Laser Propulsion - Scientific Discussion (Engine is real!) +New poll!

[Exorcet]

I know, GM did, but I wonder what exactly the engineers were thinking, although the thread about "exotic propulsion systems" has now been answered XD! Here's what is powered by lasers (mostly the sun, but also but lasers too.)
http://en.wikipedia.org/wiki/Solar_sail

"In the 1970s, Robert Forward proposed two beam-powered propulsion schemes using either lasers or masers to push giant sails to a significant fraction of the speed of light."
...
"A small team had initially proposed a beryllium inflated sail that would go down to 0.05 AU from the Sun in order to get an acceleration peaking at 36.4 m/s2"
...
(36.4 m/s^2 is 3.7 Gs)... but you have to have a gigantic sail and you need a lot of radiation for the sail to catch...
...
I don't think its practical to use it as a cars propulsion.
...
Japan's JAXA successfully tested IKAROS in 2010. The goal was to deploy and control the sail and for the first time determining the minute orbit perturbations caused by light pressure. Orbit determination was done by the nearby AKATSUKI probe from which IKAROS detached after both had been brought into a transfer orbit to Venus. The total effect over the six month' flight was 100 m/s(0.000006 Gs)

Solar sails are a different concept. The 2X laser propulsion is basically a jet engine with laser instead of jet fuel.

I didn't say PD did design the car. But the people who did were presumably the ones who made up things to go with their complete fantasy design that is being put into the serious racing game.

I think the concept is a good fit for a serious simulator. What might not be is that it seems like the 2X is being presented as something that's fully functional and past the concept stages. It would make an interesting proof of concept vehicle, but that would generate less hype/attention, so that wasn't going to happen.

Ask yourself this: Why does the 2X only go 250 MPH? Why does it accelerate to 60 in 1.5 seconds? Why does it make 900 horsepower? Any one of those numbers could be literally everything they wanted them to be. I'm doubting there were any aerospace engineers on the design team for the internal GM design side project.

They could very well be pulled from nothing, although there is quite a wide spectrum between fantasy and truly accurate numbers. The power, speed, and acceleration could just as easily be calculation as they could be imaginary. The first step in vehicle design would be to use the most basic math to see if your idea has a chance. If GM did math with this projected, it might have stopped there or maybe 1-2 steps later, leaving you with hypothetically achievable results, but huge amounts of uncertainty.

it's a bit incongruous to suddenly put in a bunch of cars powered by what might as well be called MAGIC! that make whatever equivalent horsepower and go however fast PD wants to say they do because who is going to prove otherwise?

At first glance, I don't really find the propulsion system to be the "sci-fi-est" element of this car. The question of numbers that you bring up is certainly legitimate. I'm wondering what the benefit is over a gas/electric engine. For light powered aircraft it's the lack of on board fuel (weight), but this car needs to carry batteries to power the laser.

The shockwave thing for downforce is very plausible on paper. The opposite has been done for lift on aircraft (XB-70 Valkyrie) but I feel less certain about this idea without more info.

 

[sk8er913]

The 2X laser propulsion is basically a jet engine with laser instead of jet fuel.

http://upload.wikimedia.org/wikipedia/commons/4/4c/Jet_engine.svg

This diagram makes laser engines seem more practical, but I don't know much about jet engines. Rocket Engines are so much simpler.

 

[Exorcet]

Well the exposed portion of the engine is very much like a rocket, I went with the term jet because I assume air is being funneled to the nozzle from somewhere.

 

[sk8er913]

Well the exposed portion of the engine is very much like a rocket, I went with the term jet because I assume air is being funneled to the nozzle from somewhere.

I posted a video of how jet engines work, its perfect for a laser I will update OP

I believe the laser is more less the fuel for the 2X. The batteries supply the laser with its power and the "air-powered" generator helps the laser for its thrust. Something like a jet/rocket engine in someways.

