A Flipo Flip toy can roll for multiple turns even though its shape is not circular. Investigate how its motion depends on parameters such as geometry and the initial release conditions.

Background reading from IYPT reference kit

*This Square Can Roll Like a Ball (youtube, The Action Lab, 30.08.2020), https://youtu.be/eZM0WtB3UX8

TYPT Supplementary References

basic

Amin Rezaeezadeh; Motion of a hexagonal pencil on an inclined plane. Am. J. Phys. 1 May 2009; 77 (5): 401-406. https://doi.org/10.1119/1.3098257

Eckert, Sidney & Ingalls, Phillip & West, J.. (2020). Rolling Polygons with Granular Material down an Incline. 10.48550/arXiv.2005.01545. https://www.researchgate.net/publication/341148751_Rolling_Polygons_with_Granular_Material_down_an_Incline

advanced

Beunder, E. M., and Rem, P. C. (March 27, 2003). "The Motion of a Rolling Polygon ." ASME. J. Appl. Mech. March 2003; 70(2): 275–280. https://doi.org/10.1115/1.1481893

Rosen, A. (March 12, 2000). "Modified Lagrange Method to Analyze Problems of Sliding and Rolling ." ASME. J. Appl. Mech. December 2000; 67(4): 697–704.  https://doi.org/10.1115/1.1328088

中正大學物理系 門福國 A “Flipo Flip” is a rigid body with a non circular convex edge and a deliberately placed center of mass. When you nudge it on a flat table it rocks and rolls along that edge, trading gravitational potential energy for rotational/translational kinetic energy. If the kinetic energy that survives friction and impacts exceeds the potential barrier between two neighboring “resting orientations,” it completes a flip and keeps going; if not, it stalls. ( ChatGPT

This Square Can Roll Like a Ball

YouTube, The Action Lab, 30.08.2020 https://youtu.be/eZM0WtB3UX8

A very good introduction on the mechanism of how a flipo flip works. The viewer will get a quick grasp on the physics involved in this problem.Before do anything, look up this YouTube film first.

Motion of a hexagonal pencil on an inclined plane

Amin Rezaeezadeh, Am . J. Phys. 77, 401 406 ( 2009)

Rolling Polygons with Granular Material down an Incline

Sidney Eckert, Phillip Ingalls, and J. West , arXiv:2005.01545