Long Range VTOL

**This is a project I am actively working on until May 2021. Updates will be provided periodically**

Overview

Figure 1: Concept Sketch for Outer Mold Line (OML)

For my senior project in mechanical engineering, a team of two students and I are designing a long range vertical take off and landing (VTOL) aircraft. The goal is to create an autonomous aircraft capable of delivering cargo (20-50lbs) long distances (200-500 miles) in a form factor that is ultracompact, reliable, safe, and efficient.

This UAV will take off vertically using powerful electronic ducted fans (EDF). Once it reaches cruising altitude, the EDF's will pivot to provide forward thrust with the lift generated by fixed wings.

The UAV will be powered by a hybrid-electric system in a serial configuration wherein batteries will provide high power to the electric motors for short durations for take off and landing, and a gas powered generator will generate electricity to power the motors and recharge the batteries during cruising flight.

As battery technology improves, fully electric battery powered aircraft will become increasingly popular for short ranges, but hybrid electric systems will remain the most effective solution for long ranges and heavy cargos even as battery energy density passes 500Wh/KG.


This project is currently a work in progress, so this page will be updated upon completion.

My Contributions and Responsibilities

I am working on this project with two other teammates, Noah McGuinness and Nathaniel Spilker. My responsibilities include designing the powertrain, designing the battery pack, designing all electromechanical actuators, coding the autonomous navigation and collision avoidance capabilities, and fabricating the small-scale model.

Powertrain

  • After several iterations, we narrowed down the aircraft sizing and constraints.

  • Given the constraints and intended mission profile, I generated and evaluated potential powertrain configurations.

  • To achieve the large thrusts required in a compact and quiet form factor, electric ducted fans (EDFs) were selected.

  • I contacted several global EDF suppliers, ultimately deciding to work with an Italian supplier called VasyFan.

  • The 250mm EDF's each produce over 50 kg of thrust.

  • Using the motor datasheets and intended mission profile, I created a required energy budget for each stage of the mission.

  • After extensive research, I concluded a serial hybrid-electric configuration was ideal

  • I designed a battery pack using 1850 Li-Ion cells as well as an alternative design using LiPo cells

  • A 4000 W, 2 stroke gasoline generator was selected to generate sufficient electric power to maintain cruising flight for 100-500km with excess power used to recharge the batteries during flight.

Figure 2: 250mm VasyFan Electric Ducted Fans

Figure 3: Pegasus GE70 4000W gas-electric generator

Small Scale prototype

  • A small-scale prototype is being constructed as a full-scale model would far exceed available funding.

  • The prototype features two 70mm EDF's, one 50mm EDFs, three LiPo battery packs, 4 servos, a molded carbon fiber external structure, and various 3D printed mechanisms.

  • The prototype will have a wingspan of roughly 84 cm and max takeoff weight of 4 kg.

  • Currently waiting on remaining parts to arrive to begin testing

Figure 4: 70mm and 50mm EDFs and ESCs for prototype are first parts to arrive