I'm nothing close to a engineer of any sorts, but this is just my theory on what GM has come up with.

You were right! check out the updated OP!

 

[vr6cas]

I'm more interested in how this Laser system will differentiate the machine itself from the many other machines in the game instead of how wacky it is or is not, or how this has anything to do with how "Serious" GT is supposed to be.

I'm more interested in the driver on how he is positioned laying down flying wing suit for a car idea thingy.

 

[sk8er913]

http://www.lightcrafttechnologies.com/technology.html

This is probably what they based it on more specifically

 

[Imari]

http://www.lightcrafttechnologies.com/technology.html

This is probably what they based it on more specifically

That's pretty nifty. Megawatt lasers to launch a 1kg payload, but it's certainly an awesome concept.

I wonder how well it scales down though. There's a limit to how well the laser will focus based on the stability of the whole rig and the accuracy with which they can manufacture the focusing optics. While scaling it up probably just results in bigger and bigger shockwaves, at some point when scaling down it will simply stop reaching the temperatures required to generate a shockwave at all.

Which might be a difficulty for a car. It would mean that low throttle might not actually be possible, there would be a certain minimum thrust level. I suppose that it could be engineered around by rigging it so that the brakes drag until the throttle is depressed a certain amount though. As long as the minimum thrust level wasn't stupidly high it's probably not really a hindrance.

P.S. Probably overoptimistic? Lol.

 

[FoRiZon]

These are the previous jet cars by GM:

 

[Oyashiro-sama]

Tch, 900hp with lasers... I could create an engine that would generate over 9000hp with a single fart from the driver. In the paper, that is

 

[vasiliflame]

There was the skylift or space lift nasa was attempting to build well they had a small scale version about 20 meters high they tested and that was laser powered basically they fired a laser at tin foil and that propelled the lift skywards via pulses , i seen the footage and it worked and they worked out a full scale version would be about 2 tonne's for the lift so they could supply the space station ..... i am thinking its this concept this car uses accept horizontal accept vertical

i cant find the actual test on you tube but this is something very similar using lasers

 

[sk8er913]

That's pretty nifty. Megawatt lasers to launch a 1kg payload, but it's certainly an awesome concept.

I wonder how well it scales down though. There's a limit to how well the laser will focus based on the stability of the whole rig and the accuracy with which they can manufacture the focusing optics. While scaling it up probably just results in bigger and bigger shockwaves, at some point when scaling down it will simply stop reaching the temperatures required to generate a shockwave at all.

Which might be a difficulty for a car. It would mean that low throttle might not actually be possible, there would be a certain minimum thrust level. I suppose that it could be engineered around by rigging it so that the brakes drag until the throttle is depressed a certain amount though. As long as the minimum thrust level wasn't stupidly high it's probably not really a hindrance.

P.S. Probably overoptimistic? Lol.

As you see for the VGT though, the casing is a lot bigger which means a lot more thrust(and more efficient) thrust. And also the tech in that video was designed in the mid 90s. I'm sure there have been some nice innovations since then, I wouldn't be that suprised if they said the 670 kw laser could produce 300 horsepower, but saying that the 670 kW laser produces 671Kw worth of hp makes me go. I'm sure their best fleet of engineers worked on this.


edit:
We missed something look at it again. I don't think its saying the laser gives it 900 hp of thrust. and an air-powered generator. It has a Hydrogen engine too, that's 2 engines. That's an interesting combination as both are rare. The failed garage 56 entry of (2013?) Le Mans ran on a hydrogen engine.

 

[Aphelion]

As you see for the VGT though, the casing is a lot bigger which means a lot more thrust(and more efficient) thrust. And also the tech in that video was designed in the mid 90s. I'm sure there have been some nice innovations since then, I wouldn't be that suprised if they said the 670 kw laser could produce 300 horsepower, but saying that the 670 kW laser produces 671Kw worth of hp makes me go. I'm sure their best fleet of engineers worked on this.


edit:
We missed something look at it again. I don't think its saying the laser gives it 900 hp of thrust. and an air-powered generator. It has a Hydrogen engine too, that's 2 engines. That's an interesting combination as both are rare. The failed garage 56 entry of (2013?) Le Mans ran on a hydrogen engine.

