New Electric Drone Has Groundbreaking Flight Time | Hacker News Reader

New Electric Drone Has Groundbreaking Flight Time

spectrum.ieee.org

76 pointskevitivity38 comments

I feel like this is more advertising than actual innovation. They claim that the battery packs form part of the structural frame, but based on the images on the site [0] it looks like they're just loose batteries inserted everywhere. The lithium batteries themselves aren't providing any structural integrity by the appearance of the drone, and I suspect that they end up using more surface area that has to be structural to encase them than if they just had one giant brick in the center with carbon fiber arms.

I'm playing armchair scientist here, but I think the advertising and marketing are better than the actual breakthroughs.

[0]: https://i.imgur.com/usZuqFG.png

That's also terrible from a vehicle agility/stability perspective -- generally you want to centralize mass as much as possible to reduce moment of inertia. Additionally cylindrical cells waste mass on metal casings -- li-poly pouch cells are a better use of mass.

Would you not accept 10x terrible handling for 3x longer flight times?

Depends on the purpose of the mission. Flying for fun or to deliver packages agility is probably more important. Flying for surveillance perhaps it would be better to be in the air longer.

To be fair, what's going to happen to the drone shipping industry is probably the same thing that happened to the naval shipping industry: we will converge somewhere at local minima between super-fast and super-cheap shipping times.

So I could see how fitting the batteries everywhere in the drone might just work. But at the same time I don't see why no one is yet shaping the batteries for the frame itself.

Quad-/Multi-rotors use tilting [1] for steering - including speeding up and slowing, and maintaining / recovering stability. Increased moment of inertia surely increases energy budget necessary for stability and maneuvers, which means lowered energy for flight.

Of course if the weight saving is good enough to offset that, it may still be better off with structural batteries. And the energy budget increase can be calculated pretty well.

[1] achieved by differential thrust, achieved by speeding up / slowing down opposing engines

Tesla thinks otherwise with their new batteries used on model 3 though

They probably aren't optimizaing for mass as much as you would on a flying drone.

The argument that making batteries structural massively contributes to the flight time doesn't seem to be particularly valid anyway. The structural component is likely a tiny proportion of the overall weight. Battery and motors would surely account for the greater part.

After scrolling through their website [0] I can't help but to think of Portal 2's "Official Turrets" trailer [1], except it's batteries instead of bullets.

[0]: https://impossible.aero/ [1]: https://youtu.be/GGPIQ72-2Vg?t=7

>“It never made sense to me that it was possible to have a battery-powered car that could drive more than 300 miles but not have a battery-powered drone that could fly more than about 20 minutes,” he says.

I don't see why...drone flight requires substantial power output to counteract gravity, which increases in proportion to the battery mass. Unlike a rolling vehicle

This stinks of marketing gibberish.

Also very little opportunity for regenerative braking.

While quickly descending use the motors as a generator via autorotation?

I'm only joking, but there might in fact be practical application of the concept.

I don't actually know if it's possible to autorotate a quadcopter. I imagine you would have very little control during the transition. Quadcopters don't fly very high anyway, so there's probably little to gain from it.

ESC electronics usually doesn't support this, but I've wanted to try for many years.

autorotation requires control of blade pitch.

It certainly does in helicopters, which have large, relatively heavy blades you really don’t want to stop turning.

In a quadcopter the blades a small and light, so you could conceivably stop them and let them turn them in reverse as the airflow changes direction (from downwards to up through the blades). I think there would be real problem with control during the transition, and you’d need a lot of height to make it worthwhile.

Unless you use updrafts. Check out dynamic soaring. I have often thought about using updrafts above lava lakes and custom ESCs that can charge batteries to do quadcopter DS.

Having to constantly counteract gravity is just a limitation of this form of aircraft. If it was able to glide, then it would only need to spend energy to maintain height. Some birds can stay in the air for days without landing and they aren't exactly flying batteries.

Why do people buy into this sort of nonsense?? How are VCs and tech writers so incapable of basic conceptual verification?? This company appears to have built nothing except for ideas which don't stand up to the most cursory physical analysis.

Makes me feel bad about the entire ecosystem. All it takes is to have the right network and some charisma to get their money.

Does anyone know about hydrogen-powered drones? Something worth considering? https://danieldonatelli.wixsite.com/hydrogen-generator/hydro...

Yeah, I remember reading about a startup a couple of years ago that was going to have a quadcopter carry a hydrogen fuel cell and a compressed h2 tank. It wasn't complete BS, but the tank was at something insane like 5000 psi if I remember correctly. So it sounded extremely dangerous to me. Anybody remember what this company was called?

Terms like “groundbreaking” and “game changer” get thrown around so much now that they’ve lost all meaning.

why would it be "groundbreaking" if it's in the air :)

When that weight of batteries comes down after running out of power, it will break the ground.

Drone startups often crash so hard they may be said to break the ground on the way down.

If someone would like to check the validity of their claim, here is a great calculation tool for drones: https://www.ecalc.ch/xcoptercalc.php

"Groundbreaking Flight Time" for a quadrotor.

In 2005 AC-Propulsion flew a fixed wing drone for 48 hours and could have gone indefinitely.

https://www.machinedesign.com/news/solar-powered-uav-flies-t...

Not sure how much innovation this is, considering it trades extended flight time for the inability to replace the battery pack. You get to fly longer, but once you're done, you're done until you can plug it in and give it the 90 minutes it needs to recharge. For most applications, field-swappable batteries are a must.

The real breakthroughs will come from new battery chemistry and fuel cells.

“It can reach speeds of more than 68 kilometers per hour, and can fly more than 75 kilometers before recharging.”

So groundbreaking flight time is... one hour?

they say multiple times that drones only regularly do 20-25 mins

While true, groundbreaking should usually mean "order(s) of magnitude" improvement.

It would have been more adequate if, say, the drone could last a day. Which would roughly be a 10x improvement.

Doubling flight time is a huge improvement and could be considered groundbreaking as usually you get incremental improvements of 10-15% a year because of improving battery tech.

Racing drones only ~3 minutes, barely enough to finish a single race (a few laps around the course). And battery is sometimes the limiting factor in races, where pilots have to slow down just so they are able to finish the course and not drop out of the sky before the race ends. Small FPV acrobatic drones fare not much better, 4-5 minutes at the most if you don't fly too aggressively.

The DJI Mavic 2 can stay up for about 30 minutes, according to the manufacturer.

But a racing drone have to be agile. If you put heavy batteries on the extremeties of the drone, it won't be able to roll or rotate very fast. It also takes more energy to fly faster and with more weight.

More specifically, they mean multirotors. Fixed wing aircraft can last much longer. 45 minutes is typical and hours is doable if you have the wingspan and the batteries.

The subtitle of the article is:

> The US-1, from Impossible Aerospace, can fly for 2 hours

If the drones goes at full speed, it loses more energy due to increased fiction with air and between mechanical parts. So, it reaches neither maximum flight time nor maximum flight range. The optimal speed to reach 75km is probably smaller.

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