“Out of the Cabinets” is a research project carried out through a partnership between LiDA and CIUHCT – Interuniversity Centre for the History of Science and Technology of the University of Lisbon, which aims to develop functional replicas, 3D printed, historical scientific instruments from the 16th to 18th centuries, kept in national museums. Allowing access to the way these artefacts work gives the general public a deeper insight into the knowledge they contain.

The project started with the development of a functional model of Oughtred’s Circles of Proportion, developed around 1630 by the mathematician William Oughtred, an artefact that allows solving questions of arithmetic, geometry and astronomy, which was the first instrument using sliding parts to perform logarithmic calculations, like the most common slide rules used until 1970. Nowadays, copies of circular slide rules are extremely rare, with only seven known originals in the world, one of which is kept at the Museu Nacional de História Natural e da Ciência de Lisboa (MUHNAC).

During the project, several full-scale models were developed by a multidisciplinary team, with researchers in the areas of design, history of science and museum pedagogy. These models were tested in sessions of the MUHNAC educational service.

The results achieved demonstrate that the use of 3D printed models allows an easier and deeper understanding of the concepts underlying the objects on display, which for reasons of preservation and rarity cannot be touched by visitors.

Fused filament fabrication proved to be suitable for producing functional replicas, allowing a user experience similar to the original objects both from the point of view of their manipulation and their mathematical rigour. The development of the Oughtred Proportion Circles model paved the way for the use of this technology in the reproduction of other scientific instruments, thus investigating how this technology can be used for a more inclusive and diversified approach to the existing contents in science museums.

The development of this first object was supported by FCT – Fundação para a Ciência e Tecnologia under the Programa Verão com Ciência  2021 and by the British Embassy in Lisbon, within the scope of the development of the exhibition “The intimacy of numbers: Stafford’s amazing instrument in Lisbon”, where the original specimen kept at MUNHAC was exhibited, between September 16 and November 15, 2021.

In June 2022, the development of a second scientific instrument kept at MUNHAC began, a multipurpose pocket quadrant from 1573, which is not only the oldest scientific instrument in the MUNHAC collection but also one of the most valuable, since it is a piece made by Ieremias Arscenius in Louvain at the most famous workshop for mathematical and astronomical instruments in Europe at the time. This quadrant astrolabe incorporates a universal sundial and allows you to perform the same calculations as an astrolabe. With it, it is possible to measure heights and distances, determine the nocturnal or diurnal time, and calculate the sunrise and sunset times and those of other stars, among many other functions.

In order to guarantee a user experience more adequate to the museum’s public, who have different expectations, background knowledge and objectives from the original users of the 16th century, the artefacts are redesigned to allow a curiosity-driven, fluid, rigorous and similar use to the original objects.

The state of development of this Quadrant model already allows for its rigorous operation and ease of printing. The model is currently being tested by the MUNHAC educational service in an attempt to identify adjustments arising from its use by the general public.