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Atlas: A Human-Powered Helicopter
- Tichy 14y agoWhy aim so low? I say kickstart a perpetuum mobile!
- crazy_eye 14y agoNeat, but this idea can only go so far on this planet (gravity, etc). Maybe on our next planet...
- yurisagalov 14y agoThis project is from the same team that recently set the Guinness World Record by building a Human Powered Ornithopter (http://www.youtube.com/watch?v=0E77j1imdhQ http://www.youtube.com/watch?v=0E77j1imdhQ)
- Tichy 14y agoThat video seems weird: since apparently they launched the ornithopter with some machine, how is it even clear that it stayed afloat by using human power after launch? Where is the difference to a glider?
- pygy_ 14y ago> Where is the difference to a glider? It sustained altitude and speed for a while (short of 20 seconds). See this: http://www.youtube.com/watch?v=0E77j1imdhQ http://www.youtube.com/watch?v=0E77j1imdhQ
- jrockway 14y agoGliders can gain altitude and speed. There are plenty of spots on the surface of the earth where air is rising quickly enough to support a plane.
- pygy_ 14y agoTrue. I guess we can dismiss the possibility of ascending currents in this case, since the test was performed on uniform land, at dawn.
- marvin 14y agoGlider pilot here. That does make it less likely, but it is no guarantee that there were no rising air currents. Thermals are sustained by an atmospheric temperature differential, not "hot air rising". They are usually _triggered_ by the local temperature differences caused by the sun, but can also be triggered by a gust of wind.
- pygy_ 14y agoThanks for teaching me something. I was referring to this[0] which is indeed hot air rising and only occurs at low altitude, you're talking about this[1]. Is there a possibility for the phenomena you describe to occur 10 meters above flat land at dawn? [0] http://en.wikipedia.org/wiki/Thermal http://en.wikipedia.org/wiki/Thermal [1] http://en.wikipedia.org/wiki/Thermal_wind http://en.wikipedia.org/wiki/Thermal_wind
- marvin 14y agoHi, sorry for the late reply. I only briefly read the second link, but I don't think it's what I was talking about. I read the Wikipedia article on thermals a week ago, and it seems a bit brief. I was a bit quick with my first reply as well. This is a pretty big subject. Thermals can be triggered by any perturbation in the atmosphere - a gust of wind, a truck on the highway or a temperature differential caused by the sun. But they are _sustained_ by vertical temperature differences in the atmosphere: As an airmass rises, it expands due to the lower atmospheric pressure. This expansion causes the airmass to cool adiabatically, approximately one degree Celcius per 100 meters of gained altitude. However, meteorological conditions can cause the temperature distribution of the _surrounding_ air to be different. For instance, after a clear night with no clouds, perhaps the air from the ground up to 2000 meters altitude actually decreases in temperature 1.1 degrees Celcius per 100 meters of altitude gained. If an airmass on the ground starts moving upwards in these conditions, it will still cool adiabatically - but slower than the rest of the atmosphere cools due to the meteorological conditions. So a rising airmass will actually accellerate, because the airmass grows hotter relative to the surrounding air as it rises. This is a thermal. It will keep moving until the temperature of the atmosphere starts rising with altitude. Condensation (cloud formation, cumulus clouds are caused by thermals) can increase its vertical speed. But to answer your initial question: Yes, they can and do. But when the atmosphere is so _unstable_ (unstable atmosphere == temperature falls very quickly with altitude) that thermals are spontaneously triggered without help from the sun, it will usually mean bad weather or thunderstorms later in the day. So if the air seems calm at the surface, it will pretty much be guaranteed to be calm at 10 meters altitude. You can detect thermals at ground level by rapidly changing wind direction, often on nice summer days. In the air at low-ish altitudes (less than 2000 meters), thermal activity is indicated by turbulence.
- rorrr 14y agoThat's not human powered, they accelerated it with a car. It's like saying hang-gliding is human-powered.
- sopooneo 14y agoBy that reasoning, Yeager's X-1 was not rocket powered since it was launched from the bomb-bay of a flying B-29 prop plane. And a hang glider isn't powered at all. It has no thrust.
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- recursive 14y agoDoes partially human powered work better for you? Human powered implies that a human generated all the power needed for takeoff.
- grannyg00se 14y agoIt's kind of a tricky bit of language because a hang glider actually is human powered if you consider how its direction is changed and how it stays aloft. The human isn't just cargo sitting there doing nothing. Without the human "powering" the hang glider it wouldn't stay aloft if you simply pushed it off of a cliff. If you are specifically looking at thrust that is easier to talk about. In general, I wouldn't call a hang glider human powered either even though a certain amount of human power output is responsible for its sustained flight. This is in contrast to a craft with a non human power plant. Even in cases where the human is using some kind of power output to further assist the aircraft, the output of the power plant is several orders of magnitude larger than the human's output. Which in some cases may be simply moving a control mechanism. And then there are what could be referred to as human "assisted" craft where the human power output is actually equal to or close to the output of the non human power plant. I think the human assisted craft are more likely to be reasonably useful. We're just not suitable for the type of sustained power output that is required for fully human powered flight.
- adamgravitis 14y agoBoth Todd and Cam are brilliant aero engineers. While not a fait accompli, this certainly isn't their first negotiation with nature...
- joachimd 14y agoWow competition is heating up as there is already a well established group called Upturn going after the prize. They also have a Kickstarter campaign and are much further along with a working model that is now getting tuned. http://www.kickstarter.com/projects/1594333219/make-aviation-history-with-a-human-powered-helicop http://www.kickstarter.com/projects/1594333219/make-aviation...
