Revolute joint with torque input not moving (no error thrown)

Hello, I am building a simscape model of a 3DOF model, part of which I have pictured below. The mechanism giving me grief is rather simple, it is just a leadscrew mounted to a carriage. The revolute joint, "Revolute4" is giving me a lot of trouble and I believe it might (?) have something to do with my lead screw block, since this block in particular proved difficult to work with..

Essentially, when I move the carriage, via a prismatic articulation signal, the revolute4 joint will output a motion and position signal. However, when I try to drive this with torque input directly to the Revolute4 (and not the prismatic), there is no revolution of the joint. How do I resolve this? Simscape throws no errors and therefore I am more or less at a complete loss on how to troubleshoot this issue. I have attached the image of part of my project, unfortunately I will not be able to include the entire project but I believe this information is enough to begin with.

Thanks!

[Moritz Ischebeck]

It would be helpful to upload the project. Alternatively reproduce the error in a small simscape model.

Upload all the settings of Revolute4.

[Carson Lansdowne]

I'm reluctant to upload the project because it is company IP. Really, my question is why there is no error being thrown and how to deduce what is wrong with this joint. Like I said, when I force the translation, it is clear that it rotates but there is no torque output... When I input a torque, there is no rotation of the revolute joint.

Here are the settings for Revolute4

[Carson Lansdowne]

I'm reluctant to upload the project because it is company IP. Really, my question is why there is no error being thrown and how to deduce what is wrong with this joint. Like I said, when I force the translation, it is clear that it rotates but there is no torque output... When I input a torque, there is no rotation of the revolute joint.

Here are the settings for Revolute4. Aslo attached is the input signal for the joint and the torque output recorded..

[Carson Lansdowne]

I'm reluctant to upload the project because it is company IP. Really, my question is why there is no error being thrown and how to deduce what is wrong with this joint. Like I said, when I force the translation, it is clear that it rotates but there is no torque output... When I input a torque, there is no rotation of the revolute joint.

Here are the settings for Revolute4. Aslo attached is the input signal for the joint and the torque output recorded..

[Carson Lansdowne]

I'm reluctant to upload the project because it is company IP. Really, my question is why there is no error being thrown and how to deduce what is wrong with this joint. Like I said, when I force the translation, it is clear that it rotates but there is no torque output... When I input a torque, there is no rotation of the revolute joint.

Here are the settings for Revolute4. Aslo attached is the input signal for the joint and the torque output recorded..

[Carson Lansdowne]

[Carson Lansdowne]

[Yifeng Tang]

Is it possible to reproduce this problem without including your IP content, by removing details not related to the revolute joint movement? It's really difficult to figure out model problem from snapshots.

Answer 1

[Steve Miller]

I recommend you start from this example and work towards the system you have modeled above.

https://www.mathworks.com/help/physmod/sm/ug/lead-screw-with-friction.html

--Steve