2.2 Sketching Haptic Interactions


The initial concept for this module comes for this type of toy, where posture/structure can be relaxed. I found it valuable to explore what if a device can loose its structural and mechanical qualities?

Slacker 01

Internal parts have wire (dental floss) attached and when collectively pulled, they compress and solidify. The actuator is a muscle wire kit from Miga. It provides quite a lot of force over 1.5 cm of travel. It is silent and has a very organic feel. I also added a manual grip to activate it manually.

Slacker 02

I made a second iteration after the muscle wire actuator broke down. I reused the casing and the floating parts. Here you can see the broken actuator. The shape-memory alloy shrinks ~4% when heated. It was quite tedious to adjust all the dental floss wire equally, as they stretch over time. Having a unbalanced pull reduce the clutching effect.

At this time, I also built various options to control the muscle wire, to avoid overheating and possibly try to have some level of position control. I opted for a dual mode circuit: manual control with a button press, and computer-controlled via the Arduino board.

Slacker 03 (final)

In this third and last iteration, I used an accelerometer to trigger the pull. This way I there is no need for an UI. Shacking strongly 6-7 times will engage the unit, and the loose and shaky feeling disappears. It takes about 3-5 seconds to reset the unit, as the muscle wire has to cool down to return to its regular elongated state.


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