Considering that the batteries were recharged to a higher degree than when the test began, I imagine that laser beacons could be trucked out to various areas that could allow a Stalker to venture off on battery power and then use these remote stations to recharge when it would be too hostile of a space for a laser beacon to actively supply energy during a mission and outer-space-treaties prevent us from using lasers from orbit.

I suspect that it'd be a pretty expensive way to power a car (or a plane, for that matter).

I disagree, Alan. Today, yes. But with sufficient research, I don't see why this couldn't be used to power an electric car reasonably cheaply. It just a matter of how much effort we are willing to put into it, and it seems that the military is going to be a doing a lot of the hard thinking for us already.

I would put this in the "very exciting" category. Above all, there's no need to carry a battery or fuel. Just the conversion mechanism. This could be installed on roadways and it can just be line-of-sight. I would think it could make cars almost as efficient as trains.

How would you like a 100 kW stray laser beam hitting you and your vehicle?

Or, how about that Airlines pilot getting hit with a "stray" laser beam when he is approaching the landing strip ?

The skies are getting crowded enough the way it is, and everyone wants a toy in the sky.

1 gallon is about 3.78 liters, so the average 20 gallon gas tank contains about 75 liters of gasoline. Most cars have a driving range somewhat less than 400 miles, so at highway speeds, it takes about 6 hours or 21,600 seconds to empty it. That means that the average car burns about 3.5 milli-liters per second. Consider that most of the energy in the internal combustion engine is used to heat the engine, and electric engines are far more efficient. In addition 75% of the car is the engine itself and the fuel it has to carry.

I'd suggest that the amount of needed energy for one car is about equivalent to burning, per second, enough gasoline to cover your thumbnail. That's enough to give you a nasty burn if sufficiently concentrated. It's not enough to vaporize you and your car.

The line of sight visibility at human height is 8 miles. You shouldn't have cars less than 50 feet closer to each other, so the maximum needed energy capacity is 16 miles / 50 feet. This means that if they are all able to aim at you, you could get 1600 of them aimed at you. That's like pouring 1/3rd of a gallon per second onto the top of your car and setting it on fire. That's very dangerous, but not even necessarily lethal, you can stop and just run away.

And, of course, it's possible to take all sorts of precautions, such as making sure that it's physically not possible to aim any laser farther than a few hundred feet away, just don't allow it to rise very far towards the horizon.

maybe if you drove over little powerful pulsed laser that were triggered by a requesting mechanism and they were placed every so many feet where ever there was civilized road.....uh, starting to sound like Heinlien...and I am a darned asimov fan at that....uh oh...

I wonder if they are also considering modulating the laser signal so that flight control commands can be sent on the laser beam as well - that would provide relatively secure communication between the ground controller and the UAV.

Sorry, Byron, the energy required to run an automobile on laser-beam-supplied energy isn't the sole limiting factor.

Imagine the infrastructure.

Maintaining lIne of sight (LOS) -- so that the laser could see and track the target vehicles -- would require satellites. (Unless you think it's practical to have lasers on telephone polls every few miles.)

With millions of vehicles on the road, you'd have to fund, build, launch, and maintain fleets of orbiting laser platforms.

And there are some obvious questions you'd have to address:

• Where would your lasers get power from? Solar? Nuclear? Perpetual motion machines?
• What impact would WEATHER have on your ability to deliver the power where it was needed?
• How, on Earth or off) do you compete with the literally MILLIONS of simpler, cheaper, more environmentally friendly and efficient methods of energy delivery?
• Etc. (Because I only thought about your proposal for two seconds, I'm guessing there are many more questions worth asking.)

In short, if you've got a drawing board, you should get back to it.

If you make 30 mpg at 60 mph, you're burning 2 ml/s, this is about volume of a fingerbone. But these 2ml pack a lot of energy, about 70 kJ. The engine makes some 30-50 kW of power during that. If you want to power it by a laser, the laser needs to transmit more than that, to compensate for efficiency.

Think of that in this way. If you have a torch that burns 2 mL of gasoline every second, that's gonna be a hell of a torch. You don't want it to touch your car or you.

I think you all are missing the big picture......... Multiple Laser's will be mounted on a Satellite and multiple planes that are launched will be powered and controlled by this Satellite using GPS to navigate not only the Plane but the Laser to the Plane, as the Satellite passes and you have the dead zone. The plane can still get it's orders while it waits for the other Satellite to refuel it. With Stealth and the small various sizes of the Planes, you could spy on a Country continuously for years.. The Weather above the clouds is always clear and presents no problems, so this can go online very quickly I think.. This is simular to what is called Swarm Technology..

