Everyday gadgets contain an impressive range of technology; very high quality sensors, cameras, and microprocessors are now incredibly cheap - making it possible to build lab equipment very cheaply. Doing this would make a big difference in developing countries, as it enables better screening for diseases like malaria or TB, and makes it possible to study science in the lab as well as in theory. The biggest challenge with this approach is often mounting the different parts together: good quality mechanical mounts are very expensive. We will measure and develop micro-mechanical properties of printed plastic parts, and understand how the structure of the prints affects their strength and flexibility. This will allow us to improve the way parts are printed, and create stronger, better mechanisms using only low-cost plastic. Together with readily available parts, we will then design, build and test a number of optical lab instruments, including microscopes, spectrometers, and sample preparation equipment.
The 3D printers that are now found all over the world work by extruding plastic through a hot nozzle, and drawing shapes by moving the nozzle over a print bed. 3D objects can be made by stacking multiple layers on top of each other. This layer-by-layer approach means that the exact path taken by the nozzle as it prints the object strongly affects the mechanical properties of the part, and it is this effect that we particularly want to understand and control. Once we have fully understood the relationship between the path taken by the nozzle and the properties of the final part, we will be able to create much better toolpaths to make objects that are stronger, weaker, stiffer or more flexible - and to balance these properties as we need them in different parts of a design.
This new printing process will allow us to create parts that move very precisely, which is a crucial part of building precision instruments such as microscopes, spectrometers, and more. These instruments can be produced anywhere with a printer - including in many of the least developed countries in the world. Our partners in Tanzania will pilot this, and work with local clinics, universities and schools to explore how these better, cheaper instruments can help improve education and healthcare.