The thermal harvesting idea is one my university has been trying to figure out. We found these papers by a researcher early this year: (In no particular citation format)
Allen, Michael J.; Updraft Model for Development of Autonomous Soaring Uninhabited Air Vehicles; NASA Dryden Flight Research Center, Edwards, California 93523-0273, USA; AIAA
Allen, Michael J.; Autonomous Soaring for Improved Endurance of a Small Uninhabited Air Vehicle; NASA Dryden Flight Research Center, Edwards, California, 93523-0273, U.S.A.; AIAA
Google Scholar should have to problem getting these for you. Basically, This guy has the model for the average thermal field, and has written the matlab code for getting into these.
As to the barometric pressure sensor, I'm not sure. I've heard of ideas of using thermometers to sense thermals, but the response time was in question. One thing I know doesn't work is trying to see them, as thermals get blown around anyway, and so are not always exactly over a hot parking lot. (And most thermal cameras will break the bank.)
I believe spectroline (boeing subsidiary) makes some great solar cells that have been used for UAV's. $5,000 minimum order though, perhaps a diydrones group buy?
That combined with thermal lift could enable indefinite flight. Anyone have the link to the UAV that flew for two days and landed with full batteries? The researchers had to run shifts the whole time to look for thermals but I believe a barometric pressure sensor could find them? Combine this with an autopilot that makes a map of the location of thermals and you could have a "recharge mode" Where the plane just stays alot via thermals and solar cells then go back to "mission mode" once the batteries are full. Just some thoughts.
Bad news because I did not do anything about it but some research and now it has been patented. Although the patent has been filed in 2005 long before I had come up with the same idea :)
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The thermal harvesting idea is one my university has been trying to figure out. We found these papers by a researcher early this year: (In no particular citation format)
Allen, Michael J.; Updraft Model for Development of Autonomous Soaring Uninhabited Air Vehicles; NASA Dryden Flight Research Center, Edwards, California 93523-0273, USA; AIAA
Allen, Michael J.; Autonomous Soaring for Improved Endurance of a Small Uninhabited Air Vehicle; NASA Dryden Flight Research Center, Edwards, California, 93523-0273, U.S.A.; AIAA
Google Scholar should have to problem getting these for you. Basically, This guy has the model for the average thermal field, and has written the matlab code for getting into these.
As to the barometric pressure sensor, I'm not sure. I've heard of ideas of using thermometers to sense thermals, but the response time was in question. One thing I know doesn't work is trying to see them, as thermals get blown around anyway, and so are not always exactly over a hot parking lot. (And most thermal cameras will break the bank.)
-Steve
That combined with thermal lift could enable indefinite flight. Anyone have the link to the UAV that flew for two days and landed with full batteries? The researchers had to run shifts the whole time to look for thermals but I believe a barometric pressure sensor could find them? Combine this with an autopilot that makes a map of the location of thermals and you could have a "recharge mode" Where the plane just stays alot via thermals and solar cells then go back to "mission mode" once the batteries are full. Just some thoughts.
Good, because it means I was not so crazy after all, I was thinking about the application of magnetic field around HVLs for powering/charging a small UAV a few months ago specially after seeing this http://www.scienceprog.com/the-bright-field-with-thousands-of-fluor...
Bad news because I did not do anything about it but some research and now it has been patented. Although the patent has been filed in 2005 long before I had come up with the same idea :)
http://www.freepatentsonline.com/7398946.html?query=us+7%2C398%2C946
The patented idea is the procedure and the respected mechanism as a whole, not the idea of recharging uavs from powerlines in general.