Constrain sketch to another sketch on a perpendicular plane

[wfp21]

I am unable to find a method to constrain two points on different sketches that are perpendicular to each other.

I want to force the centre of a rectangle (red circle) to lie on the tip of an eclipse (red dot) where each are on a different sketch and are perpendicular to each other:

Hope that makes sense. I have attached an ipt file in case.

Any suggestions appreciated.

Thanks, Will

[CGBenner]

@wfp21 

In Sketch1 place a work point at the top of the arc.  Save that sketch.  In Sketch3, project that point into the sketch, then use a Coincident constraint between the center of the rectangle and the projected point.  Voila.

[SBix26]

A slight correction: you need a sketch point at the top of the ellipse (though a work point could be used, too).  I see that you already have a sketch point constrained to the ellipse, but it's unconstrained otherwise.  Project the Y-axis to Sketch1, and the sketch point to that line as well:

Now that point is firmly located at the top of the ellipse, and you can project it into the other sketch and constrain to it.

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Sam B

Inventor Pro 2022.2.1 | Windows 10 Home 21H2

[CGBenner]

@SBix26 @wfp21 

You caught me.... I actually USED a sketch point, and just typed work point!  It's been a long week already.  Thank you for catching that!!

[wfp21]

Thanks for you very much for your quick replies but I am still rather confused!

How do I constrain my original sketch point in sketch 1? And then how do I project the Y-axis to Sketch1?

A screen-recording of how you solve it would be amazing.

Thanks again,

Will

[SBix26 · Accepted solution]

• Use the Project Geometry tool while in the sketch, then pick the Y-axis from the browser
• Best practice is to change the projected Y-axis to construction type so it's obviously not part of the ellipse profile
• Start the Coincident Constraint tool and pick the sketch point that is already constrained to the ellipse, then the projected Y-axis; the sketch point will change color to show that it is fully constrained.
• In Sketch3, use the same Project Geometry tool to project that fully constrained sketch point from Sketch1
• Use the Coincident Constraint tool to constrain the center of the rectangle to that projected point

This is all really basic stuff-- have you had any training??

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Sam B

Inventor Pro 2022.2.1 | Windows 10 Home 21H2

[wfp21]

I have had a little training but was unaware of the project geometry tool.

Projecting the point on sketch1 whilst in sketch3 made it visible for a coincident constraint.

Thanks for all your help

[SBix26]

It occurred to me later (middle of the night?) that there is no need for the sketch point or the Y-axis projection-- all that's needed is:

• In Sketch3, use Project Geometry to project the elliptical arc from Sketch1; it projects as a line, ending at the top of the curve
• Constrain the rectangle center to the endpoint of the projected line
• Finished

Sorry about all the extra work instructions the first time around.

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Sam B

Inventor Pro 2022.2.1 | Windows 10 Home 21H2