ZipStrip

Chris Precht, master student at TU Vienna and founder of prechteck combined a GH definition I developed for modelling paperstrip geometries with the principle of ZipShape, developed by Christoph Schindler, to model these beautiful prototypes, as part of his thesis: Images (c) by Chris Precht.

Carlo Borer's Sculpture '422' Completed

Pictures (c) by Carlo Borer.

In previous posts I reported about the design and fabrication process of this piece of art.

Fabrication of Carlo Borer's Sculpture

The artist Carlo Borer and a 1:4 scale model of the sculpture.


Carlo rolling a chrome steel sheet at Senn AG


... verifying a curvature radius.

Grasshopper tools have been used in the design and fabrication process of the sculpture. Pictures (c) by Paul F. Talman.

New Evolutions in ZipShape

Christoph Schindler, co-founder of schindlersalmerón, develops the principle of ZipShape since 2007, in order to build curved elements from cnc-manufactured plain material without molds.


An element consists of two differently slotted panels that only interlock if bent to the desired curvature.


A grasshopper definition worked out during a workshop at the CITA Copenhagen shows the dependency between slot geometry and global curvature.


The newest development allows the fabrication of developable twisted surfaces.


This principle has been applied to a sculpture produced and tested at the Bern University of Applied Sciences in Biel.

Developable Surface Optimization

The artist Carlo Borer asked me to implement tailored developable surface modelling tools for rhino.


Using Grasshopper together with the evolutionary algorithm solver Galapagos, an optimization routine for lofted surface strips towards developable surfaces has been implemented.


Gaussian curvature of original and optimized surface. For developable surfaces, the gaussian curvature is zero.


Carlo Borer: 401, 2009.

Parametric Paperstrip

This parametric model represents the geometry of a twisted straight paperstrip. Length, width, and twist are adjustable.


Some example strips. By definition these surfaces are developable.


The paperstrip as generative element. (c) by Michael Hensel and Achim Menges, Arch+ 188 p.20.


Download the definition here. Another interesting approach has been done by Daniel Piker.

Developable Surface Modelling

A grasshopper definition for developable surface strips. Download here. Mårten Nettelbladt gives a nice description of developable surface types.

Developable Surfaces in Gehry's Architecture

Gehry's east river guggenheim project in NYC. The use of flexible sheet material like paper in physical models generates developable geometries.

Dennis Shelden, CTO at gt, describes in his phd thesis several ways to compute developable surfaces. Fig. (c) by Dennis Shelden.


Museum MARTa in Herford, Germany. Most of the roof surfaces are developable. Geometric modelling of the roof construction has been done by Jess Maertterer. Further discription on his page.

Exploring the PQ Strip

Helmut Pottmann and his colleagues form the Geometric Modeling and Industrial Geometry resarch unit at TU Vienna describe the concept of the PQ strip in this paper. The strip consists of planar quad faces. Fig. (c) by H. Pottmann et al.



By lofting the edges, a developable surface is generated. Developable surfaces can be flattened or unrolled without distortion.



Download a grasshopper definition of the PQ strip here.