Motion Link Not Able To Animate Properly

[Bruoyan16]

Here are images of the Huttlin Kugelmotor I tried to make. The curved pistons are supposed to swing back and forth as the four balls on them guide the rotation of the outer cylinder. Contact sets are too computationally intensive for this.  I limited the joints of the pistons to 0-35.8 degrees, but when I motion link the pistons with the cylinder, the cylinder joint is also limited because of the joint of the piston. How can I set up a motion link to make it so that the cylinder spins continuously while the pistons swing back and forth?

[jhackney1972]

You will probably need to upload your model in order for anyone to help you with your question.

[Bruoyan16]

Sorry, this is my first time, so can I get some instructions on how to upload my model?

[jhackney1972]

Sure, open your model and go to the File -> Export command.  You then choose a local folder of your choice then chose Export at the bottom of the dialog box.  Next go to forum and find the Attachment section, located below where you type your message.  Browser for the file your exported and open it.  This should attach the file.  Now an assembly, with linked components has to be sent differently.

[Bruoyan16]

Thanks, I uploaded it, though the file is a bit big, but when you get the file make sure you hide the engine case, the cover, and the stator to get a better view of the pistons.

[Bruoyan16]

Do you know anything about a motion link that can reciprocate one joint a certain number of degrees while the other joint is moving? Something like that is perfect for this problem.

[jhackney1972 · Accepted solution]

I do not know any way of using a motion link where one revolve rotates continuously and the other revolve osculates between o and a certain number of degrees.  I think you will have to switch to a Motion Study.  I do not like them because you cannot control the speed it executes.

[Bruoyan16]

Gotcha and thanks.

[Bruoyan16]

Now I have made use of the motion study and I have overcome this hurdle. The engine is animating the way I want it to because of your suggestion and I have accepted it as a solution, so thanks.

I do have a new question, when this motion study is established, is there a way to apply this new behavior to the joints such that when I drag on the components, they behave like shown in the animation of the motion study. Because when I click out of the motion study and I drag on the components, the behavior of the joints established by the motion link isn't there anymore.

[jhackney1972]

When I mentioned that Motion Links would probably not work earlier in your post, I said that because I "assumed" you wanted the rotational cam to rotate continuously as the piston rocked back and forth.  Motion links establish a relationship between the position / rotation of two joints so if you want rotational cam revolved more that the number of  degrees that activated the piston motions, it would fail.  I have not seen your final Motion Study but it does not link joints as a Motion Link does, it give you the ability to show Fusion a "relationship" between joints on a time scale.

I believe, since you know the exact angle(s) of the rotational cam and the angle of movement of the pistons which you placed in your Motion Study, you can translate these into a Motion Study.  The rotation cam will only rotate the number of degrees and the piston will rotate the number of degrees but that will be it.  Joints can be set to certain limits of motion in from the model browser.

Thank you for letting me know of your progress and the solution notation.