Virtual try-on of Additively Manufactured Orthosis via Augmented Reality
Authors: Menezes De Souza Melo Gustavo , Feng Chenyan , Reich Stefan , Henrich Schleifenbaum Johannes 
Published: July 2023

Virtual try-on applications came to market not too long ago to be a
supportive part of online shopping, allowing consumers to try clothes or
accessories on before making the purchase. This kind of applications proved
to be highly useful in decreasing return rates of the products. More and
more online markets are using AR technology to improve the shopping
experience of consumers in fashion field. However, AR technology should be
able to do more than making products more attractive, especially in the
medical field. Finding an orthosis product that both satisfies the medical
requirement and has an appealing design has always been hard for patients
with physical inconvenience, especially during corona time. Traditionally,
consumers first need to make a mould in a physical orthosis store, then they
have to make multiple trips to the store to keep giving suggestions to the
staff of how the orthosis needs to be adjusted, until they are satisfied
with the final product. This process takes a long time, since orthosis are
usually hand-made, and the adjustment process could be frustrating for the
orthosis consumers. To go to the physical store, orthosis consumers have to
tolerate the time spent on the way, limited choices of design to try on in
each store, and the risk of corona infection due to close contact with
people over there. The producers also have to cover for the wear-out
samples, the time it takes for multiple discussion on improvements, as well
as taking the risk of the patients not liking the design after production. A
virtual orthosis try-on application is the best solution to satisfy both
sides, it bridges the gap between orthosis consumers and the producers. This
application would make individualization of orthosis products easier, saving
the time of communications and possible miscommunications. Moreover, this
app make the digitalized production line to be more appealing and
trustworthy to orthosis consumers. The orthosis model is automatically
generated with the 3D scan of the consumers' leg, then the consumers use
this application to try on different designs and colours, and the final
product can be additive manufactured after they made their choice. In this
way, consumers do not need to go to the physical store anymore, saving much
time and effort. The try-on application was first designed and assigned
functions that it is supposed to achieve using design thinking methods, then
designed and build with game engine Unity, which has many ready-to-use
packages, together with the tracking technology from the Vuforia engine.
Both Marker-less and Marker-based tracking were tried out during the
development. Marker-based tracking were chosen in the end for a more
satisfying end-product. Finally, a preference test was made for a better
version of this application with a controlled group.A marker-based Android
application was successfully made after many trails. Consumers only need to
place two QR codes on both sides of their thighs, then they can view the
augmented orthosis from different angles on the camera of a personal Android
device, choose the design patterns and colours of the orthosis model by
simple clicks on the user interface, and select the model that attracts them
the most.