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Electrified wingsuit from BMW reaches 186MPH on first flight

robbreport.com

101–110 of 203 posts

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#101

Earlier quoted context omitted.

Allow me my cynicism (this is HN after all): the rise of electric R/C planes and "foamies" has been a fascinating change in the model-airplane hobby but at the same time it has shown that you can practically put an electric motor + lithium cell on anything and it will "fly". So much so that I feel like the art/science of aerodynamics in modeling has fallen by the wayside. Your run of the mill quadcopter is an ideal e…

I don't understand the lasting appeal of quadcopters in particular. We can build remote-controlled 'normal' helicopters that have fantastic performance and much greater efficiency (no need for 4x the motors and stubby blades). The only downside I understand is that R/C helicopters are very difficult to fly, but that should be straightforward to overcome by putting a basic computer + sensors between the controller and…

I think a large part is that they’re inherently safer with four smaller propellers rather than one big one. So suddenly applications where you’d need a helicopter are accessible to people with less training and skill. Particularly with the robust flying assists and mechanical simplicity.

Then they also turn out to be a readily accessible tinkering hobby very suited to flying around in areas people have nearby. The whole FPV and racing scenes bought in a demographic shift compared with helicopters and fixed wing. Quads are also fantastically agile so quite a different experience to anything else.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#102
post #62

Earlier quoted context omitted.

It’s rather pedestrian in the shadow of this soaring sermon, but I found these Lithium Batteries in the shape of traditional D cells. They put out 1.5v just like regular Ds but the end screws off slightly to reveal a micro usb to charge them! I wish I had these for my stuff when I was a kid. I use them to power my automatic cat feeder. It’s great.

Where?

I’m not going to post the link but they are called Twharf D Cell Batteries 1.5V/5000mAh D Batteries Micro.

I really could not believe it when I charged them for the first time. Here is a pic https://i.imgur.com/2LoyZlR.jpg

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#103
post #82

I'm genuinely wondering when I can buy a personal, commercially available, vehicle that will let me fly (or maybe sail) over the Hudson river on my commute into NYC. What are the stoppers for something like this? Landing? Economics? Regulation? I'd pay more money than a car for something like this.

You can buy a helicopter. They're expensive, loud, and dangerous.

The noise is really bad and one of the reasons I'll vote against any local ordinance that would make heli-transit more available.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#104

> BMW says the electric wingsuit enabled Salzmann to accelerate faster than his mates at a peak speed of 186 mph. (Normal wingsuit operators typically reach horizontal speeds around 62 mph.) Very cool; it appears to be an assist, however, without the power to actually do a takeoff.

15kW should be enough to easily lift an adult human, but the stability implications are a good reason this is an assisted wingsuit and not a jetpack.

Another thing to consider is that saying it has 15kW motors and 5 minutes of thrust does not necessarily mean 5 minutes at 15Kw. That would work out to 1.2kWH weighing what I guess to be about 40 pounds in batteries alone.

I'm really impressed by wingsuits, and strapping a motor onto one just makes it that much cooler.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#105

Lithium-based batteries (and associated tech) are to the 21st century what the internal combustion engine was to the 20th century and what the steam engine was to the 19th century. There’s a ~90% chance you’re using a device powered by a lithium chemistry battery to read this right now (laptop or tablet or phone). The smartphone alone (enabled by lithium based batteries) has transformed the world. Lithium-based batte…

If you are so inclined to answer, I’d live to know why lithium batteries and not some other form of battery? That is, do other elements not have the right properties? Are they too rare? Are they dangerous? You sort of answer a bit in your last paragraph. Why did it take until now to get to lithium batteries? Why way NiCad the thing before? Will lithium continue to dominate, or are there other competitive solutions ju…

Hydrogen cells will always have 10x+ the inefficiency of a lithium battery. They will always be niche for cost reasons.

A NiCd cell has 1.2V per cell, a lithium cell has 3.2-3.7V per cell, so they need to have three times the electron density just to break even. They are about 1.5-2.0x higher IIRC and aren't getting better, while we are still improving lithium slowly.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#106

Lithium-based batteries (and associated tech) are to the 21st century what the internal combustion engine was to the 20th century and what the steam engine was to the 19th century. There’s a ~90% chance you’re using a device powered by a lithium chemistry battery to read this right now (laptop or tablet or phone). The smartphone alone (enabled by lithium based batteries) has transformed the world. Lithium-based batte…

Did you know there were electric cars and they were more popular before ICE cars became more wide spread.

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#109
post #75
post #67

Earlier quoted context omitted.

Having 4 weaker motors is generally safer than one big one if something were to hit it, and you can shorten the blades because the lift is spread across 4x as many blades. Multiple motors is good as well for any motor failures, as quads (if they're well designed) can fly after even multiple motor failures.

With a helicopter, even if you lose the motor (lift) you still have control by adjusting the pitch, angle and ratio of the blades. A quadcopter depends on the motors for any control. While it is possible to regain control after a single motor failure on a quadcopter, it's extremely difficult and not something a human pilot could do, so you'd be relying on software. Also, if you don't detect the failure instantly, the…

Would a proper parachute on a quadcopter be fine in case of motor failure / etc. be okay, then?

Re: Electrified wingsuit from BMW reaches 186MPH on first flight

#110
post #100
post #95

Earlier quoted context omitted.

> A rat is killed, a man is broken, a horse splashes. I had thought that cats could fall from any height safely, but that's not quite true: observational studies suggest [0] they have a 50% or 90% survival rate from terminal-velocity height onto hard surfaces, but not without injury. Still, I'd expect a rat could also "walk away". It's quite a lot smaller than a cat, though it may lack other evolutionary adaptations…

The dual taxonomy of so many animals is interesting. The line between a pigeon and a dove seems to be one of judgment, like with rats and mice. Or the slightly more distant mantis and roach.

Not quite. http://www.ratbehavior.org/RatsMice.htm http://www.ratbehavior.org/RatMouseHybrid.htm
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