Autonomous Black Hawk in Flight: Obstacle Field Navigation and Landing‐site Selection on the RASCAL JUH‐60A

Abstract

This paper describes the development and flight test of autonomous obstacle field navigation and safe landing area selection on the U.S. Army Aeroflightdynamics Directorate RASCAL JUH‐60A research helicopter. Using laser detection and ranging (LADAR) as the primary terrain sensor, the autonomous flight system is able to avoid obstacles, including wires, and select safe landing sites. An autonomous integrated landing zone approach profile was developed and validated that integrates cruise flight, low‐level terrain flight, and approach to a safe landing spot determined on the fly. Results are presented for a range of sites and conditions. Approximately 750 km of autonomous flight was performed, 230 km of which was at low altitude in mountainous terrain using the obstacle field navigation system. This is the first time a full‐scale helicopter has been flown fully autonomously a significant distance in low‐level flight over complex terrain, basing its planning solely on sensor data gathered from an onboard sensor. These flights demonstrate tight integration between terrain avoidance, control, and autonomous landing.

Flight test results of helicopter approaches with trajectory guidance based on in-flight acquired LIDAR data

“…In contrast to the works presented in Ref. [5] and [7], this work does not try to achieve full mission planning capabilities or autonomy. Furthermore, the LIDAR installed in the ACT/FHS is body fixed and always facing forward, which limits the benefits of a prior flyover.…”

“…An impressive demonstration of autonomous flight has been presented with the RASCAL 2 research rotorcraft in Ref. [5] using algorithms which have been previously developed for unmanned rotorcraft, see Ref. [6].…”

“…8. In flight, the map changes over time and these images are placed on the flight test engineers map display using a geo-referencing file 5 . This was intended to increase the situational awareness of the crew which parts of the terrain were already known to the systema missing feature in the 2013 trials.…”

Multilayered Mapping and Navigation for Autonomous Micro Aerial Vehicles

“…Whalley et al. () employ five navigation layers to fly 230 km with a helicopter. Obstacles are detected and avoided with an onboard laser scanner.…”

Results of the pilot assistance system “Assisted Low-Level Flight and Landing on Unprepared Landing Sites” obtained with the ACT/FHS research rotorcraft

“…The unmanned aircraft flies automatically through initially unknown terrain and finds a landing zone, all without any human control input. In extension, the manned RASCAL research helicopter flew fully automatically with real-time sensor data processing, reactive trajectory planning, and automatic flight through initially unknown terrain to a final hovering point [18]. The system showed great performance throughout the experiments.…”