These would have no trouble charging in that short amount of time. The more difficult issue would be developing a connector that could handle that kind of current, and do it safely while being handled by an ignorant public.
batteries store lots of energy that can be released in an accident.
As far as I can tell, these don't actually qualify as batteries, as there is no chemical reaction. They're capacitors. Of course, capacitors shorting out are not the greatest thing either. Arc flashes are not a fun thing to experience.
Additionally, how well do carbon fibres burn? Like a torch, or like a bomb?
Neither, really. Carbon fiber really doesn't burn. They use the stuff as thermal shielding on the leading edges of the Space Shuttle, and on high end ceramic brakes. Far too often do people conflate "carbon fiber" with "carbon fiber reinforced plastic". Carbon fiber is nothing but a fabric, and like any other fabric, it can't hold a shape. Unless you're just using it for rope or netting, you need some form of sheer matrix to give it stability, and thermoset plastics are simply convenient for that purpose. So obviously a plastic isn't going to hold up well to temperature, but metals and ceramics will, and there is no indication what these panels are to be made out of, other than a nebulous "carbon fiber".
Which is retarded, because of all people, those buying pickup trucks (for actual utility use) should be clamoring over each other for electric versions. If you buy a truck (for reasons other than vanity), you do so to haul things, and if you're hauling things, you want low end torque. Electric motors handily outperform gasoline and diesel engines for low end torque. That's nearly all locomotives have been that way for decades, and modern heavy duty trucks use them rather than turbines.
4) Traditional helis have more blade area, which means more wind disturbance.
5) If you really need the manoeuvrability, and you can handle the increased complexity and chance of failure, variable pitch props can be used for multi-rotor. If anything, they give more manoeuvrability than a standard heli. And you still have the option of high motor counts to get redundancy.
That's the whole point. Longer blades means higher aspect ratio. Larger blade area means lower disc loading. Those in turn mean more thrust, less power consumption, and a reduced tendency for ring stalls under heavy maneuvering. Swashplate or not, you're not going to get that with a multi-rotor.
Large? Yes. Slow? Not hardly. Think about how the two systems operate for a moment. On a direct-drive multi-rotor, rotor RPM directly controls thrust. If you want to increase thrust, you subtract the power needed to counter drag from whatever the motor is outputting, and whatever is left is available to accelerate the rotor. That means you have rapidly diminishing available power as your thrust increases. I question your claim of being able to meaningfully modulate thrust on a multi-rotor at 200Hz. The only way I could see that possible is if your motors were vastly over-speced for your requirements; a trait increasingly difficult to achieve as you scale up.
On a traditional helicopter, the rotor only operates at a single RPM, and you adjust your engine power to maintain that RPM. Your thrust comes from actuation of the swashplate, so your ability to modulate thrust is dependent on the speed of those servos. That's going to be a damn sight better than anything the motors on multi-rotor are capable of. Worst case on being able to modulate proportional thrust in a particular direction is going to be one full blade passing. An RC helicopter of useful size is going to operate at speed of 2000-3000RPM. 3000RPM with a four-blade prop will get you your 200Hz modulation.
So when your upstream can only carry 75% the throughput per channel as downstream, and you only have seven channels of upstream versus several dozen downstream (after video gets the bulk of the channels), that ratio does not reflect the actual behavior of the network?
You've got the Shannon limit, describing the ultimate channel capacity in terms of bandwidth and signal-to-noise ratio. You can increase your bandwidth, but your transmission medium will eventually impose attenuation limits. You can increase your power output, and thus your SNR, but you eventually reach a saturation limit from blooming, ionization, or melting of your medium. There is no theoretical limit on channel capacity, unless you want to go into information theory and figure out the maximum amount of data that can be stored, if your power source is the entire quantity of mass-energy in the known universe, and transmit it over Plank time, but there are functional limits.
Low latency matters considerably depending on the type of protocol you're using. If you have any kind of congestion control, which you should always have unless you're using a fixed bandwidth dedicated link from end to end, high latency will cause some serious problems as soon as you start dropping data.
Anything inside a stadium, they're unnecessary, since you can just do cable-suspended cameras. Anything suspended is going to be much quieter than anything flying.
Actually, what gives finer control is a proper swashplate. All these multi-rotor aircraft pale in comparison to the performance and maneuverability of a traditional helicopter.
The array itself is big and powerful, but it's nothing we haven't been doing for decades, and not the kind of design you would want to use if your whole mission was power generation.
Oh, really? I've seen all kinds of whimsical proposals for space solar power that sort of presumes that the solar panels you can pick up at Harbor Freight (or whatever dealer you can find online or via Amazon) can simply be slapped together with super light weight duct tape and bailing twine and magically be able to transmit that power to the Earth.
When it comes to space, the primary thing you're looking for is ruggedness. You don't want to waste a several hundred million dollar launch because your solar array failed. If possible, you surface mount. If you need more power, you unfold an array with the smallest amount of moving parts you can, which means limited or no sun tracking, which means panels instead of focused solar. If your lifespan needs are limited, you may consider cheaper silicon cells. If you need longer duration, you use Ga-As cells, since they are less susceptible to UV damage.
