Help with Cams & Follower relations

[Anonymous]

I am teacher trying to show students how to devlop an egg shaped cam and flat follower relation.  I am having a hard time setting this up.  Any suggestions?

[mdavis22569]

Something like this?

https://www.youtube.com/watch?v=V1-1rCsfvcQ

[Curtis_Waguespack]

Hi jalsobrooks,

You can do this with a Transitional Constraint if you have the assembly set up correctly:

http://help.autodesk.com/view/INVNTOR/2015/ENU/?guid=GUID-EDE88086-58F3-4F62-A1CC-83CDB035BC27

What version of Inventor do you have? I might be able to attach some files that you can open.

In this image the yellow and orange faces are used as the constraint selections.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[Anonymous]

Inventor 2016

[Curtis_Waguespack]

Hi jalsobrooks,

These files are example from the Mastering Inventor 2015 book that you will be able open with Inventor 2016.

If those don't help, you might attach your files and someone will be able to provide some suggestions.

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[Curtis_Waguespack]

I also just saw this working example from JDMather too:

http://forums.autodesk.com/autodesk/attachments/autodesk/78/531138/1/Cam%20Shaft.zip

it's a better example of a flat follower (or flat ended in this case)

I hope this helps.
Best of luck to you in all of your Inventor pursuits,
Curtis
http://inventortrenches.blogspot.com

[JDMather]

Are you trying to use the Cam Generator Design Accelerator?

One common mistake is to use Tangent constraints (relations) between the Follower and the Cam.  Do not use Tangents - use Transistional as shown above.  The reason you can't use Tangent is because tangent is limited to two faces.  But in the image above the cam has several faces (one of them highlighted orange).  If the cam is generated from a continuous spline you might be able to use Tangent, but not if it has a seam.  In that case you might be able to replace with a seamless boundary patch.

What level are these students?  I have several advanced tutorials on cam motion using Dymamic Simulation.

If you have example files/reference that you are trying to reproduce - include that information.

[Anonymous]

Thanks.  This is exactly what I am trying to do.  The only issue I keep having is when I trying to put a transitional constaint on the cam it seperates the faces that I want the follwer to run on.  So it only allows me to run the constraints on part of the cam.  I developed the cam on my own.

[karthur1]

Its ok if it only shows the one face of the cam as the selection when you do the transitional constraint.  It will still select all the other faces.

What does it do when your drive (or just drag) the cam to make it rotate?  does the follower not stay on it?

Can you post your assembly and all the parts that go with it?  That will help if you can do that.

Kirk

[Anonymous]

I have attached the files I am using.  Platform Assembly is were I am trying to make the cam and follower connection.  I switched over from using PTC's Pro Engineer so I am not sure if I am doing this correctly.  

[karthur1]

I edited your Follower by adding a radius to the bottom of it.  Also edited the cam so the flat edges were tangent with the arcs at each end.  See attached video.

The translational constraint will work then.  I could not get it to work with the flat face on the follower.

http://screencast.com/t/Loe15fKdb

Kirk