HexDome 

Hexagonal Geodesic Domes - Simulator

Springie

Note: a vastly improved distant descendant of this program is now available from http://springie.com/.

Tensegrity Simulator

To assist visualising the type of dome under discussion on this web site, we've written a simulator, capable of rendering multi-layer geodesic domes:


Tensegrity Simulator

The program simulates the physics of mass-compression-tension structures - and allows them to be mainpulated interactively in real time from within a browser window.

A number of structures are available to view - including some "hexagonal" domes - and some conventional geodesic structures.

These can be distorted and smashed up - a process which gives some idea of the stability of the structures.

System requirements

This is a Java program. It needs Java 1.1 or better.

The program also appreciates high resolution displays - so please open your browser window as big as you can.

Dome viewer

Use one of the following links to run the program:

Run applet(Java applet)(Native JVM)(158K)
Run applet(Java applet)(Plugin JVM)(158K)
Download(Jar file)(Jar)(158K)

Brief instructions

Click with the left button to select nodes - and drag them around.

Click with the right button to delete nodes.

Editing system

The dome simulator seen here is part of a much more complex and sophisticated dome construction and editing system.

I recommend users try the viewer before trying the editor.

The system allows domes to be "grown". This operation proceeds by dynamically inflating large balloons until they touch each other - and then allowing them to apply pressure to their neighbours. The balloons are then deflated - and form the nodes of the resulting structure.

This process naturally allows construction of irregular domes - as well as regular ones.

You can try the editor using the links below:

Run applet(Java applet)(Native JVM)(158K)
Run applet(Java applet)(Plugin JVM)(158K)
Download(Jar file)(Jar)(158K)

Unfortunately, while some elements are self-explanatory, there are not any instructions for the editor at this stage.

Aims

A physics simulation seems needed to address some currently-unresolved questions about these sorts of domes.

As a brief summary:

  • Optimal shape

      In theory, the hexagonal structural framework of these domes should be self-supporting (though unstable) - and the stabilising framework should not need to perform any real work - unless the structure is perturbed.

      However - the shape of the dome and the length of the struts has to be exactly correct for this situation to arise.

  • Gravitational stress

      Many domes exist in strong gravitational fields - and the resulting forces may affect the geometry and design of the dome - by concentrating structural materials in the lower, weight-bearing regions of the dome. Simulation should help throw light on this issue.

  • Material properties

      Lastly, I hope such simulations will be capable of a certain degree of stress- testing, give some clues about the required properties of the materials involved in constructing physical domes.

Source code

Source code is available here.

License

This page - and the program it describes - has been placed in the public domain by its author.


Tim Tyler | Contact | http://hexdome.com/