Loading ...
Sorry, an error occurred while loading the content.
 

Rubber-Band Turbines

Expand Messages
  • dave santos
    The toy rubber-band airplane is an interesting device in our AWES context. An elastomer line functions much like a storage-capacitor, storing elastic energy by
    Message 1 of 10 , Jan 26, 2013
      The toy rubber-band airplane is an interesting device in our AWES context. An elastomer line functions much like a storage-capacitor, storing elastic energy by supercoiling naturally, without the kinking damage of (hockling) over-torquing less elastic lines.

      Notice that, in principle, the toy can be driven at high-speed by wind, as a looping kiteplane, and its rotor would then wind the rubber-band, as a WECS. As it orbits, the rotor would take energy from the flow during the high-speed diving phase, and give it back during the slower climbing phase. The gravity signal amplitude in the cycle is smoothed out.

      Smoothed power can be extracted at the end of the rubber-band opposite the rotor. This leads to back to our old insight that a simple rotor and ruuberband under a pilot-kite can comprise the WECS, with the work-load at the ground, solving basic flight-stability/control. We have only explored this "bungee AWES" idea in passing, but need to test it as a simple extension of Doug's SuperTurine thinking.

      Its a bigger leap to see that a simple passive rotor on a rubberband can be designed to perform a self-induced AWES spin-cycle, winding up a rubber band for a pumping tug, and unwinding at low-drag in a recovery-phase. For example, memory polymer can enable a simple passive rotor in its working phase to progressively reduce and even reverse pitch for its recovery-phase. The rotor's working pitch would slowly recover as the "phase memory" recovered, and the rotor would repeat the pumping cycle.

      CC BY NC SA
       




    • Joe Faust
      * RubberBand/RB1/index.html * TwistMethod/index.html
      Message 2 of 10 , Jan 28, 2013
      • weimdad
        Now make it self launching and the lifters be self adjusting for chaotic winds. The drive shaft to the generator as tether makes it lighter and simpler. I ve
        Message 3 of 10 , Jan 28, 2013
          Now make it self launching and the lifters be self adjusting for chaotic winds. The drive shaft to the generator as tether makes it lighter and simpler. I've been working on similar concepts and this all seems quite exciting.




          --- In AirborneWindEnergy@yahoogroups.com, "Joe Faust" wrote:
          >
          >
          > * RubberBand/RB1/index.html
          >
          > * TwistMethod/index.html
          >
          > * Rubber-Band Turbines
          >
          >
        • dave santos
          Hi weimdad, Welcome to the Forum. Perhaps you could introduce yourself, and your related efforts, to better help each other (open cooperative model). There is
          Message 4 of 10 , Jan 28, 2013
            Hi weimdad,

            Welcome to the Forum. Perhaps you could introduce yourself, and your related efforts, to better help each other (open cooperative model). There is a lot of knowledge now compiled by us about self-launching and self-trimming kite systems, if you are looking. 

            The twisted-line-transmission method is mostly associated with Doug Selsam, with hundreds of messages covering it. In that broad context, this thread narrowly explores a known advantage of elastomer lines; better hockling tolerance.

            The bonus fun side is perhaps using a COTS rubber-band airplane toy to do AWES turbine-on-a-wing proof-of-concept studies, a job that otherwise cost Google/Makani/Joby many millions, with uncertain results, due to lack of direct comparative testing. What if AWES architectures could be confidently down-selected by just playing with toys?

            Feel free to open up precise sharing or questions about your ideas and problems in this design-space.

            Cheers,

            daveS
            KiteLab Group
             




            ==========================
            I am sorry for the Yahoo "CSNBC Jobs" Spam Virus 
            that hijacked the Contact List for this mail account. 
            Please accept this apology for any trouble caused.

            From: weimdad <chiocchio@...>
            To: AirborneWindEnergy@yahoogroups.com
            Sent: Monday, January 28, 2013 11:08 AM
            Subject: [AWES] Re: Rubber-Band Turbines

             


            Now make it self launching and the lifters be self adjusting for chaotic winds. The drive shaft to the generator as tether makes it lighter and simpler. I've been working on similar concepts and this all seems quite exciting.

            --- In AirborneWindEnergy@yahoogroups.com, "Joe Faust" wrote:
            >
            >
            > * RubberBand/RB1/index.html
            >
            > * TwistMethod/index.html
            >
            > * Rubber-Band Turbines
            >
            >



          • Joe Faust
            Close to topic: SafetyAndRopeHandlingArticle
            Message 5 of 10 , Jan 28, 2013
            • Joe Faust
              Close to topic: http://144.206.159.178/FT/521/8961/174191.pdf The hockling of cables: a problem in shearable
              Message 6 of 10 , Jan 28, 2013
                Close to topic: 

                The hockling of cables: a problem in shearable and extensible rods
                D.M. Stump*
                Department of Mathematics, The University of Queensland, St. Lucia, Qld 4072, Australia
                Received 17 August 1998; in revised form 11 December 1998
              • weimdad
                Thanks for the warm welcome Dave. I ve exchanged a few emails with Doug a few years back. I am not an engineer but an old skydiver who was on the drop zone
                Message 7 of 10 , Jan 29, 2013
                  Thanks for the warm welcome Dave. I've exchanged a few emails with Doug a few years back. I am not an engineer but an old skydiver who was on the drop zone when the first kite-like parachute was jumped, the Barrish sailwing. I always enjoyed the subtle turbulence at 500 feet and 2,000 feet and felt there was potential for capturing energy even higher.

