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Engineering for the Circular Economy


Project Duration

2015 – Today

Project Competenses

  • Concept Development
  • Design for Additive Manufacturing
  • Topology Optimisation
  • Design for Assembly
  • Circular Design
  • Design Thinking

Project Background

Design firm Van der Kallen has developed a circular furniture line. By using modular components a stool can be disassembled and recycled into a bench or a table. One of the crucial components of this concept is a metal welded connector, used to join the various wooden beams. Downside of this metal connector is that recycling metal is very energy intensive.

The Objective

Van der Kallen asked Fransiscó to create a more sustainable alternative to the metal connector. As a case study a stool was developed that:

  • Replaces the metal connector with an additive manufactured plastic connector
  • Minimises the amount of material used
  • Is simple to assemble
  • Uses a minimum amount of parts
  • Has a more than sufficient load carrying capacity
  • As an overall concept fits into the circular economy philosphy of Van der Kallen.
  • The original Circle stool by Van der Kallen used welded metal corner pieces. 

  • Various use cases have been defined prior to topology optimisation.

  • Topology Optimisation was used to define an effecient geometry. Material is only placed in locations where it contributes to strength and stiffness.

    The Result

    Topology Optimisation was used to create optimised connector that fulfilled the requirements while using the minimal amount of material. The first prototype iterations were 3D printed with biodegradable plastic.

    Later iterations use SLS polyamide using white EcoPowder, as shown on the pictures on the left. The stool has been showcased at the 2016 Dutch Design Week in Eindhoven.

    More Info

    For more information about concept development and circular design please contact Fransiscó at: