Difficulty: Intermediate
Time: 3 days
Introduction
This tutorial demonstrates how to program a thin sheet of Nitinol into a passive reconfigurable tactile display at Braille resolution. The fabrication process can be adapted to create various pixel designs of different shapes and sizes depending on the application. In addition to the tutorial, at the bottom you will find a simple method to serendipitously explore the design and interaction space using paper, before engaging in the fabrication process.
Pre-requisite and background topics
Prior to starting the tutorial, you can try to familiarise yourself with the following topics:
Materials and equipment required
Electric Furnace (to heat above 550ºC)
Water bath
Steel wire (0.25mm diameter)
Foam sheet / Soft base
Tweezers
Instructions
Design an array of U-shaped flaps to be laser cut on Nitinol
Bend the flaps by pushing them out on foam sheet
Constrain the flaps in the bend position by inserting a small wire between the flap and the sheet. One method is to cut small wires of 3cm, bend them into a U shape and insert them between the open flap and the base sheet.
Place this fixture in a furnace at 500ºC for 30 minutes
Quench it in a water bath
Place the fixture again in the furnace at 550ºC for 48 hours
Let the fixture cool inside the furnace
Remove the wires
Test
Variations and things to try
Before engaging with Nitinol, explore the solution space by mimicking the tactile effect with card paper.
Alternative pixel shapes
Alternative pixel sizes
Alternative pixel orientations
Alternative pixel patterns
Size of the display
Applications
Post-requisite topics and Going beyond
Read the associated academic paper
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