SHEL2 - Abolfazl Ghaderi

Problem

Headphones are an increasingly popular piece of technology. However, unlike other devices, the main focus is mostly on developing technical parts. As a result, they are large, which makes them less convenient to travel with.

How can we design a pair of headphones with better Portability?

Should not sacrifice the convenience and the comfort of the headband

Should not sacrifice the quality of the sound (by reducing the size)

Should not affect the honesty of the headphones’ functionality

Inspiration

Ideation

Introducing SHEL 2.0 SHEL 2.0

SHEL 2.0 is a pair of foldable headphones designed based on the Kangaroo tail’s mechanism. This has resulted in a loose headband that can freely change in form.

To achieve this particular design, 23 plastic parts are put together by a piece of fabric passing through them. When pulled tightly, these plastic pieces fixate in their position, and when loosened, they can have free movements.

User Experience

A servo motor is used to pull the inner band. The servo starts pulling when the headphone is switched-on, as the band rolls along an axis connected to the servo motor.

The size of the servo should be very small to fit inside the can alongside other components, as this case should have a horizontal movement. This way the user can adjust the headphone according to his/her head size. So the particular Tower Pro MG 90D was selected as it is a substantially small servo with metal gears that can stall 2.4kg per centimeter.

Parts

The Big Challenge

If the servo motor is turned off after turning the headphones on, it would easily turn back, and the headband would lose its tightened position. On the other hand, if it stays on, the continuous resistance to keep the headband fixed would result in staling of the servo and can damage the gears, motors, and battery.

To tackle this issue, a ratchet wheel is inserted at the end of the servo’s axis. This ratchet rotates freely in a clockwise direction, which tightened the band. However, when the headphones are switched on, a pawl locks the counter-clockwise direction.

For the version one