# The spinor linkage – a mechanical implementation of the plate trick

@article{Holroyd2022TheSL, title={The spinor linkage – a mechanical implementation of the plate trick}, author={Alexander E. Holroyd}, journal={Journal of Mathematics and the Arts}, year={2022}, volume={16}, pages={133 - 161} }

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…

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