A Pop-up Chair
MISSION STATEMENT
The Chair Project is the term project for the last of the sequence of four required Structures courses in the curriculum of the University of Waterloo School of Architecture.
The project requires the design, construction and structural analysis of a folding or take-apart wooden chair for a client of student’s choice.
PROBLEM SPACE
Identifying our clients
Due to our background of Asian culture, we set our view on the limited per-capita residential space in Asia. Especially in metropolises like Tokyo, the extremely high population density results in more than one generations living together in an apartment. Therefore people always prefer room-saving and functional furniture. Here are two space-saving examples
Project goal
Design a chair that can save living space and improves the quality of life for a family.
DESIGN
Our creation process subdivides itself into three tiers: prototype, evaluation, and construction.
During our prototype stage, we had a brainstorm to find a notion method to meet the user's requirement. Eventually, we got inspired by the popup book master, Waldo Hunt, and determined the concept of “Popup Chair”.
Then in the evaluation stage, users’ feedbacks and structural analysis contributed to the crucial improvement in the design of the chair. The rigorous first two stages ensured the success of construction.
PROTOTYPE
Low fidelity prototype
We started with extensive exploration to gather possibilities. The key method is creating a minimal version first and then optimize it according to test and feedbacks again and again.
Reference: Cut and Fold Techniques for Pop-Up Designs by Paul Jackson
We have introduced techniques for making pop-ups from one sheet of card.
High fidelity prototype
The feasibility of constructing the chair is rather crucial in this stage. We built different models for various tests, and calculate the physical property of the chair in the worst case to guarantee the safety of users.
1:1 model
We first made a 1:1 model with foam board to review the design, which helped us to realize some problems on the ratio and dimension. Then we built another rough 1:1 model with wood and this time we apply piano hinges in joints. It’s of great importance when gathering authentic feedbacks.
EVALUATION
Structural analysis
The weight of the chair, the center of gravity, overturning forces
Reactions, tipping forces
Load take-down/frame analysis
Lateral stability and racking
Beam analyses: actual shear and bending stresses, and best approximation of
Deflection
Users’feedback
In the final review for chair design, we invited the reviewers to try our 1:1 rough wooden model, and received plenty of valuable suggestions:
Make the holder bigger to allow the forearm to get through.
Lower the chair 5cm to achieve better ergonomic performance.
Cut some area off to reduce the weight and to be more portable.
Strengthen the side chair with extra support for psychologically stable though it’s strong enough for a 70kg person