Technology Assessment -3D printing Introduction

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Technology Assessment - 3D printing

Introduction Technology assessment (TA) was introduced when it became clear that new technologies had a number of undesirable social, occupational, environmental, cultural, technical and economic side effects. To avoid these consequences, technology users are encouraged to systematically consider and evaluate positive and negative effects of an emerging technology, or new applications of an existing technology (Baumber, 2013). A formal approach to technology assessment was pioneered in the 1970s by the Office of Technology Assessment OTA of the US Congress to aid the democratic control of scientific and technological innovations (EPTA, 2013). Technology assessment is an essential tool used to inform decision makers on technological developments and entailing social aspects (Van den Ende et al, 1998). Ethical committees can be seen as a form of argumentative technology assessment in that they aim to broaden the scope of arguments that are applied in the assessment process (Van Est et al, 2011). Possible confusion exists between the concepts of product testing which attempts to improve product design, and technology assessment which explores the implications of a technological innovation (Porter, 1995). What characterises TA is the specific combination of knowledge creation about a technology and the evaluation of this knowledge from a societal perspective, together forming the recommendations made to politics and society. TA is thus both interdisciplinary and transdisciplinary (Grunwald, 2009). The discipline of Industrial Ecology offers tools and analysis methods for decision makers in pursuit of sustainable technology. It is based on a natural paradigm suggesting that an industrial ecosystem may behave in a similar way to the natural ecosystem wherein everything gets recycled. Industrial ecology addresses the need for appropriate quantification and calculation of resource flow in a globalised economy, and the transition of production processes from linear open loop systems where materials end up as waste, to closed loop systems where waste becomes resource and input for new processes. The Cradle-to-Cradle philosophy, conceived by McDonough & Braungart (2002) and espoused by green engineering, represents a framework where materials flow in a closed regenerative loop which sets the vision for a sustainable world. This report assesses the rapidly evolving technology of three-dimensional (3D) printing and reviews the possible environmental, social and economic impacts. It investigates whether the technology has the potential to offer a cradle-to-cradle solution for the manufacturing process, and whether it potentially promotes closed loop system thinking and industrial symbiosis by eliminating waste through reuse and full resource recovery.


What is 3D printing 3D printing involves building up a solid object by progressively adding layers of source material, hence the alternative name ‘additive manufacturing’. Industrial 3D printers have existed since the early 1980s and have been used extensively for rapid prototyping in concurrent engineering and research purposes (eFunda, 2013). A wider interest in the technology only occurred in the past decade since 3D printing is becoming increasingly affordable and applicable to a variety of industries and purposes.

How it works 3D printers can be described as model-making machines that extrude filament (source material) to create predetermined three dimensional structures. 3D printing is based on existing engineering knowledge that involves rendering a computer assisted design (CAD) drawing of an object into a digital 3D model, and feeding this blueprint into the 3D printer. 3D printing is used in workshops and laboratories and for personal desktop printing. Fused Deposition Modeling (FDM) is a method used by engineers to model complex geometries using two materials: modeling material, which constitutes the finished piece, and support material, which acts as scaffolding. Filaments are fed from the material bays to the print head, which moves in X and Y coordinates, depositing material to complete each layer before the base moves down the Z axis and the next layer begins. After the build the user breaks the support material away or dissolves it in detergent and water, making the part ready to use (Stratasys, 2013). Ultrasonic Consolidation (UC) is another additive manufacturing method, based on the ultrasonic welding of a sequence of metal foils (AMRG, 2011). Precision Casting uses 3D printing to print industrial metal objects in a range of densities and sizes (Wisconsin Precision, 2013).

Input & outputs Inputs/filaments for 3D printing are made from a range of substances such as polymers, glass, rubber, graphene, metal, even human cells. 3D printer machines are made from a variety of materials including wood, metals, plastics, with variable material inputs and wastes during production, depending on the nature and type of machine. The process of 3D printing causes comparably little waste (Hague, 2010). While traditional ’subtractive’ manufacturing processes remove up to 95 per cent of the raw material to arrive at a finished component, additive machines only use the material they need to make the part. Even without changing the component, additive manufacturing requires 26 times less material extraction of out of the ground to make it than traditional processes (Hague, 2010). RepRap is one open-source project that offers the free download of all information, design and plans needed to build a 3D printer for domestic use (Devijer, 2011). While the production of a 3D printer still involves resource inputs and wastes, future maintenance can prove to be highly eco- and consumer-friendly when all parts of the printer can be replaced (pre-produced as spares) by the printer itself. This option can end the problem of built-in obsolescence in consumer goods, and make the life cycle span of a 3D printing machine appreciable. The two dominant filaments for 3D desktop printing are ABS (acrylonitrile butadiene styrene) and PLA (polylactic acid), both thermoplastics. Plastic comes in two main categories: thermosets and thermoplastic. Thermosets are plastics that once polymerised cannot be broken down or recycled.


