Introduction
The text provided here are excerpts from the paper referenced below. In addition to the text listed here, and the videos, please read through part 4 & 5 of the attached paper – the case study on this method.
[1] S. Oberloier and J. M. Pearce, “General Design Procedure for Free and Open-Source Hardware for Scientific Equipment,” Designs, vol. 2, no. 1, p. 2, Mar. 2018, doi: 10.3390/designs2010002.
Literature Review & Proof of Concept
A literature review must be undertaken before a new open hardware device is to be designed. This literature review should ensure that there have not been other open-source designs for the same device as well as detail how similar devices are fabricated for commercial applications. In both cases the fundamental concepts that are targeted are the physical steps that the device must perform as well as determining the metrics of success. Cooperation is important to thriving FOSH.
If a literature review reveals that a solution already exists, build off of what has been done, adding improvements or refinements.
In conjunction with this step, it may be useful to generate an as-simple-as-possible proof of concept. If there are even small signs of success, the design may be worth pursuing. However, if the proof of concept does not work, it may be wise to rethink the approach.
Design, Involving the Following Design Principles
Use of Only Free and Open-Source Tool Chain
Use free and open-source software design tools where possible in the initial design (e.g., open-source CAD packages such as OpenSCAD, FreeCAD, or Blender). For example, with an open-source customizer it is possible for even novices to make customizable designs. FOSS should be used for all software whenever possible. Finally, the fabrication equipment used to make the targeted device should run free and open-source firmware and should when possible be FOSH itself (e.g., a RepRap 3D printer). If that is not feasible, then low-cost and/or widely-used software packages and hardware should be favored. This is to ensure the widest possible accessibility of your designs for remixing by others.
Using FOSH and FOSS should fall in naturally with the scientific method as an important factor in the scientific method is repeatability. However, if an experiment uses high-priced proprietary tools, this is a barrier to others trying to replicate the results. By using open-source design methodologies for hardware, costs can be minimized, allowing for ease of replication and verification.
Minimize Complexity
In order to support maintenance, upgrading, repair, and end of life disassembly and recycling, attempt to minimize the number and type of parts (e.g., use all the same type of fastener) and the complexity of the tool overall. Minimize dissimilar materials when unnecessary and reduce the part count. It should be noted, however, that the individual parts when digitally manufactured can be as complex as the tools (e.g., 3D printers) allow for, with no penalty.
Designers must consider that the users of their instruments may not be engineers or specifically skilled in instrument manufacturing. Therefore, complexity should also be reduced in manufacturing techniques as well as applied theories.
Minimize Material Consumption
By reducing the amount of material used, the environmental impact is minimized as the processing and transportation embodied energy are all reduced by the reduced use of material. This can be done by eliminating non-functional bulk to designs, and, in 3D printed designs, minimizing infill percentage to fulfill mechanical requirements. In addition, material minimization reduces overall economic costs from reduced processing time as well as material costs.
Maximize Components that Can Be Digitally Manufactured and Distributed
The use of distributed digital manufacturing using widespread and accessible tools such as the RepRap 3D printer and open PCB mills help to reduce both the environmental impact as well as reduce the economic costs of production. Lead times can also be reduced, as well as improving maintainability.
Create Parametric Designs
By making parametric designs rather than solving a specific case, all future cases can also be solved while enabling future users to alter the core variables to make the device useful for them. For example, a simple 3D printable syringe pump resulted in thousands of downloads and customizations, creating millions of dollars of value for the scientific community in the first year of its release. The syringe pumps were used in multi-material 3D printers, wax printing of paper-based microfluidics , and as a fluid handling robot for chemical and biological experiments. In addition, the original design was improved and ported from a Raspberry Pi environment to an Arduino environment for in-lab control.
The creation of parametric tools allows a large degree of flexibility to the user. Properly parametrized 3D model designs will allow users to alter critical dimensions for their purposes. In some cases, it will also allow models to be reformatted such that they could be manufactured with a wide and unforeseeable range of tools.
Off-the-Shelf Parts
All customized parts are designed to be digitally manufactured, but often times less expensive components can be found that are mass manufactured (e.g., pipes, tubes, screws, etc.). These should be sourced so they are as widely available as possible throughout the world. Using off the shelf parts allow research labs to stock a minimum of parts, which are widely used. This, once again, reduces the lead time, which speeds up research.
Validation
In order for the FOSH tool to be used in the scientific community, it must be validated using a clear and transparent procedure and have a low-cost, effective method of calibration. Again, whenever possible, one should use other digitally manufactured open hardware tools and FOSS to complete the validation and calibration.
Proper Documentation
Documentation must actively assist a non-specialist with recreating the hardware. The Open Source Hardware Association (OSHWA) has extensive guidelines for properly documenting and releasing open-source designs. In summary, the guidelines are:
- Share design files in the most universal type.
- Include a fully detailed bill of materials, including prices and sourcing information.
- If software is involved, make sure the code is clear and understandable to a layman.
- Include many photos such that nothing is obscured; these can be used as a reference while manufacturing.
- In the methods section, the entire manufacturing process must be detailed, as these are instructions for users to replicate the design.
- Share on many file hosting sites (see step 5 below), but also be sure to specify a license. This gives users information on what fair use of the design constitutes.
Share Aggressively
Open-source hardware can be at a disadvantage when competing with proprietary technology, because proprietary technology is sold through conventional channels and typically will have a marketing budget to pay for advertising. FOSH can be sold and marketed through this model as well, but in some cases this is not appropriate. In order for FOSH to proliferate, designs must be shared aggressively just to raise awareness of the existence of the option. All of the documentation for a project can be shared on the Open Science Framework, which is set up to take any type of file and handle large datasets. Software can be shared on sites like GitHub or SourceForge, and should include proper documentation on the inner workings of the code, as well as a brief summary. The 3D designs can be shared on sites set up by government scientific funders like the NIH 3D Print Exchange or open-source companies like Ultimaker’s YouMagine or MyMiniFactory as well as other repositories. Circuit designs can be shared on sites like the Open Circuit Institute.
Designers should consider spreading designs to as many hosting sites as possible, as this will only increase exposure. Regardless of the site, it is important to engage with the community, building personal rapport. Building a reputation for intelligence, reliability, and helpfulness will bolster confidence in your designs and increase usage.
