AnsweredAssumed Answered

Newbie needs Motion Study help - Redundant Mates and wrong torque

Question asked by Douglas Kimber on Feb 26, 2014
Latest reply on Apr 4, 2019 by Inho Sung

As the title says, I'm a newbie to SW Motion (and SW as well, really). I want to do some pretty detailed motion studies, so I decided to try some tutorials first to get a better understanding of how Motion works. I did the 4 link tutorial on page 13 of "Introduction to Solid Modeling Using SolidWorks 2011" :

 

https://d2t1xqejof9utc.cloudfront.net/files/14496/SolidWorks_Motion_Tutorial_2011.pdf?1348074885

 

Everything went as expected until I  increased the motor speed from 60 RPM to 600. Motion worked, but the resultant forces were identical between both cases, with a peak torque of about 52. The tutorial shows the max torque as 180 at 600 RPM.

 

The motion analysis says I have 3 mate redundancies. I modeled each of the 4 joints as hinge mates. (I tried previously with concentric/coincident mates at each of the 4 joints. In that case I had 8 mate redundancies, but the results were identical).

 

So, my questions are:

 

1) What am I doing wrong in the tutorial that prevents the motor torque from increasing?

 

2) Is there a clear description of what the mate redundancies really are? I tried deleting some mates, but when I ran Motion some of the parts flew off the screen!

 

3) What is the real difference between a "Hinge" mate and the pairing of "Coincident/Concentric" mates?

 

4) Is there a 3D equivalent of a "Hinge" mate that I should use when my assembly uses ball joints or spherical joints such as heims?

 

5) Is there a good/simple way to confirm motion analysis results? If I had only run the 600 RPM example above and believed the output I might have selected a motor that was too small.

 

Thanks in advance!

 

Doug

Outcomes