Space Elevator Chris Biedrzycki Ned Cameron Mike Gruener Erick Haro
What is a Carbon Nanotube? Can be thought of as a sheet of graphite (a hexagonal lattice of carbon) rolled into a cylinder.
Why CNTs? • Young's modulus is over 1 Tera Pascal • Strength 100x that of steel at 1/6 the weight (estimated tensile strength is 200 Giga Pascal)
Categories of CNTs • Multi-walled nanotubescharacterized by formation of nanotubes within nanotubes • Single-walled nanotubes
Chemical Vapor Deposition • Involves heating a catalyst material to high temperatures in a tube furnace and flowing hydrocarbon gas through the tube reactor • The materials are grown over the catalyst and are collected when the system is cooled to room temperature • Key parameters are: – Hydrocarbons – Catalysts – Growth Temperature • CVD process involves the dissociation of hydrocarbon molecules catalyzed by the transition metal, and the dissolution and saturation of carbon atoms in the metal nanoparticle • Both MWNT and SWNT can be grown by CVD methods – MWNTs use acetylene gas for the carbon source and a growth temperature between 600 – 800°C – SWNTs use carbon monoxide or methane for a carbon source and a much higher growth temperature (900 –1200°C)
Arc Method • Carbon Atoms are evaporated by a plasma of Helium gas that is ignited by high currents passed through opposing carbon anode and cathode. He Arc-Discharge • Excellent Method for the production of both MWNT and SWNT • CNTs are obtained by controlling growth conditions – Pressure of gas in discharge chamber – Arcing Current on a collector outside the furnace zone
CNT Manufacturers • Carbon Solutions • CarboLex • Carbon Nanotechnologies, Inc. • Fullerene International Corporation • Junye Nano Materials, Co. • Luna Nanomaterials • Luxtera • Nanocs International • Nanoledge • Oxonica • Showa Denka KK • Deal International Inc. • Micro Tech Nano, Inc • Nano Carb Lab(NCL) • NanoLab, Inc • Nanostructured and Amorphous Materials, Inc • Nanosys • Catalytic Materials LLC • INPT
Problems Encountered • Cost – High production costs • Separation – Untangling nanotubes • Length – 63,000 mi is a lot of ribbon
To Infinity and Beyond…. Gigantic antenna – Capable of receiving radio waves from distant sources Large Geosynchronous Station – capable of hundreds of permanent residents, science labs, pharmaceutical factories Settlements on Mars, Moon, Venus
Troubleshooting Cable breakage – unrepairable 2x safety factor If breaks, some will splash down, some will burn up Still create less waste than burning a rocket Nano-epoxy (Nano-tape) – Still in the developmental stages High winds - 155mph winds (Class 5 hurricane) can snap the ribbon position is not in a high wind, or hurricane area Electricity – Is a concern, but chosen location avoids lightning strikes. Oscillations –7-hour natural frequency actively damped by the anchor Radiation – Components are good for 1000 years in orbit Mobility Anchor can move ~1 km each day to avoid debris and satellites Anchor is ~400 mi from all shipping and airplane routes Using current materials? – No.
Entities Involved 3M Corporation Los Alamos National Laboratory Art Anderson Associates Nanoledge Augur Aeronautical Centre NASA - Johnson Space Center Bennett Optical / Compower Owens-Corning Carbon Nanotechnologies Inc. Princeton University Lockheed Martin ReyTech European Space Agency Rutgers University Flight Materials Group U of Mississippi – Space Law Center Foster-Miller, Inc. T. Y. Lin International Harvard University Thomas Jefferson National Laboratory HighLift Systems University of Kentucky
Pricing • Now, Cargo $50,000/lb • Now, Cargo 4,000lb/day • First Elevator, Cargo $100/lb • First Elevator, Cargo 12,000lb/day
Method to Improve Elevator • Use superconducting property of nanotube ribbon • Maglev type ascention