June 24, 2008

Space elevator games and Lunar lander contest 2008 preview

The Space elevator power beaming (climber) competition is on Sept 27, 2008

Vertical Distance: 1 kilometer (ten times the 2007 distance)
Speed for prizes: 2 m/s for $900,000 and 5 m/s for $2 million

11 teams have entered the 2008 power beaming / climbing contest

The University of Saskatchewan space design team
The University of Saskatchwan team almost won in 2007
University of Alberta racing team
Queen's space elevator team
McGill Space elevator team

Kansas City Space Pirates
MClimber from Michigan
NSS Space elevator team
Laser Motive
TXL group

Team Nippon
Earth track controllers

Proving Space Elevator components by 2010
The Space Elevator requires two major achievements: a tether which is at least 30 GPa-cc/g strong (see below), and a long-range power beaming system in the Mega-Watt range.
The Spaceward foundation plan to demonstrate by the year 2010, a 10 GPa-cc/g CNT tether, and a multi-kWatt km-scale power beaming demonstration.

With these benchmarks demonstrated, the Spaceward Foundation plans to pursue a 5-year development phase (phase 1) of full-performance components, followed by a 5-year system development effort (phase 2). This puts the beginning of construction (phase 3) around the year 2020.

Tether strength to weight ratio seems to be on track to reach the necessary levels by 2013.

In 2007, 9 GPa g/cc strenth material for millimeter lengths

"High-Performance Carbon Nanotube Fiber", Krzysztof Koziolet al, Science Magazine, 2007 - Measurement of the strongest of a sample of mm-long pure aggregated carbon nanotube fibers.

In 2008, 40 GPa g/cc
from Sparse (Carbon nanotubes) CNT Composite

"The extraordinary reinforcing efficiency of single-walled carbon nanotubes in oriented poly(vinyl alcohol) tapes", Wang et al. IOP Nanotechnology vol. 18 –
inferred strength of SWNTs from a 1% CNT reinforced plastic tape.

Abstract. This paper reports on oriented poly(vinyl alcohol)/single-walled carbon nanotube (PVA/SWNT) tapes that were prepared by a mild processing route, involving the use of dimethyl sulfoxide (DMSO) as a solvent. Composite films with homogeneously dispersed SWNTs were cast from solution and drawn into oriented tapes using solid-state drawing. The obtained tapes showed the extraordinary reinforcing effects of the SWNTs, as the addition of 1.0 wt% SWNTs tripled the tensile strength of the PVA tapes. Micromechanical analysis showed that the nanotube contribution to the composite strength was as high as 88 GPa, which is very high when compared to other data reported in the literature, and for the first time begins to exploit the theoretical strength of nanotubes.

Goal 2010, 35 GPa g/cc for 1000 km x mm

Minimal value for Space Elevator ribbon, Taper Ratio=6.3 with 33% safety factor.
Comparative Ribbon Mass = 4.6 - May require more efficient power system.

Goal 2011, 50 GPa g/cc for 1000 km x mm

Basic value for Space Elevator ribbon, Taper Ratio=3.5 with 33% safety factor.
Comparative Ribbon Mass = 2.0

Goal 2012, 80 GPa g/cc for 1000 km x mm

Desirable value for Space Elevator ribbon, Taper Ratio=2.5 with 50% safety factor.
Comparative Ribbon Mass = 1.0

The 2008 work by Z Wang is getting a follow up navy study for increased percentages of carbon nanotubes in plastic

This STTR requests proposals that develop a clear scientific understanding of the main obstacles to ultrahigh CNT loading in nanocomposites and that proposes new methods or approaches to increasing the loading of well dispersed CNTs in structural resins beyond 10% weight fraction.

The Lunar Lander contest is October 24-25, 2008
There was almost a winner in 2007 and 2006. There should be a winner in 2008.

Space Elevator conference Friday, July 18 thru Sunday, July 20 in Redmond Washington

2nd European climber workshop - Luxembourg - October 18 thru October 19. 2008

1st Japanese space elevator conference Nov 2008

Wikipedia on the space elevator