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GyroMoment[bnum, vec, omega] returns a SysLoad data object that applies a moment to body bnum to simulate the gyroscopic effects of the axially symmetric body spinning with angular speed omega, about an axis originating from the centroid of the body, parallel to vec. The constant angular velocity omega is relative to the local reference frame of bnum.

• After creation, the SysLoad object is passed to SetLoads to alter the state of the current Mech model.
GyroMoment accepts the Inertia option to specify the inertia properties of the spinning body.
• If Inertia is unspecified, the inertia properties are taken from body bnum.
GyroMoment produces meaningful results only if the vector vec is parallel to a principal moment of inertia of the body, and if the other two principal moments are equal in magnitude. This implies that the body must be axially symmetric about the vector vec.
GyroMoment essentially models body bnum as if it were spinning at a constant velocity relative to its own local coordinates system.
• To model zero-torque motion, instead of constant velocity, use GyroFilter to remove the components of the inertia tensor that are aligned with vec from the body's inertia tensor.
• See also: Body, Load, Moment.

Further Examples

Load the Modeler3D package and define a simple model.

A load object is applied to the model that simulates the gyroscopic loads of a body spinning about the local X axis on the crank.

Solution->Kinematic is used here because the gyroscopic moments are a function of the angular velocity of the crank.

The reaction forces on the crank are orthogonal to both the spin of the gyro and the angular velocity of the crank.

See HelpModel3D.