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=== [http://scg.mit.edu/images/MCPC_Conference_proceedings/site/papers/MCPC-045-2007.pdf RepRap: The Replicating Rapid Prototyper Maximizing Customizability by Breeding the Means of Production] ===
=== [http://scg.mit.edu/images/MCPC_Conference_proceedings/site/papers/MCPC-045-2007.pdf RepRap: The Replicating Rapid Prototyper Maximizing Customizability by Breeding the Means of Production] ===
Z. Smith, “RepRap: The Replicating Rapid Prototyper Maximizing Customizability by Breeding the Means of Production.”
'''Z. Smith, “RepRap: The Replicating Rapid Prototyper Maximizing Customizability by Breeding the Means of Production.”'''
 
Abstract:
 
Consider the wolves that you see being led down the street every day. Their appearance ranges
from the whimsical to the grotesque, and their adult body size covers a span unmatched by any
other species. This virtuoso and antic variety was created by one of humanity's oldest and grandest
technologies: genetic engineering. We have been customizing life since the invention of
agriculture in Mesopotamia around 9500 BCE (Wikipedia, 2007).
 
Nowadays much of that customisation is done industrially, though the techniques still retain an
important characteristic that they have had over the millennia: they can be done by a single person
possessing equipment no more advanced than a breeding pen or a potting shed. Even the latest
twist of the helix ─ direct manipulation of DNA ─ requires modest wherewithal well within the
resources of an individual (Dyson, 2006).


=== [http://opus.bath.ac.uk/18661/2/bradshaw.pdf The Intellectual Property Implications of Low-Cost 3D Printing]===
=== [http://opus.bath.ac.uk/18661/2/bradshaw.pdf The Intellectual Property Implications of Low-Cost 3D Printing]===
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of paradigm shift in consumer-producer-relationship.
of paradigm shift in consumer-producer-relationship.


===[www.researchgate.net/publication/233748500_FIRST_STEPS_TOWARDS_COLLABORATIVELY_EDITED_DESIGN_FOR_ADDITIVE_MANUFACTURING_KNOWLEDGE/file/79e4150b1408156951.pdf FIRST STEPS TOWARDS COLLABORATIVELY EDITED DESIGN FOR ADDITIVE
===[http://www.researchgate.net/directory/publications/A First Steps Towards Collaboratively Edited Design For Additive Manufacturing Knowledge]===
MANUFACTURING KNOWLEDGE]===
'''Doubrovski, E. L., J. C. Verlinden, and I. Horvath. "FIRST STEPS TOWARDS COLLABORATIVELY EDITED DESIGN FOR ADDITIVE MANUFACTURING KNOWLEDGE."'''
'''Doubrovski, E. L., J. C. Verlinden, and I. Horvath. "FIRST STEPS TOWARDS COLLABORATIVELY EDITED DESIGN FOR ADDITIVE MANUFACTURING KNOWLEDGE."'''


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with a simple CFS.
with a simple CFS.


===[http://annals.fih.upt.ro/pdf-full/2012/ANNALS-2012-1-16.pdf  ACCELERATING THE INNOVATION PROCESS WITH THE HELP
===[http://annals.fih.upt.ro/pdf-full/2012/ANNALS-2012-1-16.pdf  Accelerating the Innovation Process with the Help of Open Source Prototyping Hardware]===
OF OPEN SOURCE PROTOTYPING HARDWARE]===
'''MERKEL, Andreas, Hendrik HOPF, and Egon MÜLLER. "ACCELERATING THE INNOVATION PROCESS WITH THE HELP OF OPEN SOURCE PROTOTYPING HARDWARE.'''
'''MERKEL, Andreas, Hendrik HOPF, and Egon MÜLLER. "ACCELERATING THE INNOVATION PROCESS WITH THE HELP OF OPEN SOURCE PROTOTYPING HARDWARE.'''


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hardware and software, and describe future development directions.
hardware and software, and describe future development directions.


===[http://www.criticalmaking.com/ddimit/wp-content/uploads/2011/02/SSHRC_DigEcon_DDF.pdf The Materialization of Digital Information
===[http://www.criticalmaking.com/ddimit/wp-content/uploads/2011/02/SSHRC_DigEcon_DDF.pdf The Materialization of Digital Information and the Digital Economy]===
and the Digital Economy]===
'''Ratto, Matt, and Robert Ree. "The Materialization of Digital Information and the Digital Economy Knowledge Synthesis Report." (2010).'''
'''Ratto, Matt, and Robert Ree. "The Materialization of Digital Information and the Digital Economy Knowledge Synthesis Report." (2010).'''


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Recent improvements in the area of Fused Deposition Modelling have led to the creation of inexpensive desktop based Rapid Prototypers such as the Replicating Rapid-Prototyper (RepRap) allowing the individual the freedom to fabricate three dimensional parts of their own, however print resolutions of the parts are not on the same level as commercially based systems. It has been observed that adjusting the certain parameters on the polymer melt extruder such as the extruder nozzle diameter, nozzle angle, and liquefier length ultimately affects the extruded melt flow behaviour [17]. These parameters are important factors to consider for an improved design. This thesis presents the results of the computational and experimental work that shows the effect of taking the original specifications of the RepRap extruder and aims to show how reducing nozzle exit diameter and varying nozzle angle has resulting effects on the pressure drop and the flow behaviour of the melt. The results show that optimization of the flow rate can have significant effects on the extruded melt and it also shows limitations on how small the nozzle exit diameter can be before the resulting pressure drop becomes too large such that the motor cannot provide enough torque to drive the flow. Ultimately, the proposed redesign suggests that the RepRap’s extruder nozzle diameter can be decreased from 0.5mm to 0.3mm with a nozzle angle of 120 degrees which will decrease the diameter of the extruded melt contributing to better resolutions. The report further shows the consequences of further decreasing the diameter and nozzle angle and concludes with an experiment that observes the melt flow behaviour of the melt to ensure that PCL is a valid candidate material for Fused Deposition Modelling in Rapid Prototyping.
Recent improvements in the area of Fused Deposition Modelling have led to the creation of inexpensive desktop based Rapid Prototypers such as the Replicating Rapid-Prototyper (RepRap) allowing the individual the freedom to fabricate three dimensional parts of their own, however print resolutions of the parts are not on the same level as commercially based systems. It has been observed that adjusting the certain parameters on the polymer melt extruder such as the extruder nozzle diameter, nozzle angle, and liquefier length ultimately affects the extruded melt flow behaviour [17]. These parameters are important factors to consider for an improved design. This thesis presents the results of the computational and experimental work that shows the effect of taking the original specifications of the RepRap extruder and aims to show how reducing nozzle exit diameter and varying nozzle angle has resulting effects on the pressure drop and the flow behaviour of the melt. The results show that optimization of the flow rate can have significant effects on the extruded melt and it also shows limitations on how small the nozzle exit diameter can be before the resulting pressure drop becomes too large such that the motor cannot provide enough torque to drive the flow. Ultimately, the proposed redesign suggests that the RepRap’s extruder nozzle diameter can be decreased from 0.5mm to 0.3mm with a nozzle angle of 120 degrees which will decrease the diameter of the extruded melt contributing to better resolutions. The report further shows the consequences of further decreasing the diameter and nozzle angle and concludes with an experiment that observes the melt flow behaviour of the melt to ensure that PCL is a valid candidate material for Fused Deposition Modelling in Rapid Prototyping.


===[http://download.springer.com/static/pdf/855/art%253A10.1007%252Fs11740-010-0286-6.pdf?auth66=1362516392_f9bd0fb2ae523eaab27f31d5647b3bdb&ext=.pdf Open production: scientific foundation for co-creative product
===[http://download.springer.com/static/pdf/855/art%253A10.1007%252Fs11740-010-0286-6.pdf?auth66=1362516392_f9bd0fb2ae523eaab27f31d5647b3bdb&ext=.pdf Open production Scientific Foundation for co-creative product realization]===
realization]===
'''Wulfsberg, Jens Peter, Tobias Redlich, and Franz-Ludwig Bruhns. "Open production: scientific foundation for co-creative product realization." Production Engineering 5.2 (2011): 127-139.'''
'''Wulfsberg, Jens Peter, Tobias Redlich, and Franz-Ludwig Bruhns. "Open production: scientific foundation for co-creative product realization." Production Engineering 5.2 (2011): 127-139.'''


