Dynamic simulation of parallelogram mechanism

[Anonymous]

Hi everyone

I am new to the inventor simulation environment. I need your kind help to solve my problem. I have a double parallelogram mechanism intended to be used in pick and place mechanism. it is to be used to transport the end effector placed between and mounted to the two couplers of the parallelogram mechanism. I want check if the strength of the links is sufficient based on their sizes, and secondly I want estimate the torque required to run the mechanism. attached is the mechanism assembly

Thank you

[kelly.young]

Hello @Anonymous sounds like a difficult question. The file you attached is a .log, can you try again with Pack & Go as .zip for community members to inspect and comment on? 

Please select the Accept as Solution button if a post solves your issue or answers your question.

[Anonymous]

Hi Mr. Kelly

It seems to be difficult for learners like me. But professionals like you should find it easy I guess. I am sorry for attaching .log file. attached is the correct compressed folder. The zip is not in my 2016 version of the pack and go. Hope you can  help me out.

Thank you

Tukur

[TheCADWhisperer]

Any computer with Windows Operating System can Zip a folder.

Rar requires 3rd party software installation that I do not trust on my squeaky clean Inventor machine.

Can you use Windows OS to zip the folder instead of using *.rar?

MS Windows OS *.zip 

[Anonymous]

Thank you @TheCADWhisperer

Attached is the zip file

Thanks for your guidance

Tukur

[TheCADWhisperer]

Are you in a class learning how to do this?

The first thing I notice is that your part Sketch1  are not logically constrained relative to the Origin Center Point.

Have you installed all Service Packs for your version of Inventor?

[Anonymous]

@TheCADWhisperer I am not even learning it from a class, rather from the internet. I was asked to make use of it without any provision for training. Please bear with some anomaly you may see

Regards

[TheCADWhisperer]

There are several issues that would have to be overcome in solving this problem.

1. You are using 2016, which I do not have, so therefore I would have to create images/video for every step.

2. I would never allow a student into my Dynamic Simulation class if they had not first mastered basic sketching,

Dynamic Simulation (and Motion Loads Analysis) is an advanced topic.  There are some key foundational concepts that should be mastered to make it easier. One of these concepts (especially for your design so that you can avoid Over constrained Error) is modeling with symmetry about the origin.

If I examine Sketch1 of your Mechanism Platform - I see that the rectangle is floating in space.

It takes no more effort/time to create a centerpoint rectangle at the Origin than it does to create a floating 2-point rectangle.  (This is usually covered in the first 10 minutes of first Inventor class and should be automatic.)

And when it comes time to set up Dynamic Simulation the symmetry about the origin makes everything much easier.

Before I can go to Dynamic Simulation - we will have to fix each and every foundational issue.

While technically you might argue that these issues have nothing to do with Dynamic Simulation - it is the structured discipline in technique that I am emphasizing.  I have found that those who have mastered the foundation have far less trouble when the problems become complex to understand.

[Anonymous]

@TheCADWhisperer are you suggesting that I should make a new sketch at the origin?

[TheCADWhisperer]

Since you already have the rectangle - simply add a vertical and horizontal constraints to the midpoints.

Step 1

This is merely the first step of what will probably turn out to be a hundred or more edits.

[Anonymous]

@TheCADWhisperer I made the vertical and horizontal constraints and attached is what happened to the model

[TheCADWhisperer]

Do you know how to fix that?

[Anonymous]

To my understanding, I will delete the existing and constraint and constraint it again. If I am wrong please guide me right

[Anonymous]

I Just drag on it, and it get assembled back to normal

[TheCADWhisperer]

Next - all 4 of these mounting bosses are different geometry from each other.

We will have to fix this issue.

Why Different?

[Anonymous]

@TheCADWhisperer sorry for the late response, the last response I made it was already 2 am here, i was overpowered by sleep. I checked the bosses, the problem I observed was in the fillet, not the dimensions. The bosses are 30*30 mm each, the center slot of each boss is 10 mm in all the 4 bosses. Now I unify the fillet. Please confirm from the attached platform

Thank you

[TheCADWhisperer]

Symmetry is your friend when doing Dynamic Simulation.

Edit your Sketch1 and place the rectangle centered with symmetry about the Origin Center Point as shown below.

(Hey, wait a minute - that is the same thing that I wrote/demonstrated in Post #6, #8 and #10?)

Always use symmetry in design

[Anonymous]

@TheCADWhisperer I am sorry for that. I did it but forget to click ok. I have constraint it to the center point now as shown in the figure and as attachedconstraint to center point

[TheCADWhisperer]

You must have Attached the old file?

Still not correct?

You can see how at this rate it is going to take a while to get to the Dynamic Simulation solution....

[Anonymous]

@TheCADWhisperer I am sorry. please attached is the corrected one