Design, flight testing and PID control gain tuning for lift-plus-cruise EVTOL octocopter

As the interest in urban air mobility has increased, naturally the multirotors have become more researched areas. With the increased popularity of "air taxi" concepts, researchers have become more interested in hybrid or lift + cruise multirotor designs. A hybrid octocopter, capable of both hover and forward flight was designed and tested throughout this project. A conventional quadcopter X was designed as a starting point of this project. For the two design iterations, the frame was laser cut and off-the-shelf components were used for the other parts of the quadcopters. The quadcopter was used for getting accustomed to assembling the electronics and the software and conducting manual flight tests. No tangible data was collected from the quadcopters. An octocopter in H shape was designed and was tested only for hover flight. The first design iteration of the frame was laser cut and the second design iteration was 3D printed, while off-the-shelf components were used for all the other components of the vehicle. Ground experiments were done on all the motors used on the hover octocopter using a thrust stand, to validate that all the motors had the same performance. RPM filtering was done using Betaflight software to eliminate any motor noise present. General filter tuning was done using the flight test data to reduce the noise related to the general shape of the vehicle. PID gain tuning was also done in Betaflight software. The gains were tuned by conducting flight tests and analyzing the vehicle performance and PID error. The PID gains were tuned to achieve a stable hover flight of the octocopter. Lastly, a hybrid octocopter capable of both hover and transitional flight was designed with an additional two rectangular wings and motors attached to them for forward flight. The frame was 3D printed, while the wings were laser cut and the rest of the components were off-the-shelf. Ground experiments for the motors were repeated. The filter tuning results from hover octocopter were applied to the hybrid octocopter to eliminate the noise from general shape of the vehicle. Similar PID gain tuning process was done for the hybrid octocopter by conducting flight tests and looking at the hybrid octocopter performance during hover. Once the gains were tuned for stable hover flight, the forward motors were incorporated in the testing. Flight tests were done successfully by reaching the hover altitude of the hybrid octocopter and then only using the two forward motors for translational flight. Lift + cruise flights conducted lasted approximately one minute each.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Aerospace Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2024

Author dc:creator

• Pirosmanishvili, Ani

Contributors dc:contributor

• Merret, Jason M

• Pid
• Control Tuning
• Octocopter
• Uav
• Evtol
• Lift-plus-cruise

Statement dc:rights

• Copyright 2024 Ani Pirosmanishvili

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/127407

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F127407