So this could actually be possible? Stupid, expensive, but possible?

 

[Imari]

We missed something look at it again. I don't think its saying the laser gives it 900 hp of thrust. and an air-powered generator.

I took the air powered generator to mean that it has basically a windmill on there somewhere. Which seems daft, because it's almost certainly going to be less efficient than simply running a generator off the braking system. But I guess the advantage is that it doesn't mess around with brake bias and such in the way that caused Formula 1 such problems.

It has a Hydrogen engine too, that's 2 engines. That's an interesting combination as both are rare. The failed garage 56 entry of (2013?) Le Mans ran on a hydrogen engine.

Have you got a link for that part? I've just been reading the GTP news post, which doesn't mention that part.

I guess it depends whether it's a hydrogen fuel cell which would just be generating more electricity to feed through the laser, so the laser power would still be the limitation. Or whether it's a turbine or combustion engine in it's own right generating torque at the wheels. That would at least provide additional drive to compensate for inefficiencies in the laser, making their numbers somewhat more plausible.

So this could actually be possible? Stupid, expensive, but possible?

Sort of kind of not really. The engine they describe exists and possibly could be made to work on a car, as long as propelling a car with shock waves didn't turn out to cause massive handling issues and/or simply destroy the car. There's probably no way that they could fit a laser of that sort of power to a reasonable sized vehicle, or get it to put out that sort of power for significant periods of time without massive cooling, or get the sort of efficiencies that they're talking about, and then there's the issue of how long you could feed it energy for with the restricted room you'd have for batteries/hydrogen.

It would almost certainly be very slow, very short range and much, much bigger than the images if they actually tried to build it with the technology available today, even with an unlimited budget. Such is my understanding, but I could be wrong. There's nothing physically impossible about it (with the possible exception of their 100% efficient thrust system), but it's beyond current tech to build it to that sort of size and performance.

i cant find the actual test on you tube but this is something very similar using lasers

The space elevators usually ascend on the actual cable. If you've got a cable that can hold 100 miles of it's own weight, adding a little bit extra in the weight of a carriage isn't a problem. I've seen designs where the lasers are used as an easy way to transfer power to the motors of the carriage, but the lasers themselves haven't provided propulsion in any space elevator designs I've seen.

I'm not sure what would be the point of the cable if the lasers were propelling it. The cable can't provide lateral stability, and if it's not helping vertically then I'm not sure it has any purpose in the design. It seems a waste of a 100 mile nanotube cable if it's not hoisting something.

 

[Aloha62_2]

The laser to provide the heat would be the size of another car and the power generator to power it would be the size of a truck and the final outcome would be a flash of light so bright everyone watching the race would be blinded and a 'car' reduced to a pile of burning carbon fibre.

It would of been easier to simply claim that the car is powered by a warp core and thrust is provided a immense stream of BS.

 

[Aphelion]

The laser to provide the heat would be the size of another car and the power generator to power it would be the size of a truck and the final outcome would be a flash of light so bright everyone watching the race would be blinded and a 'car' reduced to a pile of burning carbon fibre.

It would of been easier to simply claim that the car is powered by a warp core and thrust is provided a immense stream of BS.

i fail to see how that would have been easier.

 

[Third Reign]

Being a laser freak myself I also asked myself how the efficiency side of a "laser propulsion" system would look like. Diode lasers have a at best ~70% efficiency going from electric to optical power. Solid state lasers are significantly worse in energy conversion. Achieving high optical output powers is quite easy with pulsed lasers, but I have no idea how they plan to convert the optical power to mechanical power/torque and how efficient the conversion is. I highly doubt it will be more efficient than combustion methods. But I guess the word Laser itself carries a myth and fascination that lets ideas leap the bounds of the currently possible.

