Team:Cambridge-JIC/Design

CAMBRIDGE-JIC

Problem statement

Design criteria

A list of design criteria for our hardware.

Potential Solutions

We have designed a low-cost, open-source microscope built mainly from off-the-shelf and 3D-printable components. Anyone with access to our designs and a 3D printer should will be able to build one for themselves. Comparisons were made of OpenScope to that of a conventional microscope:

Commercial fluorescence microscopes score 19 points.

Our OpenScope design scores 24 points on this scale.

Design Implications

OpenScope has huge potential to increase accessibility to microscopy to areas out with the iGEM project:

  • Education: OpenScope could be used to introduce secondary-school students to fluorescence microscopy. Its low cost means it is well within a school’s budget, and is in fact cheaper than most school microscopes. Printing and assembling the microscope itself could also be an educational experience.

  • Research: Most research labs are able to afford a commercial fluorescence microscope, but budget constraints mean there is usually one for the entire lab (with a specialised room) and time needs to be booked on it. This restricts its use significantly. Having several OpenScopes alongside it would enable researchers to quickly image new samples, or perform things like time-lapse imaging. OpenScope could also be integrated into other equipment like fume hoods or incubators.

  • On the move: OpenScope is light weight and can be battery powered. This makes it ideal for fieldwork where a conventional microscope would be impossible to carry. Its ability to be remote controlled means it can also be left in remote areas and be accessed at any point.

  • Developing Countries: Its low cost makes it accessible to labs in developing countries, and its ease of assembly and service allows labs to use it without having to rely on spare parts and technical support from a distant company.

Environmental Impact

The bulk of the microscope is polylactic acid (PLA). PLA is a fully biodegradable polymer, derived from sugarcane. Its thermoplastic nature means it has the potential for being recycled into many products at the end of the microscope's life1. The other main components are the printed circuit boards used in the Raspberry Pi and Arduino. These contain silicon chips and other components such as lead, cadmium and mercury. These can be hazardous in the environment if not recycled or disposed of safely 2.

This gives a brief overview of environmental considerations associated with OpenScope. However, we wished to gain a more in depth understanding of environmental impacts, both for us and others using the microscope. A full life cycle analysis was carried out using using the Eco Audit tool on the CES Selector Program3. The program allows for the energy use in MJ and carbon emissions in kg to be calculated for the product over its lifetime. The Eco Audit tool calculates these by taking into consideration the materials and material processing used, the use of the product, the power consumption (calculations for power consumption are given here) and any transportation involved.

Assumptions

  • Materials and Processing: For each part of the microscope only the main materials, making up the majority of the part, were considered. Materials and manufacturing processes were collated from online and are accurate to the best of our knowledge. There is not an option on the tool for 3D printing as a materials process and so from the chassis said to be made by polymer moulding, the most similar process.

  • Transportation: All parts for the microscope are being sourced locally, many parts can be bought in bulk and it would assume the only transportation would be by light goods vehicles, travelling across England.

  • Use:We assumed the average person would use our microscope 4 days a week and use it for 2 hours each of these days. It was also assumed that the microscope would have a lifetime of 1 year

Social Impact

OpenScope has the potential to become widespread and greatly expand the accessibility of microscopy. The cost of microscopes will no longer be so much of a barrier to synthetic biology research. Other tools can be developed which incorporate OpenScope, leading to other useful equipment being developed. The open-source licensing strategy we’ve used means anyone can develop our hardware and software, leading to more equipment being developed based on OpenScope and some of our changes being introduced in other commercial initiatives as well.

Useful Software

Below is a list of software programs that we have found useful for developing open-source hardware, supplemented with other commonly used programs:

  1. OpenSCAD – a free, open-source, parametric CAD platform used to design 3D objects for printing (available from here)

  2. Tracker – a free, open-source, video analysis and modelling tool. Used to track moving objects in videos and extract data (available from here)

  3. Cura 3D – a free, open-source 3D printer interface from Ultimaker. Used to control printer settings (available from here)

  4. Fiji - a free, open-source image processing and analysis platform. Particularly useful for microscopy (available from here)

  5. Inkscape – a free, open-source vector graphics package. Extremely useful for 2D design followed by linear extrusion (available from here)

  6. DesignSpark – a free electronics design software for PCB prototyping. Has an online library of over 80,000 parts (available from here)

  7. Scribus – a free, open-source graphics software. Particularly useful for publishing (available from here)

  8. Python – a free, open-source, programming language that allowed us to put together software quickly

  9. Nginx – A FOSS lightweight web server on top of which we built our web interfaces.

  10. OpenCV – A FOSS released under a BSD license that provides a library for image processing software (available from here)

For a detailed list of free, open-source software programs available, look here.

References

[1] Yutaka Tokiwa; Buenaventurada P. Calabia; Charles U. Ugwu; Seiichi Aiba, "Biodegradability of Plastics", 2009, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2769161/.

[2] Lucy McAllister, "The Human and Environmental Effects of E-Waste", 2015, http://www.prb.org/Publications/Articles/2013/e-waste.aspx/.