I was intrigued to read that the US Army is looking at ways to recharge battery-powered drones (UAV's) in flight.
In a bid to revolutionize unmanned aerial vehicle (UAV) operations, the US Army has patented a new technology that can keep its drones in the air forever.
. . .
The idea is simple: recharge a drone or multiple drones during their flights, just like mid-air refueling for jets.
Based on the patent document, the new technology includes a system for deploying a powered drone tether.
Various mechanisms are included to connect and disconnect rechargeable drones during flight.
A top drone can carry a special rope to extend it from a base station supplying power. This allows one or more rechargeable drones to connect for charging and then detach to perform independent flights.
There's more at the link.
This appears to have all sorts of possibilities. If they can do it for drones, could they do it for full-size aircraft? What about helicopters? (I can see the rotor having all sorts of interesting effects on a dangling power cable!) How much power can be transferred, how quickly? How many drones can be recharged simultaneously through a single dangling cable?
All of these questions are intriguing, but with the technology in its earliest stages, I guess it'll be years before we have answers. All I can say is, based on events over the past couple of days, it might be best if Israeli engineers were not involved in the design . . . or the recharging might become a high-energy event! (You should pardon the expression.)
Peter
Not immediately, but down the road a ways, I can see beamed power(via microwaves or something to that effect) being used to recharge. This probably won't happen before the end of the decade, although I suspect that DARPA has some interesting projects going on.
ReplyDeleteI believe that the Canadian government funded a study on powering satellites using ground based microwave beams in the '90s. That might not be useful in a military drone as reflected microwaves would become a homing signal for a missile with the right sensor in its nose.
DeleteFor medium sized and larger drones, a small motor-alternator set may be superior. Liquid fuels have multiple times the energy per weight of batteries. Gasoline has twice the energy content of alcohol fuel, diesel has great efficiency. Inflight refueling is done every day, somewhere.
ReplyDeleteA letter in a recent issue of Aviation Week noted the weight of batteries, and the lower energy density, affecting performance. I agree with Ritchie about the small motor-alternator set being a good option, particularly if most of the parts can be fabricated from lighter weight compounds. And there was something about carbon fiber matrices being able to hold electrical charges, which may foreshadow a new generation of batteries.
ReplyDeleteNow that I think of it, the possibility of using a small turbine engine /alternator is very interesting. Now, small turbojets are sold over the counter in hobby shops. Not cheap, but they are there.
ReplyDeleteI'd bet it would be lot cheaper and easier to just buy and operate 2-3 times as many drones, working in relays to maintain coverage. Engines burning fuel are waay more sensible than batteries.
ReplyDeleteIt's all fun and games, until you realize the pedals at your feet are for energy generation in-flight, and a passenger trip finally becomes exactly the same as a voyage as a galley slave, pulling on an oar.
ReplyDelete