Inventor and physicist Thomas Senkel created an Internet sensation with the October 2011 video of his maiden—and only—test flight of a spidery proof-of-concept 16-rotor helicopter dubbed Multicopter 1. Now the maker of the experimental private aviation craft, the European start-up e-volo, is again with a revised “volocopter” design that provides two extra rotors, a serial hybrid drive and long-term plans for going to 100% battery energy.
The brand new design requires 1.8-meter, 0.5-kilogram carbon-fiber blades, every paired with a motor. They’re arrayed round a hub in two concentric circles over a boxy one- or two-person cockpit.
After awarding the volocopter idea a Lindbergh Prize for Innovation in April, Yolanka Wulff, government director of The Charles A. and Anne Morrow Lindbergh Foundation, admitted the concept of the multi-blade chopper at first appears “nutty.” Wanting past the novel look, nevertheless, she says, e-volo’s idea excels in security, vitality effectivity and ease, which had been the bases of the prize.
All three attributes arrive thanks largely to evolo’s removing of traditional helicopter components. First, the energy-robbing high-mass most important rotor, transmission, tail increase and tail rotor are gone. The large blades over a standard chopper’s cabin create carry, however their mass creates a excessive diploma of stress and put on on the craft. And the small tail rotor, perched vertically out on a increase behind the cabin, retains the helicopter’s physique from spinning in the wrong way as the primary blades, nevertheless it additionally eats up about 30 % of a helicopter’s energy.
The volocopter’s a number of rotor blades individually wouldn’t create the torque {that a} single massive rotor produces, and so they supply redundancy for security. Hypothetically, the volocopter may fly with just a few as 12 functioning rotors, so long as these rotors weren’t all clustered collectively on one facet, says Senkel, the plane’s co-inventor and e-volo’s lead building engineer.
With out the enduring two-prop configuration, the craft can be lighter, making it extra gasoline environment friendly and decreasing the bodily complexity of delivering energy to the highest and rear blades from a single engine. Nor would the volocopter want an energy-hungry transmission. Actually, “there shall be no mechanical connection between the fuel engine and the blades,” Senkel says. Which means fewer factors of vitality loss and extra redundancy for security.
E-volo’s design eliminates the dependence on a single supply of energy to the blades. As a serial-hybrid car, the volocopter would have a gas-fueled engine, on this case an engine able to producing 50- to 75 kilowatts, typical of ultralight plane. Fairly than mechanically drive the rotors, the engine would generate energy for electrical motors in addition to cost onboard lithium batteries. Ought to it fail, the batteries are anticipated to supply sufficient backup energy so the craft may make a managed touchdown.
Whereas helicopters navigate by altering the pitch of the primary and tail rotor blades, the volocopter’s maneuverability will rely upon altering the pace of particular person rotors. Though extra advanced, it’s extra exact in precept to regulate a craft utilizing three to 6 redundant microcontrollers (in case a number of fails) decoding directions from a pilot utilizing a recreation console–like joystick—as an alternative of rudder pedals, a management stick and a throttle.
Wulff’s first impression in regards to the volocopter’s design is just not unusual. E-volo’s computer-animated promotional movies of a gleaming white, carbon-fiber and fiberglass craft beneath a thatch of blades recall the many-winged would-be flying machines of the late nineteenth century. This level is just not misplaced on Senkel.
“I perceive these skeptical opinions,” he says. “The design idea appears to be like like a blender. However we actually are making a protected flying machine.”
That will be progress in itself. Multicopter 1 regarded like one thing from an particularly iffy episode of MacGyver, full with touchdown gear that concerned a silver yoga ball. Senkel rode seated amid all these rotors powered solely by lithium batteries. Multicopter 1 generated a mean of 20 kilowatts for hovering and was aloft for only a few minutes.
There is a cause why the experimental craft flew briefly and solely as soon as.Senkel describes that first craft as “glued and screwed collectively.” Seated on the identical platform because the spinning blades, he says, “I used to be conscious of the truth that I shall be useless, possibly. Moreover, we confirmed that the idea works. What will we win if we fly it twice?” he asks rhetorically.
Apart from placing the pilot safely under the blades, the revised volocopter design would function largely the identical because the preliminary prototype. The design calls for 3 to 6 redundant accelerometers and gyroscopes to measure the volocopter’s place and orientation, making a suggestions loop that offers the craft stability and makes it simpler to fly, Senkel says.
The volocopter’s revised prototype beneath building may debut as quickly as subsequent spring. The primary manufacturing fashions, out there in maybe three years, are anticipated to fly for at the least an hour at speeds exceeding 100 kilometers per hour and a minimal altitude of about 2,000 meters, nonetheless far shy of normal helicopter’s regular working altitude of about 3,000 meters. “This might change our lives, however I do not anticipate something like that for 10 years,” Senkel provides.
On condition that a lot of the expertise wanted to construct the volocopter is already out there, “this concept is pretty straightforward to comprehend,” says Carl Kühn, managing director of e-volo accomplice Smoto GmbH, an organization that integrates electrical drive methods and associated elements.
Like Senkel, Kühn has modest short-term expectations regardless of his repeated emphasis on the usual nature of the expertise concerned. “I assume that e-volo may have [a prototype] plane in three years that may do the job—that it’ll carry one or two individuals from one level to a different,” he says.
The most important instant limitations look like regulatory. As an example, European aviation regulators take into account any electrical system better than 60 volts to be excessive voltage and regulate such methods extra aggressively, Kühn says. Consequently, the volocopter will function under that threshold. The craft may also must weigh not more than 450 kilograms to stay within the ultralight class, which is likewise topic to fewer authorities aviation rules, in keeping with Senkel.
The Lindbergh Basis’s Wulff says the group’s judges felt e-volo had “a better than 50 % likelihood of succeeding, or they would not have given them the innovation award.” Requested if she would line as much as fly one sometime, she says, “I certain would. It appears to be like very compelling to me.”
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