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UAV Hoisted Tower Powered By Laser Over Fiberoptic
carstene writes "LaserMotive, winners of the 2009 NASA power beaming contest, has a new invention, a virtual comm or surveillance tower. It's a quadcotper that can run indefinitely, powered by laser beam over a fiber optic cable. This allows the "tower" to reach great heights and avoids most laser safety issues."
...is that you have to retract the UAV during a storm. While it's retracted, you've lost the UAV's capability. So, I can see these deployed in emergencies when you need comms fast. But eventually you'll want to build a tower.
Finding God in a Dog
Copper weighs more than a fiber optic cable.
Atlanteans had this tech back in the 10,000 BCs except they didn't bother with a tether, they just beamed their maser (that's Microwave amplified...) energy through crystals seated on top of large pyramidal buildings. We're so 20,000 years ago.
Fiber is non conductive. If you are going to fly your little drone in a populated area, you don't have to worry about your tether contacting overhead power lines. A lot of cranes and hoists used to have fiber to the remote controls for that reason. (A lot of them are wireless now).
None of them can see the clouds; The polished wings don't care.
Tethered ground-powered rotor-lift platforms date back to WWII. Israeli Aircraft Industries has one in their product line today. They're usually installed on the back of a vehicle, so you can pop up the camera unit and take a look over the next hill. Early versions had no guidance and just used enough power to pull the tether taut. Modern ones fly actively, so they can be used to peek around buildings.
Using a fiber optic to transmit power is rather inefficient. Probably 70% - 80% of the power is lost that way.
Why not just use a balloon? The only advantage I can see this having is less movement due to wind, but designing a properly shaped balloon should easily defeat that, and more importantly a balloon would be much quieter at low altitudes, use much less power, and stay aloft even if the power is cut. Seems like a case of a hammer looking for a nail.
There is no such thing as non-conductive - all depends on the voltage applied. It will become very conductive once the lightning strikes it.
One of the advantages of this design over a lightweight copper power feed is that DATA is bidirectional over the same optic cable. Transmitting the surveillance data back to the ground is much more secure and at higher rates than through thin copper or over some RF transmitter on the copter. That is, this can be stealthier.
Help! Help! I'm being repressed!
Well, as long as they're ill-tempered. That's the important bit.
Because a balloon, at best, is filled with Hydrogen, and doesn't carry a lot of weight. This is for surveillance, possibly covert. Flying a giant balloon from a ground station in a forest outside a Colombian drug lord hideout wouldn't be the wisest move.
A copter on the other hand can be small, nearly silent, and left heavier equipment without nearly the visual footprint. It can also be rapidly deployed and returned for "quick looks". It can be taken to an exact height and location, not blowing around, and would not need tanks of gas brought around with it... A laser hooked up to a generator would eventually be safer and more portable and reusable in a battle or disaster.
It would also be much easier to remote control, turn the camera. What use is a balloon at say, a nuclear disaster zone like Japan, if the camera isn't stable enough to actually zoom in remotely without making the operator throw up?
I8-D
I was actually hoping that wireless transmission of power didn't mean there was some sort of big cable connecting the transmission endpoints. But I see there are just no wires in the big "wire" that connects the drone to the ground.
Uh! No! Don't know you reading a 3 sentence paragraph qualifies all of us arm-chair EEs to know exactly where 12 cent parts can save billions for an application we know nothing about?!
If I can just reach out with my words and touch a butthole, just one, it will all be worth it.
The critical factor behind InvisiTower is laser power beaming, which involves the wireless delivery of electrical power over long distances via laser beam ... In this case, laser light is beamed through the fiber optic cable and converted into electricity at the aerial platform.
Um. The phrase "wireless" must mean something completely new.
It must have been something you assimilated. . . .