The idea behind the iteration was to form an assembly line type system to roll cuvettes through different testing stations. The supports contained ball bearings to help cuvettes roll.

Design thinking process:

(Figure depicts the mathematical design of curve that is printed for testing)

• Mount curves that resembled rails on to a hollow cylinder
• Make stops along the curve to imitate test stations
• Have a cuvette holder with a ball bearing

 

 

 

( Image on the left is a CAD of the Helix rail and on the right is a prototype cuvette holder)

Advantages:

•  Capable of storing large amount of cuvettes
• Takes up comparatively less space
• Uses gravity to push cuvettes down hence mechanical complexity would be low.

Why the design failed:

• The Helix needed to be 3d printed in small parts that were hard to join
• it was hard to mount a curved piece
• Testing stations were hard to model 
• Cuvettes even with ball bearings did not slide due to PLA on PLA friction

(Image: 3D printed prototype of the failed helix)