A set up of harnessed Lithium Polymer Cells can be the answer to mini-UAVs. When we compare the voltage output and capacity of wire harness systems and compare the weight of LiPoly cells to NiCd or NiMH cells you can achieve extremely better results than the average fuel and output on a ounce per ounce basis. http://plantraco.com/hobbies/product-lpcells.html It is also a re-useable issue that the batteries can be recharged and if the glide ratio of the UAV-mini is decent, you could use a slight shallow glide under lower power as batteries discharge to get the unit back home even when the aircraft is no longer able to actually climb or maintain altitude. Although we are still unconvinced that this system is the best, we believe a battery system of some material may be the best bet. For instance the cell phone industry has done wonders and if you delete the plastic case, thus you are even lighter. And a small solar panel of ultra thin skin might be able to even recharge the battery for the return flight, if such is a required return mission for re-use. Many of the little motors in model airplanes have good advantages. The technology advances on batteries due to the funding of computer tech companies have benefited the possibilities of UAV electric re-usable, rechargeable and re-coverable craft. http://www.npaci.edu/online/v6.15/batteries.html Some of these plastic and Poly-metal-lithium mixes are just too great to pass up. The way I see it is that once the craft is aloft at altitude needed a thin microfilm, solar cell can be unfolded and used to keep the craft up and charge the battery. Perhaps adding hours to the flight. http://www.grc.nasa.gov/WWW/RT1999/6000/6920kerslake3.html A super thin solar cell only microns thick can rest upon the top of the wings and even become the wings. For instance the high-pressure area above the wing can be made of the thin film of 2-3 microns, which the bottom be made of composite or molded foam of such materials as stealth aircraft. You will then be talking about an aircraft-UAV that has a weight of 4-6 pounds with a payload of 10-11 pounds and on a sunny day can fly for 10 hours or more. I even bet you could fly one around the world or across the Pacific all you need it to get up to the Jet Stream under electric power and charge your way across the ocean. |
