A few ground rules:

  1. You may use a lab bench (a) during a time for which you have it reserved or (b) any time during which it is not reserved in the system (on a first-come-first-served basis). However, if you are working at a bench that is unreserved and somebody reserves it using the online system, the group with the reservation gets the lab bench.
  2. There is a limit on the amount of time for which you can reserve benches in ZJUI D225. The limit is currently a total of 4 hours of total bench time in the lab per group per day (e.g., 2 hours at Bench A and 2 hours at Bench B would max out your team's reservations for the day). While this may seem restrictive, keep in mind that the course serves more than 30 groups in a typical semester and the lab has only 14 benches. Also keep in mind that you can work at a bench if it is unreserved.
  3. Some lab benches have specialized equipment at them, such as digital logic analyzers. Try to reserve the lab bench that has the equipment that you need.
  4. Cancel reservations that you will not need as soon as possible to give other groups a chance to reserve the lab bench. You can cancel a reservation up to 1 hour before time and not have it count against your daily allotment.
  5. Conflicts and/or reports of people not following these rules should be sent to your TA with the course faculty in copy.
  6. Above all, be courteous. Especially near the end of the semester, the lab will be more crowded and many teams are stressed. Clean up the lab bench when you are done with it. Start and end your sessions on time. Be patient and friendly to your peers and try to resolve conflicts professionally. If we notice empty lab benches that have been reserved, we will cancel your reservations and limit your ability to reserve lab benches in the future. Similarly, do not reserve more time than you will need. If we notice that you are frequently canceling reservations, we will limit your ability to reserve lab benches in the future. Finally, do not try to exploit the system and reserve a bench for 30 minutes every hour for eight hours. We will notice this and revoke your ability to reserve a bench.

VTOL Drone with Only Two Propellers

Yanzhao Gong, Jinke Li, Tianqi Yu, Qianli Zhao

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.