The introduction of new CASs results in a multiplication of the number of different systems in the airspace. And this is not without consequences. During ACAS Xa integration tests, though the coordination was working perfectly, it was noted that the performances of TCAS were degraded. This highlighted the fact that CASs need not only to be able to coordinate but they also need to be interoperable.
A comparison between ACAS Xu and DAIDALUS has been recently performed by the NASA. Their results show some discrepancies between the two methods and some unexpected behaviors from ACAS Xu and DAIDALUS.
According to the ICAO’s RPAS manual, a full Detect And Avoid (DAA) system must prevent collisions with: conflicting traffic, terrain and obstacles, hazardous meteorological conditions, ground operations and other airborne hazards (such as wake turbulence, birds and volcanic ash). However, most of the existing efforts focus on DAA for conflicting traffic as it represent the highest risk, letting aside the rest of the hazards. Especially in the case of ACAS Xu which design and evaluations focus on conflicting traffic avoidance.
Recently, Trustwave applied for a patent describing how to integrate existing terrain and weather avoidance systems with ACAS Xu. The goal being to inhibit collision avoidance maneuvers which could direct the RPAS into terrain or hazardous weather, and to account for these in the computation of Remain Well Clear (RWC) maneuvers.
The efficiency of such a system remains to be demonstrated, yet it is one step closer to a complete DAA system.
JARUS members shared their experience and needs with respect with Collision Avoidance Systems evaluation so the Chair could refine the scope of its BCAS benchmark project.
Unlike other ACASs (ACAS II, ACAS X), ACAS Xu can provide both vertical and horizontal resolutions. The challenge is: how to choose between vertical and horizontal maneuvers? The choice is done by a module called Nucleus. However, little information on what Nucleus might be was publicly available until last September.
As mentioned in a previous post, the RPAS Chair team has submitted two papers to the 35th Digital Avionics Systems Conference (DASC) 2016, in Sacramento, CA.
For the 35th Digital Avionics Systems Conference (DASC 2016) dedicated this year to Avionics for UAS/UTM, the Chair’s researchers submitted their work on two topics