Fully Autonomous Indoor Flight Relying on Only Five Very Low-Cost Range Sensors

Answering what is the bare minimum combination of avionics and vehicle platform design that enables useful autonomous indoor flight without GPS is required to understand the lower cost bounds for indoor UAS technology. The GT Lama indoor Unmanned Aerial System (UAS) capable of autonomously exploring indoor areas in GPS-denied environment discussed here was designed in an attempt to answer this question. The GT Lama weighs around 600 g (1.3 lbs), has a diameter of approximately 70 cm (27.6 inches), and costs less than USD 900. Cost and weight savings are realized through development of an innovative indoor Guidance Navigation and Control algorithm that uses only five small offthe-shelf, low-cost range sensors rather than expensive and sophisticated sensors such as inertial measurement units, scanning laser range sensors, and GPS. The onboard software leverages the inherent stability of the co-axial rotorcraft platform and fuses information from the low-fidelity range sensors to detect and follow walls and other stationary obstacles. The algorithms are designed to encourage maximum exploration of the perimeter of an indoor environment in a reasonable amount of time. The avionics design and the guidance, ∗Graduate Research Assistant, School of Aerospace Engineering, AIAA Student Member †Major, USAF; Recent Graduate, School of Aerospace Engineering, AIAA Member. The views expressed in this paper are those of the authors and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the U.S. Government. ‡Postdoctoral Fellow, School of Aerospace Engineering §Lockheed Martin Professor of Avionics Integration, School of Aerospace Engineering, AIAA Member