Portals: CASE

Texture Changing Handles that Improve Cyclists' Safety

Simple and intuitive user interaction is the dogma for interaction design, yet in our physical world new products often sacrifice simplicity in the name of new functionality. Portals is our concept of integrating meaning and functionality to our everyday objects within their natural flow of interaction to help users navigate through our physical space. It alerts users with relevant information hidden behind the doors at appropriate times through shape change without adding extra interaction with the artifact. We developed prototypes in the context of hospitals and automobiles: TARZ mediates privacy for the patient while informing doctors of vital information and CASE improves cyclists' safety.

CASE is a pneumatically-driven texture changing handle that aims to reduce collision between bicyclists and automobile passengers opening doors to exit their vehicle. The pulsing indicates the direction from which the bicyclist is approaching as well as their proximity via pulsing speed [i.e. faster means closer]. Another application is an alternative to GPS that does not require bicyclists to take eyes off the road. A subtle shape change in the handles suggest not only the direction he should go to reach a destination [pulsing in the left handle for a left turn, in the right for a right turn], but also his proximity to the correct turn [increased heartbeat rhythm]. For both applications, users are able to receive a valuable piece of information while performing the natural course of action to achieve their task. Because of the sheet form factor, CASE can easily be added on to existing products.

MAS.834 Tangible Interfaces | 2014
MIT Media Lab
Instructor: Hiroshi Ishii

Programming Languages / Hardware Arduino

CollaboratorsXavi Benavides, Paola Mariselli, Ana Torres, and Luke Vink

Contextualizing the two spaces: traveler and inhabitor

The driver/car passenger [traveler] can learn about dangers outside the car [i.e. biker as inhabator] before existing the car

Prototyping Processes

Pneumatic actuation involving rubber silicone and rubber sheets were explored for texture changes.

Mold for silicone sample
Testing different materials and parameters [thicknesses, stencils, adhesives]
Prototyping the handle cover constructed of mylar stencil sandwiched in between thin rubber sheets
Sample of stencil patterns - the bottom left stencil worked best

CASE Setup

Arduino digitally controls the pneumatic pump

Earlier Design Process

Concept Development

Before narrowing down to TARZ and CASE, we explored various mappings for physical space and interaction that we encounter on a daily basis.

Shapes as Media to Inform Meaning and Function

We conceptualized shape changing: TARZ takes after stiffness and form changing aspects, and CASE takes after textural change.


Making a door easy or difficult to open. Slows down the user (i.e. TARZ door resistance)


Nested affordance to describe conditions behind the door. Effective for quick interaction (i.e. CASE car door handle)


Can be highly controlled for detailed mappings. User avoids interaction (i.e. TARZ patient sleeping mode)

Quick User Testing

We made quick and dirty samples of the new textures on the regular door handles to test user reactions. These are three of our samples. All users indicated noticeable changes in the texture of the handles for all of our samples. Most liked the soft texture on the ends of the image and expressed discomfort and surprise for the middle porcupine prototype.