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adequate framework for
adequate framework for


===[http://www.worldscientific.com/doi/pdf/10.1142/S021987701100260X PRODUCT DEVELOPMENT IN OPEN DESIGN
===[http://www.worldscientific.com/doi/pdf/10.1142/S021987701100260X Product Development in Open Design Communities A Process Perspective]===
COMMUNITIES: A PROCESS PERSPECTIVE]===
'''Raasch, Christina. "Product Development In Open Design Communities: A Process Perspective." International Journal of Innovation and Technology Management 8.04 (2011): 557-575.'''
'''Raasch, Christina. "Product Development In Open Design Communities: A Process Perspective." International Journal of Innovation and Technology Management 8.04 (2011): 557-575.'''


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discussion focusses on different aspects of modularity as well as the availability of lowcost
discussion focusses on different aspects of modularity as well as the availability of lowcost
tools.
tools.
===[http://reprap.org/mediawiki/images/archive/2/25/20100412224301!SpoolHead_FinalReport.pdf Wire embedding 3D Printer]===
'''Bayless, Jacob, Mo Chen, and Bing Dai. "Wire embedding 3D printer." (2010).'''
Abstract:
The RepRap 3D printer is an open-source rapid prototyping machine capable of producing
most of its own structural components. This printer can be built and run at a much lower
price than a commercial 3D printer, and used to create copies of itself. Its first model, Darwin,
was released online in 2008. It can print durable and accurate parts from thermoplastic
materials, but it cannot currently print with electrically conductive materials. The Gada
Prize, established in 2010 to advance the RepRap project, is a $80,000 grand prize and
$20,000 interim prize that will be awarded to a machine like the RepRap which meets several
additional specifications, including the ability to print conductors.
The wire-embedding 3D printer project adds a wire-printing tool head, “SpoolHead”, to
the RepRap Darwin model. The SpoolHead is a promising new approach to manufacturing
hybrid wire-and-plastic parts, and an attempt to meet the conductive materials requirement
of the Gada prize.
This report documents the development and testing of the first SpoolHead prototype, a
wire-printing mechanism that uses a servo-actuated mechanical pencil to insert metal wires
into the heated surface of a printed thermoplastic part. The wires are then to be cut by a
solenoid-actuated mechanism that shears the wire inside the main tube of the print head.
Benchtop tests performed to validate the design philosophy of the SpoolHead gave positive
results. The print head was then manufactured and tested on two designs proposed at the
outset of the project, a rectangle and a spiral. The SpoolHead was able to print the spiral
design to within the specified ±0.5 mm tolerances outlined at the beginning of the project.
The printed rectangle was out of specification, with straightness errors of up to 0.8 mm and
dimensions short by 1 mm of the design length. However, the errors responsible for this have
been identified and can be easily resolved in future versions.
It was found that the cutter design failed, requiring manual intervention in the cutting
process. While alternative methods have been proposed to improve the cutter, a fully satis-
factory solution remains to be found.
Numerous recommendations are presented that outline how the future development of the
SpoolHead should proceed, beginning with investigating replacing the cutter. Methods for
future miniaturization of the device are presented, as well as plans for improved electronics
and software.
=== [http://lmrt.mit.edu/publications/2012/Miller_NMAT_2012.pdf Rapid casting of patterned vascular networks for perfusable engineered three-dimensional tissues] ===
'''Bhatia, Sangeeta N., and Christopher S. Chen. "Rapid casting of patterned vascular networks for perfusable engineered three-dimensional tissues." (2012).'''
Abstract:
In the absence of perfusable vascular networks, three-
dimensional (3D) engineered tissues densely populated with
cells quickly develop a necrotic core1 . Yet the lack of a
general approach to rapidly construct such networks remains
a major challenge for 3D tissue culture2–4 . Here, we printed
rigid 3D filament networks of carbohydrate glass, and used
them as a cytocompatible sacrificial template in engineered
tissues containing living cells to generate cylindrical networks
that could be lined with endothelial cells and perfused
with blood under high-pressure pulsatile flow. Because this
simple vascular casting approach allows independent control
of network geometry, endothelialization and extravascular
tissue, it is compatible with a wide variety of cell types,
synthetic and natural extracellular matrices, and crosslinking
strategies. We also demonstrated that the perfused vascular
channels sustained the metabolic function of primary rat
hepatocytes in engineered tissue constructs that otherwise
exhibited suppressed function in their core.
===[https://dspace.lboro.ac.uk/dspace-jspui/bitstream/2134/9763/12/Entry_Level_RP_.pdf  How Well Can They Cope With Geometric Complexity?]===
'''Pei, Eujin, R. Ian Campbell, and Deon de Beer. "Entry-level RP machines: how well can they cope with geometric complexity?." Assembly Automation 31.2 (2011): 153-160.'''
Abstract:
The literature review provides an overview of RP technologies, followed by a
discussion on the different levels of complexity in objects. The paper continues with
a discussion on the definition of entry level rapid prototyping, followed by a number
of experiments to explore the limitations of an entry level RP system when
fabricating complex models, and to compare the results obtained with those from a
professional RP machine using standardised build parameters and the same ABS
material.
===[https://dspace.lboro.ac.uk/dspace-jspui/bitstream/2134/9759/15/AM_in_South_Africa.pdf Additive Manufacturing in South Africa Building on the Foundations]===
'''Campbell, R. I., D. J. De Beer, and Eujin Pei. "Additive manufacturing in South Africa: building on the foundations." Rapid Prototyping Journal 17.2 (2011): 156-162.'''
Abstract:
In a previous Rapid Prototyping Journal paper, the authors reviewed the first decade of Rapid
Prototyping (RP) use within the Republic of South Africa (RSA). The paper analysed its
strengths, weaknesses, opportunities and threats, and proposed a “road-map” for future
development. Much has happened in the intervening years since that article was published and
this paper seeks to update readers on the current situation in RSA. In particular, it reports the
extensive development of research in the field of RP and Additive Manufacturing (AM).
===[http://people.bath.ac.uk/en3cl/design/freeing_design/freeing_information.pdf Design, Fabrication, and Characterization of a Low-Cost Flexural Bearing Based 3D Printing Tool Head]===
'''Ramirez, Aaron Eduardo. Design, fabrication, and characterization of a low-cost flexural bearing based 3D printing tool head. Diss. Massachusetts Institute of Technology, 2010.'''
Abstract:
This thesis discusses the design, characterization and optimization of a low-cost additive rapid-
prototyping tool head for a technology known as Fused Filament Fabrication for use in an
educational curriculum. Building a 3D printer represents an excellent educational opportunity as
it requires knowledge in electronics, mechanics, and thermal-fluids engineering; this particular
design also includes a flexural bearing, introducing students to a new and important class of
machine element. Polymer flow through the extruder is modeled as pipe flow with pressure
drops using Bernoulli's equation with viscous losses; the model predicts that the pressure
1
required to extrude is proportional to , where d is the nozzle diameter. Three different extruder
designs are considered; a piston-based design, an auger-based design, and a pinch-wheel design.
The pinch wheel design best meets the functional requirements after comparing the designs
based on factors such as complexity and controllability. Flexural bearings are selected to provide
a preload against the polymer filament; HDPE was chosen to be the flexure material after
considering factors such as water-jet machinability and yield stress to elastic modulus ratio.
Thermal imaging shows that the temperature profile along the heater barrel is not uniform, with
the largest variation being 80±2.8*C in large part due to errors in heater wire distribution during
assembly. An exponential relationship is observed between the force required to extrude versus
the temperature of the heater barrel with the force required to extrude dropping to between 1 and
2N in the range of 200 to 240*C. This data suggests trade-offs between maintaining a reasonable
extruding pressure and maintaining good build resolution and speed. A discussion of the low-
cost rapid prototyping cycle follows, as well as instructions for assembly and use of the extruder.
The paper ends with several suggestions to improve extruder performance and a list of ideas for
bringing the extruder costs down.