Thermoplastics can be recycled as the bonds are reversible and can be heated and reformed (MATSE, 2013). ABS is derived from petroleum. PLA resin is plant based, derived from renewable resources, such as corn starch, tapioca, or sugarcane. In 2010 PLA was the second most consumed bioplastic in the world (Ceresana, 2013). The use of PLA filament reportedly consumes 32 percent less energy than working with ABS plastics, due to its particular material properties (Makerbot, 2013). The costs for 1 kg of PLA pellets starts at around $2 (Alibaba, 2013).

PLA pellets

(Source: Filabot 2013)

The most promising system for the recycling of used PLA is the LOOPLA process by Galactica. The process allows an almost 100% recovery of the PLA content. PLA waste, both post-industrial and post-consumer, is shredded and moved into a reactor and, with the help of a solvent, converted back into lactic acid. The recycling process is described as virtually endless, as the solvent can be used again and again. The quality of the lactic acid recovered arrives almost starting point, and can be used to make virgin-quality PLA (Loopla, 2011).

End-of-life options for PLA wastes

(Source Loopla.org)

http://www.loopla.org/cradle/cradle.htm�


Industrial symbiosis, a subset of industrial ecology, places particular focus on material and energy exchange. The Filabot concept -still in prototype form- is an example for industrial symbiosis, where waste plastics are grinded and turned into a resource for extruding filament. In the process the granular filament produced from shredded household plastic waste is feed into a 3D printer that melts and extrudes the powder into thermoplastic by selective heat sintering. The shredding device itself can be produced using a 3D printer (Filabot, 2013). In the field of rapid production technology the high end 3D engineering printer M-FLEX creates parts from metal, tungsten, glass, sand or ceramic, with the capacity to print entire engine castings for helicopters or replace broken pumps in oil fields within days. To achieve the same outcome with traditional ’subtractive’ manufacturing would take months (Ex One, 2013).

(Source: Ex One 2013)


Potential uses & problems solved 3D printing has a wide range of possible applications and the potential to solve an array of problems in a variety of different contexts. Manufacturers use 3D printers to create models and prototypes for new product design and testing, and build finished goods in low volume. Educators use the technology to elevate research and learning in science, engineering, design and art. Individuals and entrepreneurs use 3D printing to expand manufacturing into the home, creating customised devices and inventions.

Potential uses A small list of possible applications for 3D printing includes industrial prototyping, architecture, artefact modeling, spacecraft components, replacement body parts, medical equipment and organs, machinery, nanotechnology, lightweight hinges for aircraft, replacement teeth, clothing, consumer goods, even food (NASA, 2013). 3D printing is applied by scientists at Queensland University where surgeons test to perform reconstructive surgery by printing biodegradable scaffolds that can patch damaged skulls and encourage new bone growth, and grow body parts such as ears and noses (Dargaville, 2013). Researchers at Glasgow University have developed a new process to print drugs through ‘reactionware’ made from a polymer gel which sets at room temperature (Cronin, 2012). The ‘3D Printed Refugee Town’ is a project of the Birmingham School of Architecture in collaboration with the UK government. The project deploys the Contour Crafter, a large automated digital fabrication device, seeking to advance refugee support and foreign aid with refugee ‘towns’ that can be created/printed within days. The project involves capacity building through local businesses educating refugees how to use the device to 3D-print the goods they need to provide and support themselves (RIBA, 2011). Dutch architects DUS see entire houses built using 3D printing, with components from bioplastics to be printed on-site using a large custom-built printer called the KamerMaker. Certain areas of the house will be printed by use of organic materials such as potato starch or by means of recycled materials like shredded plastic bottles. DUS assert such printing machines will increasingly be used for domestic manufacturing as “DIY print-your-own-home” projects and will be available in the public domain or rented for the time of usage (DUS, 2013). In Bahrain, large-scale coral-shaped structures are 3D printed from sandstone-like material, to encourage coral polyps to colonise and regenerate damaged reefs. The printed structures used for artificial reef creation have a neutral pH, unlike concrete (Sustainable Oceans International, 2013). Further applications of 3D printing are the creation of open-source scientific equipment or other science-based applications like reconstructing fossils in palaeontology, replicating artefacts in archaeology or the reconstruction of heavily damaged evidence for crime scene investigations.


