Showing posts with label automation. Show all posts
Showing posts with label automation. Show all posts

Friday 10 November 2023

Reorganizing Construction with 3D Printing

 Combining Offsite, Onsite And Nearsite Manufacturing In Construction  

  


 

The current mix of onsite construction and offsite manufacturing has become a well-

developed and efficient system of production, but the level of efficiency and productivity achievable is limited by the lack of significant economies of scale in a project-based industry. With 3D printing and digital fabrication this is no longer the case, and a new off/on/nearsite production mix that combines offsite mass production with onsite and nearsite manufacturing is possible. This introduces a new option in the organization of construction.

 

Can the industry greatly increase the share of components manufactured onsite or nearby, and do so while reducing embodied carbon and increasing choice and quality for clients? Could a significant share of components be manufactured onsite or nearby, using automated machinery to provide just-in-time delivery of structural elements as well as fixtures and fittings?

 

 

The Current System Combines Onsite Work and Offsite Manufacturing

 

Onsite construction is a project-based activity to deliver a specific building or structure in a specific location. It is a dense, highly regulated network of industries, utilising standardized materials and components to deliver buildings and structures using well understood processes. The system may not be elegant, but it is flexible, sophisticated and resilient, and coordinates many firms in a widely distributed value chain. Because this is an efficient system, any new technology will have to perform extremely well to have any significant effect on an industry as large and diverse as construction.

 

Mass production of standardized products justifies the capital investment in plant required for products where market demand is well known and stable, unlike the highly variable demand for buildings which rises and falls with the business cycle. However, while there are factory made structures and components, the number of standard buildings is limited and onsite production is organized around standard parts and materials. Manufacturing, in contrast, is organized around standardized products and continuous production runs. 

 

The current system is therefore an efficient mix of onsite work and offsite production of prefabricated and manufactured components, with the combination varying depending on the type of project and location. The alternative that has been attempted many times with varying degrees of success is to replace onsite work with assemblies like panels, pods and modules that are manufactured offsite. However, the economies of scale of offsite manufacturing (OSM) are counterbalanced by the significant capital and transport costs involved, and OSM is not yet a viable alternative for many projects, at a time when improving the productivity of construction is a crucial element in addressing current issues in delivering housing and the energy transition. 

 

Is there another alternative to OSM? What would a different way of organizing construction look like? What would be the effect of increasing the amount of work done onsite by manufacturing more, or most, of the structure and components on or around the construction site? How can that be done? 

 

 

Onsite and Nearsite Manufacturing with Digital Fabrication

 

Over the last decade digital tools such as building information modelling (BIM), digital twins and design for manufacture and assembly (DfMA) have become widely, although not universally, used in construction. While these have been applied to OSM, they have not solved the fundamental problems of limited economies of scale and large capital requirements. However, instead of reducing the amount of onsite work, these tools can be used to produce many of the components of a building anywhere, using new production technologies based on digital fabrication. 

 

Digital fabrication turns design information into physical products using automated processes, providing the cutters, printers, millers, moulders, scanners and computers needed for designing, producing and reproducing objects. The tools include traditional subtractive ones for cutting, grinding or milling, but the focus has been on research into new methods of additive manufacturing using different methods of layering materials using 3D printers. The information needed to create a 3D blueprint is generated during design, and it is a relatively small step to move from a digital model to instructions for a 3D printer. Printing of metal, ceramic and plastic objects from online design databases in fabrication laboratories (fabs) has found industrial applications.

 

There are three methods for 3D printing: stereolithography, patented in 1986: fused deposition modelling, patented in 1989: and selective laser sintering, patented in 1992. It didn’t take long before research into 3D concrete printing (3DCP) began, focused on developing the equipment needed and the performance of the materials used. By 2022 the commercialisation of 3DCP was underway, with two types of systems available. One using a robotic arm to move the print head over a small area, intended to produce structural elements and precast components, the other a gantry system for printing large components, walls and structures. In November 2023 the Additive Manufacturing Marketplace has 44 concrete printing machines listed, ranging from desktop printers to large track mounted gantry systems that can print three or four story buildings.

