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Why is this overdefined? Is there a better way?
faisal_quraishi
Member Posts: 4 ✭
I made this system and it works. But Onshape does not like it. What is wrong with it and is there a better way?
https://cad.onshape.com/documents/45312d75b65a08c854df6eef/w/481692290f5f2016f7caa290/e/803585c16bd45550e2056ec8
Best Answer
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jelte_steur814
Member Posts: 185 PRO
Slider1 creates a collinearity between these two blocks and so does the combination of the pin-slot and revolute. those two are conflicting.
Onshape creates some height differences between blocks. probably due to small errors accumulating.
another, perhaps cleaner way would be to change the Revolute into a Cylindrical…I solved it with a planar + parralel instead of the slider1 to allow this vertical difference to occur:
https://cad.onshape.com/documents/04be416927744252053fa09a/w/31ddb7780180b842a4be5668/e/6613da93d5592d6616fc12cb?renderMode=0&uiState=671f8bffdef678159c759b49
0
Answers
Slider1 creates a collinearity between these two blocks and so does the combination of the pin-slot and revolute. those two are conflicting.
Onshape creates some height differences between blocks. probably due to small errors accumulating.
another, perhaps cleaner way would be to change the Revolute into a Cylindrical…
I solved it with a planar + parralel instead of the slider1 to allow this vertical difference to occur:
https://cad.onshape.com/documents/04be416927744252053fa09a/w/31ddb7780180b842a4be5668/e/6613da93d5592d6616fc12cb?renderMode=0&uiState=671f8bffdef678159c759b49
Both the Pin slot mate and Slider 1 are constraining the x-axis translation degree of freedom of Part 1 <3>, thus overdefining the assembly. If you get rid of Slider 1 and the linear relationship, the assembly is not overdefined. Then, to get the proper motion of Part 1 <6>, you might be able to use a rack and pinion relation. Or model the actual mechanical relationships that should govern the motion of Part 1 <6>.
Thank you guys so much!