Fast Cardboard Prototyping

“All models are wrong, but some are useful.”

– George Box

Designers in companies such as Nintendo use low-fidelity prototyping. Designer Kazuyuki Motoyama explains that the only way to actually know what a Miiverse would feel like was to hold it. That’s when he built this prototype out of cardboard. (Image credit: Nintendo)
When the end result is a physical product, you can use a wide range of materials to build mock-ups for testing. You can use rough materials, such as paper, cardboard, clay, or foam, and you can also repurpose existing objects you find around you in order to build physical models.The purpose of a physical model is to bring an intangible idea, or two-dimensional sketch, into a physical, three-dimensional plane. This allows for much better testing with users, and it can spark discussions about the form factor of the solution.

Cardboard prototyping is a common low-fidelity method to prototype and test physical objects and environments that are part of a service experience – for example, the interior of a shop environment, a ticket machine, furniture, devices and smaller props, and so on. The prototypes are built quickly, using cheap paper and cardboard mostly. Other equally easy-to-use materials like foam core, plasticine, or duct tape often complement the mix of materials.

Depending on the scope, the prototypes can be small-scale, actual size, or even bigger than life. To further explore and validate core functionality and the role of these objects cardboard prototyping is often used in conjunction with or as part of walkthrough approaches.

The most important part of cardboard prototyping is the process of prototyping itself. It helps to concretize the initial concept and explore its details, strengths, and weaknesses. A great way to start is to build many smaller scale versions before switching to full size, for the simple reason of speed.

Step-by-step guide

PREPARATION

1. Choose a User & an Operator: Who should test this cardboard prototype? One or more classmates sould test the prototype. The Operator simulates the functioning of the prototype, it should be one or more members of the team that build it.

2. Review scope and clarify prototyping questions:

  • What do you want to learn from this process?
  • Do you want to test the whole or just a part of the object?
  • Which part (literally) are you most interested in?
  • What are the tasks that you expect the user to do there?

3. Brainstorm Sketches and Diagrams

  • Use sketches to illustrate your ideas, even the simplest and crudest of sketches can easily achieve that. Sketch simple illustrations of your concepts so that they don’t exist only in your mind, hence allowing you to share these with your team-mates for further discussion and ideation.
  • You can also sketch diagrams, flow charts and mind maps in order to illustrate a system, process, or the structure of your ideas. You can sketch the various touch points that affect a user’s journey.

4. Build the prototype:

  • Use cardboard paper and tape to build the objects/environments/process/interface or the parts thereof you have chosen to focus on. If the object is interactive, build everything you need to act out any activities.

USE/RESEARCH

  1. ‍Test the prototype: Now conduct your test. Ask the user to perform a selected task. As the user starts to use the interface or carefully uses the object (i.e., handling it, pressing buttons, typing on keyboards, pulling handles, etc.), the operators react and simulate the reaction of the object or environment by manipulating, replacing, or adding parts. Iterate until the user has completed the task or failed.
  2. Keep a list of bugs, insights, and ideas, and review issues: Make sure that during the whole test the observers record their observations, and create a list of the issues that you discover. After each testing session take a few moments to reflect on what worked, what didn’t work, and what you would like to change or try next. Briefly discuss the issues you discovered and prioritize them.
  3. Revise your prototype : Are there any changes you can or should make right now? Remember that changes to cardboard prototypes can be made very easily and quickly. Do them now.

Method notes

  • Silent operators: The operators are usually silent. Ask them to refrain from explaining how the prototype should work. The rule of thumb is: if the device or computer would not say/print/bleep it, the operators should not either.
  • How to build: Start by building the basic forms (e.g., the body of a vending machine or the body of a convertible). Then add some of the moving parts. Moving parts can either be roughly built or simply be added or replaced during the simulation to cater for a certain functionality (e.g., the robot arm of the vending machine or the convertible top for the car). Finally, add paper prototypes of software/interface elements (e.g., displays, keyboards, control lamps).
  • Use what you have: Cardboard prototyping can get you carried away. People start prototyping everything just because it is fun. Use what you have.