BIS Space Elevator Symposium : 7th November 2017
This 1-day Space Elevator (SE) Symposium was held at the headquarters of the British Interplanetary Society (BIS) at ‘Arthur C Clarke House’ in London, jointly sponsored by BIS and ISEC.
Nine fascinating presentations were made during the course of the day, with all well received by a small but keenly interested audience: in particular the Skype presentations by key ISEC representatives ran smoothly, enabling explanation of key concepts by three greatly experienced SE proponents.
Talks ranged from SE history to technical details of SE concepts, including new work on SE options throughout the solar system. Of particular interest was the news from Adrian Nixon of a breakthrough in graphene production techniques, offering the tempting prospect of a feasible strong material for an Earth Elevator system.
In more detail :
- John Knapman introduced the concept of the Space Elevator, describing the rationale, history, current architecture concepts, physics and challenges. He introduced ISEC, and concluded with ‘Final Thoughts’ from various thinkers.
- Martin Lades (on a day trip from Germany) presented detailed analysis on critical feasibility criteria, with emphasis on climber power, payload and tether interface issues. Tether friction was shown to be as critical as strength, and a significant proportion of early climber payloads could have to be allocated to tether construction and maintenance.
He followed this with a second talk on Mars Elevators, specifically the ‘Omaha Trail’ concept. Unfortunately there was insufficient time to complete this second presentation.
- Mark Haase presented (via Skype) on ‘Advances in High Strength Materials’, describing multiple materials using an Ashby Plot before focusing on descriptions of Carbon Nanotubes (CNT), Graphene and Boron Nitride materials. He concluded that the required 25 MYuri would be achieved in ‘about 20 years’, and would be a CNT-polymer composite. Much further research on cross-linking and polymer interfacing is required.
- Peter Robinson presented described a simple analysis technique that has enabled rapid review of SE feasibility on multiple locations in the Solar System. Of the eight major planets only The Earth and Mars would be feasible, but both require new materials. L1-type elevators could be built on many moons using current materials : an SE on the Earth’s Moon would be at least 80,000km long, so not ideal for technology demonstration. The least challenging location would be on a large asteroid : Vesta was selected as optimum, with a tether 750km long.
- Adrian Nixon outlined his experience and current activity specializing in graphene, and went on to describe the specific material requirements for a strong SE tether material. He explained how current graphene manufacture yielded individual nanoplatelets with little overall strength, and described new techniques for making far stronger continuous graphene sheets using Chemical Vapor Deposition (CVD). He concluded that development of CVD production techniques would yield graphene material of the strength required for the (Earth) SE, describing in-orbit combination and how graphene addresses some anticipated SE operational issues.
- ISEC President Pete Swan presented (via Skype) on the ‘Galactic Harbour : Half Way to Anywhere’. He described current Space Elevator concepts, history and lexicon, followed by a description of past and current IAA and ISEC studies. He described the potential future activities at and around the Earth Port, GEO Node and Apex Anchor locations, and concluded with his Unifying Vision of Space Elevators as a Galactic Harbour.
- Ian Woolard presented his concept for Safe Space Fountains for low cost orbital launch. He outlined a dynamic structure that could be built using existing materials, arguing that a smaller system (80km high) could avoid the safety and cost concerns surrounding other Launch Loop proposals. He explained that dynamic analysis had addressed stability concerns, and estimated that a launch cost of GBP 160/kg to LEO could be achieved. Funding is required to enable small-scale demonstration.
- David Raitt presented (via Skype) on a ‘Short History of Space Elevators’. He described the detailed rationale, history and pioneers of the SE concept, followed by examples of literature and artwork. He then covered the scientific work from the 1990s onwards, detailing various conferences, sessions and competitions. He described press and on-line publications over the last 20 years, and concluded by confirming that ‘Tomorrow Never Comes … The future is the History of Tomorrow’!
- John Knapman closed the Symposium by describing the current state of Space Elevator research. He described material research status, climber design & power concepts, hazards & maintenance, and the ‘High Stage One’ and ‘Multi-Stage’ Elevator concepts. He then outlined the current ISEC project on building a simulation package to model dynamics, electrodynamics and radiation behavior. He concluded by outlining the recent JBIS publication and described the research work in progress by ISEC, in Japan and in China.
Thanks must be given to BIS for their friendly and faultless hosting of the event at their small and intimate venue, with seamless technical support … and of course excellent catering!
This summary presents only an outline of the presentations, and may omit or misrepresent some of the work. PDF copies of all papers (except #7) will be available from BIS or ISEC in due course.
Peter Robinson November 2017