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Electrified wingsuit from BMW reaches 186MPH on first flight

robbreport.com

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

#71

Post by HPsquared »

JKCalhoun wrote: post #53
Robotbeat wrote: post #12

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…

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…

It's a matter of scaling laws. You don't see insects or hummingbirds gliding anywhere, small things fly differently.

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

#72

Post by thimkerbell »

bredren wrote: post #62
Robotbeat wrote: post #12

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…

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?

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

#73

Post by sigmaprimus »

joosters wrote: post #60
JKCalhoun wrote: post #53

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 you are probably correct about creating an easier to fly helicopter using a intermediate processor. I also think the argument of longer flight times due to less power draw may be true also.

But cheaper and fewer parts I'm not so sure, part of the reason drones are so popular is the low parts count and part price.

Most low price hobby copters use 3 motors, driving two opposing rotor blades for stability and a tail blade for steering. There are also several gears and bearings to support their functions. Far easier to strap 4 motors with props to a cross and drive them using a solid state SBC integrated with RF,6 axis gyro and 4 power transistors.

Many of these new hobby drones use all the same parts across several different manufacturers so there is an economy of scale to considet too.

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

#74

Post by thimkerbell »

CrazyCatDog wrote: post #14

An electric ducted fan (EDF) is highly inefficient, had they put similar wattage through a gearbox to say a folding prop, efficiency may have doubled (albeit an admittedly more onerous form factor). This is just the beginning of electric assist single passenger flight! Reference: plenty of experience pushing 8KW+ through 2KG RC gliders (F5B) and far slower EDF models.

If someone wanted to learn all this stuff in a "for dummies" class, what course would they look for, among the MOOCs?

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

#75

Post by Diggsey »

palijer wrote: post #67
joosters wrote: post #60

Earlier quoted context omitted.

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…

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 craft will flip over before the software can react because of the inherent instability.

Any solution where you have some kind of passive lift and inherent stability (eg. parachute, wing, etc.) is always going to be much safer.

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

#76

Post by colesdefectum »

heavenlyblue wrote: post #69
reaperducer wrote: post #68

I saw this on the news a couple of days ago. It stated that flight time is about five minutes before the battery runs out. That time in "flight" doesn't seem much different than the time it would take to plummet to your death. The only material difference seems to be the not dying part.

You could use these suits to help pilots who can’t land their plane - they literally only need a few moments of “burn” close to the surface

As a wingsuit pilot I would disagree. Donning the suit is a little more complicated than just strapping on a skydiving rig and you need a fair amount of experience to successfully fly one to begin with. Your parachute system threads through the wingsuit, you still need to tighten leg straps inside the suit before zipping up, tighten a chest strap after zipping up, then zip the arm and leg wings and exit the aircraft with a correct body position and delay to avoid slamming into the tail depending on what type of aircraft it is. It takes a few minutes to put everything on while on the ground, I can't imagine trying to put everything on while a plane is out of control and get it all adjusted properly during an aircraft emergency. Wingsuiters suit up on the ground before boarding so all that's left is to zip up your arm wings and leave the aircraft.

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

#78

Post by tachyonbeam »

simias wrote: post #61
JKCalhoun wrote: post #53

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…

Quadcopters also usually have terribly autonomy. Gliding is a lot more efficient at conserving energy so there's still a lot good engineering to be had in aerodynamics whenever you need to be in the air for more than a handful of minutes at a time. That's why if you look at professional drones you generally only see quadcopters when being able to hover and/or execute very precise motions is required, for the rest win…

It seems to me like there's a good future for electric VTOL. Whether for package delivery or for carrying people, you can take off vertically, and then transition to a horizontal flight regime using wings that's more energy efficient, so you can get more range.

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

#79

Post by Hnrobert42 »

CrazyCatDog wrote: post #19
Hnrobert42 wrote: post #17

Earlier quoted context omitted.

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…

NiCd is actually more capable than NiMh, but suffers from memory issues (capacity decreases significantly if not carefully discharged and recharged; ie you cannot “top them off” without sacrificing capacity. Again, speaking from my lived experience, NiCd pushed to the limit resulted in many gnarly fires in high performance RC use, NiMh was never a contender given low output (again low discharge rates). LiPo is king h…

What about lithium and memory? Do lithium batteries have big memory issues, or is all the stuff rattling around in my head about batteries having memories mostly because I grew up when NiCd and NiMh were all the rage?

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

#80

Post by systemvoltage »

HPsquared wrote: post #71
JKCalhoun wrote: post #53

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…

It's a matter of scaling laws. You don't see insects or hummingbirds gliding anywhere, small things fly differently.

And dangerously. There is no redundancy.
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