Line data: Spline starting shape

The spline starting shape data are required if the spline method is selected for step 1 statics.

Order

This controls the smoothness of the spline shape; generally, order 3 is reasonable. The higher the order, the smoother the resulting curve. The order cannot exceed the number of spline points.

Control points

The line shape is defined by a number of control points. The first and last control points are constrained to be at the line ends A and B respectively; OrcaFlex generates a smooth curve between the first and last control points and passing near to the intermediate control points. These intermediate points may be adjusted to 'pull' the curve into the desired shape, either by editing the X, Y and Z values on the line data form or by dragging the control points drawn on a wire frame 3D view.

The line is stretched to the specified as-laid tension and laid out along the spline curve, starting at end A and working towards end B.

For a line with a free end the line is laid out along the curve until end B is reached. If the length around the curve is not equal to the stretched line length then the end will either fall short of the end or lie beyond it (following the continuation of the curve in its 'final' direction).

For a line with an end connection which is fixed end, anchored, or made to some object, the curve is automatically expanded or contracted to allow the end to lie at the specified end position.

Drawing

The data which control the drawing, or not, of the spline and the pen used, are on the line drawing page.