 

Figure 1. Concrete printers

 


Clockwise from top left: COBODCybeLuytenKampBlack Buffalo

 

Once a BIM model of a project has been created it can be used to provide instructions for production of both the structural elements and other components of a building. When a concrete printer is used to build the walls it is an example of onsite production, but 3DCP can be used to make stairs, columns or other elements onsite as well. Producing components onsite from bags of mixture avoids the cost of handling and transport, and for large items avoids the load limits on roads and trucks. However, site space and access is often restricted, so setting up a fab nearby would still take advantage of the lower transport costs of bulk materials and a shorter distance for delivery while maintaining control over the production process. That is nearsite production. Local suppliers offering manufacturing on demand with print farms (factories with many machines) and many different printers that can produce large runs and specialised components is a nearsite form of production rather than OSM

 

The potential of 3D printing in construction is not limited to concrete. The Additive Manufacturing Marketplace had 1,852 printers listed, and many of those printers could be used to produce fixtures and fittings for buildings. Suppliers offering manufacturing on demand with print farms for local production of building components might include the established manufacturers with specialized fabs producing metal, plastic and ceramic finishes, fixtures and fittings. A modular fab in a container customised for construction, or even a specific construction project, can be set up onsite to produce components as the schedule requires. Larger sites might need a fleet of fabs. Restorations and repairs can be done with replacement parts made onsite from scans of the original.

 

This does not suggest the end of mass production of all standardized components, economies of scale are the economic equivalent of gravity, but onsite and nearsite manufacturing using digital fabrication does not have to achieve the same economies of scale needed for mass production. The price of a mass-produced item includes its packing, storage, transport and delivery, costs that local just-in-time production avoids while providing more control over the supply chain. Then there are the potential economies of scope from integrated design-production-installation processes, which could be provided through platforms developed by companies like PT Blink and Project Frog, or the UK Product Platform

 

The view here is that, over the next decades, the diffusion and spread of new production technologies will deeply affect how construction delivers buildings and structures. The options available between onsite, nearsite and offsite production will broaden considerably as 3D printing and digital fabrication capabilities increase, and the choice will be determined by the economies of scale and installed cost of local versus offsite manufacturing. The tradeoff between the cost, time and quality of the current onsite/offsite production mix and a new off/on/nearsite production mix will vary greatly across locations and projects, so this new way of organizing construction will coexist with the current system for many decades to come. 

 

Figure 2. Print farms

 


Clockwise from top left: Zortrax3D SystemsDesign 3D PrintFormlabsOptomec

 

The combining of robotic and automated machinery with 3D printing of parts will open up further possibilities. Site processes can be structured around components and modules designed to be assembled in a particular way, and machines to assemble those components and modules can be fabricated for that purpose. The FBR bricklaying machine below is an example of this, designed to use custom made blocks larger than conventional bricks. Another is the RoBIM robot making wall panels from prefabricated components. 

 

Designing an automated production process that includes the machines and equipment needed to move and install parts produced by printers and robots puts digital fabrication at the core of an integrated system of design, manufacturing and assembly. This can work as well in construction as in any other industry. 

 

Figure 3. Construction automation

 


From left: RoBIM wall panel robot, Hilti Jaibot for M&E fixing, ABB robot team, FBR bricklayer

 

Production technologies based on digital twins link localised digital fabrication with online design databases and, as well as concrete, materials like steel, ceramic and plastic can be used to make components and fittings. The robotic and automated machinery and equipment being developed for construction is also based on digital twins, as are the various types of drones used to layout and monitor construction sites. 

 

 

Combining Offsite, Onsite and Nearsite Production 

 

The combination of digital twins and digital fabrication will be transformational if it significantly alters existing economies of scale in the industry. Digital fabrication is a technology whose use has a high probability of becoming ubiquitous as the cost of fabs falls and the supply chain of raw materials continues to develop. Advances in automation and mechanization have the potential to significantly increase onsite and nearsite production in construction, using 3D printers to make and finish both structural elements and a wide range of fixtures and fittings.

 

This introduces a new option in the organization of production for delivery of buildings and structures. The current choice between onsite work and offsite manufacturing is a well-developed and efficient system, but the level of efficiency and productivity achievable is limited by the lack of significant economies of scale in a project-based industry. With digital fabrication this is no longer the case, and a new production mix that combines onsite and nearsite manufacturing with onsite construction work is now possible. 

 




Wednesday 3 March 2021

The digital construction production system

Where is the technological frontier in Construction?

 

 

The fourth industrial revolution has already affected the construction industry through demand for structures for renewable energy and buildings like data centres, warehouses, ‘dark’ kitchens and supermarkets for online delivery services. Some of these buildings and structures already use forms of applied AI in their management and operation.