                  25 years ago I had some ideas and in 2006 I put together 2 concepts for capturing high altitude energy and was hired by a company to explore them more fully but by the end of 2007 the economy tanked and the company's cash cow industry collapsed and I went down with it.

                  The two areas of interest were/are:

                  1) Ground based generator with governor, tether/drive shaft braided Vectran type rubber band line twisting, self-launching, self adjusting kite and a mini balloon as pilot assist and something like Doug's spinning windmills suspended beneath as the drive shaft driver. The main issues I felt to figure were chaotic wind adjustments and I believe Hurricane Charley solved it for me when the last things standing in Homestead were palm trees. The palm leaves (kites) simply adapt to the wind by inverting and returning. Palms are not rigid trees but made of fibers.

                  2) The other system is a ground based generator connected to a flywheel that is spun by the repetitive launching and retrieving of a self-launching, weather chaos adapted kite. Think of the lawn mower starter with recoil. My first job was to collapse parachutes on the drop zone so I learned it is a simple matter of making one line shorter to collapse it. Same thing with the kite, retrieve that line first at altitude, then let it out near the ground to equalize the area for re-inflation and relaunch, all automatically. Repeat. Up down, up down. If the winds stop completely the system lays on the ground or floats on the water with the mini balloon always ready to catch the next breeze to begin the self launching sequence of gradually larger kites until the main system is back flying.

                  Both of these ideas have probably been explored and I'm not sure what I can contribute to the group but as a generalist I've tried to seek out an all fiber, light weight, flexible, self adjusting to weather, simple design, self launching, mass produceable, mass manufactured, container distributed, simple, non-contraption, easily maintained off shore/on shore anchoring and electrical connection system.

                  Let's make it all happen.

                  Weimdad



                  --- In AirborneWindEnergy@yahoogroups.com, dave santos wrote:
                  >
                  > Hi weimdad,
                  >
                  > Welcome to the Forum. Perhaps you could introduce yourself, and your related efforts, to better help each other (open cooperative model). There is a lot of knowledge now compiled by us about self-launching and self-trimming kite systems, if you are looking. 
                  >
                  > The twisted-line-transmission method is mostly associated with Doug Selsam, with h
                • dave santos
                  Hi weimdad, What year did somebody jump a Barrish Sailwing? We only knew of paraglider testing. I also grew up on DZs collapsing chutes for dragging skydivers
                  Message 8 of 10 , Jan 29, 2013
                    Hi weimdad,

                    What year did somebody jump a Barrish Sailwing? We only knew of paraglider testing. I also grew up on DZs collapsing chutes for dragging skydivers in high winds (Pelican Land, Z-Hills, etc.).

                    Your intuition that useful power can be extracted from simple parachutes in a collapse-retract cycle is good. We know that both lift and drag make more-or-less equal power with kites (Loyd), and we need lift mostly to get up, then a simple drag cycle can suffice to extract power. This a "Low Complexity" approach, early favored.

                    How did you select Vectran as the best torquable fiber? Its not stretchy compared to rubber, so hockling would seem to be a damage risk,

                    daveS
                     


                  • weimdad
                    Lee Guilfoyle 1965 Lakewood Sport Parachute Center, NJ Parachutes Inc was the first sailwing. Lee is still jumping at Skydive Tampa at 79 years young.
                    Message 9 of 10 , Jan 29, 2013
                      Lee Guilfoyle 1965 Lakewood Sport Parachute Center, NJ Parachutes Inc was the first sailwing. Lee is still jumping at Skydive Tampa at 79 years young. http://www.flickr.com/photos/lee_guilfoyle/200939334/ I jumped with Jerry Irwin, Dave DeWolfe and Johnny Crews from Pelican Land and made quite a few jumps at Z-Hills.

                      I picked Vectran because I don't know any better. Whatever will be used for the future Space Elevator from nano technology developments might be better. Twisting into a "burl" like knot on the drive shaft/tether would just be stored energy until it is used by the generator as long as it would not shred.



                      --- In AirborneWindEnergy@yahoogroups.com, dave santos wrote:
                      >
                      > Hi weimdad,
                      >
                      > What year did somebody jump a Barrish Sailwing? We only knew of paraglider testing. I also grew up on DZs collapsing chutes for dragging skydivers in high winds (Pelican Land, Z-Hills, etc.).
                      >
                      > Your intuition that useful power can be extracted from simple parachutes in a collapse-retract cycle is good. We know that both lift and drag make more-or-less equal power with kites (Loyd), and we need lift mostly to get up, then a simple drag cycle can suffice to extract power. This a "Low Complexity" approach, early favored.
                      >
                      > How did you select Vectran as the best torquable fiber? Its not stretchy compared to rubber, so hockling would seem to be a damage risk,
                      >
                      > daveS
                      >
                    • Joe Faust
                      Wow! Thanks for link. Nice set of Barish free-flight kiting systems used for gliding parachutes in the case then in 1965 with those photos.
                      Message 10 of 10 , Jan 29, 2013
                        Wow!   Thanks for link.   Nice set of Barish free-flight kiting systems used for gliding parachutes in the case then in 1965 with those photos. 


                        David Barish         (Just one  r )   Collage from a site http://www.free-flight.org/history.htm     The free-flight kite resistive set is a human in these systems.   Lengthen the lines and format the resistive set to operate with advanced wing behavior, and then use wind differentials while operating control over the upper wing set and the wing-formatted resistive set ... and get into the FFAWE club by adding some rubber-band RATs or just accept the traveling that could be done.   

                        Levopter is continuing news notes on its site.   FFAWE travel from west coast of Africa  to landlocked nations in Africa's interior using Levopters. 


                      Your message has been successfully submitted and would be delivered to recipients shortly.