This design of solar power only works because there is no alternative power source. If you're actually looking to compete with traditional terrestrial sources, you need to cut down on costs. That means cutting down on weight, increasing lifetime, and trading ruggedness for redundancy. You get rid of big panels, and use sun tracked Mylar mirrors. Alignment becomes important, but they're significantly lighter, and unlike panels, micrometeorite damage will only punch tiny holes, rather than short out entire cells. You put heavy filtering on your focused cells to limit degradation. You cool it using... I honestly have no idea. You would probably need a real heat pump to cool those cells with a reasonable sized radiator.
The only thing that could really be done on the ISS related to beamed solar power is actually attempting to beam solar power. Throw a few dozen kilowatt microwave transmitter up there, and actually try to do it. The array itself is big and powerful, but it's nothing we haven't been doing for decades, and not the kind of design you would want to use if your whole mission was power generation.
Earth is a pain in the ass to get off of. The Moon is much much easier, and that's even if you don't bother building a launch rail that would nearly make orbital launches free. The Moon is a stepping stone to the rest of the solar system. Low gravity, easy access to power, easy access to space, easy access to minerals; the surface is pretty nasty, but once you get below the charged, irradiated, pulverized top soil, it's an industrial mecca.
Heat dispersion cartridges? If you've got an effectively infinite energy source, why not just use your projectile as a heatsink? Sure, you'll lose a lot in the transfer, but who cares.
While an otherwise awful movie in every other respect, Ultraviolet actually got that one right. An effectively limitless supply of bullets were stored in a pocket dimension and chain fed through the event horizon into the weapons. Of course, they never resolved the overheating issue, but then if you can create your own pocket dimensions for convenient storage, surely you could figure out a little bit of cooling...
If you're using asynchronous encryption like PGP, then it doesn't matter what the hell they're monitoring. They either have to spend enough computing power to break the encryption, or they have to compromise the private key on your computer.
Unless you're trying to make an interconnect that is media independent, like GBIC or SFP, or running such large distances that you need active repeaters, why would you put any smarts in your cable? That's just retarded. Why can't you simply place the logic inside the phone in the same manner you have dual-mode USB/PS2 mice and keyboards?
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These would have no trouble charging in that short amount of time. The more difficult issue would be developing a connector that could handle that kind of current, and do it safely while being handled by an ignorant public.
They look more like capacitors than batteries. They should be good for millions of cycles.
batteries store lots of energy that can be released in an accident.
As far as I can tell, these don't actually qualify as batteries, as there is no chemical reaction. They're capacitors. Of course, capacitors shorting out are not the greatest thing either. Arc flashes are not a fun thing to experience.
Additionally, how well do carbon fibres burn? Like a torch, or like a bomb?
Neither, really. Carbon fiber really doesn't burn. They use the stuff as thermal shielding on the leading edges of the Space Shuttle, and on high end ceramic brakes. Far too often do people conflate "carbon fiber" with "carbon fiber reinforced plastic". Carbon fiber is nothing but a fabric, and like any other fabric, it can't hold a shape. Unless you're just using it for rope or netting, you need some form of sheer matrix to give it stability, and thermoset plastics are simply convenient for that purpose. So obviously a plastic isn't going to hold up well to temperature, but metals and ceramics will, and there is no indication what these panels are to be made out of, other than a nebulous "carbon fiber".
Which is retarded, because of all people, those buying pickup trucks (for actual utility use) should be clamoring over each other for electric versions. If you buy a truck (for reasons other than vanity), you do so to haul things, and if you're hauling things, you want low end torque. Electric motors handily outperform gasoline and diesel engines for low end torque. That's nearly all locomotives have been that way for decades, and modern heavy duty trucks use them rather than turbines.
4) Traditional helis have more blade area, which means more wind disturbance.
5) If you really need the manoeuvrability, and you can handle the increased complexity and chance of failure, variable pitch props can be used for multi-rotor. If anything, they give more manoeuvrability than a standard heli. And you still have the option of high motor counts to get redundancy.
That's the whole point. Longer blades means higher aspect ratio. Larger blade area means lower disc loading. Those in turn mean more thrust, less power consumption, and a reduced tendency for ring stalls under heavy maneuvering. Swashplate or not, you're not going to get that with a multi-rotor.
Metal 3D printing is a good 20+ years from everyday use. but it starts today.
Technically, it started like 30 years ago, and we've been using manual additive welding for much longer than that, but who's counting...
Large? Yes. Slow? Not hardly. Think about how the two systems operate for a moment. On a direct-drive multi-rotor, rotor RPM directly controls thrust. If you want to increase thrust, you subtract the power needed to counter drag from whatever the motor is outputting, and whatever is left is available to accelerate the rotor. That means you have rapidly diminishing available power as your thrust increases. I question your claim of being able to meaningfully modulate thrust on a multi-rotor at 200Hz. The only way I could see that possible is if your motors were vastly over-speced for your requirements; a trait increasingly difficult to achieve as you scale up.
