Integration of a visibility graph based path planning method in the ACT/FHS architecture

Abstract

This work presents recent progress at the German Aerospace Center (DLR) in landing guidance for helicopter approaches to landing sites without prior reconnaissance. During the project ALLFlight, DLRs research rotorcraft Advanced Control Technology/Flying Helicopter Simulator (ACT/FHS) has been equipped with a sensor suite including a LIDAR sensor, a forward looking RADAR, an infrared camera and a TV camera to provide sensor-based situational awareness. Using the information acquired by the LIDAR, a method for planning an initial flight path from previously unknown landing entry points to the landing point is presented. It is based on a previously developed method using a vehicle point representation, geo-referenced flight surfaces and visibility graphs. A second mode to provide re-planning capabilities in-flight is described. First results of flight tests conducted in 2013 are presented and discussed. Using the data recorded during these approaches, an improved re-planning strategy for the final approach based on so called visibility hulls is presented. This work continues recent research at DLR’s Institute of Flight Systems helicopter department for flight under degraded visual environment (DVE) for a full-scale helicopter.