Problem with Mechanism Connection

[msöllner]

Hello,

please watch the video, I want that the upper parts stop when they have connection to the grey sheet-metal part.

I tried with cam follower connection, but without success.

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[lteckani]

Hi Maximillian,

After looking at your video, I understand that the upper parts don't have any connection to the grey sheet-metal part.

May I suggest a workaround where, there is a very thin, transparent 1mm wire touching the two surfaces so that you can model the animation to stop the upper part at the edge of the wire, touching the sheet metal surface? It's a bit of a dirty fix but might help if you are only interested in animating the assembly.

Regards,

Lucky

[ChrisKaswer]

You can use a cam-pair to get this situation (flat surface-to-flat surface) to behave properly - I have done it hundreds of times myself. The key is that one of the surfaces that makes contact needs to have a closed curve or surface as the cam geometry. Simply add the geometry to be coincident with the main portion of the part's contacting surface and make sure the closed geometry is a continuous and tangent between all segments. The second surface can be selected as a flat surface of the part that makes contact.

I hope this makes sense - good luck.

Chris

[msöllner]

Hello Chris,

what is a cam-pair? Can you give me an example in pictures or video how to use a cam-pair? That would be nice.

Thanks, Max

[ChrisKaswer]

It's just a cam follower. To Tim's point/question - is your goal to simulate the dynamics of your system, or simply create an animation of how it is supposed to operate? Your answer to this will have a significant influence on the approach you take to solve your problem. If it is a true dynamic simulation you wish to conduct, you will need to create a proper cam-pair to have it behave properly ...or you could also define a limit to the slider joint with a CoR to have it rebound as it would with real hardware.

[msöllner]

My goal is to simulate the dynamics. Please watch the Video A1.mp4, that is the mechanic I want to simulate. It only works in the video because the upper parts are depented on time. For example: ServoMotor1 from START till 2.45; ServoMotor2 from 7.55 till END.

When I define a limit to the slider and a ServoMotor from START till END, the simulate stops with message: assembly-anaysis failed.

I also tried to define a cam follower but I don`t have the knowledge to do this. I think a example could help me...

Video Link : 6737

[tmorishita]

Maximillian,

If you are only interested in stopping the upper parts for an animation, you can use the mate option in the snapshots dialog box, take a snapshot at that position, then use the snapshot as a key frame sequence. Otherwise, you may limit the amount of travel by editing the motion axis and setting a minimum and maximum amount of travel.