High rate rotation sensing

An inertial measurement unit (IMU) for measuring an input rate of rotation about an input axis, the IMU comprising:

• a housing;
• a printed circuit board mounted in the housing;
• a first three dimensional gyroscope die mounted to the printed circuit board, the first gyroscope die configured to sense rotation about a first set of three mutually orthogonal axes, wherein the first gyroscope die is disposed such that a first axis of the first set of three axes is oriented at a skew angle in degrees away from a reference plane, the reference plan normal to the input axis;
• a second three dimensional gyroscope die mounted to the printed circuit board, the second gyroscope die configured to sense rotation about a second set of three mutually orthogonal axes;
• one or more processing devices mounted to the printed circuit board and coupled to the first gyroscope die and the second gyroscope die;
• and
• one or more data storage devices coupled to the one or more processing devices, the one or more data storage devices, including instructions which, when executed by the one or more processing devices, cause the one or more processing devices to:
• calculate a first rate of rotation by dividing a sensed rate of rotation about the first axis by the sine of the skew angle;
• and
• calculate the input rate of rotation based on the first rate of rotation and on a sensed rate of rotation by the second gyroscope about a second axis of the second set of three mutually orthogonal axes.