[puckerman]

While there's a whole lot of hype about self-driving cars, I have wondered how much money and effort is being put into "Jetson" cars. By this, I mean the kind of "cars" they have on The Jetsons.

There are certainly benefits to the flying cars. The biggest benefit is that we would no longer need to have any roads to support these cars. It would certainly do away with traffic jams. People could fly over or under them if necessary.

We would still need parking lots. But I suspect that would change as well.

If you don't know what I'm talking about, here's the intro to the show:

[Aurini]

Never.

Flying - whether through aerodynamics wings, helicopter blades, fuel-based jet pack, or magnetic induction - takes a lot of energy. You need to be accelerating upwards at 9.81 m/s2, and just to give you an idea, a car that does 0-100 km/h (~60 mph, = 27.8 m/s) in 10 seconds is accelerating at a rate of 2.8 m/s2.

In other words; take an average sedan and floor it; now go three times faster; that's how much energy it takes to remain stationary above the ground.

Doesn't matter what you're using to hold yourself up; it could be science fiction magnets spinning. It will still require an acceleration of 9.81 m/s2, and the bigger the vehicle is, the more wattage it's going to be putting out.

Maintaining a car at 100 km/h is easy; all you're fighting against is the traction from the road and the push of the air. But the initial acceleration is hard, and all aircraft are constantly accelerating at this rate to maintain their flight.

As a result, the designs of cars vs planes are utterly different. They have entirely different goals in mind. Cars are as different from planes as they are from ships, submarines, and space craft. Each one is doing something unique, and something that does both will do neither well.

Furthermore, aside from the great expense that comes from flying, there's also the great danger; a plane falling out of the sky does a lot more damage than a car travelling down the highway when it crashes. The car only has the energy it expended to get up to highway speed; the plane has been pumping out one-hundred times that to get up to cruising altitude. I don't feel like running the numbers, but it's an easy guesstimate to say that a crashing plane has 100 to 1000 times the amount of kinetic energy as an equivalent-mass out of control car. This is why pilots licenses are so much stricter; these machines can be INCREDIBLY deadly.

For the record, they already have flying cars - but they're shitty cars (no storage space or safety features) they're shitty planes (less range/speed), and even though the novelty might be fun, few people bother with them.

EDIT: Screwed up the math.

[AboveAverageJoe]

Two words. Air Traffic. Also you are adding a whole nother plane of movement. Up-down, not just left-right, forward-back anymore. It would make driving way too dangerous and complicated. Some person above you crashes through the ceiling of my flying car because she leaned into the joystick as she tried to find where she dropped her phone in the cockpit. No thanks. Logistical nightmare. No way to manage all that sky traffic. One reason they are already forcing all drones to have a FAA#.
And if there is one thing NTP taught us all is that-pilots are a special type. Your average driver isn't ready for it and never will be.

[debeguiled]

Drones are nightmare enough.

[weambulance]

Aurini covered what I was going to write.

I hope we'll see a future where most people who don't need to physically do something at their jobs just work from home. That alone would clear up a lot of traffic, and allow people to spread out and live where they want instead of clumping up in urban areas. It would also mean more free time, more disposable income, lower overhead for companies, generally happier people... But I expect corporate America to disappoint me in this.

[JayJuanGee]

(07-03-2016 05:28 PM)debeguiled Wrote:  

Drones are nightmare enough.

The Jetson car was a kind of drone... and so, drones do seem to be a very plausible next step forward, whether they are flying or driving, but certainly I can imagine a world in which fewer people own cars, but instead may own various subscriptions or contracts to cars, and those cars may be held in various warehouses, and maybe at some point some of them may be flying as well, but you will say that you need the car to go run some errands or to buy some furniture, and the car will be dispensed out of the warehouse to get you and take you to various locations... Probably the flying component of the drone, will be further down the road, like 50 years, but would not really be deployed all at once anyhow.. we gotta get to the drone warehousing of cars before we get to the drone flying of cars stage.. but of course, the more wealthy probably are already experimenting with some variations of drone flying apparatuses.. and pilot functions that require fewer and fewer skills from the pilot/passenger.

[dark_g]

DETROIT — The race by automakers and technology firms to develop self-driving cars has been fueled by the belief that computers can operate a vehicle more safely than human drivers.

But that view is now in question after the revelation on Thursday that the driver of a Tesla Model S electric sedan was killed in an accident when the car was in self-driving mode.
Full story

[Aurini]

(07-03-2016 06:29 PM)JayJuanGee Wrote:  

(07-03-2016 05:28 PM)debeguiled Wrote:  

Drones are nightmare enough.

