[iblis432]

to expand on Motorhead's explanation,
every control and indicator is actually a 'local variable'. In the functions pallete, go to Programming> structures and you will see the local and global variable 'vi' (though they are technically not VIs). You can right click these and change them between read and write.

For variables that go between VIs, you can create a global variable in your project. For the robot, I suggest passing data through the premade Global Robot Data file. To add data to this variable, just open it from the project explorer and add the controls that you want.