==PV Junction Box==
==PV Junction Box==
Line 558: Line 682:
electricity than the stand-a-lone option. The extent of the benefits depends on the system
electricity than the stand-a-lone option. The extent of the benefits depends on the system
design and how to determine the optimum arrangement for a particular building site.
design and how to determine the optimum arrangement for a particular building site.
===[http://www.zeusinc.com/UserFiles/zeusinc/Documents/Zeus_Weathering_of_Plastics.pdf Zeus Technical White Paper Weathering of Plastics]===
'''Zeus Industrial Products'''
Abstract:
We are all no doubt aware of the main effect of ultraviolet (UV) radiation on ourselves – how
many of us have ended up with a red nose after a day out in the sun? Our skin is not the only
organic structure to suffer; even polymers will be affected to some degree by exposure to sunlight
and ultraviolet radiation. The main problem is that so many parameters affect the level of
exposure, and there are several ways of providing resistance to the effects.

Revision as of 16:53, 27 February 2013

RepRap Technology

RepRap – the replicating rapid prototyper

R. Jones, P. Haufe, E. Sells, P. Iravani, V. Olliver, C. Palmer and A. Bowyer, “RepRap – the replicating rapid prototyper,” Robotica, 29(1), 177-191, 2011.

Abstract:

This paper presents the results to date of the RepRap project – an ongoing project that has made and distributed freely a replicating rapid prototyper. We give the background reasoning that led to the invention of the machine, the selection of the processes that we and others have used to implement it, the designs of key parts of the machine and how these have evolved from their initial concepts and experiments, and estimates of the machine's reproductive success out in the world up to the time of writing (about 4500 machines in two and a half years).

Notes:

  • Give history of RepRap
  • Started in 2004
  • First RepRap self reproduction in 2008
  • Originally designed to print ABS
  • PLA chosen as an alternative print material as it is plant-based and biodegradable
  • 48% self replicating excluding fasteners, 13% including fasteners (For both Darwin and Mendel)
  • Mendel possible self replication of 57% (excluding fasteners) if bearings are replaced with printed plain bearings.
  • From Table 1- Mendel: Cost-350 Euros, Deposition Rate-15 mL/hr, Nozzle Diameter-0.5mm, Positioning Accuracy-0.1mm,

Open Design and the Reprap Project

D. Holland, G. O'Donnell, and G. Bennett, “Open Design and the Reprap Project,” 27th International Manufacturing Conference', 97-106, 2010.

Abstract:

This paper details the investigation of an emerging trend within technology development: ‘open design’. Improvements in communications and computing technology have made collaboration over geographically vast distances possible. This technology has already had a major impact on the field of engineering, from the development of CAD/CAE/CAM practices to the emergence of concurrent engineering. Taking the lead from open source software, open design is an approach to technology development in which technical design information is licensed in such a manner that it can be accessed, utilised, modified and redistributed by anyone. The potential implications of this concept can be inferred from the impact of open source software. A review of the existing literature on the subject was conducted. A practical demonstration of the process was undertaken, via an attempt to contribute to an existing open design technology: the RepRap. This is a low cost rapid prototyper capable of manufacturing the parts required to make a copy of itself. The ability to use resin as a construction material was identified as a requirement of the device. An approach to integrating resin extrusion within the device was selected, a suitable material identified, and an experimental rig designed and assembled. Initial test results indicated that resin extrusion is viable for the RepRap.

Notes:

  • Discusses the benefits of "open design" - advancement of technology, rapid evolution of designs, efficient debugging, ability to deal with uncertainty about a new technologies success.
  • Good brief history of the RepRap
  • Investigated the possibility of using resins as a feedstock - Used a UV curable adhesive resin
  • Created experimental, syringe-based extruder run on a 3-axis desktop CNC machine (not a RepRap)
  • Experiments to investigate feasibility, cure times, effect of mixing resin with additives, using ABS and resin, and using ABS as a support structure.
  • Found that only high viscosity resins produced acceptable print quality without any support structure.
  • ABS can be successfully use as a support material in combination with low viscosity resins. It can later be removed by submerging the part in acetone which dissolves the ABS but keeps the resin intact.

An Open Source Hardware-based Mechatronics Project: The Replicating Rapid 3-D Printer

J. Kentzer, B. Koch, M. Thiim, R.W. Jones, and E. Villumsen, “An Open Source Hardware-based Mechatronics Project: The Replicating Rapid 3-D Printer,” 2011 4th International Conference on Mechatronics', 1-8, 2011.

Abstract:

This contribution reviews the execution of an open source hardware (OSHW) project as part of the Master in Mechatronics Degree Programme at the University of Southern Denmark. There were a number of reasons that motivated us to carry out this project; educational, intellectual and research reasons. Open source projects provide unique opportunities for students to gain experience solving real-world problems. There was also a research consideration in pursuing an OSHW project. Three of the authors of this contribution are working towards a Master's Degree in Innovation and Business and wanted to carry out an OSHW project as a precursor to doing research work on the `Commercialization of OSHW Projects'. The choice of the project was all important and we choose to build a 3-D printer using information provided by the RepRap Open Source Community because this satisfied nearly all our specifications for an OSHW project. Our experiences in constructing a 3-D printer as well as documenting the areas where the open source information currently has deficiencies are documented here.

Notes:

  • Outlines the history of Open Source Hardware (OSHW) from Open Source Software
  • Use of Open Source Appropriate Technology projects in the classroom (cites Dr. Pearce)
  • Overview of building their Mendel and the problems they encountered - holes to small, firmware issues, hot end failure
  • Printed ABS400 at 260C.
  • Hot end problems- had multiple failures of PTFE thermal barrier. Switched to a PEEK barrier.
  • Switched from ABS to PLA - had problems with sticking in the nozzle, fixed with oil
  • Used Gen 3 electronics
  • Described many deficiencies in RepRap documentation

3-D Printing of Open Source Appropriate Technologies for Self-Directed Sustainable Development

J. M. Pearce, C.M. Blair, K.J. Laciak, R. Andrews, A. Nosrat, and I. Zelenika-Zovko, “3-D Printing of Open Source Appropriate Technologies for Self-Directed Sustainable Development,” Journal of Sustainable Development', 3(4), 17-29, 2010.

Abstract:

The technological evolution of the 3-D printer, widespread internet access and inexpensive computing has made a new means of open design capable of accelerating self-directed sustainable development. This study critically examines how open source 3-D printers, such as the RepRap and Fab@home, enable the use of designs in the public domain to fabricate open source appropriate technology (OSAT), which are easily and economically made from readily available resources by local communities to meet their needs. The current capabilities of open source 3-D printers is reviewed and a new classification scheme is proposed for OSATs that are technically feasible and economically viable for production. Then, a methodology for quantifying the properties of printed parts and a research trajectory is outlined to extend the existing technology to provide complete village-level fabrication of OSATs. Finally, conclusions are drawn on the potential for open source 3-D printers to assist in driving sustainable development.

