Projekti:Nano-to-Meter-Scale Building

In summary
Nano-to-Meter-Scale Building (nanoBuilding) is a multidisciplinary research project with the long term goal to develop a new way of building, which unfolds from nano into meter scale. The nanoBuilding concept is based on bionanorobots, producing carbon nanotube based building materials using CO2 from the air.

Motivation
Development of the core nano and biotechnology is leading to results that are extremely interesting for production of the buildings on the nano level, thus growing buildings on site from the nano into the meter range. Although areas like nanorobotics, DNA nanotechnology, molecular nanotechnology, programmable materials, and programmable cells are still considered to be speculative to some extent, their fast development encouraged us to start systematic research of new ways for modeling and construction of buildings using bio-nano-technologies. The main motivation, however, was the recognition that, if designed in a sustainable way, the new ways of nano-to-meter-scale building (nanoBuilding) could significantly reduce the many negative impacts of traditional construction and operation of buildings on the environment (production of cement and other building materials, waste, resource transportation, and energy consumption and pollution during construction and operation). And even more. By using Carbon from CO2 from the air it would literally clean the air.

Our motivation to begin with conceptual top-down design of a nanoBuilding system before nanotechnology delivers the necessary basic technologies was to speed-up the process by formulating the requirements and thus encourage researchers in bio and nanotechnology to direct their bottom-up research towards them and in this way help the construction industry to reach that ultimate goal, a fully automated nano-to-meter-scale building. With the interdisciplinary top-down and bottom-up research we want to construct testbeds in which we will be able to study the concepts of nanoBuilding and develop technologies that will enable automated building from nano to meter scale

The concept of building from nano-to-meter-scale
During discussions and study of the nano-to-meter-scale building concept two different approaches have emerged. The basic difference is in the way of controlling the building process. One is a more typical engineering, mechanicistic approach with extrinsic constrol and instruction passing, the other is using intrinsic programming of bionanorobots. The Extrinsic Programming Approach is presented here as it seems to be closer at reach.

A top-down concept has been developed following certain suppositions, which are closely related to our motivation to reduce waste, pollution and energy consumption caused by traditional building technologies. The first supposition therefore was to use materials that exists on-site and can be transformed into building materials at the nano level. As already explicated in the previous section carbon nano tubes have extraordinary characteristics, which can be varied using todays production nanotechnologies. The next supposition therefore was to use Carbon as the basic material. As Carbon exists in nature in vast amounts the next supposition was to extracted it from CO2 from the air. The building process is to be executed on the nano level using active nano devices that shall be controlled extrinsically using a detailed Building information model (BIM) as the source of all necessary information. The defined suppositions brought us to the following conceptual solution:
 * 1) The fundamental building process is taking part at nano level by multifunctional nano devices (nanorobots), which are capable of
 * 2) * capturing CO2 from the air and extracting C molecules from it, releasing O2 back to the air, and
 * 3) * building 3D carbon nanotube arrays with characteristics required for a specific area (strength, conductivity, colour, transparency etc.), NanoSlice_projection_2D.png
 * 4) Nanorobots are controlled and powered externally by light; instructions are coded using specific wavelengths.
 * 5) Light is emitted by a projector installed above the site; to avoid interferences with light emitted by other sources, adequate wavelength spectrum has to be chosen.
 * 6) The projector is using the detailed BIM model as input, and transmits continuously the horizontal crossection, going from the bottom to the top height of the model
 * 7) Openings of the final model are temporarily filled with carbon nanomaterial, which transforms back into CO2 after specific time period (or under specific conditions), fullfiling its function as a supporting structure.
 * 8) All utilities and coatings (if necessary) are built at the same time, together with the bearing structure (e.g. pipelines, power lines, communication lines), and are part of the building.

The building process consists of the following steps:
 * 1) Designing a detailed BIM model with all necessary utilities and coatings, as well as temporary fillings (these can be added automatically after the building model is finished, by following the rule that every part of the structure has to be vertically supported down to the base level)
 * 2) Site preparation (excavation, projector installation)
 * 3) Deploying nanorobots onto the maximal extents of the building layout NanoBuilding.png
 * 4) Starting the proces by continuously emitting instructions (represented as specific light wavelengths) to build 3D CNT array with required characteristics, until the top of the building is reached.
 * 5) After the light is off for a certain time, the nanorobots stop to function permanently, thus preventing of any unwanted activity after the process is finished.

The load bearing material is in function instantly, therefore the temporary supporting material can dissolve after the building is finished. It dissaperas off the building in form of CO2 gas (e.g. from rooms, niches, pipelines and any other holes). With this the building is finished. With transparent CNT even windows could be "built-in" during the process, as well as some further equipment. It is, however, to early to explore in such detail all the effects of nanoBuilding.

The Building material
As we have already seen above, Carbon nano tubes with various characteristics have been designed and produced. Following characteristics are required for the proposed nano to meter scale building process:
 * bearing strength (for bearing of loads)
 * conductivity (for electrical power and communication installations)
 * chemical resistance (for coatings and pipes)
 * colour (for coatings)
 * transparency (for lighting)
 * Self-decomposition (for decomposition of supporting structures.

Carbon nanotubes posses many of the properties one would choose in designing an ideal structural material. They have a very high strength to weight ratio, are stable and inert at a wide range of temperatures, and can have varying degrees of conductivity based on their geometric properties. However one challenge in utilizing carbon nanotubes in meter-scale building is finding a natural configuration of nanotubes that allows for unlimited assembly in all three spacial dimensions while retaining the afore mentioned properties. One very promising family of configurations can be found in Schwarzite structures, name so in honor of mathematician H. A. Schwarz who first explored similar triply periodic minimal surfaces.

Schwarzite structures are a class of fullerenes that exhibit negative Gaussian curvature. They are produced by the insertion of heptagonal and octagonal rings into the graphene lattice otherwise containing only hexagons. It is these lattice deformities that create the negative curvature necessary to create a structure that has symmetries in three spacial dimensions. In contrast spherical fullerenes such as C60 contain pentagon rings that produce a positive curvature leading to a closed structure. The spacial symmetries of Schwarzite structures fulfill the necessary requirement of unlimited assembly in three dimension. In addition Schwarzite structures are stiff and can be either conductive or insulating depending on their topology. The figure on the side shows a possible nanotube configuration to be used as a nano-scale building block. The tube junctions are Schwarzite structures that have been connected by single wall carbon nanotubes of similar diameter.

Present project team

 * Danijel Rebolj, University of Maribor, Construction informatics Center, Top-down concept, coordination
 * Martin Fischer, Stanford University, Center for Integrated Facility Engineering, Impacts on design and construction
 * Drew Endy, Stanford University, Synthetical Biology Lab, Biological technologies
 * Thomas Moore, Michigan State University, Nanorobotic System Lab, Nanomaterials
 * Aleš Mrkela, University of Maribor, Construction informatics Center