A summary report of the Marine Node workshop

Developing concepts and proposals for Space Elevator development

Conducted at the International Space Elevator Conference
23 August 2014

Peter A. Swan
October 2014

=====================================================

Introduction

The preliminary meeting of the ISEC Marine Node team was conducted as a mini-workshop at the 2014 Space Elevator Conference in Seattle.  We had a fantastic discussion on the development of the Marine Node, identifying and exploring multiple topics that are essential for making progress on this key element of a space elevator system.

Marine Node Overview

Dr. Peter Swan, acting as workshop leader, presented the following graphic for the Marine Node.

 The image shows two Marine Nodes, each consisting of a single Floating Operations Platform. The platform in the foreground is shown with a support vessel alongside. The Marine Node may also include an additional Facilities Support Platform. Another key element, the port facilities to support the node, is not shown.

Workshop participants discussed five parameters of proposed locations: ocean currents, sea water status and makeup, sea floor geology and seismology, and weather conditions.  Obviously, these are just some of the parameters of interest.  Attendees also participated in a brainstorming process to develop new concepts and ideas for the Marine Node.

Workshop Goals and Processes

The goal of the mini-workshop was to develop a description of the Marine Node and show how to move towards operations, driving innovations in node design and lowering development risk.

1. Define the Problem.  The questions presented to the workshop participants included these:
   • Where should the Marine Node be located?
   • How many platforms should be provided for each node?
   • What are the characteristics and requirements of the tether connection?
   • What resources are required to meet the throughput goals of the node?
   • What are the security concerns for the node?
   • What businesses can operate at the node?
2. Build on the Marine Node baseline.  Over the last few years, there have been multiple solutions proposed to the problem of how to develop a space elevator Earth anchor, including these:
   • Dr. Edwards' baseline: Single tether, middle of Pacific, oil rig, laser powered
   • IAA baseline: Multiple sites with paired tethers and solar-powered climbers
   • Keith Henson's proposal: Marine nodes 8° south of the equator, angled tethers
   • Japanese proposal: Floating tunnel to island-based surface node, 100 MT tethers
The team looked at these proposals and considered the positive and negative aspects of each to enable progress forward.

3. Make specific proposals.  The following discussion notes are the product that the team developed in the mini-workshop. They comprise three elements:
   • Definition of functional needs to be fulfilled by Marine Node.
   • Presentation of multiple solutions to the needs.
   • Description of the "best" solutions available today or in the future.  This set of descriptions should enable future designers to leverage our comparisons and understand our engineering trades.

Discussion notes

From the teams at separate tables, discussions developed observations, ideas, proposals, and preliminary conclusions in several areas:

1. Loading due to tether
   1. The tether anchor must counteract an upward force of less than 500 tons.
   2. High Stage One provides 25,000 tons of down-force.
   3. For the case of an off-equator tether (4 to 8 degrees south) the tether will be roughly 20 degrees from vertical, leading to significant transverse forces of about 100 tons.
   4. Fuel for marine thrusters required for station keeping at surface node, but not for high stage one
2. The logistics stream from tether base to main base of operations
   1. The team considered ports in Hawaii, South America and Panama
   2. Distance from port:
      1. Locating the platforms 200 miles from a major port is considered practical
      2. A position 1,000 km west of Galapagos would be more difficult to support
   3. Food, fuel are significant components of the consumables requirements
   4. several tugs will be needed
   5. Docking facilities will be required at the platforms
3. Emergency/medical response
   1. For the more distant platform locations, for example 1,000 km west of the Galapagos, only a few helicopters exist with sufficient range to reach major medical facilities.
      1. E.g., the AH-56A, Mi-26, V-22, etc.
   2. Should we rely on Navy carrier groups for medical and evacuation?
   3. Sufficient on-site medical could be developed - it is scalable from existing offshore operations.
4. Moving the platform in case of storm, orbital debris, etc.
   1. It may be necessary to move the tether platform as much as 50 miles.
   2. A 100-ton tug would be sufficient to provide the necessary movement.
   3. How quickly could the base be moved?  Assuming base is moored to sea floor, a few hours to drop moorings and get underway. A 100-ton tug could move the platform at a speed of 2-3 knots.  With integrated submarine propulsion, a speed of 10 knots may be possible.
   4. Movement available at top of High Stage One is 20 - 30 km.
   5. An off-equator platform could be moved by reeling the tether in or out.
5. Seismic loading from sea floor.
   1. There is little seismic activity at nominal location and sea floor depth of 8,000 ft.
6. Additional features and functions
   1. Tether terminus
   2. Tether/FOP Dynamics
   3. Likely new OGVs (Cruise Ships?)
   4. Greater storage capacity (climbers and payloads)
   5. Larger numbers of operations and support personnel
   6. Keep-out zone (safety and security)
   7. Greater movement capability, possibly faster
   8. Larger operations center
   9. More in-depth weather (and ocean) monitoring/sensing
   10. Climber mating equipment
   11. Greater power generation (4 MW for climber)
   12. Power cord handling equipment
   13. Climber refurb facilities
   14. 16 MT per day throughput
   15. 48 MT storage - preparation
   16. 48 MT storage - waiting movement
   17. Climber Repair Modules - storage and preparation
   18. Communications Node

