Designing a winglet for an airplane wing, using loft and guide curves

Chris_Schellhase

Hey guys, i've searched for hours, but couldn't solve my problem. I want to loft the main wing into a winglet using three airfoils. the airfoils are imported as dxf and positioned free handed in seperate sketches. every airfoil consists of around 260 points/lines.

I created two guide curves, one at the leading edge and one at the trailing edge. I want the ledaing and the trailing edge to be tangential to the ones of the main wing, and I drew the guide curves with respect to that.

When I try to use the leading edge guide curve, it would create a self-intersecting body, because guide curves only act on their particular vertices.

Maybe one of you pros has an idea how to solve this issue, I would be very thankful!

Here's the link to the public document:
https://cad.onshape.com/documents/9d56a12139bd678c5e989a18/w/01d36219154277ea3c774133/e/06687ed64e9e28192f6c3cbd?renderMode=0&uiState=657230012b9121779d1133b8

Cheers
Chris

MichaelPascoe

Hi @Chris_Schellhase,

The first thing you need to do is simplify your profiles so that there are as few of spline points as possible; I would say no more than ~10 per profile. This will make for a smoother spline in turn helping your loft and other features. The more points, the more "bumpy" your spline will be. You can still achieve the same wing profile, but your points will be in optimized locations to create a very smooth shape.

The reason your loft is self intersecting, is most likely because some of your many points are getting crossed across the guide curves. Reducing your spline points down to 10 or so per profile, should fix this issue as well.

Tip: You don't have to delete your spline sketches, you can use them as a reference for a new sketch containing your smooth spline profile.

MichaelPascoe

Hi @Chris_Schellhase,

The first thing you need to do is simplify your profiles so that there are as few of spline points as possible; I would say no more than ~10 per profile. This will make for a smoother spline in turn helping your loft and other features. The more points, the more "bumpy" your spline will be. You can still achieve the same wing profile, but your points will be in optimized locations to create a very smooth shape.

The reason your loft is self intersecting, is most likely because some of your many points are getting crossed across the guide curves. Reducing your spline points down to 10 or so per profile, should fix this issue as well.

Tip: You don't have to delete your spline sketches, you can use them as a reference for a new sketch containing your smooth spline profile.