Showing posts with label aeronautics. Show all posts
Showing posts with label aeronautics. Show all posts

Sunday, November 24, 2024

Robot morphs its wings like a pigeon with real pigeon feathers, the PigeonBot II

Amazing stuff! Fly robot fly! (Song by Silver Convention, 1975) 😊

It is getting fancy with robots?

It appears the earliest PigeonBot research dates back to 2020. 

"Researchers in biomimetics have created a robotic bird model with real pigeon feathers to understand how birds manage to fly without a vertical tailfin.

A plane without a vertical tailfin would be less stable but much more energy efficient and less easy to detect via radar. ..."

From the editor's summary and abstract:
"Editor’s summary
Birds exhibit controlled gliding flight without a vertical tail, unlike the necessary rudders on airplanes that damp Dutch roll oscillations. To accomplish rudderless flight, Chang et al. developed a bioinspired aerial robot with morphing wings and tail named PigeonBot II. The robot consists of a biomimetic skeleton and real pigeon feathers that form wings that can spread and a tail that can spread, elevate, tilt, and deviate side to side like a bird. Initial experiments in a turbulent wind tunnel showed that reflexive tail tilting and deviation combined with wing morphing enabled stable flight by damping Dutch roll. Outdoor flight tests further demonstrated that the autonomous reflexive controller provided stability to the robot during take-off, cruise, and landing. ...
Abstract
Gliding birds lack a vertical tail, yet they fly stably rudderless in turbulence without needing discrete flaps to steer. In contrast, nearly all airplanes need vertical tails to damp Dutch roll oscillations and to control yaw. The few exceptions that lack a vertical tail either leverage differential drag-based yaw actuators or their fixed planforms are carefully tuned for passively stable Dutch roll and proverse yaw. Biologists hypothesize that birds stabilize and control gliding flight without rudders by using their wing and tail reflexes, but no rudderless airplane has a morphing wing or tail that can change shape like a bird. Our rudderless biohybrid robot, PigeonBot II, can damp its Dutch roll instability (caused by lacking a vertical tail) and control flight by morphing its biomimetic wing and tail reflexively like a bird. The bird-inspired adaptive reflexive controller was tuned in a wind tunnel to mitigate turbulent perturbations, which enabled PigeonBot II to fly autonomously in the atmosphere with pigeon-like poses. This work is a mechanistic confirmation of how birds accomplish rudderless flight via reflex functions, and it can inspire rudderless aircraft with reduced radar signature and increased efficacy."

Watch this robot adjust its wings like a pigeon



Fig. 1. PigeonBot II morphs its wing and tail reflexively to fly rudderless autonomously.


Monday, November 13, 2023

Samson Switchblade: First flight for fold-out flying car

Ready for take off! When will we see the first traffic jam in the sky? 😊

"A year after it was pronounced airworthy by the FAA, and 14 years after it was first announced, the Samson Sky Switchblade is officially off the ground. This street-legal three-wheeler converts to a 200-mph (320-km/h) airplane at the touch of a button. ..."

Samson Switchblade: First flight for fold-out flying car (the article comes with three pictures of the vehicle, but none in flight)


Maiden flight


Thursday, June 29, 2023

Weird gimballed-cabin eVTOL "flying car" receives limited FAA approval

Good news! California dreaming! What an oddball! A flying golf cart! 😊

From the story of Alef Aeronautics: "Alef - as in the first letter of a Phoenician, Aramaic, Hebrew, Arabic, Persian, Syrian and other alphabets – signifies the leading position Alef will eventually occupy in the hearts, minds, and garages of the public."

"Alef's Model A is a US$300,000 electric car that's ... kinda street legal, but also capable of a very unique form of flight. The company has announced limited FAA certification. ...
In road mode, there's no way this thing would pass automotive-grade crash tests and the like – nor does Alef want to go through that process. So they've designed it to meet US "low speed vehicle" regulations, which will allow it to potter about on certain streets at speeds up to about 25 mph (40 km/h). Effectively, it'll fall into the same category as a golf cart. ..."

Weird gimballed-cabin eVTOL "flying car" receives limited FAA approval