variable sweep da spline

[vale31]

Maybe it's a trivial question, but he's giving me some scratch.

I need to create a variable section sweep with origin on a passing 3d spline for only 2 points created in 3d.

the problem is that if I create 2 random points in 3d and I make the spline (which obviously will be straight) after clicking the vss does not enter me into sketch... (It is not even possible to select the sketch icon)

there are so many ways to solve the problem, for example by creating a passing plan for the 2 created points and on this floor create a sketch on which to draw a segment or a spline 2d

the fact is that the extreme points of the spline coincide with the center of the reference system and the center of a secondary reference system created on Cartesian coordinates, and must in the future be modified both as x y z coordinates and on the 3 corners, so it can not be a 2d spline.
Moreover the spline is tangent to 2 axes of the 2 Cartesian systems, for example the 2 x axes, so that when I move the reference systems the spline is no longer a segment but a curve. (I need flexibility in asm)

I make an example, if I create a second reference system with the 3 equal angles and coordinates x = 100, y = 100, z = 0 the spline is a curve, not a segment, being tangent to the passing axes by x, in this case I can create the vss (the file is set in this way)

at the moment when zero y (then I get x = 100, y = 0, z = 0) the spline becomes a segment and it is no longer possible to build us over the vss.

Why?

in addition to the solution I would also like to understand how mathematically he thinks. .. seen that I still have other ways to solve the problem, but I would like to understand this

proe wf 5.0

 

[cletus]

good morning, try setting the top floor as a reference for controlling the x direction of the section at the beginning of the trajectory, do not leave it by default.
I checked the help and here is suggested this:

horizontal/vertical control (horizontal/vertical control) - determines rotation control modes around the normal sketch plan along the variable section sweep.
○ Automatic (automatic) - the section plane is automatically oriented in the xy pro/engineer direction calculates the direction of the x vector so that the sweep geometry is twisted as little as possible. this is the default setting for a trajectory origin without reference surfaces. the direction reference collector allows you to define the initial section or orientation of the x axis of the pane at the beginning of the sweep. Sometimes it may be necessary to specify the direction of the x axis, for example in the case of straight line trajectories or trajectories starting with a right segment.

I can't explain why of all this.
Hi.

 

[vale31]

actually so it works... I had tried to change the section plane control but not the x direction.. .

Thank you!