The Dynabee is a gyroscopic device that is marketed as a wrist exerciser. In this paper, a model for the dynamics of this device is presented. With some additional work, we find that the dynamics are governed by a single ordinary differential equation. The solution of this equation also provides the moment required to operate the device. Specifically, we find that this moment is proportional to the square of the rotor’s spin rate. We also show why it is necessary to give the device a large initial spin rate for its successful operation. [S0021-8936(00)02602-7]

Issue Section:
Technical Papers
Keywords:
gyroscopes, dynamics, differential equations, kinematics
Topics:
Differential equations, Dynamics (Mechanics), Kinematics, Rotation, Rotors, Equilibrium (Physics)
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 by ASME
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