Notes:

  • Defines appropriate technology
  • Appropriate technology is not well documented and shared. Need for better dissemination.
  • Commercial printers have high tolerances but expensive ($5000-$200,000) compared to ~$1000 open source printers
  • RepRap and Fab@Home started at colleges and have open source communities
  • Self-replication 6.83% with fasteners, 48% excluding fasteners
  • RepRap can print ABS, PLA, HDPE, and polycarprolactone
  • "Sequential layer deposition"
  • Open source CAD software and model sharing on Thingiverse
  • No machining skills necessary to operate 3-D printers
  • Open source printing would encourage training in CAD and design
  • Printed parts could be used in energy, farming, water, food, medical, transportation, handicrafts, housing, and industrial applications
  • Possible directly made parts include: prosthesis, tools, gears, clamps, etc.
  • Using printed part for making a casting mold
  • Post-processing is acceptable for OSAT applications
  • Most development in open source 3-D printing is from the hacking community, not currently influenced by the full potential of materials science and engineering
  • 3-D printing does not have the reliability or testing for deployment in developing countries.
  • More testing of printed parts is need along with development of testing methods to find the properties of printed materials
  • Need theoretical analysis and testing of parts to determine suitability of printing objects.

RepRap: The Replicating Rapid Prototyper Maximizing Customizability by Breeding the Means of Production

Z. Smith, “RepRap: The Replicating Rapid Prototyper Maximizing Customizability by Breeding the Means of Production.”

Abstract:

Consider the wolves that you see being led down the street every day. Their appearance ranges from the whimsical to the grotesque, and their adult body size covers a span unmatched by any other species. This virtuoso and antic variety was created by one of humanity's oldest and grandest technologies: genetic engineering. We have been customizing life since the invention of agriculture in Mesopotamia around 9500 BCE (Wikipedia, 2007).

Nowadays much of that customisation is done industrially, though the techniques still retain an important characteristic that they have had over the millennia: they can be done by a single person possessing equipment no more advanced than a breeding pen or a potting shed. Even the latest twist of the helix ─ direct manipulation of DNA ─ requires modest wherewithal well within the resources of an individual (Dyson, 2006).

The Intellectual Property Implications of Low-Cost 3D Printing

Bradshaw, S., Bowyer, A. and Haufe, P., 2010. The Intellectual Property implications of low-cost 3D printing. ScriptEd, 7 (1), pp. 5-31.

Abstract:

In the late 1970s 3D printing started to become established as a manufacturing technology. Thirty years on the cost of 3D printing machines is falling to the point where private individuals in the developed world may easily own them. They allow anyone to print complicated engineering parts entirely automatically from design files that it is straightforward to share over the Internet. However, although the widespread use of 3D printers may well have both economic and environmental advantages over conventional methods of manufacturing and distributing goods, there may be concerns that such use could be constrained by the operation of intellectual property (IP) law. This paper examines existing IP legislation and case law in the contexts of the possible wide take-up of this technology by both small firms and private individuals. It splits this examination into five areas: copyright, design protection, patents, trade marks, and passing off. Reassuringly, and perhaps surprisingly, it is concluded that – within the UK at least - private 3D printer owners making items for personal use and not for gain are exempt from the vast majority of IP constraints, and that commercial users, though more restricted, are less so than might be imagined.

A New Open Source 3D-Printable Mobile Robotic Platform for Education

Gonzalez-Gomez, J., Valero-Gomez, A., Prieto-Moreno, A., & Abderrahim, M. (2012). A new open source 3d-printable mobile robotic platform for education. Advances in Autonomous Mini Robots, 49-62.

Abstract:

In this paper we present the Miniskybot, our new mobile robot aimed for educational purposes, and the underlying philosophy. It has three new important features: 3D-printable on low cost reprap-like machines, fully open source (including mechanics and electronics), and designed exclusively with open source tools. The presented robotic platform allows the students not only to learn robot programming, but also to modify easily the chassis and create new custom parts. Being open source the robot can be freely modified, copied, and shared across the Internet. In addition, it is extremely cheap, being the cost almost exclusively determined by the cost of the servos, electronics and sensors.

IT WILL BE AWESOME IF THEY DON'T SCREW IT UP

Weinberg, M. (2010). IT WILL BE AWESOME IF THEY DON’T SCREW IT UP.

Abstract:

The next great technological disruption is brewing just out of sight. In small workshops, and faceless office parks, and garages, and basements, revolutionaries are tinkering with the machines that can turn digital bits into physical atoms. The machines can download plans for a wrench from the Internet and print out a real, working wrench. Users design their own jewelry, gears, brackets, and toys with a computer program, and use their machines to create real jewelry, gears, brackets and toys.

Changing How We Make and Deliver Smart Devices: When Can I Print Out My New Phone?

A. Schmidt, T. Doring, and A. Sylvester, “Changing How We Make and Deliver Smart Devices: When Can I Print Out My New Phone?,” IEEE Pervasive Computing, vol. 10, no. 4, pp. 6 –9, Apr. 2011.

Abstract:

The research vision of printing physical devices has been around for a decade, and in research prototypes this vision is being realized. With fabrication laboratories (fab labs) emerging around the world and with more powerful modular computing platforms becoming available, the possibility of creating innovative smart devices and ubicomp products is becoming reality.

3D Printer Toolchain

Evans, Brian. "3D Printer Toolchain." Practical 3D Printers (2012): 27-47.

Abstract:

We are still a long way from having our personal 3D printers work just like our microwaves, yet there has been a lot of progress made by a group of intrepid developers to not only give you options for how you want to use your 3D printer but to make it more reliable and easier to use. How we interact with our 3D printer is determined by the printer’s toolchain: the electronics, fi rmware, control software, and slicing software that take a 3D model to a 3D object. If you bought your 3D printer as a complete kit or preassembled, then you probably have a set toolchain provided by the kit manufacturer. On the other hand, you might be piecing your 3D printer together from a variety of sources and are choosing parts of the toolchain that best fi t your needs. Either way, this chapter is here to help you understand how these diffffff erent parts of the toolchain work together. ThThis chapter also introduces the idea of the 3D printer work fl ow as a way to use our printer’s toolchain to make 3D prints. You might later decide to upgrade parts of your toolchain, so this chapter will help give you a place to start. For example, we might want to upgrade our three-year-old MakerBot Cupcake with new electronics running new fi rmware with advanced features originally designed for a RepRap. We might also want to upgrade our slicer program to make repairing models for printing a little easier. All of this would give us a signi fi cant upgrade in an older printer’s print quality and performance, breathing new life into it.

VIRTUAL FACTORY FOR CUSTOMIZED OPEN PRODUCTION

Redlich, T. O. B. I. A. S., JENS P. Wulfsberg, and F. L. Bruhns. "Virtual Factory for Customized Open Production." Tagungsband 15th International Product Development Management Conference, Hamburg. 2008.

Abstract:

This paper regards a holistic customer integration into value creating with a focus on the development of manufacturing equipment. Therefore the paradigm of Open Production will be introduced and the practicability of openness will be evidenced by practical examples.

The Cambrian Explosion of Popular 3D Printing

Cano, Juan Luis Chulilla. "The Cambrian Explosion of Popular 3D Printing." International Journal 1.

Abstract:

The unexpected appearance of 3D printing has caught many of technology analyst by surprise. In this paper we aim to provide a social context to the feedback loops that have generated this rapid evolution of technologies and skills involved in 3D printing, as well as and online communities related with 3D printing and the impact of this evolution on media an popular imaginary... and our near future.

Three Dimensional Printing: An Introduction for Information Professional

Marcoux, Julie, and Kenneth-Roy Bonin. "Three Dimensional Printing: An Introduction for Information Professionals." ICDS 2012, The Sixth International Conference on Digital Society. 2012.

Abstract:

Advanced by some as the next great emerging technology to enjoy overwhelming market penetration, three dimensional (3D) printing could have significant information implications, notwithstanding limited coverage in the information science literature. This review of complementary material from other sources provides the introductory definitions, technical descriptions and indications of future developments relevant to information professionals.

On the viability of the open source development model for the design of physical objects

de Bruijn, Erik, et al. "On the viability of the open source development model for the design of physical objects Lessons learned from the RepRap project." (2010).

