Power management for an interface device that is manipulated by a user and
in communication with a host computer and provides forces to the user. The device
includes a sensor and an actuator. One embodiment provides first power from the
host computer over a serial interface and second power from a power adapter. Another
embodiment provides first power from the host computer and second power from a
power storage device on the interface device that supplies power to the actuator.
Another embodiment provides a power adapter supplying a portion of the first power
to the sensor and a portion to the actuator, and a power storage device on the
interface device provides second power to the actuator.