- RusAlexander 14y agoI don't have a Flash Player. need a youtube HTML5 video link.
- starpilot 14y agoWow. I spent most of my undergrad extracurricular effort working on my university's HPH team. Incredibly difficult challenges in aerodynamics and structures. The goal is to go for a whole minute and reach 3 m altitude. In the few decades the prize has been offered, the record has been seconds and centimeters high.
- option_greek 14y agoI can understand the altitude limitation but whats limiting hover time.. losing balance ?
- carlhu 14y agoInsufficient sustainable power output.
- archangel_one 14y agoPresumably the pilot must be pedalling pretty hard to get this thing in the air, so they're not going to be able to keep that up forever.
- smackfu 14y agoIt may help to see a video: http://www.youtube.com/watch?v=q70tM5sDQhc http://www.youtube.com/watch?v=q70tM5sDQhc They are right on the edge of flight/no flight. The driver is pedalling flat out and it's not flying. Then it hovers for a few seconds, then it goes back to on the ground.
- Unoeufisenough 14y agoIs storing energy against the rules? for example pedaling for an hour or two to store up say mechanical energy in a flywheel, spring tension, hydraulic pressure or other means then just put the rotors in gear to lift off?
- heretohelp 14y agoI have to assume so. Leverage is presumably allowable though. Once you're in the business of storing mechanical energy, you haven't solved the problem of sustained human-powered flight and you're really just a technology epoch away from using a motor and a capacitor.
- alagu 14y agoOn some guesses of how future will be, I definitely see jetsons-type single/two person local commute micro-aircrafts. Curious, who else is working on micro-aircrafts with engines for local commute?
- netrus 14y agoI always fail to see the market there. Why is it superior to the car, considering the higher costs for fuel, that will be unavoidable?
- fredsters_s 14y ago"unavoidable" :-|
- rprospero 14y agoIt depends where you live. I regularly make a 35 mile drive to a place that's only twenty miles away. A vehicle that used 75% more fuel per mile than my car could let me make the same trip in almost half the time for the same amount of fuel.
- alagu 14y agoMarket is where land commute takes time. Eg., in Bay area, there are lot of people who commute from South Bay to San Francisco. Slow traffic is common during peak hours and it is frustrating. I see this area as one of the best places to try local air-commute. It would add the third dimension to the commute space. Like the fast-lanes in freeways, lanes could be formed by altitude.
- suby 14y agoI think a far more likely solution / scenario is that we'll have cars that drive themselves. It'd also be a hell of a lot safer.
- K2h 14y agoMore pictures of the streamlined high-speed recumbent bicycles at http://www.flickr.com/photos/adamince/page2/ http://www.flickr.com/photos/adamince/page2/
- suhastech 14y agoInteresting. The first project they seem to have funded on Kickstarter. http://www.kickstarter.com/projects/1594333219/make-aviation-history-with-a-human-powered-helicop?ref=users http://www.kickstarter.com/projects/1594333219/make-aviation...
- joachimd 14y agoThat is a different project, different set of people.
- reledi 14y agoCameron and Todd backed the Upturn project on Kickstarter, they didn't create it. NTS Works (the organization behind Upturn) is in competition with AeroVelo (the organization behind Atlas).
- jonah 14y agoThis guy seems closer to the win. He's been iterating on this thing for years and is the current record holder. He also founded and sold Zero Motorcycles.
- obilgic 14y agothey wont get funded, just because their video does not really compete with other's
- SagelyGuru 14y agoI suggest at least eight strong men in a row. You get aerodynamic and scaling benefits, just like with rowing boats.
- xyzzyz 14y agoAir vehicles are light, men are heavy.
- SagelyGuru 14y agoIt seems a bit pointless when it would be relatively easy with a dirigible (i.e. add a bag of hydrogen or helium). On a windless day, your pedalling should propel you quite a distance anywhere you want to go. Problem solved, with technology that is at least hundred years old.
- WestCoastJustin 14y agoThe goal is to win the American Helicopter Society (AHS) prize of 250k. The regulations (http://www.vtol.org/awards-and-contests/human-powered-helicopter/hph-rules http://www.vtol.org/awards-and-contests/human-powered-helico...) specifically outlaw your suggestion -- although it was a good one ;) 4.1.1 The machine shall be a heavier-than-air machine. The use of lighter-than-air gases shall be prohibited.
- Someone 14y agoThanks for the link. It appears that you are allowed to drop the ground level from below the helicopter :-) One thing that is slightly more in the spirit of the contest is to have rotors tht do not provide lift at all and hence have low drag, build up lots of potential energy, and then adjust the angle of attack to get lift. Storing potential energy to get a 30 second launch and subsequent 30 second drop will be 'challenging', though. I guess that both will be covered by "3.2 For any and all questions regarding acceptance of entries, eligibility of an entrant, pilot, crew or aircraft under the regulations, or any other matter relating to the AHS prize, the decision of the AHS is final."
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- SagelyGuru 14y agoOK, thanks. So how about I use strong carbon fibre shell with air pumped out. There is no lighter than air gas involved and the whole machine can be (just slightly) heavier-than-air. I bet they would outlaw that too, under the 'catch all' rule mentioned below. Nothing but extremely hard work will do ;)
- grannyg00se 14y agoIt looks like the state of the art right now gives us absolutely huge devices that barely even make it off the ground. Does anybody have any confidence that a human powered helicopter could ever be practical for real transport? Unless we humans somehow manage to multiply our sustained power output by several times, I don't see this happening.