Detect and Avoid Alerting Logic for Unmanned Systems (DAIDALUS)(LAR-18464-1)

aeronautics
Detect and Avoid Alerting Logic for Unmanned Systems (DAIDALUS)
(LAR-18464-1)
Overview
DAIDALUS (Detect and AvoID Alerting Logic for Unmanned Systems) is a software library that implements a detect-and-avoid concept for unmanned aircraft systems. At the core of the concept, there is a mathematical definition of the well-clear concept. Two aircraft are considered to be well clear of each other if appropriate distance and time variables determined by the relative aircraft states remain outside a set of predefined threshold values. These distance and time variables are closely related to variables used in the Resolution Advisory (RA) logic of the Traffic Alert and Collision Avoidance System Version II (TCAS II).DAIDALUS includes algorithms for determining the current well-clear status between two aircraft and for predicting a well-clear violation within a lookahead time, assuming non-maneuvering trajectories. DAIDALUS implements algorithms for computing maneuver guidance, assuming a simple kinematic trajectory model for the ownship. Maneuver guidance is computed in the form of range of track, ground speed, vertical speed, and altitude values called bands. These bands represent areas in the airspace the ownship has to avoid in order to maintain well-clear with respect to traffic aircraft. In the case of a loss of well-clear, or when a well-clear violation is unavoidable, the maneuver guidance algorithms provide well-clear recovery bands. Recovery bands represents areas in the airspace that allow the ownship to regain well-clear status in a timely manner according to its performance limits. Recovery bands are designed so that they also protect against a user-specified minimum horizontal and vertical separation. DAIDALUS also implements a pair-wise alerting logic that is based on a list of increasingly conservative alert levels.DAIDALUS is implemented in C++ and Java. The definition of a family of well-clear volumes is also available in Matlab. The software library is modular and highly configurable. The functional requirements of DAIDALUS algorithms have been formally specified in the Prototype Verification System (PVS). The correctness of these algorithms with respect to their functional requirements has been formally verified in PVS. Furthermore, the software implementations have been validated against the formal models using stressing test cases.
Software Details

Category
Aeronautics
Reference Number
LAR-18464-1
Release Type
Open Source
Operating System
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