Abstract:

While open source software development has been studied extensively, relatively little is known about the viability of the same development model for a physical object’s design. This thesis addresses this deficit by exploring the extent to which this model is viable for the development of physical objects. It starts with a review of the relevant literature on open source and user innovation communities followed by a case study and survey of the RepRap community. This community develops a digital fabrication system that can 3D print a large share of its own parts. This allows for a decentralized community to independently produce physical parts based on digital designs that are shared via the internet. Apart from improving the device, dedicated infrastructure was developed by user innovators. The survey reveals substantial adoption and development of 3D printer technology, comparable to the larger vendors in the industry. RepRap community members are spending between 145 and 182 full-time equivalents and have spent between 382,000 and 478,000 dollars on innovation alone. At the RepRap project’s 6 month doubling interval, it is entirely feasible that its adoption and disruptive levels of innovation will exceed that of the incumbent industry. Within the community there is a higher incidence in modifications of hardware than in software, and, surprisingly, hardware modifications are expected to be relatively easier for others to replicate. The level of collaboration is also higher for hardware than for software. Through Thingiverse, a web-based sharing platform originating from the RepRap project, 1,486 designs of physical objects in the last 6 months. Also, more than 10,000 objects were independently manufactured by its members’ machines. While already substantial, this level activity exhibits similar exponential growth characteristics. Many RepRap community members possess a fabrication capability that the average person does not have access to. While this does limit the present day generality of the case study findings, there are many reasons to expect a high likelihood of personal access to digital fabrication in the near future. The rapid development and adoption of increasingly affordable, yet more powerful and valuable fabrication technologies and the anti-rival logic of open design allow user-dominant collaborative development to have significant implications for the provisioning of goods in society. Finally, I provide a discussion of the implications and make suggestions for further research.

RepRap: The Replicating Rapid Prototyper: Maximizing Customizability by Breeding the Means of Production

Sells, Ed, Smith, Zach , Bailard, Sebastien, Bowyer, Adrian and Olliver, Vik , RepRap: The Replicating Rapid Prototyper: Maximizing Customizability by Breeding the Means of Production. HANDBOOK OF RESEARCH IN MASS CUSTOMIZATION AND PERSONALIZATION, Forthcoming. Available at SSRN: http://ssrn.com/abstract=1594475

Abstract:

This paper describes progress on RepRap, the replicating rapid prototyper. RepRap is a filament-deposition rapid prototying machine that has been designed to manufacture the majority of its own parts. All other parts of the machine are standard materials and components available everywhere in the world. RepRap is intended to maximize the customizability of both the products that it makes and also itself. It achieves this by several complementary mechanisms: it is intended for individual (as well as industrial) use, so its users may employ it to manufacture whatever they want; it can make copies of itself, and those copies can be customized; it is extremely low cost, and so ownership can be widespread; and finally it is open-source, so all its designs and software are available for modification. Prototype RepRap machines have been built and are described. These have made parts for themselves and each other, and this is depicted. The design principles and specifications of the machine are given. The paper concludes with a discussion of the possible impacts that the machine may have on personal manufacturing and product customization.

On the open design of tangible goods

Raasch, Christina, Cornelius Herstatt, and Kerstin Balka. "On the open design of tangible goods." R&d Management 39.4 (2009): 382-393.

Abstract:

Open source software development has received considerable scholarly attention, much of which is based on the presumption that the ‘open source model’ holds some lessons of broader applicability. Nonetheless, our knowledge of its deployment outside the software industry is very limited. This paper focuses on the open source development of tangible objects, the so-called open design. We propose a generalised definition of open source development. Drawing on 27 exploratory interviews and six comparative case studies selected from a pool of more than 75 projects, we analyse the workings of open design. The analysis reveals that open design is already being implemented in a substantial variety of projects with different organisational and institutional structures.

From open source in the digital to the physical world: a smooth transfer?

Nizar Abdelkafi, Thorsten Blecker, Christina Raasch, (2009) "From open source in the digital to the physical world: a smooth transfer?", Management Decision, Vol. 47 Iss: 10, pp.1610 - 1632

Abstract:

Purpose – The purpose of this paper is to investigate the transferability of the open source principles of product development from the realm of software to the realm of physical products.

Design/methodology/approach – Based on the inherent differences between software and physical products, a theoretical discussion of the challenges that face the implementation of open source principles in the physical world are provided. A multiple case study methodology is adopted to provide insights into the applicability of the open source concept in product development outside software.

Findings – Many of the challenges identified theoretically are actually encountered in practice. To cope with these challenges effectively, hardware design activities can be translated into software development tasks, using programmable hardware. When dealing with open source projects in the physical realm, it is useful to distinguish between projects driven by commercial firms and those driven by individuals, as each project type can impose different conditions on successful implementation.

Originality/value – Although much scholarly attention has been devoted to open source software, the issue of transferability of the identified principles to other industries has undergone little in-depth research. This paper provides a solid foundation for further investigation of this topic based on theory and empirical case examples. It derives recommendations for industrial experts wishing to benefit from the open source model in new product development.

Future craft: how digital media is transforming product design

Bonanni, Leonardo, Amanda Parkes, and Hiroshi Ishii. "Future craft: how digital media is transforming product design." CHI'08 extended abstracts on Human factors in computing systems. ACM, 2008.

Abstract:

The open and collective traditions of the interaction community have created new opportunities for product designers to engage in the social issues around industrial production. This paper introduces Future Craft, a design methodology which applies emerging digital tools and processes to product design toward new objects that are socially and environmentally sustainable. We present the results of teaching the Future Craft curriculum at the MIT Media Lab including principal themes of public, local and personal design, resources, assignments and student work. Novel ethnographic methods are discussed with relevance to informing the design of physical products. We aim to create a dialogue around these themes for the product design and HCI communities.

Promoting Tools that integrate LCA into the Product Design Process

Vera, José. "Promoting Tools that integrate LCA into the Product Design Process: a Case Study in Ontario." (2010).

Abstract:

Design decisions can greatly affect the environmental impact of a product. The European Commission estimated that eighty percent of the environmental impacts of a product are determined during its design phase. Life Cycle Assessment (LCA) is a method for determining the environmental impact of a product or service. LCA can be utilized during the product design phase in order to evaluate the environmental impact of different design decisions. Engineers can use the information provided by the LCA to make decisions that lead to a reduction of the overall environmental impact. This study examines different tools that integrate LCA with the product design process including SolidWorks Sustainability. An LCA was performed on a simulation of a regular non ecofriendly 3D printer and on eco-friendly simulations of similar 3D printers as a case study of the challenges involved in integrating LCA with the design process. Public policy recommendations for promoting these LCA tools in Ontario and Canada were made based on the case study.

DDM – An Approach Towards Sustainable Production?

Bertling, Jürgen, et al. "DDM–An Approach Towards Sustainable Production?." Young 35.32: 30.

Abstract:

Direct Digital Manufacturing (DDM) is often regarded as the future of manufacturing. Since the future will be governed by questions of sustainability (e. g. availability of resources, emission prevention and fair production standards) DDM has to be analysed and optimised with respect to this. In this paper we will address sustainability aspects regarding two distinct development directions in DDM: the replacement of industrially established processes by additive manufacturing and the FabLab movement as an example of paradigm shift in consumer-producer-relationship.

First Steps Towards Collaboratively Edited Design For Additive Manufacturing Knowledge

Doubrovski, E. L., J. C. Verlinden, and I. Horvath. "FIRST STEPS TOWARDS COLLABORATIVELY EDITED DESIGN FOR ADDITIVE MANUFACTURING KNOWLEDGE."

Abstract:

Despite the broad coverage concerning the technological challenges, little research has been performed on the methods that enable designers to deal with Additive Manufacturing. At present, the challenge is to generate Design for Additive Manufacturing knowledge which goes beyond traditional solutions and to ensure that this knowledge is complete, correct and up to date. This paper reports on the employment of a wiki environment to support open-ended knowledge management. We applied this solution in an undergraduate prototyping course focused on exploring visual properties using AM structures. The results of the 32 students encompass unexpected designs while the knowledge on the wiki encompassed i) AM processes, ii) procedures, iii) artifacts. This forces us to rethink what should constitute DfAM.

