Measuring arms
OnyxAceMeasuring arms
with 3D scanners
Onyx SkylineAce Skylinewith 3D scanners
The Bangkok Mahadthai Uthit Bridge (Thailand), more usually known as the Weeping Bridge, its sculptures and stucco, were recently part of an ambitious heritage preservation program using 3D scanning.
Built by the Italian sculptor Vittorio Novi, who was inspired by the small bridges of the Roman Antiquity, the Weeping Bridge spans the Manahak canal since 1914. It is considered to be Bangkok’s most Italian bridge. This simple and classic structure, with its European-style pillars, features unusual bas-reliefs which are very different from traditional Thai motifs. The pillars depict sorrowing figures mourning the loss of Rama V, who had passed away 4 years before the bridge construction. Being sculpted from photographs Vittorio Novi, they are decorated with weeping vestal-like women accompanied by a child.
A 3D laser scanner Zephyr II, integrated with a 7 axis 3,5 m Ace measuring arm, put on a telescopic tripod, were used for this study.
The arm is temperature regulated so as it runs outside and keeps measurement accuracy regardless of temperature or humidity conditions.
Due to the telescopic tripod and its mobility, the process was achieved in record time. The device succeeded scanning 20 meters of the bridge and height starting from 1 m (bas-relief) to 2,50 m (pillars) in a single evening.
Zephyr II high speed scanning (250 000 points /s) and wide laser line (100 mm) also provided process fastness. Zephyr II keeps a 15 µ accuracy independent from ambient light, and its resolution ensures a high level of precision for every sculpture restitution.
Performed for heritage purposes, this study was useful for artistic purposes, used to reproduce and carve stuccos and pillars in polystyrene.
The survey project, performed by GeoWorks (Kreon’s official partner in Thailand), is a cooperation work of Bangkok Metropolitan Administration, Silpakorn University and Kasetsart University.