The Jetson car was a kind of drone... and so, drones do seem to be a very plausible next step forward, whether they are flying or driving, but certainly I can imagine a world in which fewer people own cars, but instead may own various subscriptions or contracts to cars, and those cars may be held in various warehouses, and maybe at some point some of them may be flying as well, but you will say that you need the car to go run some errands or to buy some furniture, and the car will be dispensed out of the warehouse to get you and take you to various locations... Probably the flying component of the drone, will be further down the road, like 50 years, but would not really be deployed all at once anyhow.. we gotta get to the drone warehousing of cars before we get to the drone flying of cars stage.. but of course, the more wealthy probably are already experimenting with some variations of drone flying apparatuses.. and pilot functions that require fewer and fewer skills from the pilot/passenger.

Still not feasible, even if we all have mini nuclear power plants in our flying drone cars, or fusion reactors. Even if we invent some sort of zero-point energy, that taps a wormhole straight into the center of the sun - effectively unlimited energy - it still won't work for mass transit for one simple reason:

Heat.

Think about how much heat your car's engine puts out; you've basically got an oven under the hood, and that's merely when it's cruising along the highway. Again, take the energy consumption/output when you're accelerating, and maintain that for half an hour straight; now, multiply that by three (or possibly cube it? Hey, I'm a scifi writer, not an engineer). You wind up with a bunch of coke-ovens flying around in close quarters, that would be raising the ambient temperature by 10-30 degrees celsius. It would be like sitting around in a compressor station all day.

Travel is an engineering problem with a variety of factors; but ultimately, your goal is to provide the smoothest ride possible, even if energy is freely available. Got a regular route that's being travelled? Rail is the best bet. It can be traditional rail, maglev, or some sort of compression-based pneumatic tube system. This is the best mode of transport - period. Now and forever.

Need to get there fast, and price/comfort/safety is no barrier? That's when you fly.

The automobile, meanwhile, provides the best of both worlds; after accelerating, it requires minimal energy to maintain its trajectory, and it has the versatility of going anywhere it wants, without a pre-determined course. Furthermore, the 'infrastructure' at either end of the destination is minimal: nothing but a parking stall. The train needs a station, the airplane needs a massive runway, but all the car needs is a location that's 2.5m/4m square.

Maybe - maybe - we'll see site-specific flying drones, but they won't generally be used for travelling from home to work. Have you ever been in a helicopter? It's cool and all, but I don't want my neighbours calling one of those noisy birds down on their front lawn twice a day.

The car really is the most elegant solution there is; something like the Jetson's vehicle simply denies physics, and you might as well dream about having a flying carpet - or talk about crossing the street by using a 200 lb jetpack.

I strongly recommend this man's blog, he writes about technological limitations, the value of energy (he's noted that nearly all forms of energy work out to the same kW/h rate), and stall speed: www.wimminz.wordpress.com

QUICK EDIT: what dark_g said; people are never going to trust automated cars, let alone helicopters that crash and send a blade spinning out at 200+ mph, slicing through your house and decapitating your wife. The only reasons drones are okay is because they only weigh a few pounds.

SECOND EDIT: A lot of this confusion comes from Star Trek, in my opinion. In the show, you always see the shuttles landing on planets using 'impulse engines' that don't emit massive amounts of exhaust, unlike our launch vehicles which create huge clouds of H2O vapour. The thing to remember is that it doesn't matter *how* the thrust is created - it still takes the same amount of energy to get it done.

The space shuttle launching into orbit requires about the same as one of Star Fleet's shuttles lifting off of the planet; and as for the USS Voyager? When that thing lands on a planet it should be glowing bright red from all the heat generated! Even if their engines are 100 percent efficient, all of that thrust creates an equal and opposite reaction that eventually turns into heat; if there isn't an exhaust port spraying out hot steam, then all that heat stays with the ship until it manages to get rid of it.

So all of that white H20 coming out of the vapour? Concentrate all of it into something the size of a minivan, and think about how comfortable that would be.

[911]

I think we will see those types of personal airplanes as a higher-end transport and hobby tools in maybe 15 to 25 years, not just for the top 1% but maybe all the way down to the top 5-10%. A big house downtown costs millions, you can have a better mansion for a fraction of that price if you live in the exurbs, and a personal flying car which will cost around $100k-150k will end up making that type of real estate arbitrage possible. The economic incentive is there, technology will follow.

Aurini: heat is not a problem for small airplanes, if you're basically flying above stall speed, your engine will be cooled by air flow.

[Leonard D Neubache]

(07-03-2016 05:09 PM)Aurini Wrote:  

Never.
...

Good post. One thing to add.

When a chick forgets to fill up the tank or tries to run her hovercar without having serviced it for two years then you're going to want to get around with a titanium umbrella.

