When conditions are not favourable for their growth (i.e. there is a lack of nutrients) some types of bacteria cells are capable of entering ‘spore’ form. This is a state in which their metabolism is almost entirely shut down and they are no longer technically alive. Spores can remain stable for hundreds of years and (some have speculated thousands of years) and are very robust and they preserve the DNA of the organism in challenging times. However as soon as the conditions are right they are able to convert back to living and viable cells. Spores are interesting to us as architectural designers for two reasons:
1 Spores encompass the idea of a system which is dynamic and responsive to its environmental context – optimised for its energy and nutrient conditions. Something that we often strive to achieve in architecture through the use of dynamic actuated and responsive systems but something which we are unable to do with such elegance.
2 Bacteria sores themselves may also offer the direction for a new architectural technology.
Very recent research has shown that bacteria spores combined with an elastomer like material can be used create very powerful hydromorphic material. Hydromorphic materials can respond to changes in humidity by changing shape. There are a number of hygromorphic materials and most work by combining two layers – which have separate rates of expansion in the presence of moisture. As one layer expands it forces the other layer to change its shape causing the material to bend. In architecture there has been experimentation with timber based hygromorphic materials but, as yet, the bacteria based hygromorphic materials have not been considered by architectural designers.
We have begun to experiment with the basic materials and configurations of Bacilla Spore actuators and, through a Stage 3 (3rd Year Undergraduate) studio begun to work with mechanism that may translate the power the hydromorphic material to mechanisms which may form parts of a dynamic building skin.