@Kevo2,

I think you're missing a small picture. A satellite flies with speed about 7-8 km/s. That's a hell of speed. To keep a laser targeted on a small plane you'll need insanely precise mechanics and optics. To keep multiple lasers tracking multiple planes, it becomes a hell of a dynamics problem, because each drive will cause a reaction back to the satellite body.

Even doing that from Earth is very very non-trivial task.

Given how quickly EM radiation loses energy over distance, I have to wonder how practical this is. How much energy would we need to use to create a beam powerful enough to transmit enough energy to a vehicle? And what happens to anything else that gets in the way?

I'm not sold on this idea yet.

When it comes to something that travels on the ground, we already have proven systems to power it while underway (streetcars, trains: induction).

for something that flies for observation and communication, a solar-powered plane or dirigible might make more sense. However, this technology might allow for continuous charging at night from a ground vehicle.

I am with ya wahoo2, but I wanted to add, yepper, solar panels...nice and flat and polyunbreakable (yea, right)....and finally, the jetsons hoover car...well, only like three feet above the infrastructure...shhh...imagine it, a whole gaggle of politicians earmarked hogs feeding wet dream...new cars, new roads, new taxes lotsa public work and even msoft will find a dime in a dream....gawd...glad Im awake and can grab the erasure.....and I like the space ship spinoff too, good thing the inverse square law still applies whew, back to asimov, and thankfully so.........this tech gets a niche market and nothing more. After four decades is only beginning to mature into a viable product....note jamming is easier than one could imagine, but I'll let you doodlers figure that one out.

The article stated the beam was about 30+feet. No data given on the % of effective energy transmitted or received. Most laser generatorsare energy HOGS and I'm sure the receiver has large converson loses, also...

The US Military has been trying to field a operational laser weapon for decades, ZERO systems operation currently...

Just like the electrical coils enbeded in a road to charge EVs. The further away the receiver is the lower the available energy. For an electricial field the loses are squared when the distance is double, plus any enviromental blocks. The effective operating distence is measured in inches/mm...

Thelasers available power is effected by; enviromental moisture, clouds, suspended particles, obstical masking, distance to receiver, etc. But the largest factor in a laser is maintaining the beam on the moving receiver. Any alignment error and ALL the energy is lost. As the distances increase between the laser transmitter and receiver the loses INCREASE and alignment errors are more pronounced...

The idea is to produce the needed results, while consuming the least amount of ENERGY...

Oops the original unedited version was published. Dam computer... Ha! Ha!

I see it more as a cellular type setup with recharging towers every 10 or 15 miles that acquire the receiver on the vehicle as a target, pulse out energy to the vehicle while it's in that cell, then moves on to the next system sending out a request. Yes, a lot of infrastructure, but it could eventually make non-stop ground travel feasible.

A laser powerful enough to sufficiently charge the batteries on an aircraft flying at relatively low altitude has probably got to be a ridiculously powerful and concentrated beam.

I wonder if one of the major hurdles to creating orbiting microwave relays to transmit power from space to Earth is due to the obvious weapon-applications

Maybe they should watch the movie "wierd science" they popped popcorn from space with a laser.lol

But the Republican administration of President George Bush, arguing that the security instruments of the cold war era are past their sell-by date, appears reluctant to negotiate internationally binding arms control treaties

This is in direct correlation of star wars and SDI. I am not sure if those treaties prohibitting lasers or targeting in space still stands.

I think it was Real Genius, but anyway, the problem is getting the fuel all up there in the first place. I suppose you could use solar collectors, but those are pretty heavy. I'd think it might be easier to have a bunch of ground-based stations that aim at planes or cars, rather than the opposite.

I think because they are using a low intensity beam by comparison to what would be used in the field, and that the beam output and distance are probably adjusted for a certain scale that they imagine the maximum operating distances would be from a larger laser over orders of magnitude longer distances

This was a proof of concept to show a full sized UAV operating at ordinary capacity was able to function solely from a remote source charging it

China will have this technology by next week - if they don't already.

Agreed, though the article mentioned that the drone in question has onboard batteries that ordinarily allow it 2hrs of uninterrupted operation, and that said batteries had a greater charge at the conclusion of the laser-power test than what the craft had started out with.

But regardless, laser charging is far from efficient.

I think that in fact it might end up being more efficient to use the laser as a way to rapidly ionize the air in its path and then use said beam as a conduit with which to transmit a microwave beam within it and use the microwaves to charge rather than the photons hitting PV's. Maybe give the craft an ultra-capacitor (which can accept a charge more rapidly than a battery) and do a quick pulse to charge the craft rather than a sustained beam

Here's an article on the sub-carrier effects of lasers and microwaves

@ AD; The drone will surely refuel long before this is an issue. Back up power would also be a consideration.

