## General Mechanical

#### Revolut joint creation from 3D solid element???

• aoldac
Subscriber

Hello everybody,

I am trying to create revolut joint from 3D solid model. As it can be seen from the image I have rubber-metal vibration isolator. At the top and bottom of the isolator's metal parts there are cylindrical gaps where a frame go through. I tried to create contact surfaces between inner surface of isolator gap and the frame but when I run the simulation these isolator and frame behave as rigidly tied. Do you have any suggestion how to make frame rotate freely inside of isolator gaps? or if you can tell me where I am doing mistake?

Ahmet

• peteroznewman
Subscriber

Don't use Contact between a pin and hole, create a Revolute Joint to make a revolute joint.

If you have three solids, one for the top metal, one for the middle rubber and one for the bottom metal, then you can assign different materials to the three solids.

I can't help you with how to do that in APDL.  I work in the Workbench/Mechanical environment.

• aoldac
Subscriber

Hello Peter,

Thank you for advice, I am using GUI on APDL and I havent found built-in revolute joint command in it. I heard it can be done by using Multipoint constraints but havent figured it out yet how?

• peteroznewman
Subscriber

https://ansyshelp.ansys.com/account/secured?returnurl=/Views/Secured/corp/v195/ans_mul/Hlp_G_MULMODCOMPJT.html
Here are instructions on how to use the above URL.

## 2.3. Connecting Multibody Components with Joint Elements

The MPC184 family of elements serves to connect the flexible and/or rigid components to each other in a multibody mechanism.

An MPC184 joint element is defined by two nodes with six degrees of freedom at each node (for a total of 12 DOFs). The relative motion between the two nodes is characterized by six relative degrees of freedom. Depending on the application, you can configure different kinds of joint elements by imposing appropriate kinematic constraints on any or some of these six relative degrees of freedom. For example, to simulate a revolute joint, the three relative displacement degrees of freedom and two relative rotational degrees of freedom are constrained, leaving only one relative degree of freedom available (the rotation around the revolute axis).

• aoldac
Subscriber

Thanks a lot for helps. They were very helpful.