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GENERATIVE DESIGN CHAIR

This project explores the intersection of generative design and powder bed fusion through the creation of a lightweight, high-stiffness chair frame. Generative design utilizes algorithms to explore solutions to a defined set of criteria.


Using Fusion 360’s Generative Design feature, I defined preserve geometries, areas to be kept in the design, obstacle geometries, areas where material should not be generated, and provided the the direction and magnitudes of forces applied to the preserve geometries.


The outcomes of generative design modeling are often organic looking stuctures that would be very difficult or impossible to create using traditional methods of manufacturing. Powder bed fusion works especially well to create these organic, irregular geometries from generative design because it does not require any support material and can print parts in any orientation.


Model Photos

Chair model out of printer
Model straight out of powder printer
Chair model photo – back
Model cleaned of powder
Chair model photo – back
Model after painting:
Chair model photo – back angleChair model photo – frontChair model photo – top

Load Cases and Boundary Conditions

Applying proper load cases was essential to ensuring that the generative chair works structurally. Generative design is highly sensitive to the location of applied forces and to the placement of structural constraints, so careful reasoning was necessary.


Determining Cases

  • Vertical load on the seat: 3600 ounceforce* (200 lbs) on all four seat posts, representing a seated person
  • Backrest load: 1600 ounceforce* (100 lbs) horizontal (inclined 20 degree up) load to account for leaning

*Safety factor of 2 was used.

These values produce realistic stress conditions that guide the generative tool toward functional results.


Placement of Structural Constraints

The obstacle geometry ended up shaping the design the most. Throughout my process, I kept adding more obstacles, reducing the area where material could be generated. This helped give me a level of control over the generated designs and shape the chair to my liking.


Obstacles filled the area above the seat, where one would sit as well as below the seat/between the four legs. A ground was added so the chair would rest flat on the ground.


Later on, I added walls all around the the preserve geometry to constrain the chair to a smaller footprint.

Load cases applied in Fusion 360
Applied load cases
Obstacle geometry used to constrain generative design
Obstacle geometry
Resulting generative design after constraints
Obstacle geometry walls

Fusion Renders

Fusion render – front angleFusion render – backFusion render – sideFusion render – back angleFusion render – frontFusion render – top

Interactive CAD Model