Switch-Pitch toy example

Grasshopper Kangaroo
1

I made an example of how to simulate the mechanism of the Hoberman ‘Switch Pitch’ toy in Kangaroo.
switchpitch_example.gh (38.9 KB)

It is made up of 12 bars meeting at the corners of a cube and connected by revolute joints (achieved in Kangaroo by making a pair of shared points along the hinge axis for each pair of connected rigid bodies).
In the toy there is a set of bevel gears at each node, which ensures all 3 connected elements fold evenly. This is achieved in Kangaroo with an EqualAngle goal.

Some references on this mechanism:

https://www.researchgate.net/publication/245513848_Mobility_and_Geometric_Analysis_of_the_Hoberman_Switch-Pitch_Ball_and_Its_Variant

http://www2.eng.cam.ac.uk/~sdg/preprint/IASSSwitchPitch.pdf

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2

@DanielPiker WOW. Very well done. Thank you for posting!