Problems solved The globalised economy ships vast amounts of resources, raw materials and consumer goods around the globe in freighters that need for one trip more crude oil than all cars of entire nations together in one year (OECD, 1996). 3D printing has the potential to substantially cut down on time, costs and resources for packaging and transport. Items can be shared for instant review or collaboration without the need of shipment by solely transmitting the digital blueprints so the item can be recreated on the spot. 3D printing can promote innovation as it reduces the barriers for entry to manufacturing. If a design can be shaped on a computer, it can be turned into an object. Prototypes can be tested and modified following the feedback from early users. Trying out new products will become less risky and less costly. Peer to peer sharing in 3D printing is a concept whose potential is just being noticed. As open-source programmers collaborate by sharing software code, engineers are already starting to collaborate on open-source designs for objects and hardware. With open source 3D printers the open source paradigm is gaining momentum for hardware and software but also for the production of Open Source Appropriate Technologies that focus on sustainable development (Pearce, 2012). Thousands of blueprints have already been uploaded by engineers and designers to open source electronic prototyping platforms where data can be easily accessed and shared for 3D printing (Arduino 2013). 3D printing touches on the 12 principles of green engineering by aiming at the prevention of waste, the maximisation of energy, space, and time efficiency, and a use of materials that is “output pulled” rather than “input pushed”. The material composition promotes disassembly and value retention, and the design includes integration and interconnectivity with energy and materials flows that are renewable rather than depleting.


Analysis of impacts & discussion

Environmental impacts Western economies are stuck in a self-perpetuating inertia created by large fossil fuel-based energy systems that inhibits public and private efforts to introduce alternative technologies and consumption pathways, and to alter current infrastructures towards sustainable alternatives. This condition describes Unruh as “Carbon Lock-In” (Unruh, 2000). The source of Carbon Lock-In inertia arises from the co-evolution of large interdependent networks and the social institutions and cultural practices that support and benefit from system growth. The growth of the system is fostered by increasing returns to scale (Unruh, 2000). Manufacturing industries are the world’s third largest polluting sector after energy and transport (EEA, 2004). Engineering perspectives are particularly critical in terms of the ability to scale up manufacturing (MacGill, 2008). The industrial revolution made mass production of goods possible, thereby introducing economies of scale. 3D printing is a manufacturing technology which does the opposite. 3D printing is about mass customisation at reduced costs. Additive manufacturing makes creating single items as cheap as it is to produce thousands and thus undermines economies of scale. Leduc et al (2013) propose with the concept of circular metabolism a sustainable systems approach where an outgoing flow is not considered waste, but a flow with a remaining quality. While most systems ‘suffer’ from linear metabolism, achieving and promoting sustainable development will require future systems to internalise the concept of circular metabolism. The principles behind 3D printing have the potential to marry the paradigms of Cradle-to-Cradle and Industrial ecology, where wastes of others are used as resource, and Eco Efficiency, as reuse is not “just downcycling or a transfer of wastes to another place” as McDonough critiqued, but occurs at the place of production and consumption. By printing products locally, 3D printing saves energy, transportation and raw materials in the production, transport and packaging process, and by creating filament from waste it closes the engineering loop for material throughput.


Social impacts Bhamra et al (2007) argue that in the consumption-focused capitalist model of western societies the industry sector needs to change and internalise a needs-focused approach at the strategic level, to advance design and development of profitable products which are both environmentally and socially responsible. 3D printing technology operates on a needs-based approach, and could lead to decentralised business processes and reverse the urbanisation that accompanies industrialisation, thus eliminating the need for factories when communities can produce items on the spot when needed. By reducing the need for factory workers, 3D printing has the potential to undermine the advantage of low-cost low-wage countries, thus repatriate manufacturing capacity to the developed world. It could be argued that this may not create many jobs since the technology is less labour-intensive than standard manufacturing, but as the current capitalistic system thrives on the reduction of costs and labour, traditional jobs are going to be lost anyway, and alternative employment options have to emerge. 3D printing offers a new field of employment specialisation, in both hardware and software environments. What sets 3-D printing apart from past innovations is the role of the consumer. Traditional production and manufacturing have a linear chain of events: an identifiable product designer, manufacturer, distributor and retailer. Additive manufacturing upends the traditional system by allowing consumers to get involved in the design process. 3D printing is a shift towards concurrent or simultaneous engineering, where design of the product and the design of the manufacturing process occur together. This can shortcut the iterative steps in the engineering process.

Engineering process

(Source: Baumber, 2013)

3D printing is undergoing a patent boom, with more than 6,800 patent applications received in the last decade by the US Patent and Trademark Office (USPTO 2013). In February 2014 key patents targeted at 3D printing will expire. This will most likely impact on the world of fabrication. One estimate suggested that the global 3-D printing/additive manufacturing market had reached $2.2 billion in 2012 (NBC, 2013). 3D printers can cost hundreds of thousands of dollars, but are also available in desktop models priced at around $1,000 (CNBC, 2013). While there is no upper limit to the costs, the currently cheapest personal 3D printer (and scanner) is the “Peachy Printer” for $100. The crowdfunded open source project emphasises ethical code of conduct by informing customers of safe practices and safety equipment such as material data sheets and best practice instructions, and by providing free laser safety glasses and gloves with every printer (Peachyprinter.com, 2013).


