Abstract: The current subject matter describes a device and system including one or more movable arms containing one or more magnets that are caused to move relative to a non-ferrous material by motion of the device to generate eddy currents that cause a braking of the device. Devices of this disclosure may include a wheel with arms having magnets and that move from centrifugal force caused by rotation of the arms within a wheel. The applied braking force is controlled due, in part, to the configuration of the non-ferrous material in which eddy currents are generated. Devices may additionally or alternately include arms with magnets that move relative to a non-ferrous rail when the device moves to generate eddy currents that cause additional braking of the device.