Towards cyclic fabrication systems for modular robotics and rapid manufacturing

Moses, Matt, Hiroshi Yamaguchi, and Gregory S. Chirikjian. "Towards cyclic fabrication systems for modular robotics and rapid manufacturing." Proceedings of robotics: science and systems. 2009.

Abstract:

A cyclic fabrication system (CFS) is a network of materials, tools, and manufacturing processes that can produce all or most of its constituent components. This paper proposes an architecture for a robotic CFS based on modular components. The proposed system is intended to self-replicate via producing necessary components for replica devices. Some design challenges unique to self-replicating machines are discussed. Results from several proof-of-principle experiments are presented, including a manipulator designed to handle and assemble modules of the same type it is constructed from, a DC brush motor fabricated largely from raw materials, and basic manufacturing tools made with a simple CFS.

Accelerating the Innovation Process with the Help of Open Source Prototyping Hardware

MERKEL, Andreas, Hendrik HOPF, and Egon MÜLLER. "ACCELERATING THE INNOVATION PROCESS WITH THE HELP OF OPEN SOURCE PROTOTYPING HARDWARE.

Abstract:

Open source prototyping hardware appears to be easy to modify, extendable by function modules and its solutions are well‐documented. Currently it is primarily used in domestic and scientific projects, but it seems to be perfect for the development of prototypes for companies, too. One resulting question, which is the focus of this research paper, is: to what extent can the use of open source prototyping hardware accelerates prototyping as one of the main parts of companies’ innovation processes? In our upcoming research, various methods such as workshops for industrial prototyping, questionnaires and product‐tests will be utilized. KEYWORDS: innovation process, prototyping, open source hardware, electrical toolkits

Rapid Manufacturing as a tool for agile manufacturing: application and implementation perspectives

Bateman, RICHARD J., and K. Cheng. "Rapid manufacturing as a tool for agile manufacturing: applications and implementation perspectives." International Journal (2006).

Abstract:

Manufacturing engineers and technologists around the globe are already well familiar with manufacturing methodologies and systems developments in the last part of the twentieth century. Many are probably also familiar with the current state of Rapid Prototyping (RP) technologies, especially in the areas of concept model making and prototype development. They may not however, be so familiar with the more recent developments of these technologies towards Rapid Manufacturing (RM) and the directions which the applications of RM technologies are taking for agile manufacturing purposes in particular. This paper critically reviews the various technologies currently available, outlines development trends in RM, discusses the approach, application and implementation perspectives by which these RM technologies are applied for increasing agility and responsiveness in manufacturing. Furthermore, the paper describes two case study examples to further illustrate the application scenarios in agile manufacturing before concluding remarks.

Universal Desktop Fabrication

Vilbrandt, Turlif, et al. "Universal desktop fabrication." Heterogeneous objects modelling and applications (2008): 259-284.

Abstract:

Advances in digital design and fabrication technologies are leading toward single fabrication systems capable of producing almost any complete functional object. We are proposing a new paradigm for manufacturing, which we call Universal Desktop Fabrication (UDF), and a framework for its development. UDF will be a coherent system of volumetric digital design software able to handle infinite complexity at any spatial resolution and compact, automated, multi-material digital fabrication hardware. This system aims to be inexpensive, simple, safe and intuitive to operate, open to user modification and experimentation, and capable of rapidly manufacturing almost any arbitrary, complete, high-quality, functional object. Through the broad accessibility and generality of digital technology, UDF will enable vastly more individuals to become innovators of technology, and will catalyze a shift from specialized mass production and global transportation of products to personal customization and point-of-use manufacturing. Likewise, the inherent accuracy and speed of digital computation will allow processes that significantly surpass the practical complexity of the current design and manufacturing systems. This transformation of manufacturing will allow for entirely new classes of human-made, peerproduced, micro-engineered objects, resulting in more dynamic and natural interactions with the world. We describe and illustrate our current results in UDF hardware and software, and describe future development directions.

The Materialization of Digital Information and the Digital Economy

Ratto, Matt, and Robert Ree. "The Materialization of Digital Information and the Digital Economy Knowledge Synthesis Report." (2010).

Abstract:

This report addresses an important and potentially far-reaching phenomenon emerging in digital media, namely: the increasing movement of previously digital resources adn techniques into the physical environment. A blurring of the 'divide between bits and atoms' is occurring that holds the potential to greatly transform current relations between companies and consumers and to redefine how both individuals and collectives participate in digital economies and also in larger cultural, social and political life.

Fluid Dynamics Analysis of Desktop-based Fused Deposition Modeling Rapid Prototyping

Roxas, Mark. Fluid Dynamics Analysis of Desktop-based Fused Deposition Modeling Rapid Prototyping. Diss. University of Toronto, 2008.

Abstract:

Recent improvements in the area of Fused Deposition Modelling have led to the creation of inexpensive desktop based Rapid Prototypers such as the Replicating Rapid-Prototyper (RepRap) allowing the individual the freedom to fabricate three dimensional parts of their own, however print resolutions of the parts are not on the same level as commercially based systems. It has been observed that adjusting the certain parameters on the polymer melt extruder such as the extruder nozzle diameter, nozzle angle, and liquefier length ultimately affects the extruded melt flow behaviour [17]. These parameters are important factors to consider for an improved design. This thesis presents the results of the computational and experimental work that shows the effect of taking the original specifications of the RepRap extruder and aims to show how reducing nozzle exit diameter and varying nozzle angle has resulting effects on the pressure drop and the flow behaviour of the melt. The results show that optimization of the flow rate can have significant effects on the extruded melt and it also shows limitations on how small the nozzle exit diameter can be before the resulting pressure drop becomes too large such that the motor cannot provide enough torque to drive the flow. Ultimately, the proposed redesign suggests that the RepRap’s extruder nozzle diameter can be decreased from 0.5mm to 0.3mm with a nozzle angle of 120 degrees which will decrease the diameter of the extruded melt contributing to better resolutions. The report further shows the consequences of further decreasing the diameter and nozzle angle and concludes with an experiment that observes the melt flow behaviour of the melt to ensure that PCL is a valid candidate material for Fused Deposition Modelling in Rapid Prototyping.

Open production Scientific Foundation for co-creative product realization

Wulfsberg, Jens Peter, Tobias Redlich, and Franz-Ludwig Bruhns. "Open production: scientific foundation for co-creative product realization." Production Engineering 5.2 (2011): 127-139.

Abstract:

Globalization and the use of technology call for an adaptation of value creation strategies. As the potential for rationalization and achieving flexibility within companies is to the greatest possible extent exhausted, approaches to the corporate reorganization of value creation are becoming increasingly important. In this process, the spread and further development of information and communication technology often provide the basis for a reorganization of cross-company value nets and lead to a redistribution of roles and tasks between the actors involved in value creation. While cooperative, decentralized and self-organizing value creation processes are in fact being promoted, the associated potential for development and production engineering is being underestimated and hence not implemented sufficiently. This contribution will introduce a value creation taxonomy and then, using its notion and structure, describe the emerging transformations in value creation on the basis of case studies. Finally an adequate framework for

Product Development in Open Design Communities A Process Perspective

Raasch, Christina. "Product Development In Open Design Communities: A Process Perspective." International Journal of Innovation and Technology Management 8.04 (2011): 557-575.

Abstract:

Open source (OS) has raised significant attention in industrial practice and in scholarly research as a new and successful mode of product development. This paper is among the first to study open source development processes outside their original context, the software industry. In particular, we investigate the development of tangible products in so-called open design projects. We study how open design projects address the challenges usually put forward in the literature as barriers to the open development of tangible products. The analysis rests on the comparative qualitative investigation of four cases from different industries. We find that, subject to certain contingencies, open design processes can be organized to resemble OSS development processes to a considerable degree. Some practices are established specifically to uphold OS principles in the open design context, while others starkly differ from those found in OSS development. Our discussion focusses on different aspects of modularity as well as the availability of lowcost tools.

