I'm not sure if this idea has been discussed yet in the 500+ pages of this thread, but would it be at all possible to control the rotation/movement of parts based on a user-defined equation? I am currently working on mechs that utilize mechanisms, such as the Chebyshev linkage, to control the movement of its legs. It would be significantly easier to control the rotation of a single rotatron with an equation than it is to create and adjust a multi-rotatron/docking washer and -pivotron system. Also, do any free-moving gantry rail edits exist? I have had a need for free moving, linear servos, but couldn't find a good way to do it with unpowered rotatrons, although two, oppositely-rotating powered rotatrons with an unpowered rotatron have worked the best. Any suggestions for this?