In a Linkedin post Supernal has given more details of its fiducial-based landing navigation and guidance system.
According to the company’s website:
“Fiducials are custom patterns that can be quickly and reliably detected in camera images using conventional computer vision algorithms. They are similar to QR codes but differ in the aspect that for QR codes to be detected the camera has to be close and near normal to the surface to which the code has been printed. Fiducials, on the other hand, are designed to be detected from much larger off-normal (slant) angles. QR codes are used to encode and convey information, while fiducials are used for navigation. They specifically provide pose (position and orientation) estimates of a flat surface from a camera. Although, a fiducial design with encoded information is theoretically possible, such designs come at the cost of navigation performance.”
Traditional ILS (Instrument Landing System) and MLS (Microwave Landing System) are too heavy for UAM vehicles and GPS navigation performance can be unreliable in dense urban environments, said the company in its social media post. “Hence, we’re exploring new efficient methods for precision landing. We’re planning to place custom design patterns (fiducial markers) on our vertiport and use cameras to localize the aircraft by detecting these patterns.
“This fiducial-based landing navigation and guidance is part of Supernal’s ongoing efforts to develop a fundamental understanding of fog and low visibility conditions for UAM vehicles. Our fog experiments have previously confirmed that fiducial-based precision landing can be used in CAT-I and CAT-II fog conditions for well-illuminated vertiports.
“For night-time or scenarios of extremely low visibility, this guidance will also incorporate infrared beacons to be detected using IR cameras. This relative localization system is expected to have low SWaP (Size Weight and Power), while providing the required navigation performance for UAM vehicles. These explorations are part of our continued efforts to set a new standard for safety and reliability in the skies.”
For more information
https://www.supernal.aero/blog/precision-landing-using-fiducial-markers/
https://www.linkedin.com/company/supernalaero/posts/
(Image: Sample 5 ft. x 5 ft. fiducial painted on a small platform made from I-trac tiles – Supernal)