Motion control system

A mass damper system for use with a wheel of a vehicle, the mass damper system comprising:

• a damper fixed relative to an axis about which the wheel is configured to rotate;
• a spring fixed relative to the axis;
• and
• a damper mass coupled to the damper and the spring and configured to move relative to the axis to counteract vibrations produced by movement of the wheel, with the spring configured to bias the damper mass toward a neutral position and with the damper configured to dampen movement of the damper mass, the damper mass comprising:
• an internal surface configured to face away from the wheel, and
• an external surface spaced from the internal surface and configured to face toward the wheel,
• wherein the external surface extends between a first end and a second end, with the first end closer to the axis than the second end, and
• wherein at least a portion of the external surface tapers away from the axis and toward the internal surface further from the first end to direct debris away from the axis.

A mass damper system for use with a wheel of a vehicle, the mass damper system comprising:

• a damper fixed relative to an axis about which the wheel is configured to rotate;
• a spring fixed relative to the axis;
• and
• a damper mass coupled to the damper and the spring and configured to move relative to the axis to counteract vibrations produced by movement of the wheel, with the spring configured to bias the damper mass toward a neutral position and with the damper configured to dampen movement of the damper mass, the damper mass comprising:
• an external surface configured to face toward the wheel and extend between a first end and a second end, with the first end closer to the axis than the second end, and
• a ramp surface projecting outwardly from the external surface and extending between the first end and the second end, with the ramp surface configured to contact debris moving along the external surface and direct the debris off the external surface.