 

The construction industry is wide and diverse, and the various parts of the digital construction production system are in various stages of development. Over time the development of AI and associated digital fabrication and production technologies will reshape the existing industryled by fundamental changes in demand (the function, type and number of buildings), design (the opportunities new materials offer), and delivery (through project management). However, these developments are  

 

Automation technology is at the point where intelligent machines are moving from operating comfortably in controlled environments, in manufacturing or social media, to unpredictable environments, like driving a car or truck. In many cases, like remotely controlled and autonomous trucks and trains on mining sites, the operations are run as a partnership between humans and machines, or as Brynjolfsson and McAfee put it “running with the machines not against them”. These innovations might reasonably be expected to affect site processes and project organization, as concrete and steam power did in the past. Table 1 has examples of where the technological frontier was in 2020 for plant and equipment and construction materials, as an indication of the range and extent of this wave of innovations. Missing from these lists is smart contracts using blockchain. 

 

Invention and innovation based around BIM, digital twins, digital fabrication and advanced manufacturing technology is starting to fundamentally affect the construction production system through economies of scale. Over time this will alter the balance between on-site and off-site production of building modules and components, and how they are handled, assembled and integrated. Because there are many different types of building in many places, production methods vary widely across the industry, so the use of these new materials and technologies will be varied. 

 

Transport costs have always been important, but the option of site production has been limited due to standardization of mass produced components. The combination of BIM, online design databases and digital fabrication allows on-site production of some building components. Combining robotic and automated machinery with digital fabrication and standardized parts opens up many possibilities. 

 

Past technological changes in construction operated over the three dimensions of industrialization of production, mechanization of work, and organization of projects. Automation and AI can also be expected to work along these dimensions as the fourth industrial revolution reconfigures them by linking data through the life of a project. The role of AI enhanced cloud-based platforms that integrate design, production and delivery of components and materials with digital production technologies that allow mass customisation will be significant in the production of components and materials.

 

Table 1. Examples of the construction technological frontier in 2020

Plant and equipment

New materials

Autodesk BUILD Space – Boston

UK construction manufacturing hub

Exoskeletons – Esko, HULK

Remote control equipment – CAT, Komatsu

Drone monitoring – Skycatch, Icon, Vinci

Smart helmets –  Trimble Hololens, Daqri

Platforms – Katerra Apollo, Project Frog

Build autonomous skidsteer

FBR Robotics ‘Wall as a service’ 

Otis ‘Elevator as a service’

Sensor fitted cranes

Automated engineered wood factories

3D concrete printing with boom system – ICON, Aris, 3D Constructor

3D concrete printing with gantry suspended nozzle – D-Shape, BIG, US Marines

Onsite metal printing – GE, MX3D, Aurora 

3D printing of combined steel and concrete

Roller press printing of smart fabrics 

4D printing of shape memory materials 

Molecular engineering of materials  

Improved concrete additives and sealants

Components with cloud-linked sensors

Cloud-based fixtures and fittings

 

Source: Company and industry reports.

 

For mechanization, the characteristic changeability of construction sites is challenging for automated and robotic systems, and it might take decades of investment for machines able to do site work or for humanoid robots to do human tasks. In some case a human supervisor operating a team of robots or several pieces of equipment, each with limited autonomy, might work better. A worker with a smart helmet could monitor these machines both on the project and in the site model. Beyond site preparation however, there may not be many tasks left if site processes are restructured around components and modules that are designed to be assembled in a particular way, and machines to assemble those components and modules can be fabricated for that purpose. For an industry with an aging workforce there is the potential of exoskeletons for site work, a form of human augmentation that combines human skill with machine strength.

 

For organization of projects digital platforms providing building design, component and module specification, fabrication, logistics and delivery can be expected to become widely used. Platforms provide outsourced business processes, usually cheaply because they are standardized, and are available to large and small firms. Also, platforms use forms of AI to monitor and manage the data they produce, the function of intelligent machines. Examples are Linkedin (matching jobs and people), Skype (simultaneous translation of video calls), AWS and other cloud-computing providers, and marketing, legal and accounting software systems. Cheap, outsourced, cloud-based business processes can lower fixed costs and thus firm size, because firms can focus on their core competency and purchases services as necessary as they scale, leading to more entry and more innovation. If these digitised business processes are cost-effective and become widely used, they can provide much of the data needed to train machines as project information managers.

 

The BIM model of the project links the design and fabrication stages to the site and the project[i]. Digital fabrication produces components and modules designed to be integrated with on-site preparatory work and assembled to meet strict tolerances. Project management would be more focused on information management, and the primary role of a construction contractor might evolve into managing a new combination of site preparation work and integration of the building or structure with components and modules, some of which may be produced on-site in a Fab if economies of scale permit. 

