Timber, or wood, one of the pre-industrial era’s most favoured building materials is currently experiencing a resurgence in use; fuelled in part by developments in CNC technologies, digital fabrication advancement and automation. Robotic fabrication techniques in timber construction have improved the way wood is used in construction, with the efficiency and flexibility of robotic automation key drivers for this resurgence.
In the past timber fabrication was a manual and labour intensive process however the computational design and digital fabrication options available in 2020 mean timber is fast becoming a more attractive construction material when compared to fossil fuel-based alternatives. Timber being a renewable resource, carbon positive and a natural CO2 storage can also satisfy a global mood for green initiatives with pro-active climate positive construction contributing to resurging interest in timber fabrication.
Science, architecture and fabrication were previously viewed as unrelated fields, but as research from the University of Stuttgart, Germany in collaboration with Müllerblaustein Holzbau GmbH, Landesgartenschau Schwäbisch Gmünd 2014 GmbH, the forest administration of Baden-Württemberg (ForstBW) and KUKA Robotics GmbH has shown these fields can be connected. Their “Robotics in Timber Construction” research project has shown that newly developed timber construction offers not only innovative architectural possibilities; it is also highly resource efficient, with the load bearing plate structure being just 50mm thin.
Industrial manipulators, in this case robots, were used to construct an interlocking timber structured building – the Landesgartenschau Exhibition Hall. Designed with 243 individual segments of plywood made from beech wood using a robotic off-site fabrication method. The higher degree of kinematic freedom and fabrication flexibility offered by industrial robots when compared to process-specific CNC (Computer Numerically Controlled) machines was an essential requirement for the production of such complex and individual geometries.
In 2019, the team at the university went on to replicate the project, using a 14 axes robotic timber-manufacturing platform to create the BUGA Wood Pavilion, on the Summer Island of the Bundesgartenschau. The flexibility of the industrial robot allowed for the integration of all pre-fabrication steps of the pavilion’s segments within one compact manufacturing unit. This robot, like the one used in the Exhibition Hall, is capable of drilling wood across multiple planes and was used to create the panels. If this process were to be completed manually, it would require a huge amount of time but for the Hall it took just three weeks and for the Pavilion a mere 10 days.
According to the project team, "One of the most important challenges and innovations is the robotic fabrication of the 7,600 individual finger joints, which, through their interlocking connection, are the main reason for the building’s structural stability,”
The building is “the first to have its primary structure entirely made of robotically prefabricated beech plywood plate.”
As seen with these 2 major projects industrial robots have become an atypical addition to the field of CNC machining. They are not limited to specific fabrication processes and have been shown to maximize yield, increase uptime and reduce production costs. The development, fabrication and construction of these projects has shown that existing design and fabrication strategies can be reinterpreted or reappropriated resulting in new and novel architectural systems which are beneficial to the environment as well as to the construction industry.
For more resources on about this project and robotics in timber construction see:
BUGA a wood pavilion robotically manufactured by Timberbiz
Robotic fabrication in timber construction by ScienceDaily
Adaptive Automation Strategies for Robotic Prefabrication of Parametrized Mass Timber Building Components by O. D. Kriega and O. Langa (ISARC 2019)
Robotically Fabricated Wood Plate Morphologies by Tobias Schwinn, Oliver David Krieg, Achim Menges
Potentials of Robotic Fabrication in Wood Construction: Elastically bent timber sheets with robotically fabricated finger joints by Oliver David Krieg, Achim Menges
Landesgartenschau Exhibition Hall is a plywood pavilion made by robots by Anna Winston (dezeen)
Robotic Fabrication in Timber Construction by Prof. J. Knippers, Prof. V. Schwieger, Prof. A. Menges