Current optical propulsion systems I know of only have very low acceleration values, but for long space travels this acceleration can be kept up continuously to very high velocities.

 

[Imari]

Current optical propulsion systems I know of only have very low acceleration values, but for long space travels this acceleration can be kept up continuously to very high velocities.

Yeah, it's less of a light pressure type method and more like Project Orion, where the idea was to launch miniature explosives or nukes behind the spacecraft and have them propel it. With this they're using a laser to superheat a pocket of air to create the "explosion", but the general idea seems remarkably similar.

Project Orion worked, as far as it was tested, although it obviously never became a thing. It's an interesting read if you're into this sort of stuff.

http://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

 

[vasiliflame]

I took the air powered generator to mean that it has basically a windmill on there somewhere. Which seems daft, because it's almost certainly going to be less efficient than simply running a generator off the braking system. But I guess the advantage is that it doesn't mess around with brake bias and such in the way that caused Formula 1 such problems.



Have you got a link for that part? I've just been reading the GTP news post, which doesn't mention that part.

I guess it depends whether it's a hydrogen fuel cell which would just be generating more electricity to feed through the laser, so the laser power would still be the limitation. Or whether it's a turbine or combustion engine in it's own right generating torque at the wheels. That would at least provide additional drive to compensate for inefficiencies in the laser, making their numbers somewhat more plausible.



Sort of kind of not really. The engine they describe exists and possibly could be made to work on a car, as long as propelling a car with shock waves didn't turn out to cause massive handling issues and/or simply destroy the car. There's probably no way that they could fit a laser of that sort of power to a reasonable sized vehicle, or get it to put out that sort of power for significant periods of time without massive cooling, or get the sort of efficiencies that they're talking about, and then there's the issue of how long you could feed it energy for with the restricted room you'd have for batteries/hydrogen.

It would almost certainly be very slow, very short range and much, much bigger than the images if they actually tried to build it with the technology available today, even with an unlimited budget. Such is my understanding, but I could be wrong. There's nothing physically impossible about it (with the possible exception of their 100% efficient thrust system), but it's beyond current tech to build it to that sort of size and performance.



The space elevators usually ascend on the actual cable. If you've got a cable that can hold 100 miles of it's own weight, adding a little bit extra in the weight of a carriage isn't a problem. I've seen designs where the lasers are used as an easy way to transfer power to the motors of the carriage, but the lasers themselves haven't provided propulsion in any space elevator designs I've seen.

I'm not sure what would be the point of the cable if the lasers were propelling it. The cable can't provide lateral stability, and if it's not helping vertically then I'm not sure it has any purpose in the design. It seems a waste of a 100 mile nanotube cable if it's not hoisting something.

cable was only there to direct it due to winds etc and to stabilize the laser on target ... trust me i cant find the video but the lift was only a box no mechanisms in there the bottom was covered in a tinfoil type of dooo da laser pulsed the box up litrally firing at the bottom ... the cable it essential for accurate deployment other wise it be a laser missile ... it has nothing to do with cable weight its all to do by laser power if the laser has to lift it through our atmosphere . the cable is kept in a stationery orbit , space has no gravity but planets do. it was all about pulses not a constant laser ... think of it as a pulse jet amazing power but in short burts

 

[super_gt]

The laser to provide the heat would be the size of another car and the power generator to power it would be the size of a truck and the final outcome would be a flash of light so bright everyone watching the race would be blinded and a 'car' reduced to a pile of burning carbon fibre.

It would of been easier to simply claim that the car is powered by a warp core and thrust is provided a immense stream of BS.