 

In this case, the industry would, perhaps slowly, reorganise around firms that best manage on-site and off-site integration of digitally fabricated parts. With outsourced business processes and standardized site and structural work, that would be a key competitive advantage of a construction firm. Firms would become more vertically integrated if they become fabricators as well, reinventing a business model from the past when large general contractors often had their own carpentry workshops, brick pits or glass works and so on.    

 

While firms involved in construction of the built environment are facing technological advances that will affect many aspects of the technological system, this is a process that happens over years and decades. It takes 30 to 50 years between invention of a major new technology like cars or computers and its use becoming widespread, examples are discovering the double-helix and biotechnology, the dynamo and electricity, and the first electronic computers in the 1940s. 

 

How long a transition to a new production system largely built on automation and digital fabrication coordinated by AI takes might take is unknown. While machines can replicate individual tasks, integrating different capabilities and getting everything to work together is another matter. Combining a range of technologies is needed for workplace automation, but solving problems involves specific technical and organizational challenges, and once the technical feasibility has been resolved and the technologies become commercially available it can take many years before they are adopted. 

 

This suggests there will be many new roles emerging in construction over coming years, for project information managers, BIM supervisors, integration specialists and other fourth industrial revolution workers. Because these jobs will be primarily on new projects, they will not quickly replace the many existing jobs in the industry that maintain the built environment. 

 

Nevertheless, the technological frontier is moving again, and new construction projects will generally utilise the most cost-effective technology. Current AI technology provides services such as GPS navigation and trip planning, spam filters, language recognition and translation, credit checks and fraud alerts, book and music recommendations, and energy management systems. It is being used in law, transport, education, healthcare and security, and for engineering, economic and scientific modelling. Advanced manufacturing is almost entirely automated. 

 

In the various forms that AI and digital fabrication takes on their way to the construction site, they will become central to many of the tasks and activities involved. In this, building and construction may no different from other industries and activities, however the path of AI in construction will be distinct and different from the path taken in other industries. This path dependence can vary not just from industry to industry, but from firm to firm as well.

 



[i] In 2019 the International Standard 19650 was released, providing a framework for creating, managing and sharing digital data on built assets. https://www.iso.org/obp/ui/#iso:std:iso:19650:-1:ed-1:v1:en 

Monday 27 July 2020

Construction AI

Three industry scenarios

 

McKinsey’s Artificial Intelligence: Construction Technology’s Next Frontier (Agarwal et al 2018) is one of a series of recent papers from the management consultants on AI, automation and infrastructure. They identify five AI-powered applications, and use cases that have already arrived in other industries, that can be applied to construction. This is a practical approach that seems to target major contractors, and is a different approach to previous reports that could have been primarily intended for public sector clients. McKinsey has been seriously developing their infrastructure practice for some years now, positioning themselves for the global infrastructure boom they forecast over the next few decades. The five industry applications are:

  •  Transportation route optimization algorithms for project planning optimization;
  •  Pharmaceutical outcomes prediction for constructability issues
  •  Retail supply chain optimization for materials and inventory management
  •   Robotics for modular or prefabrication construction and 3-D printing;
  •  Healthcare image recognition for risk and safety management.

Each of these has a short discussion with some examples of crossover potential. They are all plausible extensions of current technology, and in robotics, 3-D printing and drones, leading construction firms are already well advanced. Using AI for optimization is obvious (Gans 2018), and is addressed below (see figure 2), but construction firms typically contract out specialized tasks such as design and logistics, rather than invest in the hardware and software development needed (Manly and XXX). Its questionable whether McKinsey makes a convincing case for using AI in construction. Are these are the pathways into construction for AI, or the only ones?

McKinsey also looks at some machine learning algorithms that are relevant to contractors, and briefly assesses their potential engineering and construction applications. Despite their extensive reporting on BIM elsewhere there is no discussion of the potential use of AI in design and engineering, or in restructuring processes. They do have a generic framework for types of machine learning, and they suggest algorithms will be useful for: refining quality control and claims management; increasing talent retention and development; boosting project monitoring and risk management; and constant design optimization.


If McKinsey has a more nuanced story to tell on pathways for AI into construction it might look something like the scenarios depicted by the World Economic Forum and the Boston Consulting Group in their Future Scenarios and Implications for the Construction Industry (WEF/BCG 2018). This scenario analysis is the second, final step in their Future of Construction project, which has involved people from industry and researchers from a wide range of organizations, after the Shaping the Future of Construction report (WEF/BCG 2016). They use infrastructure and urban development Industry (IU) to describe what has elsewhere been called the built environment sector.

