The spinor linkage – a mechanical implementation of the plate trick

  title={The spinor linkage – a mechanical implementation of the plate trick},
  author={Alexander E. Holroyd},
  journal={Journal of Mathematics and the Arts},
  pages={133 - 161}
  • A. Holroyd
  • Published 4 July 2021
  • Engineering
  • Journal of Mathematics and the Arts
The plate trick or belt trick is a striking physical demonstration of properties of the double cover of the three-dimensional rotation group by the sphere of unit quaternions or spinors. The two ends of a flexible object are continuously rotated with respect to each other. Surprisingly, the object can be manipulated so as to avoid accumulating twists. We present a new mechanical linkage that implements this task. It consists of a sequence of rigid bodies connected by hinge joints, together with… 
The art of illustrating mathematics
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Apparatus for providing energy communicating between a moving and a stationary terminal. United States Patent US 3586413
  • 1971
Apparatus for providing energy communicating between a moving and a stationary terminal
  • United States Patent US 3586413
  • 1971
Belt trick
    Spinors and space-time: Volume 1
    • Two-spinor calculus and relativistic fields, volume 1. Cambridge University Press
    • 1984