Wire embedding 3D Printer

Bayless, Jacob, Mo Chen, and Bing Dai. "Wire embedding 3D printer." (2010).

Abstract:

The RepRap 3D printer is an open-source rapid prototyping machine capable of producing most of its own structural components. This printer can be built and run at a much lower price than a commercial 3D printer, and used to create copies of itself. Its first model, Darwin, was released online in 2008. It can print durable and accurate parts from thermoplastic materials, but it cannot currently print with electrically conductive materials. The Gada Prize, established in 2010 to advance the RepRap project, is a $80,000 grand prize and $20,000 interim prize that will be awarded to a machine like the RepRap which meets several additional specifications, including the ability to print conductors. The wire-embedding 3D printer project adds a wire-printing tool head, “SpoolHead”, to the RepRap Darwin model. The SpoolHead is a promising new approach to manufacturing hybrid wire-and-plastic parts, and an attempt to meet the conductive materials requirement of the Gada prize. This report documents the development and testing of the first SpoolHead prototype, a wire-printing mechanism that uses a servo-actuated mechanical pencil to insert metal wires into the heated surface of a printed thermoplastic part. The wires are then to be cut by a solenoid-actuated mechanism that shears the wire inside the main tube of the print head. Benchtop tests performed to validate the design philosophy of the SpoolHead gave positive results. The print head was then manufactured and tested on two designs proposed at the outset of the project, a rectangle and a spiral. The SpoolHead was able to print the spiral design to within the specified ±0.5 mm tolerances outlined at the beginning of the project. The printed rectangle was out of specification, with straightness errors of up to 0.8 mm and dimensions short by 1 mm of the design length. However, the errors responsible for this have been identified and can be easily resolved in future versions. It was found that the cutter design failed, requiring manual intervention in the cutting process. While alternative methods have been proposed to improve the cutter, a fully satis- factory solution remains to be found. Numerous recommendations are presented that outline how the future development of the SpoolHead should proceed, beginning with investigating replacing the cutter. Methods for future miniaturization of the device are presented, as well as plans for improved electronics and software.

Rapid casting of patterned vascular networks for perfusable engineered three-dimensional tissues

Bhatia, Sangeeta N., and Christopher S. Chen. "Rapid casting of patterned vascular networks for perfusable engineered three-dimensional tissues." (2012).

Abstract:

In the absence of perfusable vascular networks, three- dimensional (3D) engineered tissues densely populated with cells quickly develop a necrotic core1 . Yet the lack of a general approach to rapidly construct such networks remains a major challenge for 3D tissue culture2–4 . Here, we printed rigid 3D filament networks of carbohydrate glass, and used them as a cytocompatible sacrificial template in engineered tissues containing living cells to generate cylindrical networks that could be lined with endothelial cells and perfused with blood under high-pressure pulsatile flow. Because this simple vascular casting approach allows independent control of network geometry, endothelialization and extravascular tissue, it is compatible with a wide variety of cell types, synthetic and natural extracellular matrices, and crosslinking strategies. We also demonstrated that the perfused vascular channels sustained the metabolic function of primary rat hepatocytes in engineered tissue constructs that otherwise exhibited suppressed function in their core.

How Well Can They Cope With Geometric Complexity?

Pei, Eujin, R. Ian Campbell, and Deon de Beer. "Entry-level RP machines: how well can they cope with geometric complexity?." Assembly Automation 31.2 (2011): 153-160.

Abstract:

The literature review provides an overview of RP technologies, followed by a discussion on the different levels of complexity in objects. The paper continues with a discussion on the definition of entry level rapid prototyping, followed by a number of experiments to explore the limitations of an entry level RP system when fabricating complex models, and to compare the results obtained with those from a professional RP machine using standardised build parameters and the same ABS material.

Additive Manufacturing in South Africa Building on the Foundations

Campbell, R. I., D. J. De Beer, and Eujin Pei. "Additive manufacturing in South Africa: building on the foundations." Rapid Prototyping Journal 17.2 (2011): 156-162.

Abstract:

In a previous Rapid Prototyping Journal paper, the authors reviewed the first decade of Rapid Prototyping (RP) use within the Republic of South Africa (RSA). The paper analysed its strengths, weaknesses, opportunities and threats, and proposed a “road-map” for future development. Much has happened in the intervening years since that article was published and this paper seeks to update readers on the current situation in RSA. In particular, it reports the extensive development of research in the field of RP and Additive Manufacturing (AM).

Design, Fabrication, and Characterization of a Low-Cost Flexural Bearing Based 3D Printing Tool Head

Ramirez, Aaron Eduardo. Design, fabrication, and characterization of a low-cost flexural bearing based 3D printing tool head. Diss. Massachusetts Institute of Technology, 2010.

Abstract:

This thesis discusses the design, characterization and optimization of a low-cost additive rapid- prototyping tool head for a technology known as Fused Filament Fabrication for use in an educational curriculum. Building a 3D printer represents an excellent educational opportunity as it requires knowledge in electronics, mechanics, and thermal-fluids engineering; this particular design also includes a flexural bearing, introducing students to a new and important class of machine element. Polymer flow through the extruder is modeled as pipe flow with pressure drops using Bernoulli's equation with viscous losses; the model predicts that the pressure 1 required to extrude is proportional to , where d is the nozzle diameter. Three different extruder designs are considered; a piston-based design, an auger-based design, and a pinch-wheel design. The pinch wheel design best meets the functional requirements after comparing the designs based on factors such as complexity and controllability. Flexural bearings are selected to provide a preload against the polymer filament; HDPE was chosen to be the flexure material after considering factors such as water-jet machinability and yield stress to elastic modulus ratio. Thermal imaging shows that the temperature profile along the heater barrel is not uniform, with the largest variation being 80±2.8*C in large part due to errors in heater wire distribution during assembly. An exponential relationship is observed between the force required to extrude versus the temperature of the heater barrel with the force required to extrude dropping to between 1 and 2N in the range of 200 to 240*C. This data suggests trade-offs between maintaining a reasonable extruding pressure and maintaining good build resolution and speed. A discussion of the low- cost rapid prototyping cycle follows, as well as instructions for assembly and use of the extruder. The paper ends with several suggestions to improve extruder performance and a list of ideas for bringing the extruder costs down.

PV Junction Box

Waterproofing 3D Prints (and also making them look super-cool) with Epoxy Clay

Neil's Log Book

Abstract:

It’s pretty hard to get a watertight object out of our Makerbot Thing-O-Matic. The walls of printed objects are pretty solid, but unexpectedly porous; even a thick block printed with 100% infill will allow water to penetrate it due to errors around the edges and imperfectly fused strands of plastic. If you want to make a hollow object waterproof you’re going to have to do some post-processing.

Inverter and PV System Technology

Solarpraxis 2012 and Sunbeam 2012

Abstract:

"Inverter and PV System Technology” takes a close look at the electrical components of the PV system and its interactions, gives an overview of market conditions and presents the latest technical developments. Corporate portraits of international companies round off this comprehensive industry guide on PV system technology.

AN3432 Application Note, How to choose a bypass diode for a silicon panel junction box

STMicroelectronics 2011

Abstract:

Today, the main technologies used in solar panel are polycrystalline and mono crystalline silicon solar cells. When one solar cell of the panel is shaded while the others are illuminated, a hot spot could appear and leads to the shaded cell destruction. The bypass diode is an efficient solution to eliminate the “hot spot” and maintain the current delivery. The Schottky diode is a cost effective candidate. Its VRRM, VF/IR trade off need to fit the panel and junction box characteristics. This document gives a method to select the most appropriate diode versus the panel characteristics.

A Simple, Low-Cost Conductive Composite Material for 3D Printing of Electronic Sensors

Leigh, Simon J., et al. "A simple, low-cost conductive composite material for 3D printing of electronic sensors." PLoS One 7.11 (2012): e49365.