The three future scenarios the WEF describe make technological context central to the future form of the industry. The scenarios depict three extreme yet plausible versions of the future. Each scenario is used to extrapolate implications for the industry, identifying potential winners from technological transformation, and the range of examples and ideas shows the value of such a widespread collaboration between industry, government and academia. The WEF does not say how far into the future they are looking, although it seem to be a lot further than McKinsey:

1.       In Building in a virtual world, virtual reality touches all aspects of life, and intelligent systems and robots run the construction industry. Interconnected intelligent systems and robots run the IU, software players will gain power, and new businesses will emerge around data and services.

2.       In Factories run the world, a corporate-dominated society uses prefabrication and modularization to create cost-efficient structures. The entire IU value chain adopts prefabrication, lean processes and mass customization, with suppliers benefiting the most from the transition and take advantage of new business opportunities through integrated system offerings and logistics requirements.

3.       In A green reboot, a world addressing scarce natural resources and climate change rebuilds using eco-friendly construction methods and sustainable materials. Innovative technologies, new materials and sensor-based surveillance ensure low environmental impacts, so players with deep knowledge of materials and local brownfield portfolios thrive on the new business opportunities around environmental-focused services and material recycling.

It is important to keep in mind that scenarios are not predictions of the future. Rather, they outline a broad spectrum of possible futures. In the real future, the construction industry will most probably include elements of all three, as the supply side of changes in demand for different types of building.

One issue is where the industry is at in regard to technology take-up, now that there is widespread recognition of the reality of a digital future. Will construction industry development over the next decades absorb the impacts of new technology and be gradual, changing industry practice over time without significantly affecting industry structure or dynamics? Given the entanglement of economic, social, political, and legal factors in the construction technological system this might be the case, however there are good reasons to think this may be wrong. Machine learning, AI, automation and robotics are an interconnected set of technologies that are evolving quickly, enabled by expanding connectivity and the massively scaleable hardware available today.

 

In 2016 a scenario analysis called Farsight for Construction, looking at the future of the building and construction industry in Queensland, Australia, was released (Quezada et al, 2016). The scenarios describe “four plausible futures for Queensland’s construction industry over the coming two decades, with a focus on impacts for jobs and skills. Each scenario consists of a description of Queensland’s construction industry in the year 2036, a narrative of how the scenario came about, and a commentary on plausibility.” In the figure below Australia is substituted for Queensland.

Figure 1.

Source: Quezada et al, 2016.


If we think of the structure of the construction industry as a pyramid of different sized firms, there is a broad base of tradesmen and small firms at the bottom, followed by a deep layer of medium sized firms, and a small top triangle with a few large firms. Some of those large firms, and some of their major clients, are clearly on the technological frontier, and their investment in capability and capacity should deliver significant increases in efficiency and productivity, and probably scale. Some medium-size firms are also making these investments, and also have access to technologies like algorithmic optimisation, platform-based project management, robotic, VR and AR applications and so on. The WEF Shaping the Future of Construction report (WEF/BCG 2016) included snapshots of what a range of firms at the frontier were doing. These examples reflect the diversity of the industry, and were missing from McKinsey’s high level analysis.

A period of technology-driven restructuring of the building and construction industry may be about to start, similar to the second half of the 1800s when the new materials of glass, steel and reinforced concrete arrived, which led to new methods of production, organisation and management. There are many implications of such a restructuring. Some firms are rethinking their processes in response to developments in AI, robotics and automation as capabilities improve quickly and the range of new products using these technologies expands. Many firms, however, are not. Meanwhile, firms at the frontier are exploring new technology and pushing the boundaries of what is possible, and are inventing new processes.

 

References

Agarwal, R., Chandrasekaran, S. and Sridhar, S. 2016. Artificial Intelligence: Construction Technology’s Next Frontier, McKinsey & Co.

Quezada, G., Bratanova, A., Boughen, N. and Hajowicz, S. 2016. Farsight for Construction: Exploratory scenarios for Queensland’s construction industry to 2036, CSIRO, Australia.

WEF/BCG, 2016. Shaping the Future of Construction: A Breakthrough in Mindset and Technology, World Economic Forum and the Boston Consulting Group, Geneva.

WEF/BCG, 2017. Future Scenarios and Implications for the Construction Industry, World Economic Forum and the Boston Consulting Group, Geneva.