Risks, uncertainties and information gaps For emerging technologies there can be little certainty in questions of potential scale of abatement, speed of deployment, costs and wider societal implications (MacGill, 2008). 3D printing also comes with a range of uncertainties, risks and unknowns.

Risks & Uncertainties Most of the key uncertainties in assessing possible sustainable technology options hinge on their technical status (MacGill, 2008). Research in industrial ecology focuses on technological innovation such as improvements in eco-efficiency, environmental designs and material flow analysis (Van Beers, 2007). The cornucopian paradigm promoted by futurists and industry leaders claims that progress and provision of material items for mankind can be met by similarly continued advances in technology. Authors Huesemann critique this simplistic approach and stress that negative unintended consequences of technology are inherently unpredictable and unavoidable (Huesemann, 2011). One risk is the misuse of the technology, i.e. for the production of weapons or auxiliaries for fraud. Blueprints emerged online for a plastic gun to be manufactured on high tech 3D printers, and criminals used computer-aided design and 3D printers to manufacture “sophisticated” ATM skimming devices to fleece Sydney residents (itnews, 2013). Risks to health imposed by 3D printing are yet to be researched, a lack of literature exists whether harmful chemicals are emitted during the process of 3D printing, and to which extend and consequence. A study by Illinois Institute of Technology is the first to measure airborne particle emissions from commercially available desktop 3D printers that heat thermoplastic feedstocks to build 3D objects. Similar processes have been shown to have significant aerosol emissions in other studies using a range of plastic feedstocks, but mostly in industrial environments (Stephens, 2013). A further risk from an increased uptake of 3D printing are enthusiastic technology adopters that print items just for the experience of creating them, thereby collaterally wasting resources and creating more waste. Consumers and technology users must not be fooled by an assumingly guilt free method of ‘waste-free’ production and/or consumption, as all production involves some form of entropy impact. The second law of thermodynamics shows that all physical processes, natural and technological, proceed in such a way that the availability of the energy involved decreases (Ehrlich, 1993). Discussed but uncertain is how regulators will decide about 3D printing policy, and whether and how intellectual property rights protection will alter the progress of the technology. It remains to be seen whether 3D printing requires existing rules to be tightened, thus hampering innovation, or loosened, which could see IPR conflicts.


Extensions and alternatives

4D printing 4D printing allows objects to have multiple simultaneous functions or functions that can change over time. Mechanical engineering researchers at the University of Colorado have integrated "shape memory" polymer fibers into materials used for 3D printing, which means objects that are fixed into one shape can later be changed, or transformed, into a new shape under environmental stimuli such as temperature or light. The physical materials are programmed to build themselves over time, hence lending the 4th dimension to the name (Qi J. (2013).

Bioprinting Bioprinting is the production of three-dimensional engineered human tissue for medical research and therapeutic applications from clusters of human stem cells that shape through natural adhesion in different complexities to build fully functioning organs (Tasoglu, 2012). Researchers have developed a new gelatin bio-ink that can be used by 3D printing technology to produce artificial tissues (Fraunhofer Institute, 2013). Wounds are scanned and the amount and type of tissue is calculated and printed.

3D scanning 3D scanning is further spin-off, but is still in its early days. 3D scanners can turn physical, real-world objects into digital 3D colour models (Matterform, 2013).


Conclusion

This report assessed the still emerging technology of 3D printing and reviewed the possible

environmental, social and economic impacts. At this stage the technology presents itself as a

possible game changer for the problems of waste and pollution from industrialisation, transport,

packaging. 3D printing has the potential to offer cradle-to-cradle solutions for the manufacturing

process, and to advance closed loop system thinking and industrial synergies by metabolising waste

as a resource, and reducing production time, cost and material throughput. 3D printing is also

advancing the Open Source Appropriate Technology (OSAT) movement through publicly shared

blueprints and designs.

Engineers combine the scientific laws and the practical considerations required for Technology

Assessment. Australia as a modern society thriving on engineering success would benefit greatly

from the implementation of a national Technology Assessment Framework that would help to

inform policy makers and provide impartial and high quality analysis and reports about technological

developments in a broad spectrum of issues including public health, environment and energy, ICTs

and R&D policy.


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3D printing - still an adventure

Technology Assessment -3D printing Introduction

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