Re:Swiss Post Suspends Drone Delivery Service After Second C...
by walrus01 on Monday August 05, 2019 @11:43PM
(#20621937)
I actually recognize the drone body that Matternet is using there, it's a monocoque molded carbon fiber + fiberglass body from a manufacturer in China, where it's sold as an agricultural spraying drone.
Rapid descent sensors don't necessarily need to be pressure based at all. While in controlled flight there is a limitation (as governed by flight controller and ESCs) for how rapidly a quad, hex or octo can descend. Accelerometer data can be used to trigger a parachute and/or airbag system. A multiply-redundant array of small accelerometers that can detect freefall is very tiny and light weight.
Most higher end flight controllers have double or triple accelerometers onboard.
Furthermore, safety critical systems are all about layers. Yeah redundant motors are good, parachute is nice, but what about passive measures?
Maybe drones should have stub wings which, in addition to lift boost, have deadman switches which cause one to spring 180° on power loss, forcing the hull to autorotate in the event the chute fails.
Ok, the gps dies, the motors fail, chute fails to deploy, and the wing ripped off, you are dropping at full speed. Well now the rapid descent causes a pressure differential (artificial eustacian tube, if you will) which trips some azide charge, inflating an airbag.
It's like they are putting in bare minimum of effort with the quad+parachute.