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A comment on Swiss Post Suspends Drone Delivery Service After Second Crash. Parent comment

Re:Swiss Post Suspends Drone Delivery Service After Second C... by kuzehanka on Tuesday August 06, 2019 @06:22AM (#20623886)
That figure doesn't sound convincing, and the linked paper seems to just make it up without any explanation or justification.

The limiting factor of a quad's ability to fly is the motor and unexpected failure of the battery. Higher end brushless motors have a life expectancy in the tens of thousands of hours. Battery failure is already mitigated in consumer drones by having independent packs each of which provides enough current to continue operation.

Quads do occasionally just fall out of the sky because a defective bearing ceases or a defective cell sags, but it's very rare. Most of the time they crash due to operator error.

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Re:Swiss Post Suspends Drone Delivery Service After Second C... by davinic on Tuesday August 06, 2019 @12:34PM (#20626766)
You've left out the critical component between the battery and the bldc motors: the motor controller. These deal with the most difficult thermal issues and fail frequently.

On a quad there a 4 motor controllers on board, and only one needs to fail, greatly increasing the odds of overall failure.

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Re:Swiss Post Suspends Drone Delivery Service After Second C... by kuzehanka on Wednesday August 07, 2019 @03:40AM (#20632687)
I've never heard of anyone having an ESC fail mid flight. Again, it might happen, but the mean lifespan of a healthy ESC is definitely >100hrs.

None of this is even really relevant. GP quoted a figure from a paper that pulls the figure out of thin air and doesn't justify it in any way. The figure can be disregarded. I'm just pointing out that the figure seems much lower than mtbf of any of the critical components of a quad.

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Re:Swiss Post Suspends Drone Delivery Service After Second C... by neals on Tuesday August 06, 2019 @07:43AM (#20624262)
That's some interesting statistics you claim, would love to see the source on that.
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Re:Swiss Post Suspends Drone Delivery Service After Second C... by dsfyu404ed on Tuesday August 06, 2019 @08:25AM (#20624474)
Considering that mechanical failure is basically a rounding error compared to human error when it comes to causing crashes of every other vehicle and piece of machinery humans operate I'm inclined to believe the same is true for drones.
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Re:Swiss Post Suspends Drone Delivery Service After Second C... by empath75 on Tuesday August 06, 2019 @08:43AM (#20624592)
People have a much lower tolerance for mechanical failure in vehicles that carry people. Anything that crashed at a higher rate from mechanical failure than human error would not be produced for very long.
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