Abstract:

3D printing technology can produce complex objects directly from computer aided digital designs. The technology has traditionally been used by large companies to produce fit and form concept prototypes (‘rapid prototyping’) before production. In recent years however there has been a move to adopt the technology as full-scale manufacturing solution. The advent of low-cost, desktop 3D printers such as the RepRap and Fab@Home has meant a wider user base are now able to have access to desktop manufacturing platforms enabling them to produce highly customised products for personal use and sale. This uptake in usage has been coupled with a demand for printing technology and materials able to print functional elements such as electronic sensors. Here we present formulation of a simple conductive thermoplastic composite we term ‘carbomorph’ and demonstrate how it can be used in an unmodified low-cost 3D printer to print electronic sensors able to sense mechanical flexing and capacitance changes. We show how this capability can be used to produce custom sensing devices and user interface devices along with printed objects with embedded sensing capability. This advance in low-cost 3D printing with offer a new paradigm in the 3D printing field with printed sensors and electronics embedded inside 3D printed objects in a single build process without requiring complex or expensive materials incorporating additives such as carbon nanotubes.

PV Laminates and Installation

Application Guidelines for Photovoltaic Laminates

Soligent

Abstract:

This document is a desktop reference for UNI‐SOLAR® customers to support the development, design, construction, and estimation of rooftop photovoltaic projects involving UNI‐SOLAR photovoltaic laminates. The design notes and examples, labor case studies for estimations, energy modeling guidelines, and other material in this document are intended to be used as a reference for sales professionals, engineers, estimators, and construction personnel working on UNI‐SOLAR projects. The guidelines and information contained herein support, but do not replace or supersede, the specifications of the UNI‐SOLAR installation guides. The installation guides should be considered the specifications to which a UNI‐SOLAR installation must adhere for the UNI‐SOLAR Limited Product and Performance Warranty to apply.

Building a System

Affordable Solar

Abstract: Don't know what to look for or what components you'll need? Search through our articles here in the Building a System section to find out what you'll need to build and assemble a system that's right for you.

UV Protection / Lifetime Assessment

The effect of photo-oxidative degradation on fracture in ABS pipe resins

P. Davis, B. E. Tiganis, and L. S. Burn, “The effect of photo-oxidative degradation on fracture in ABS pipe resins,” Polymer Degradation and Stability, vol. 84, no. 2, pp. 233–242, May 200

Abstract:

This work investigates ultraviolet (UV) degradation and its influence on fracture failure in acrylonitrile–butadiene–styrene (ABS) resins. Preliminary chemiluminescence assessment of coupon specimens indicates that degradation is restricted to the specimen surface, with a relatively rapid depletion of residual stabiliser compared to the bulk of the specimen. Fourier transform infra-red spectral analysis indicates that this surface-specific degradation forms photoproducts with the distortion of absorbance bands (corresponding to the trans CC unsaturation (vinyl) in polybutadiene (PB), and the 1,2-butadiene terminal vinyl C–H band), indicating bond unsaturation. These changes in chemical structure are attributed to cross-linking and chain scission in the PB phase. It is proposed that surface degradation after UV exposure promotes brittle behaviour and may therefore influence the failure mechanism of ABS pressure pipes under static loading. The effect of UV exposure in coupon specimens is compared to that of surface notching, and plane-strain fracture toughness tests are used to obtain an empirical relationship between exposure time and “equivalent” notch depth. By assuming that this relationship is independent of specimen geometry (i.e. degradation is restricted to the surface), a methodology for estimating the lifetime of UV-exposed ABS pipes is proposed. An analysis of DN100 Class 15 ABS pipes predicts that a transition to brittle fracture failure occurs after 137 years. However, it is recommended that the influence of pipe wall thickness on degradation kinetics be quantified.

The Outdoor Performance of Plastic Materials Used as Cable Accessories

R. J. T. Clabbum, R. J. Penneck, and C. J. Swinmurn, “The Outdoor Performance of Plastic Materials Used as Cable Accessories,” IEEE Transactions on Power Apparatus and Systems, vol. PAS-92, no. 6, pp. 1833 –1842, Nov. 1973.

Abstract:

This paper shows how plastics materials may be affected by exposure to the outdoor environment. The possible effects of ultra violet light, atmospheric oxygen, moisture, gaseous and solid pollution are discussed in detail. Data obtained from extensive natural and accelerated weathering on a variety of materials demonstrates the practical significance of this information and shows that outdoor performance can vary dramatically between polymers and that even minor changes in the chemical constitution of either the polymer or the incorporated additives can have very significant and often detrimental effects.

Plastic photovoltaic devices

Sariciftci, Niyazi Serdar. "Plastic photovoltaic devices." Materials today 7.9 (2004): 36-40.

Abstract:

The development of organic, polymer-based photovoltaic elements has introduced the possibility of obtaining cheap and easy-to-produce energy from light. Photoinduced electron transfer from donor-type semiconducting polymers onto acceptor-type polymers or molecules, such as C60, is the basic phenomenon utilized in these photovoltaic devices. This process mimics the early photo-effects in natural photosynthesis. The polymeric semiconductors combine the photoelectrical properties of inorganic semiconductors with the large-scale, low-cost technology of polymeric ‘plastic’ materials. To date, devices with power conversion efficiencies of ∼5% have been reported. Several companies and research institutions are focusing on this field now, making power conversion efficiencies up to 8-10% highly likely in the near future.

Design and implementation of a continuous improvement framework for an organic photovoltaic panels manufactur

Colaci, Gregorio. Design and implementation of a continuous improvement framework for an organic photovoltaic panels manufacturer. Diss. Massachusetts Institute of Technology, 2011.

Abstract:

The MIT MEng Team worked at Konarka Technologies, the world leader organic photovoltaic panels (OPV) manufacturer, on several improvement projects. The concentration was on operations improvement as well as production information tracking and analysis. This thesis report, however, focuses primarily on the implementation of a continuous improvement culture. Tools to implement the SS methodology, such as 5S Audit, Kaizen board and Kanban board, were provided, and operators were trained. A layout improvement solution was developed, and a plan for implementation recommended. The new layout was designed to increase visual control of the processes and to reduce movement of material by 85%. Each phase of the project went through review and discussion to encourage operator involvement in order to develop a continuous improvement culture.

Integration of green roof and solar photovoltaic systems

Hui, Sam CM, and Miss SC Chan. "Integration of green roof and solar photovoltaic systems."

Abstract:

Green roof and solar photovoltaic (PV) systems are two technologies that could contribute to sustainable building development and reduction of greenhouse gas emissions. When they are combined together on the building roof, it can enhance their functions and effectiveness by cooling and shading effects. This paper explains the major findings of a research to study the benefits of integrating green roof and solar PV systems. The important factors affecting the interactions between the two systems are assessed. The thermal and energy effects are analysed by theoretical models, experiments and field studies. A hypothetical case study to retrofit the roof of an existing building in Hong Kong with such integration is carried out to evaluate the practical design issues. The experimental results showed a positive influence for this integration: green roof surface and soil temperatures are reduced from the shading and higher power output of PV panel is achieved from the cooling. The findings of year-round building energy simulation using EnergyPlus for a low rise commercial building indicated that the energy consumption for air conditioning of the integrated system is slightly lower than the stand-alone system and the PV system on integrated approach generates 8.3% more electricity than the stand-a-lone option. The extent of the benefits depends on the system design and how to determine the optimum arrangement for a particular building site.

Zeus Technical White Paper Weathering of Plastics

Zeus Industrial Products

Abstract:

We are all no doubt aware of the main effect of ultraviolet (UV) radiation on ourselves – how many of us have ended up with a red nose after a day out in the sun? Our skin is not the only organic structure to suffer; even polymers will be affected to some degree by exposure to sunlight and ultraviolet radiation. The main problem is that so many parameters affect the level of exposure, and there are several ways of providing resistance to the effects.

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