Da-Vinci tri-copter is built for urban warfare - Defense Update:
New HALO UAV
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Build Something Different, Build a Tri Rotor Drone! - Open Electronics - Open Electronics
Transition flight modeling and control of a novel tilt tri-rotor UAV | Semantic Scholar
Applied Sciences | Free Full-Text | A Nonlinear Robust Sliding Mode Controller with Auxiliary Dynamic System for the Hovering Flight of a Tilt Tri-Rotor UAV
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Yi Technology's Erida Drone Is The World's Fastest Tri-Copter - Lowyat.NET
Aerospace | Free Full-Text | Nonlinear Control of a Single Tail Tilt Servomotor Tri-Rotor Ducted VTOL-UAV