3D scanning experts from Physical Digital® recently took part in an historic project in conjunction with the Royal Institution and the creators of the Magic Box exhibition facility.
Reverse Engineering the Davy Lamp
We were honoured to be asked to 3D scan the prototype Davy Lamp to gain highly-accurate measurements and produce a 3D model of the lamp through reverse engineering.
The Magic Box is an innovative means of extending the accessibility of museum exhibits to a larger audience. At first sight it appears to be a traditional display cabinet but has a touch screen with various options for visitors to view and reference the virtual exhibits inside. There will be an image of the 3D model (similar to a hologram) of each exhibit, created by the design engineers at Physical Digital from the highly-accurate data captured by our applications engineers through non-contact 3D scanning. For each piece, there will be supporting material for viewers to access, such as drawings, reference books, diaries or research papers. The idea is that visitors can learn more about each exhibit, and manipulate the model and supporting material within the case.
3D scanning using GOM Triple Scan system for high-accuracy data
Physical Digital’s highly-trained applications engineers used the globally-recognised GOM non-contact 3D scanning systems in order to capture the high-accuracy data required to create a 3D Computer Aided Design (CAD) model of the Davy Lamp. In strictly-controlled conditions at the Royal Institution, the lamp was 3D scanned on a measuring table on which had been placed a number of markers.
Physical Digital 3D scanning the prototype Davy Lamp at the Royal Institution
Images were captured using our GOM Triple Scan system of the markers and lamp, within a cuboid shaped area of 320mm x 240mm x 200 mm. The resolution of the 3D scanning was 64 microns, which means that the minimum distance between any captured points was 0.064mm, resulting in a very high resolution image.
Reverse engineering to recreate the Davy Lamp
Once the data was captured within the GOM scanning systems, it was processed by our design engineers and through the technique of reverse engineering a CAD model was gradually and carefully built up to replicate the historic artefact. Surfaces were created using vertical and horizontal cross-sections through the scan data. Our design engineers then created 3D curves through intersections at equal intervals after measuring the mesh structure from the scan data, then weaved splines to resemble the original model. The final CAD model is a combination of free form CAD for the gauze chimney and parametric solids at the base of the lamp.
The final CAD model is a combination of freeform and parametric solids
View a video of the 3D scanning process at the Royal Institution or visit our Youtube channel: Physical Digital Limited.
History of Davy’s Safety Lamp
Humphry Davy was born in Penzance in 1778 and attended Truro Grammar School before becoming an apothecary’s apprentice. In 1798 he moved to Bristol to work at Thomas Beddoes’s Pneumatic Institution where he discovered the physiological effects of nitrous oxide (laughing gas). In 1802 he became Professor of Chemistry at the Royal Institution, which had been established in 1799, where he established the Institution’s excellent reputation for lectures and scientific research.
In 1812 he was the first person to be knighted by the Prince Regent after King George III was declared mad. He left the Royal Institution in 1812 following his marriage to a wealthy heiress, touring the continent between 1813 and 1815 (when he took Michael Faraday as his assistant).
On his return to England he invented a form of the miners’ safety lamp. After a number of serious explosions in North east coal mines due to pockets of flammable gas known as ‘firedamp’ Davy was asked by the Rector of Bishopswearmouth near Sunderland to investigate a way of taking light into coal mines safely.
Between October and December 1815, Davy developed a number of prototypes, the simplest of which was a basic lamp with a wire gauze chimney enclosing the flame. The holes allow light to pass through but the gauze metal absorbs the heat and prevents an explosion as the flame is not sufficient to heat the flammable gas. The lamp was successfully tested in Hebburn colliery in January 1816 and quickly went into production with an immediate dramatic effect of lowering the number of fatalities of coal miners. It also increased coal production as it allowed miners to access deeper seams of coal.
Sir Humphry watched the 3D scanning process with great interest
Davy was made President of the Royal Society but after resigning from this post due to ill health he travelled again to the continent. In 1825 he received a silver-gilt cup from Tsar Alexander I of Russia, in recognition of his invention of the miners’ safety lamp a decade before. He died in Geneva on 29th May 1829 and is buried in the city’s Cimitière Plainpalais.
As well as the prototype Davy Lamp, our skilled 3D scanning engineers captured the data from the S Chimney Lamp, Faraday’s Induction Ring and the world’s first electric generator, also invented by Faraday. In addition, our engineers 3D scanned the priceless Tsar’s Cup in order to provide an accurate record of this hugely important piece.
The Cup presented to Humphry Davy in 1825 by Tsar Alexander I of Russia
Our high-accuracy 3D scanning services provide vital data for a wide range of projects, from historic artefacts such as this project, to automotive and aerospace projects, marine, medical and power generation works. To discuss how we can improve your project, contact us or call 01483 750200.