How many BTUs are lost in heating up the air molecules on it's way to the drone?

??

I believe duration along with effeciency are the goal more than just efficiency.

If the beam gets deflected and/or blocked, down comes the drone.

Drones will be lost under the best of circumstances. As I explained earlier this can be lessened but not avoided. Loss of power or deflecting of beam that is. I believe a device used to put it on a certain trajectory if communications are lost would also be a solution. eg The lost drone in Iran awhile back.

the thing you are forgetting is, the UAV was operating on its batteries. the laser wasnt powering the UAV in any way, it was set up to recharge the batteries while the batteries were in use, being drained by the UAV's power demands. sort of like an alternator on a car.

and since the UAV's batteries were showing a net GAIN in power, the laser was charging the batteries faster than the UAV was using them. so if LOS was lost for an hour and a half(bad weather, topography), the UAV would still be fine as its batteries have a usage time of 2 hours. once LOS could be made again, the batteries would again, begin charging.

as far as loss of control due to loss of LOS, not an issue since the UAV's are piloted via satalite. IF and only IF cloud cover is dense enough(thunderstorm) that a UAV loses connection with the pilot, it sets itself to maintain level flight at max altitude, or diverts to a pre-programmed flightpath(usually to a location that can be recovered with minimal impact to civilians or risk to the recovery team in case connection cannot be re-established)

as far as i know of, there has only been 2 UAV's lost due to loss of connection to pilot that were made public... there may be more that hasnt been brought to the public's eye. one was recovered, the other... not so much :)

now on to someone talking about EM fields with lasers... lasers do not create, use or manipulate EM fields... they are highly concentrated exited PHOTONS. photons are particles, they do not have electrons or protons. lasers lose thier intensity over distance for 2 reasons.

1. the beam widens over distance without increasing the number of photons in the beam. this is why you cannot see a laser dot hitting the moon. by the time it gets there, the beam from a laser will be about 6 MILES wide. if a laser puts out about 10,000 photons over a 1/8 inch beam at apature exit, when it hits the target on the moon its still 10,000 photons over a 6 mile diameter area. this is far fewer photons in the same area as even the reflection of sunlight from earth hitting a new moon.

2. atmosphere. the very air that the laser will travel through will disrupt photons passing through it based on air preasure and temperature. take a hot summer day, look at a long stretch of road and watch the road 'shimmer' as the photon's path to your eyes gets alll jumbled around by the hot air rising off the pavement. the exited molecules in the air are moving at varying speeds and directions alter the path of photons minutely and randomly causing the 'shimmer' effect, this will affect lasers and their ability to lock onto a target in hot climates.

@Mystic, ... Thank you for that info, but I still say it is a wrong application for a laser. I would of thought that line the wings with efficient solar arrays that could charge the batteries by flying over the clouds. The solar arrays could also be used in the dark of night with some good ole fashion ingenuity which I cannot discuss on this forum, hint: Greeks.

Maybe solar?

As I understand the article, it is a 8" laser and the 'drone' was 30ft (9meter) away. Seems like a lot of wasted energy. Probably better off just using it to warm your pizza.

"would you like to play a game?" lol

"would you like to play a game?" lol

Nice toy, but it should be easy for anyone to see the laser using the correct glasses and shoot down the target. Any other type of transmission power would also be trackable. Microwaves would fry the plane. Sounds like they are more on track with the fuel cells. Running a laser that would power a vehicle of any size, just one vehicle would be extremely wasteful of the energy fed to it. Solid state lasers are not yet designed that can handle the power. The original power source would have to be massive solar cell banks for each vehicle, or nuclear/fossil fuel powered. In my opinion.

"Gorilla glass" with the thickness of a few microns might be part of the solution to this idea. - RC

On the other hand, a black opaque high temperature carbon fiber film on the lower half might actually make more sense. - RC

I need you all to listen to me RIGHT NOW! High energy alpha particles are the perfect means of super heating hypersonic air flows for trans-atmospheric (air breathing) propulsion systems. These high energy alpha particles can super heat these hypersonic air flows in these (SCRAM?) engines almost instantaneously as a means of developing hyper velocity trans-atmospheric throw mass or propulsion. There are both nuclear and thermonuclear means of generating these high energy alpha particles. We need to proceed with the development of these nuclear or thermonuclear powered trans-atmospheric propulsion systems RIGHT NOW !!! PLEASE,LISTEN, I BEG YOU ALL, WE NEED TO UNDERTAKE THIS DEVELOPMENT RIGHT NOW !!! - Rick Carter

Alpha Drives are potentially very critical to the future of U.S. leadership in space. - RC