 

[Imari]

cable was only there to direct it due to winds etc and to stabilize the laser on target ... trust me i cant find the video but the lift was only a box no mechanisms in there the bottom was covered in a tinfoil type of dooo da laser pulsed the box up litrally firing at the bottom ... the cable it essential for accurate deployment other wise it be a laser missile ... it has nothing to do with cable weight its all to do by laser power if the laser has to lift it through our atmosphere . the cable is kept in a stationery orbit , space has no gravity but planets do. it was all about pulses not a constant laser ... think of it as a pulse jet amazing power but in short burts

Find your source. All I can find is stuff where the laser is used for power transmission, like this:

http://www.telegraph.co.uk/science/space/6507585/Laser-powered-lift-wins-Space-Elevator-Games.html
http://images.spaceref.com/docs/spaceelevator/SE_Ideal_App_for_FEL.pdf

I don't see what advantage your laser propelled system would have over a mechanically driven system ascending the cable. Kind of like how I'm not entirely sure how this laser propelled VGT is actually an improvement over a combustion engine, no matter how cool it may be.

 

[Aphelion]

Find your source. All I can find is stuff where the laser is used for power transmission, like this:

http://www.telegraph.co.uk/science/space/6507585/Laser-powered-lift-wins-Space-Elevator-Games.html
http://images.spaceref.com/docs/spaceelevator/SE_Ideal_App_for_FEL.pdf

I don't see what advantage your laser propelled system would have over a mechanically driven system ascending the cable. Kind of like how I'm not entirely sure how this laser propelled VGT is actually an improvement over a combustion engine, no matter how cool it may be.

the advantage: it looks cool.

 

[vasiliflame]

Find your source. All I can find is stuff where the laser is used for power transmission, like this:

http://www.telegraph.co.uk/science/space/6507585/Laser-powered-lift-wins-Space-Elevator-Games.html
http://images.spaceref.com/docs/spaceelevator/SE_Ideal_App_for_FEL.pdf

I don't see what advantage your laser propelled system would have over a mechanically driven system ascending the cable. Kind of like how I'm not entirely sure how this laser propelled VGT is actually an improvement over a combustion engine, no matter how cool it may be.

TBH mate i dont need to find my source its not about a space elevator anyway its about laser propulsion the theory of how this car would work... forget the cable. I have seen it with my own eyes work it was on a documentary on channel 4 (uk) laser can move a object trust me and at a fast rate but only via huge powerful pulses. not mean to sound rude but seems the space lift thing is distracting from the theory of the power plant for a road vehicle

 

[TurismoBad]

 

[MatskiMonk]

The real question for me is not how plausible the concepts are, just would it achieve the kind of results GM are indicating, and is it the most practical and efficient way of achieving the performance. What's the benefit of using this system in a car?

Pretty sure If I had 100,000,000 in the bank I could get someone to build me an X20xx car that would achieve it's stated numbers... could somebody actually say today, yes I could make the 2X and it would perform (anything) like it's billed as doing?

 

[niky]

Next up: Ford's Vision GT: Orion Pax

It's a pick-up truck powered by nuclear bombs dropped out the tailgate. Press the accelerator, a bomb drops out the back. The tailgate/blast-shield goes back up... bomb detonates. 0-200+++ mph in about 0.5 seconds.

Say goodbye to your lunch. And your intestines. And the rest of your internal organs. And...

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Oh, and it's painted red and blue, and the horn button plays "The Touch" in the game.

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Incredibly silly concept... and pointless. You could have simply said the VGT was powered by jets, and you'd get the same effect. Never mind that "900 hp" of thrust going out into the air instead of to the ground isn't going to get you to 60 mph in 1.5 seconds.

Interesting that the designers say the driver's in a prone position in there. I assume the laser is surgically implanted up his rectum?

 

[Aphelion]

Next up: Ford's Vision GT: Orion Pax

It's a pick-up truck powered by nuclear bombs dropped out the tailgate. Press the accelerator, a bomb drops out the back. The tailgate/blast-shield goes back up... bomb detonates. 0-200+++ mph in about 0.5 seconds.

