fedoo.constraint.DistributedForce.set_element_local_frame

DistributedForce.set_element_local_frame(frames=None, location='Element', *, guide=None, guide_direction=None)

Define the initial local frame of beam or shell elements.

The element geometry fixes one axis of the frame. For a beam, the local x axis is aligned with the element tangent. For a shell, the local z axis is aligned with the surface normal. Consequently, a supplied frame does not override these geometrical directions; it determines the rotation of the remaining two axes around them.

guide provides a simpler way to define this remaining orientation. For beams it approximates the local y axis by default, or the local z axis with guide_direction="z". For shells it approximates the local x axis. The guide is projected onto the plane perpendicular to the geometrically fixed axis, and the last axis is then completed to form an orthonormal, right-handed frame.

frames and guide may be uniform, elemental, or nodal. Nodal values are interpolated to the element centres before the geometrical projection is applied.

This method must be called before problem initialization. A Gauss-point field is intentionally not accepted because an element rigid frame is independent of the integration rule.