Cannot apply tangent constraint between curve and circle on 2D sketch

[xandmore3]

Hello everyone! Could you help me with that please: for some reason I cannot apply tangent constraint between circle and spline curve. Curve is never being highlighted when I hover it 🤷
What could it be?

I tried to draw a new curve and go through the same steps and it worked - it allowed me to apply a tangent constraint. So that might be that the problem is somehow related to the previous curve.

I'm attaching a part file, so as a recording, showing the problem.

Thank you! 🙇

[JDMather]

If that were my design - I would sketch with the Origin as a datum at a logical location.

I would sketch the rectangle, circles and slot relative to the Origin datum.

For the spline I would sketch only one curve and use Shell to get the Offset.

My sketch would be fully defined.

[WHolzwarth]

I didn't look at fully constraining the sketch, but I've added an offset spline for the center of the circle.

[xandmore3]

@WHolzwarth @JDMather 
Thank you, gentleman! The solution suggested by @WHolzwarth works perfectly fine 👍

Anyways, I'd love to know the reason of that inability to apply tangent constraint to the circle and the spline.

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I didn't look at fully constraining the sketch

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After I removed all the other constraints on the sketch I still couldn't apply it 🤔

Is there any limitations of applying tangent constraints towards splines? Where could I find more information about it?

For the spline I would sketch only one curve and use Shell to get the Offset.

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 Is it crucial to have a single curve to be able to apply tangent constraints? 

[SBix26]

I experienced something like this recently, too.  I could not get a line to constrain tangent to a spline curve in a 2D sketch.  Either one of them would highlight as the first pick, but for the second pick, nothing was available to select.  This was in Inventor 2022.3.1.

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Sam B

Inventor Pro 2023.1 | Windows 10 Home 21H2

[johnsonshiue · Accepted solution]

Hi! I think this is a limitation in Tangent constraint. It seems that a tangent constraint cannot be established between a circle and a fit-point spline except the handle at a fit point.

The second image shows the tangent constraint between a control-vertex spline and a circle. It is indeed supported. To enable the tangent constraint in this case, right-click on the fit-point spline -> Convert to CV Spline.

Many thanks!