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by TillE 1065 days ago
Much like Theranos, basic immutable laws of nature make the whole idea absurd. Namely, that it requires a ton of energy to keep an object aloft.

It's just wildly inefficient, and will never see serious usage outside of tiny niches. Not until we get science fiction antigravity or tiny fusion reactors or something.

5 comments

Doesn't it also require a ton of energy to move a five ton truck to my driveway in order to deliver a 100g charging cable?

I'm not sure the laws of physics are on the side of the status quo here.

Hovering like a drone has to overcome gravity, which is hard/expensive. A truck only has to overcome rolling friction, which is easy/cheap.
I would bet that even the worst Amazon truck gets more pounds of product per Joule expended than the best drone for any reasonably real world distance/load.
The difference is both direct ground contact and fuel capacity.

Even if a drone could carry the energy equivalent of a 20 gallon fuel tank with it, it would waste the majority of that energy both keeping itself and its energy aloft.

Tires and other ground plane vehicles, mitigate the majority of that waste in exchange for increased navigational difficulty (regarding obstacles like buildings and trees but also moving objects like vehicles in its path).

The self-driving robots made some sense but only for very local (couple of block radius) delivery.

And fixed-wing aircraft are substantially more efficient than rotorcraft.
Anything that does not have to be constantly and continuously pumped with more energy in order to not immediately crash is going to be more efficient than the alternative.

A paraglider drone with a tiny parachute would be more efficient than any 3/4/6/8 motor drone copter

As usual, the difference is energy density between hydrocarbon fuels and Li-ion batteries. Power the drone with gas and it becomes a different story. But then you just re-created the helicopter and all the problems which explain why no one is doing helicopter package deliveries.
you probably paid at least $5 for that cable, but the cost of materials in the cable was likely less than a dollar

the rest of the money went into the gas tank of the truck

you and everyone else who ordered a cable that day on that route chipped in to fill the truck up

winning response. Thank you for the clarity and simplicity.
Amazon's delivery always felt odd to me because of this exact situation. Long term how sustainable can it be to work on such an extreme scale like that? The margins they must be hiding on via products must be good.
Ironically one of the areas it _is_ being used successfully is in delivery of blood to some areas in Rwanda, but they're using fixed-wing drones and are even doing slingshot launches. [1]

The economics are totally different, though. The "product" is very high value and has a short shelf life, so being able to deliver it quickly is a big benefit.

On top of that, using a fixed-wing delivery vehicle and launching it with a human-powered slingshot makes it actually reasonably energy-efficient.

[1]https://youtu.be/bnoUBfLxZz0

From the same channel https://youtu.be/J-M98KLgaUU

See also https://youtu.be/DOWDNBu9DkU From 3 months ago

Wait why does it require antigravity to deliver some groceries on a drone?
Kiwibots were little wheeled robots that rolled along the sidewalk.
While this may be correct when all possible types of deliveries (weight/distance/geography) are taken into account there are definitely cases where drone delivery is going to be substantially cheaper than similar delivery by vehicle.

Maybe it's my proximity to large bodies of water, but there are many island communities where I live that have limited (or no) road access requiring either a very out-of-the-way route to reach a destination or -- worse -- a ferry. A trip out to some communities could be the difference between a mile travel by air vs 10 miles travel by vehicle.

That's an extreme outlier, obviously, but if you dial that back a bit and use, say, "a trip from my home to my girlfriend's" which involves working around two rivers that roads only cross at certain points, the difference is 5 miles "as the crow flies" vs almost 14 miles of windy roads.

When all of the other problems are worked out, a drone delivery service could augment regular delivery to reduce costs/improve delivery time for products.

I think products that greatly benefit from improved delivery time, though, is the place where drone delivery can be successful. It's currently being used in some countries for blood/medical deliveries and that was the first thing that came to mind when I thought of places where drone delivery would be able to be compete/displace existing providers.

I had a friend who flew a helicopter for a company that moved people/organs/other emergency-releated activities for hospitals. Organ transplants, as I understand them, are extremely time-sensitive. One day he was called on to deliver a liver from a hospital nearby to a hospital mid-state for a waiting patient. Weather, wind, clouds and other variables were excellent; he was on-call and a ways out but made it. Shortly after take-off the helicopter suffered a failure (memory escapes me), it crashed resulting in the death of my friend, (I think) a passenger and ultimately the patient waiting for the organ.

This was 20-ish years ago and in the time since then it was discovered that part of the pre-flight check was skipped and IIRC[0] the crash was determined to be related to condensation in the fuel tank or something along those lines -- basically, he was on-call with a tight delivery schedule and cut a corner to account for the time it took him to get to the hospital for the delivery.

Drone delivery would improve several things in this model. The most obvious one being "no dead pilot or passenger" when something goes awry. If we're "flying things around" especially using small aircraft and GA pilots, there's going to be crashes -- drones or people involved -- it's a guarantee. Using drones would enable deliveries to take place without delays involved in "waking up a pilot on-call/waiting for their arrival" -- allowing hospital staff to prepare the delivery vehicle, make a call, and hand off to a remote drone pilot to get it to its destination. Assuming software/user interfaces can make piloting a drone remotely as safe as flying a helicopter "in person", the benefits would be enough to offset the higher delivery costs.

[0] I tried to find a reference online to refresh my memory but was unable so forgive my memory if I've got some details wrong here.