On a traditional helicopter, the rotor only operates at a single RPM, and you adjust your engine power to maintain that RPM. Your thrust comes from actuation of the swashplate, so your ability to modulate thrust is dependent on the speed of those servos. That's going to be a damn sight better than anything the motors on multi-rotor are capable of. Worst case on being able to modulate proportional thrust in a particular direction is going to be one full blade passing. An RC helicopter of useful size is going to operate at speed of 2000-3000RPM. 3000RPM with a four-blade prop will get you your 200Hz modulation.
Depending on the nature of the reaction, it might be progressing through the medium (like a flame front), so that one could actually work.... :P
So when your upstream can only carry 75% the throughput per channel as downstream, and you only have seven channels of upstream versus several dozen downstream (after video gets the bulk of the channels), that ratio does not reflect the actual behavior of the network?
You've got the Shannon limit, describing the ultimate channel capacity in terms of bandwidth and signal-to-noise ratio. You can increase your bandwidth, but your transmission medium will eventually impose attenuation limits. You can increase your power output, and thus your SNR, but you eventually reach a saturation limit from blooming, ionization, or melting of your medium. There is no theoretical limit on channel capacity, unless you want to go into information theory and figure out the maximum amount of data that can be stored, if your power source is the entire quantity of mass-energy in the known universe, and transmit it over Plank time, but there are functional limits.
Low latency matters considerably depending on the type of protocol you're using. If you have any kind of congestion control, which you should always have unless you're using a fixed bandwidth dedicated link from end to end, high latency will cause some serious problems as soon as you start dropping data.
Look at the speed of that cargo ship!
Anything inside a stadium, they're unnecessary, since you can just do cable-suspended cameras. Anything suspended is going to be much quieter than anything flying.
That sounds like a horrible idea to even attempt fine image stabilization using the rotors themselves.
Not much to go wrong, and not very efficient if you actually want to scale up and carry a decent payload, like a big professional video camera.
Actually, what gives finer control is a proper swashplate. All these multi-rotor aircraft pale in comparison to the performance and maneuverability of a traditional helicopter.
And yet, people who don't understand basic physics seem to think all these quad-/hex-/octo-copters should be scaled up.
The array itself is big and powerful, but it's nothing we haven't been doing for decades, and not the kind of design you would want to use if your whole mission was power generation.
Oh, really? I've seen all kinds of whimsical proposals for space solar power that sort of presumes that the solar panels you can pick up at Harbor Freight (or whatever dealer you can find online or via Amazon) can simply be slapped together with super light weight duct tape and bailing twine and magically be able to transmit that power to the Earth.
When it comes to space, the primary thing you're looking for is ruggedness. You don't want to waste a several hundred million dollar launch because your solar array failed. If possible, you surface mount. If you need more power, you unfold an array with the smallest amount of moving parts you can, which means limited or no sun tracking, which means panels instead of focused solar. If your lifespan needs are limited, you may consider cheaper silicon cells. If you need longer duration, you use Ga-As cells, since they are less susceptible to UV damage.
This design of solar power only works because there is no alternative power source. If you're actually looking to compete with traditional terrestrial sources, you need to cut down on costs. That means cutting down on weight, increasing lifetime, and trading ruggedness for redundancy. You get rid of big panels, and use sun tracked Mylar mirrors. Alignment becomes important, but they're significantly lighter, and unlike panels, micrometeorite damage will only punch tiny holes, rather than short out entire cells. You put heavy filtering on your focused cells to limit degradation. You cool it using... I honestly have no idea. You would probably need a real heat pump to cool those cells with a reasonable sized radiator.
The only thing that could really be done on the ISS related to beamed solar power is actually attempting to beam solar power. Throw a few dozen kilowatt microwave transmitter up there, and actually try to do it. The array itself is big and powerful, but it's nothing we haven't been doing for decades, and not the kind of design you would want to use if your whole mission was power generation.
Earth is a pain in the ass to get off of. The Moon is much much easier, and that's even if you don't bother building a launch rail that would nearly make orbital launches free. The Moon is a stepping stone to the rest of the solar system. Low gravity, easy access to power, easy access to space, easy access to minerals; the surface is pretty nasty, but once you get below the charged, irradiated, pulverized top soil, it's an industrial mecca.
Heat dispersion cartridges? If you've got an effectively infinite energy source, why not just use your projectile as a heatsink? Sure, you'll lose a lot in the transfer, but who cares.
Guns in movies never run out of bullets
While an otherwise awful movie in every other respect, Ultraviolet actually got that one right. An effectively limitless supply of bullets were stored in a pocket dimension and chain fed through the event horizon into the weapons. Of course, they never resolved the overheating issue, but then if you can create your own pocket dimensions for convenient storage, surely you could figure out a little bit of cooling...
If you're using asynchronous encryption like PGP, then it doesn't matter what the hell they're monitoring. They either have to spend enough computing power to break the encryption, or they have to compromise the private key on your computer.
Are you suggesting the federal government for a country as large as Brazil doesn't already have their own email servers?
Unless you're trying to make an interconnect that is media independent, like GBIC or SFP, or running such large distances that you need active repeaters, why would you put any smarts in your cable? That's just retarded. Why can't you simply place the logic inside the phone in the same manner you have dual-mode USB/PS2 mice and keyboards?