[scorpion]

Larry page (Google co-founder and multi-billionaire) believes so and has been secretly funding two companies trying to build flying cars for years.

http://www.bloomberg.com/news/articles/2...-factories

Personally I'm bearish, but the possibility is definitely intriguing to consider, and the payoff would be big enough that I think it's worth trying to make happen, even if it's unlikely to actually come to fruition.

[porscheguy]

(07-03-2016 07:51 PM)dark_g Wrote:  

DETROIT — The race by automakers and technology firms to develop self-driving cars has been fueled by the belief that computers can operate a vehicle more safely than human drivers.

But that view is now in question after the revelation on Thursday that the driver of a Tesla Model S electric sedan was killed in an accident when the car was in self-driving mode.
Full story

I was going to post this article. Some are saying that the guy had a DVD playing in the front seat when the accident happened. I have a lot of misgivings about self driving cars. The malfunction was that the camera couldn't differentiate between the side of the truck and the sky. Either way, the real malfunction was a driver who was not paying attention. This is something that will be a problem. People will just enter their destination in the GPS, pick up their iPad and watch tv while the car does all of the work. I've even seen people here praise the new technology as it would allow them to be more productive, practice game, etc. All well and good until it fucks up and kills someone. Ultimately, I can't see the automakers going for it because it places even more liability on their shoulders. They'll be getting sued left and right for every parking lot fender bender. Insurance premiums will also go through the roof as they're the first ones who have to pay in the event of such fender benders. They'll have to install video cameras in the car that record every single thing. In the end, I think the reality will not be as pleasant as people are dreaming.

Besides, why would you want it? Long road trips can be painfully boring as it is. Who wants to sit there and observe as the car drives down the road? If anything, it will cause even more complacency.

[Aurini]

(07-03-2016 08:31 PM)911 Wrote:  

Aurini: heat is not a problem for small airplanes, if you're basically flying above stall speed, your engine will be cooled by air flow.

Not the heat within the craft itself (in an atmosphere, heat dispersal is an easy problem to solve), but the heat of 100,000 of these things burning next to each other will be noticeable.

[JayJuanGee]

(07-03-2016 08:31 PM)911 Wrote:  

I think we will see those types of personal airplanes as a higher-end transport and hobby tools in maybe 15 to 25 years, not just for the top 1% but maybe all the way down to the top 5-10%. A big house downtown costs millions, you can have a better mansion for a fraction of that price if you live in the exurbs, and a personal flying car which will cost around $100k-150k will end up making that type of real estate arbitrage possible. The economic incentive is there, technology will follow.

Aurini: heat is not a problem for small airplanes, if you're basically flying above stall speed, your engine will be cooled by air flow.

I'm kind of sharing this thinking - in that the thrust of whether flying cars are going to happen has to do with whether better off folks have desires to have such toys, whether they work well or not and even if such toys do not become economical on a very wide basis. In fact, there is a bit of a status incentive for some folks to want to purchase such devices, and there are a multitude of curiosity incentives that cause inventors and developers to experiment with these kinds of toys.

It is a fairly acceptable practice and even seeming to be a personal incentive that well-to-do folks like to distinguish themselves from the masses by having expensive and possibly impractical toys that regular folks cannot afford, and sure there can be attempts to cause some mass appeal of such toys, but maybe in the end the lack of practicality will cause less than 5% and possibly 10% if lucky of the folks that would end up owning and/or experimenting with such toys.

[Leonard D Neubache]

On a tangeant, perhaps a better model of improved transport could be found in a sort of dual road/rail system where new cars are designed to operate both on roads as per usual and also on a standardised rail system.

Drive into the docking area, the computer takes over and you simply sit back. Rails induce way less friction than tires and the vehicles could be pushed/stopped by an electric shunting system rather than relying on the car owner's engine.

Even if it took longer (it might even be faster), I'd suffer a 20% increase in travel time in order to be able to sit back and read a book without worrying about my self-driving car getting me killed.

[AboveAverageJoe]

I have envisioned a similar idea before where people drive their individual cars to a train depot then all link up like a locomotive train and people disconnect at their stop and they are back under their own power again after being towed en masse much closer to their destination. As a mechanic I am laughing about self-piloted cars. I don't even trust other drivers and I am supposed to trust some death machine produced by Big Auto?

[911]

There is a system already in place where cars link up together electronically and behave like a train on the highways, driving hands-free in a tight single file. A Mech Eng PhD friend of mine helped design one such system in California back in the early 90s. This system increases traffic volume with limited impact on traffic speed, reducing traffic jams, it might take the place of carpool lanes down the road.

