Submitted by M.L. R. Grove on Tue, 07/04/2020 - 09:40
The University of Cambridge Centre for Natural Material Innovation and University of Queensland Folded Structures Lab have developed a design for a reusable face shield which folds from a single flat sheet of clear plastic material into a face shield for health workers treating Covid-19 patients.
The design uses a “curved-crease origami” approach to transform any clear sheet material into a face shield which, when folded along the curved crease and combined with a strap, transforms from a flat sheet into a three-dimensional shape which conforms to the wearer’s head, and provides a barrier from splashes and sprays of bodily fluids from Covid-19 patients.
The current significant shortage of adequate PPE for health workers in the UK and worldwide is exacerbated by challenges in producing and delivering manufactured goods when large portions of the supply chain are compromised by social distancing measures or worker illness, which result in both labour and materials supply shortages.
The design developed by the team, called “HappyShield”, exploits the mechanical behaviour of curved crease origami forms to allow for production of face shields using any clear sheet material which may be available in a given location. The design allows for the use of a variety of manufacturing methods depending on availability, ranging from manual methods requiring nothing more than a pair of scissors, a ruler, and a ballpoint pen, to highly industrialised methods using die-cutting machines which are typically used to manufacture food packing cartons and other sheet material products. Such die cutting machines could be retooled to produce as many as 50,000 face shields a day per facility, based on similar research conducted at MIT.
The key to the HappyShield design is its geometry: the locations and precise curvatures of folding curves developed by the team allow for the transformation of a single piece of sheet material into three connected elements: a face shield portion, a visor, and a forehead rest. These three elements support each other to form a stiff three-dimensional shape which comfortably distributes pressure on to the wearer’s forehead while rigidly positioning the face shield at the necessary distance from the wearer’s face to provide space for other required PPE, such as goggles and a respirator.
Because the designs consist only of a sheet of semi-rigid plastic material and a removable, disposable strap, they can be easily cleaned and disinfected for reuse, helping to reduce the enormous demand for new disposable face shields.
The designs have received very positive feedback from ICU doctors at Addenbrooke’s hospital, and are currently under review for official clinical approval.
The team envisions the approach being taken up by manufacturers and DIY manufacturers worldwide using locally available raw materials and tools, and has posted instructions and cutting and folding templates for the shields on its website.
While the team anticipates that the PPE needs of the UK and other wealthy countries are likely to be met relatively soon given the recent wave of maker and manufacturer innovation as a response to the PPE shortage caused by the Covid-19 pandemic, less wealthy regions which are likely to be hardest hit by the virus may continue to struggle to produce the required PPE.
The simplicity and ability of the HappyShield design to be manufactured using a wide range of plastic sheet materials and tools make it well-suited for adaptation by makers and manufacturers in these areas, which are likely to face even more extreme supply chain disruptions.
Consistent with the team’s international focus, instructions for the manufacturing of HappyShield are currently being translated into as many as 10 languages, with the goal being to jumpstart production by as many makers and manufacturers globally as possible.
Readers can download instructions and view video for how to make their own HappyShield at home using only materials found in a typical home here.