Responsive materials react and evolve relative to their environments. At an architectural scale they work as a distributed system across the architectural surface to negotiate internal and external inputs. This research looks at creating new materials with rubber as their base that exhibit responsive and emergent behaviors. Traditionally rubber has taken a secondary role in architectural tectonics, relegated to assisting other materials in performing their tasks: structural dampening, surface finish and weather proofing to name a few. This research looks at developing constructions made from urethane rubbers of different shore hardness that exhibit variable properties across their surfaces. This has led to the design of customizable components whose behaviors can be altered by shifting the ratio of hard to soft rubber in them. Because subtle changes in each component have a profound effect on the overall performance of the structure we have simulated the components in scripted environments to study the emergent behaviors that result from their iterative combinations.

Rubber’s elasticity and polymorphism makes it difficult to accurately judge its performative qualities. It’s only through empirical analysis that the material’s compressive and tensile tolerances can be gauged. With rubber composites, this is further complicated by their different shore hardness and multiple shaping and patterns. In addition, rubber’s prohibitively high weight to volume ratio requires proper calibration of material thickness and adhesion of parts so that it can exhibit predictable qualities. The task of creating effective prototypes can be likened to cooking where not only the recipe but the manner in which the ingredients come together is extremely crucial.

To fabricate a composite urethane elastomer a sequential pouring of hard and soft rubbers is needed. This requires a reconfigurable mold (RCM) that can change its shape for each discrete pour without adversely disturbing the previous one. We have developed two types of RCMs one that works with additive templates and another that creates cavities through movable rods. The first has been used to create panels of 3/4”x1’x2’ while the second has produced rods of 2”x2”x2’. In addition to facilitate pouring and adhesion between parts RCMs are useful heuristic devices. Their dynamic quality allows one to explore variation on a type without having to construct unique molds for each pour. This has allowed us to contemplate their possibility for mass customization as we experiment with all the useful recipes that the RCMs can accommodate.

Variable materials offer another challenge when it comes to the repetitive combination of different parts. The performance of the individual component does not necessarily predict the collective performance of the many. Here we are faced with a daunting complexity whose emergent qualities can only be fully apprehended by the actual construction. However, by folding this line of inquiry into digital models and scripted environments we have been using relational geometries and parametric modeling to begin to understand the emergent performance of the many. These simulations are also useful heuristic devices as they preempt possibilities that may not have particularly useful or interesting emergent qualities.