I think the flying car also fits in the emerging social paradigm of a shrinking middle class and the richest getting richer, with gated communities, separate air lanes and transport options.

[Suits]

While I see the unlikelihood of this ever coming to pass, I think the ideal solution to unbearable traffic conditions is a lot less sexy than flying cars, self-driving cars or other visions of the future.

I posted the following vehicle in El Mech's Is Your Ride Beta? thread. Although El Mech failed to respond and determine the betaness of my ride, it is really what I ride, although my actually vehicle is a different color, make and model. It looks roughly the same, however.



These vehicles are typically designed to go about 30-40km/hr, but with a slightly bigger/heavier battery, they can go 60-80km/hr.

The problem with big city commuting is that you spend more time stopped in traffic than actually moving. Your car may be capable of going 120km/hr or faster, but you don't get to go that fast and if you calculate all your time waiting for traffic lights and just in traffic jams, your actual average speed is probably more like 5-10km/hr during rush hour.

The solution is to eliminate intersections altogether, but building the infrastructure to do so would come with a massive price-tag and wouldn't even be feasible in a lot of tight city roadways from an engineering standpoint.

Building tiered motorways for an electric powered scooter like the one picture above is an engineering challenge no different from building pedestrian walkways. If you build them as indoor walkways, they'll be usable year round no matter the climate and you won't need to send the plows out every time in snows.

Sure, this won't work for a family of 4 out for a day of fun, but most cars in the city seem to contain only one person with minimum luggage. I see this as a complimentary system to regular roadways, not a replacement.

These can travel fairly safely on properly constructed roads at 40km/hr. Faster than that may be risky, but at those speeds, a crash is unlikely to result in serious injuries if the driver is wearing a helmet and there are no cars or a head-on-collision with a heavy object involved.

[Yatagan]

There's some interesting negative/criminal aspects of flying cars to consider.

- Flying car bombs

- Flying drive by shootings.

- Littering from above.

- Trespassing/intrusion, people would be able to park at/enter a lot of previously inaccessible areas, like being able to park on the roof of a bank or end up on the lawn of the white house.

[monster]

120 years ago no one thought humans would fly.

25 years ago no one thought we'd be able to clone animals and humans.

10 years ago no one thought a high power PC would be able to be compacted into a cellphone.

And now those things charge without even having to plug them in!

So, yes there definitely will be.

[Sooth]

I have no doubt in the future there will be "flying cars".

They will most likely be a hybrid between over sized quad copter drones and small low speed aircraft. The pilot would have almost zero input other than choosing where to land. Air traffic would have to be controlled by computers, similarly computers would effectively fly the vehicle.

Aurini, planes aren't rockets - they don't have to spend anywhere near as much energy as a rocket to achieve the same height. You're vastly over estimating how much energy is required to get airborne. Pure thrust as in rocket propulsion is highly inefficient, but very powerful and also works in the vacuum of space (where wings and propellers don't).

Once a plane is airborne and cruising at altitude, a small aircraft doesn't use a whole lot more fuel than a car when comparing the same trip. A plane can fly direct and quicker. The amount of heat energy generated is about the same as a car for a similarly sized plane.

Here is something I stole:



Before we get flying cars though we will see much more in the way of self driving cars. We're a bit far off putting your feet up and reading the paper yet, but we're going to see more technology around highway cruising, and cars being able to form train like formations to save fuel by reducing air resistance. The next step would then be navigating intersections.

Here is an example of improved intersection flow by allowing cars to calculate the best way to do things. First is normal traffic lights, second is more along the lines of what self driving cars could achieve.





We are already seeing this in the commercial sector in the way of trucking / heavy transport. A bunch of ex Google, Tesla and Apple people started a company and look to have made good progress. - https://www.theguardian.com/technology/2...to-startup

[Mr. D]

I personally don't think we've earned them yet. Give it another 25 years.

[RexImperator]

Self-driving cars are around the corner...which means something else is around the corner: self-driving car bombs.

Allahu Akbar!

[philosophical_recovery]

(07-04-2016 03:29 AM)Sooth Wrote:  

[snip]

Here is an example of improved intersection flow by allowing cars to calculate the best way to do things. First is normal traffic lights, second is more along the lines of what self driving cars could achieve.





We are already seeing this in the commercial sector in the way of trucking / heavy transport. A bunch of ex Google, Tesla and Apple people started a company and look to have made good progress. - https://www.theguardian.com/technology/2...to-startup

Humans are able to do this. But, you don't see this in countries where the traffic laws are rigidly applied, making people docile, inattentive, cellphone users:

[Bluto]

Imagine how bad the DUI wrecks would be with a flying car.