As I rotate the arm, the gears are rotating on its own and the jaw is moving. I need to constrain this gear rotation while the arm moves. I also want the rack-pinion gear mechanism to work independently to arm movement. How can I achieve this?
I don't have a complete answer for you but something you might try. Does it make sense to have your gears and jaw in a sub-assembly?
I don't know if you have your gears mated using the "gear mate" and if that is making this better or worse.
You could also add a mate that gives the gear an orientation parallel to your main block. Move the arm, then suppress the mate to move the gears.
If you can, upload your files for a proper looking.
How can I attach a file to a forum post?
The 11th Weekly Power-User Challenge (October 20th, 2017): Flipping Mates - Robot Case Study and go to the 99th reply and take a look at that video and setup.
This is can be done using a few sketches and spline lines/spline circles and sketch points mated coincident to those splines. It'll possibly take a bit of trial and error till you get the correct combination..
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