Cluster 1: Sommerville – multiple part types

Based on the Sommerville tetrahedron, part systems using multiple compatible types can be created that produce more differentiated complex aggregations.

Larger scale part


To expand the catalog of parts based on type-18 clusters from a previous study a larger-scale part can be created by merging four halves of tetra-cells into a new part, that contains a flat cluster of four bike frames. The new part C has four connections at the same locations as in the initial parts A and B and is therefore compatible with the base parts – aggregations using this set of 3 part types are interconnected.

Aggregations contain larger voids and have a certain directionality. This differentiation and deviation from the repetitive patterns of single-part type systems seem to offer potential for architectural scenarios.

Smaller scale part

Additional compatible parts can also be found when subdividing the base cell (Sommerville tetrahedron).

The additional parts each have at least one connection compatible with the part it is a subdivision of, but each also introduces new connections. When organizing the rule set to allow only connections in between compatible connection types, the overall system still can close onto itself – that is to interconnect at standard connections. With this specific cluster geometry inside the tetra cell, additional bike frames can be added to part A to match some of the connections introduced by the smaller parts.

Often such discrete aggregation systems either offer interconnectivity at the “cost” of design limitations because parts have to be constrained to populate a regular grid (network graph) for interconnections to occur; Or when part systems are designed freely in a bottom-up process, the resulting aggregations are usually highly irregular L-systems with only loose ends.
The system described here shows the potential to combine the advantages of both types of systems – highly complex aggregations can be achieved that can vary from repetitive to irregular patterns by maintaining the capacity to interconnect.