The motion of a Slinky walking down a set of stairs is modeled by a simple dynamical system with two degrees of freedom undergoing inelastic collisions. Numerical integration of the model’s equations of motion shows that the model’s behavior is similar to observations of the motion of an actual Slinky. In particular, it is found that the model’s motion exhibits a periodic gait, although subject to more restrictive launch conditions than an actual Slinky.

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