Safety
So the X8 configuration is a good choice but only if configured right because I could not find any information as to how the ESC-s are placed and how many separate controllers are used, what type they are, etc. EHang does say that there are “multiple backups” in place, but what they mean is unclear. The key here is to have separate boards of redundancy where both controllers and ESCs are backed up by fallback systems.
ehang-184-specs
• “Multiple backups” in place
• 4 of the 8 rotors can stop and the vehicle could be able to land safely
• The 184 AAV is embedded with Ehangen fail safe system
• Auto-landing in case of trouble
• On-Star-like command center for fliers who need help
In that case, theoretically even 4 of the 8 rotors can stop and the vehicle could be able to land safely. EHang’s CEO mentioned in an interview that even if 6 motors would fail on 3 of the arms, the AAV (Autonomous Aerial Vehicles) would be able to “spiral to the ground” safely. Well, that sounds kind of scary, doubt that it would not result in anything anyone can survive. The manufacturer says that “the 184 AAV is embedded with Ehangen fail safe system” which suggests that they designed their own solution. Hope they release more information on that.
http://www.dronethusiast.com/ehang-1...er-get-to-fly/