Summary Statement

The mini-workshop defined and discussed many potential problems and solutions for the space elevator Marine Node.  The conference attendees became actively involved in the discussions and ideas flowed freely, achieving progress in the conceptual development of the Marine Node.

Details are very sketchy, but the good folks who ran the previous EUSPEC (European Space Elevator Challenge) have announced a new competition for 2015.  From their webpage:

Details will be posted on the ISEC website and future issues of this eNewsletter as they become available.

Following the 2014 conference an ISEC team decided to undertake a benchmark study of Space Elevator dynamic simulation tools at present in use worldwide.  This study will compare analysis results for one or more test cases and help future researchers get started.

To move forward with this work we are requesting your help.  If you have access to a dynamics simulation tool and are able to contribute your time we will ask you to run one or more simulations using your Space Elevator model and supply us with the results : we are not asking for a copy of your model or software.  In return we will supply you with a report comparing your results with those of other analysts, and of course will acknowledge your help when this report is published in 2015 : detailed results in this report will be made anonymous.

If you are interested in assisting with this project please send an email to peter.robinson@isec.org : we will then supply more details and some questions about your analysis tool.  We hope to be able to supply data for the first model run in early 2015.

The International Space Elevator Consortium (ISEC) is the result of a coming-together of many leading figures and organizations who have worked long and hard over many years to promote the concept of a Space Elevator.  With organizational members in the United States, Europe and Japan and individual members from around the world, ISEC's goal is nothing less than to get a Space Elevator built.

Our Mission Statement says it all:

"ISEC promotes the development, construction and operation of a space elevator as a revolutionary and efficient way to space for all humanity"

Each year we adopt a theme which we use to focus our activities for that year.  For 2009-2010, our theme was Space Debris Mitigation - Space Elevator Survivability.  For 2010-2011 our theme was Research and thought targeted towards the goal of a 30 MYuri tether.  For 2011-2012, our theme was Operating and Maintaining a Space Elevator.  For 2012-2013, our theme was Tether Climbers and for 2013-2014, our theme is Architecture & Roadmaps.

If you agree that building a Space Elevator should be a priority for all of us and you want to help make this happen, please Join Us !  Benefits include eNewsletters (such as this one), the ISEC Journal CLIMB and other items listed on our Join page.

Come and join us and help make the future happen!

The lifeblood of any organization such as ours is the support we receive from our members - and we thank them all.  We especially want to thank our Corporate Sponsors who have contributed funds and resources to ISEC at a higher level.

  

Visit our website at www.isec.org.  There you can join learn more about what is happening in the Space Elevator community and what is being done to advance the concept of a Space Elevator.  Please consider joining ISEC - we foster research and sponsor Space Elevator-related causes, but to do so takes money.  Your contributions are crucial to our success.  Thank you!

If this newsletter has been forwarded to you, you can also sign up to be on our mailing list so you don't miss a thing!