Function sweep_solid_along 

pub fn sweep_solid_along(
    tool: &SolidTool,
    path: &FrameCurve,
) -> Result<BrepSolid, KernelRefusal>

The whole sweep of a solid of revolution carried by a frame along a curve. In the riding frame the velocity field is the speed along the tangent plus the turn about up, so the grazing loop moves on the tool with the curve’s curvature. It is split at sample times (its structure must not change), each piece sampled exactly, and the walls lofted through those samples (quintic both ways; the samples’ count doubles until the wall is within 1e-10 of the exact loop at the times between). Caps are the tool’s back at the start and front at the end.