Process

Max Ingersoll and Nina Cragg

 We wanted to make a piece of furniture that could easily transform between two states, a table and a chair. It was essential to us that the design only require the user to perform one action to transform the chair. To do this, we would need a mechanism that would allow for expansion in three dimensions. The obvious mechanism that stood out to us was the Hoberman Sphere, which is essentially a pantograph curved into the shape of a sphere. We liked its simple and elegant design, and we thought that it would be possible to make it strong enough to support the weight of a person. Once we had our mechanism, we had to decide on the design of our chair and table.  

 For the chair aspect of our design, we were inspired by the comfort of the papasan chair. Even though we were making a transforming piece of furniture, it was very important to us to not sacrifice the comfort of the user. For the table aspect of our design, we were inspired by the triangular, meshing pieces of the The Fletcher Capstan Table. We also really liked how elegant and easy it was for the user to change it into its different forms.

 We went through many iterations. First, to begin to understand the Hoberman Mechanism and its properties, we performed different studies, creating different 2D and 3D examples of the mechanism of different sizes and thicknesses using wood. From these studies, we learned a few key things that impacted our design. We learned that we should use as few segments as possible in order to maximize the strength of our model. This is because the wobble in the structure mainly came from the joints that connect the segments, which had to be loose enough to allow rotation. When we had a model with more segments, the wobble from the joints was greatly increased because the number of joints were increased. To minimize this, we decided on a design that had eight segments, instead of our original twenty segments. We also used bolts, which had significantly less wobble than our 3D printed rivets.

It was difficult to visualize and modify the design using traditional 3D modeling software, and we wanted to be able to easily change a few aspects of our model, such as: the length, width, thickness, and number of segments, and how open the model was. So instead of statically modeling the chair, we created a parametric model of our design in Grasshopper, an extension for Rhinoceros 3D. This allowed us to open and close the model, as well as modify its dimensions all with the adjustment of sliders. This model was integral to our design process, because it allowed us to rapidly make changes to the design, and see many issues with certain designs before physically prototyping them.  After many concepts, we arrived on the floral design, with curved smaller segments supporting the chair and table, and larger "petal" pieces  coming together to form the surface of the table.

Brief

Max Ingersoll and Nina Cragg

 

 People who live in small spaces often find it difficult to find space for their furniture. The Hoberman Chair is piece of furniture that transforms between two phases, a lounge chair and a space-efficient table. The chair uses the three-dimensional scissor mechanism invented by Chuck Hoberman, and popularized in the Hoberman Sphere, to expand and contract in three dimensions. The elegant and mesmerizing motion of the petal shaped pieces gives the user the impression of a flower blooming.

The table is formed when the outer segments meet together in the closed phase, and the piece sits parallel to the ground. In this phase, the legs are also oriented with a support that holds the table upright.

The chair is formed when the mechanism is opened, achieved by pulling outwards on the table. In this stage, the segments open up into a ring. The piece is then tipped onto its side, and rests on the edge of two of the four legs. Elastic string is weaved in the area inside the ring, forming a seat for the user.