How do I make a flexible tube? How would I make opposite and separate motions?

jacob_urbina232

So I was making a syringe hydraulic powered robotic arm and got all of the joints and main syringes set up, but how would I relate/mate the syringes moving the joints to other syringes which would simulate the controls by having one retract when the other extends? Also how do I make a part that is flexible in order to visually connect the controlling and reacting syringe?

MichaelPascoe

Hi @jacob_urbina232, please share a link to your model so we can help you better.

Retracting and extending can be done with mate relations. Specifically the Linear gear.
Flexible parts are not yet supported in Onshape.

Here are some workarounds that may help you with flexible parts:

Split part into multiple sections and place revolute mates and gear relations to simulate flex: 
https://forum.onshape.com/discussion/comment/80979#Comment_80979

Animate flex by swapping configurations per frame:
https://forum.onshape.com/discussion/comment/77717#1

jacob_urbina232

Oh and the model mates are a little messy but It is one of my first biggish assemblies

jacob_urbina232

Oh and the model mates are a little messy but It is one of my first biggish assemblies.

jacob_urbina232

Hi, thank you for your help. Below is the link to my model. I was able to mate the syringes to the joints, but I was wanting to somehow mate an external syringe to the syringe on the arm itself in order to simulate the way it works in real life. As the external syringe plunger is pushed inward, the plunger of the connected syringe should go out. This would be what I am trying to accomplish.
https://cad.onshape.com/documents/708218c3b3c2aacf5b56920f/w/effa5ee63d3c7c4beca6c4cf/e/8a94c227911dc3e8d837da1c?renderMode=0&uiState=63880cc3b7dceb4302b2ee97

MichaelPascoe

Any of the above methods should work, it will all depend on how much time you want to spend on it.

It is also possible to hide parts and still use them as guides keeping the "hoses" tight. The hoses could use a chain link approach with revolve mates.