Say goodbye to your lunch. And your intestines. And the rest of your internal organs. And...

-

Oh, and it's painted red and blue, and the horn button plays "The Touch" in the game.

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Incredibly silly concept... and pointless. You could have simply said the VGT was powered by jets, and you'd get the same effect. Never mind that "900 hp" of thrust going out into the air instead of to the ground isn't going to get you to 60 mph in 1.5 seconds.

So?

 

[vasiliflame]

The real question for me is not how plausible the concepts are, just would it achieve the kind of results GM are indicating, and is it the most practical and efficient way of achieving the performance. What's the benefit of using this system in a car?

Pretty sure If I had 100,000,000 in the bank I could get someone to build me an X20xx car that would achieve it's stated numbers... could somebody actually say today, yes I could make the 2X and it would perform (anything) like it's billed as doing?

I could build it .... do you want my bank details? but i could build one if i had a budget.. But yeah Gm are blowing bubbles from there hoop it reminds me of the nike car slightly. batteries alone be bigger than the car

 

[dddsprayshop]

I don't see the problem. I can see it, but i see what happened.
It is Vision GT, so based on Vision or future ideas.
Some of the vision cars are really made, but others are science fiction or better "concept".

I don't care if the Laser moves the car at 900HP, i mean, in the game we can race on the moon?
Like that's going to happen in real life:"Houston? we take a coffee break, we put some cone's on the surface and run them down".

I take it serious if a Laser propelled car is on a car program and shows to the world what is possible.
Untill then, it is just vision..

 

[niky]

So?

Gran Turismo once gave us the Nike 2022 concept, which was supposed to be powered by "bioenergy"... I'm down with that. Nike knew it was hokey. We all knew it was hokey. No problem. Agent Smith will escort you to your car now, Neo.

Here, Chevy is proposing a propulsion system supposedly based on real science. Nuh-uh. When you claim something is possible, you've got to show your math. Thank you.

While I admit laser thrust is a cool concept, the amount of energy required to power a laser big enough to create enough thrust to achieve a 0-60 time of 1.5 seconds is so large that you could simply put it down through the wheels and get there much faster. This also helps you get rid of the big, heavy laser needed to power such a contraption.

There's a good reason why launch lasers are stationary, and the vehicles they launch don't carry lasers with them. It's only when you scale up to large spacecraft launching in... space... that it makes sense to put a laser on-board.

A bomb-powered car is much more believable. And we can build one right now... just not... uh... with nuclear bombs.

It's not that such propulsion systems are far, far off into the future. It's that it's a Rube Goldberg device. Utterly impractical.

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Yeah, I was a grouch when watching both "Armageddon" and "The Day After Tomorrow", too. Thank you.

 

[Aphelion]

Gran Turismo once gave us the Nike 2022 concept, which was supposed to be powered by "bioenergy"... I'm down with that. Nike knew it was hokey. We all knew it was hokey. No problem. Agent Smith will escort you to your car now, Neo.

Here, Chevy is proposing a propulsion system supposedly based on real science. Nuh-uh. When you claim something is possible, you've got to show your math. Thank you.

While I admit laser thrust is a cool concept, the amount of energy required to power a laser big enough to create enough thrust to achieve a 0-60 time of 1.5 seconds is so large that you could simply put it down through the wheels and get there much faster. This also helps you get rid of the big, heavy laser needed to power such a contraption.

There's a good reason why launch lasers are stationary, and the vehicles they launch don't carry lasers with them. It's only when you scale up to large spacecraft launching in... space... that it makes sense to put a laser on-board.

A bomb-powered car is much more believable. And we can build one right now... just not... uh... with nuclear bombs.

It's not that such propulsion systems are far, far off into the future. It's that it's a Rube Goldberg device. Utterly impractical.

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Yeah, I was a grouch when watching both "Armageddon" and "The Day After Tomorrow", too. Thank you.

I understand that but, so? Why care? Tell me, why do you care?