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Mating belt to two shafts that can spin and move
miles_flusche536
Member Posts: 6 EDU
Hello, I have a plate with some bearings and retentioners with hex shafts through the middle. One of the shafts will be connected to another part that is fixed so that the plate will be able to rotate around the shaft. How do I mate the belt to the center of the hex shafts while the hex shafts can still spin and the plate can still rotate around the first hex shaft?
Thanks for all feedback in advance
0
Answers
that would be with a Revolute mate wouldn't it?
Yes, on the fixed point. The problem happens when I try to mate the belt to the second shaft. Because the whole arm can rotate around the first shaft, it also needs to be mated to the second shaft. No matter what mate I use for the second shaft, it always says that the mate isn't consistant. Is there a mate that just connects to the midpoint of the second shaft, not the shaft itself?
I should give you another picture to help explain.
The top plate that has the motors on it is the fixed plate. The hex shafts spin in the bearings, but the "Arm" also rotates. The Revolute Mate works for the first shaft connected to the top plate, but I can't find a way to mate the belt to the second shaft that can move with the plate when the plate rotates.
It is difficult to comprehend from text and picture alone. If you were to share your document by adding a link, others could look, make a copy and see what you have done and maybe suggest corrections by doing it in the copy and sharing it back to you?
This mechanism looks entirely possible BUT one wrong mate can give you grief and because so many things can move this is likely what happened.
Also if you mate one item in two different ways, and it conflicts in any kind of way, you will get some error and not always very clear as to what it was that caused it. Sometimes over-constraint, sometimes simply stops movement, sometimes even a positional error which goes back to one fixed mate that was rounded on 0.001 but the position of the next mate sits at 0.0011.
However in this picture I think most likely there is some wrong mate which looked to you to be on the correct part but which actually belonged to another part. To prevent this I now look specifically at which target marks get activated before I click on the suggested mate. If the other possible mates are not on the part you want to mate your movement to, keep moving the cursor until you find the part you want, then press hold shift and move to the mate you need, click and let go of shift. This way you can choose very carefully and accurately the mate you intended.
If this does not work for you please share the document so others can have a look as well.
Good luck!
from your description, is still think 2 revolute mates should work. but if the length of the belt is only a teeny tiny bit off from the pitch between the hex shafts, it won't work. Then maybe a pin-slot or tangent mate on the other side may be more robust.
Else I'm not understanding you well and like Kees said, a shared document may help us understand better.
Maybe you need a revolute on one end and a pin-slot at the other end to ensure no over-definition.
The belt itself can't "drive" anything (i.e. it's just for show), but you can use "gear relations" to tie in two rotations, if that's what you are asking…