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FAA issuing new rules to allow drones to fly over people and at night

reuters.com

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Re: FAA issuing new rules to allow drones to fly over people and at night

#201

Post by leetcrew »

pinky1417 wrote: post #184
mynameisvlad wrote: post #177

Earlier quoted context omitted.

This comment thread is about someone adding a parachute to their drone if they lose power, so it doesn’t fall on someone. The propellers would not be spinning, and the object would be gently gliding down.

The drone’s blades would likely still be spinning during a parachute descent... albeit at lower revolutions per minute. I’d imagine drones operate like a helicopter: in the event of an engine failure, the helicopter goes into “autorotation” in which the now unpowered rotor blades move due to the air going through the blades as the helicopter descends, thus braking the fall. However, if drones have locking rotors, the…

this is a reasonable hypothesis, but quadcopters don't work this way. the propellers are usually not large enough to meaningfully slow the descent of the aircraft. also, quads are not stable the way a helicopter with one large rotor is. a drone is likely to tumble when the power is cut.

Re: FAA issuing new rules to allow drones to fly over people and at night

#202

Post by hansvm »

leetcrew wrote: post #199
ohazi wrote: post #193

Earlier quoted context omitted.

I guess that's easier and cheaper than adding a circuit to keep regenerative braking on, but dump the energy into a big resistor...

that would be an unnecessarily complicated way of reimplementing friction brakes.

Most of the hardware is already there for the regenerative brakes, and it allows the driver's muscle memory with respect to braking pressure to still apply in that edge case. I'd be surprised if it were simpler to make the friction brake fallback behave identically to the regenerative system when the battery is full.

Maybe it's not worth the cost/complexity anyway, but the idea has merit somewhere in the design space.

Re: FAA issuing new rules to allow drones to fly over people and at night

#203

Post by oliv__ »

xnx wrote: post #12
ocdtrekkie wrote: post #5

Earlier quoted context omitted.

I have a lot of doubts on the cost/efficiency of this. Keeping things airborne will always cost a lot more energy than rolling things around. Ground-based delivery robots make some sense, air-based ones likely don't.

I had the crazy thought that drones ladden with deliveries could dispatch from the top of a central tall structure (like a skyscraper or antenna), take advantage of the height differential to efficiently glide toward their delivery destination, and then make their return with less weight to carry. Probably very few locales where this could make sense compared to automated sidewalk deliveries like Starship. The speed…

That sounds like such a nuisance, yet so cool! I can picture a beautiful tall geometric metal structure with drones zooming in and out like a mini airport

Re: FAA issuing new rules to allow drones to fly over people and at night

#204

Post by steelbrain »

ohazi wrote: post #193
fiddlerwoaroof wrote: post #152

Earlier quoted context omitted.

Teslas turn off regenerative breaking if you charge too far, but the car tells you that pretty prominently: however, the car handles very differently without Regen brakes.

I guess that's easier and cheaper than adding a circuit to keep regenerative braking on, but dump the energy into a big resistor...

and then you need extra engineering and production costs to cool those resistors :)

Re: FAA issuing new rules to allow drones to fly over people and at night

#206

Post by bigbubba »

ohazi wrote: post #193
fiddlerwoaroof wrote: post #152

Earlier quoted context omitted.

Teslas turn off regenerative breaking if you charge too far, but the car tells you that pretty prominently: however, the car handles very differently without Regen brakes.

I guess that's easier and cheaper than adding a circuit to keep regenerative braking on, but dump the energy into a big resistor...

Aka rheostatic braking. Trains do this, but they have pretty large radiators for it.

Re: FAA issuing new rules to allow drones to fly over people and at night

#207

Post by bigbubba »

hansvm wrote: post #202
leetcrew wrote: post #199

Earlier quoted context omitted.

that would be an unnecessarily complicated way of reimplementing friction brakes.

Most of the hardware is already there for the regenerative brakes, and it allows the driver's muscle memory with respect to braking pressure to still apply in that edge case. I'd be surprised if it were simpler to make the friction brake fallback behave identically to the regenerative system when the battery is full. Maybe it's not worth the cost/complexity anyway, but the idea has merit somewhere in the design space…

If a Tesla would use rheostatic braking, I think it would require more cooling capacity than the cars are currently designed for. If the resistor couldn't be kept cool, then the car would have to revert back to friction brakes anyway. More cooling probably means bigger air intakes, which I think would run contrary to their aesthetic goals.

Re: FAA issuing new rules to allow drones to fly over people and at night

#208

Post by rainbowzootsuit »

macintux wrote: post #163
grumple wrote: post #145

Earlier quoted context omitted.

They aren’t sharp. Doesn’t seem like a realistic concern tbh.

Being hit in the eye with a flying object spinning at high speeds...how much would it matter how sharp the blades are?

Danger: Engage safety squints.

Re: FAA issuing new rules to allow drones to fly over people and at night

#209

Post by kingaillas »

on_and_off wrote: post #128
rkagerer wrote: post #78

Even though I don't fly over people, I retrofitted a parachute onto my DJI drone just in case. It automatically deploys if the drone loses power or control. It doesn't impact flight characteristics or battery life by much. I feel like a basic safety like this would be a prudent and more effective measure for overhead flights than self-transmitting "license plates" (which I agree are at least better than the silly int…

I am always stunned that many (most/all) of these high tech gadgets lack a LOT of safety features. I would pay extra for a drone with such safeguards. just the prospect of less chances of ruining it would be enough. Similarly, eskates often have a regenerative battery charging while braking which is a great idea. but it also cannot handle charging while already full. So if you go down a slope while the board is full,…

>I am always stunned that many (most/all) of these high tech gadgets lack a LOT of safety features.

I’m not... no safety is what the free market will deliver in the absence of regulations or liability or both.

Re: FAA issuing new rules to allow drones to fly over people and at night

#210

Post by URSpider94 »

xvector wrote: post #189
fiddlerwoaroof wrote: post #152

Earlier quoted context omitted.

Teslas turn off regenerative breaking if you charge too far, but the car tells you that pretty prominently: however, the car handles very differently without Regen brakes.

This was the dumbest thing I experienced with my Model 3. I was expecting my regen brakes to work after I pulled out and I had to brake super hard after. Why can’t Tesla just give us an option to keep it consistent? I guess adding video games is more important.

Tesla has been religious about never blending regen and mechanical braking. The accelerator only controls the motors, the brake pedal only controls the brakes. They’ve broken that somewhat now with one-pedal driving mode. The only way they could make regen feel consistent with a cold or full battery would be to blend in friction braking to make up the difference, which is just not something Tesla is into doing.

My BMW i3 did this really well, FWIW.

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