c-HRC Grasshopper plug-in Complex Hiprafter Construction – simple fabrication of complex wooden forms

A plug-in developed for the 3D-modelling software Rhinoceros at the Institute for Digital Economy in the Construction and Wood Industries (IdBH) makes it easy to manufacture flowing architectural forms from wood. It brings the ability to produce any number of complex geometric shapes to a wide market.


  • Lead school(s) School of Architecture, Wood and Civil Engineering
  • Institute Institute for Digital Construction and Wood Industry IDBH
  • Research unit Institute for Digital Construction and Wood Industry IDBH
  • Duration 20.04.2020 - 30.04.2023
  • Project management Miro Bannwart
  • Head of project Miro Bannwart
  • Partner Treppenbau.ch
  • Keywords Rhino, Grasshopper, Parametrics, Wood, Panels, Architecture, Free form, Geometry, Wood architecture, Digital, Digital manufacturing, Gravitational Pavilion, Climbing wall


Free-form projects using wood are often made of complex, individual components that are difficult to manufacture, generating high production costs. Thus, the production of such complex forms needs to be simplified. In order to do this, it would have to be possible at the digital project design stage to transform the complex basic shape into an individual component that is easy to produce. The challenge lies in achieving this simplification.


The aim is to develop computer-based methods that enable complex wooden forms to be manufactured easily. To achieve this goal, the complex wooden free forms are broken down into highly simplified individual components. These can then be used to build a complex wooden structure from individual beams.

More specifically, a user-friendly Grasshopper plug-in called Sawfish is to be developed for the 3D-modelling software Rhinoceros. The new plug-in will generate simplified triangle-based production geometries on complex free-form areas which can be cut with either the CNC or a hand-held circular saw. All angles and lengths required are displayed visually for manual cutting.


In 2017, Miro Bannwart created the Gravitational Pavilion as part of the fabrication module on the bachelor’s degree programme. The wooden dome was assembled with support from industry partners Krüsi Maschinenbau AG and Treppenbau.ch AG. The production geometry for the Gravitational Pavilion was created in 2017 using the visual programming plug-in Sawfish.


The code, written in the C# programming language, has since been published on the Food4Rhino and GitHub platforms as a user-friendly Grasshopper plug-in called Sawfish. This makes the calculation of the individual components for wooden free forms of any desired complexity accessible to a wide market and offers an easier option for planning and manufacturing free-forms from wood.