Page 67 - Build 165

industry started using CNC technology for precise cutting of complex components. This digital manufacturing technique involved several technologies such as water jets, plasma arcs and laser beams to cut sheets of material.
Leap forward with multi-axis milling
In the 1970s, multi-axis milling enabled the next giant leap in digital manufacturing. It was first used in the UK where it was employed to remove solid parts directly from a material and to form a uni ed 3D shape.
This method attracted large architectural rms in the US, who used it to produce archi- tectural models and construction prototypes. The automatic milling machines that could handle stones and columns lead to subtractive methods (the cutting away of material) that found their way to manufacturing construc- tion components in the late 1980s and 1990s.
More recent attempts have employed subtractive methods to off-site or on-site manufacturing elements with an intricate geometric design. This may involve producing formwork for casting double-curved concrete components or for fabricating laminated glass panels with complex curvilinear surfaces.
Next step – additive digital fabrication
In the 1980s when the subtractive platforms were dominant in digital fabrication, addi- tive digital methods began emerging. In contrast to subtractive manufacturing, the additive digital fabrication builds up the solid body incrementally by adding material layer by layer.
Emergence of 3D printing
While the first 3D printing system that implemented additive digital fabrication was commercialised in 1988, it took until the 2000s for the new method to ourish.
The notion of additive digital fabrication has enabled direct translation of visual concepts into reality. It has mainly been materialised in fabrication laboratories, where computer-simulated models are converted into physical equivalents.
In construction, there has been increasing attention on the architectural, ecological and structural performance of 3D printing tech- nology. Its adoption, however, has remained limited to producing components such as steel elements of lightweight structures. Impediments to large-scale production
The limited size of the products, expensive equipment required and lengthy produc- tion time have been the main impediments holding the building industry back from large-scale production. In an attempt to address these issues, the large components are manufactured in smaller segments o site and erected according to a 3D digital model on site.
Alternatively, companies such as Contour Crafting in the US, WinSun in China, WASP in Italy and MX3D in the Netherlands are developing additive manufacturing tools and techniques that can handle one-to-one digital construction.
WinSun has reported construction projects developed with the use of a mega 3D concrete printer on site.
Shift to on-site robotics
There has been a recent shift to develop methods for on-site robotic construction. Researchers are exploring the application and implications of robotics to architectural design, building fabrication, assembly and construction.
This includes employing robotic arms in modular construction, cable beams in erecting tensile structures, fabricating timber
structures and for tiling. Developments also involve custom computational design and simulation frameworks capable of operating robotic machinery in uncertain outdoor environments.
The robotic devices are moving and xing heavy steel beams, pouring concrete, painting and spraying insulation. In a new experiment, Dutch company MX3D entirely constructed a steel bridge in Amsterdam using robots.
Integration of digital fabrication with BIM
Digital fabrication, which was initially developed for educational purposes, is progressively evolving into a fully edged industry and growing quickly to enhance the speed, precision and cost-e ectiveness of construction.
With the emergence of building infor- mation modelling (BIM) and governments requiring its mandatory application, the true advantages of digital fabrication are self-evident. Integration and harmonisation of digital fabrication with BIM are projected to transform the construction industry.
Augmented reality’s role
The next technological wave likely to change the construction industry is associated with fast-growing augmented reality technology, which can help maximise the accuracy of installations and reduce confusion in interpreting orders.
While there are undoubtedly many chal- lenges along the path to smarti cation, the architecture, engineering and construction industry in New Zealand should become increasingly intertwined with the emerging digital fabrication trends and the techno- logical solutions discussed here.
The future is now
Build 165 — April/May 2018 — 65
FEATURE SECTION