Rigging an Extendable Robot Arm?

Hey all,


I'm quite stuck thinking of how I would rig a bendy, extendable robot arm.

Here is a figure below of the desired effect. Does anyone have any ideas how this could be accomplished? Hide extra pieces of the arm mesh inside the body? Any help is appreciated!



P.S. I plan to model the arms as simple cylinders, with smaller rings of black joint materials separating each segment. So the rig does not have to worry about any "arm texture," only preserving the shape of the underlying model, which should be able to extend at least 3x the base length. Stretching the arms will not do, as it does not seem robotic - which is why I'm a bit stuck.

  • Martin Říha(hadiczech) replied

    I am not sure, if this is the right way, but i would try to create the arm as a curve, and those parts could be via array and curve modifier put on that curve with "fit length" option. It is just firs idea, so it could be wrong...

    i created this example (it was quick, so nothing fancy): https://drive.google.com/open?id=1oXl5DAuS4it7nhs0SocdfDbKdnFd0Ww6

    just select the bezier curve and try to move it

  • polygondust replied

    hadiczech Wow, thank you, that works great! Thanks for taking the time to make that.

    How did you get it to spawn more sections as you pull it out? Is in not modeled at all, but instead generated by the bezier?

    This model is planned for animation, so the only issue is how as you pull, each new section rigidly springs into place, causing the hand to clip back and forth noticeably, so the animation would not be smooth. I'll look into maybe tweaking this solution to fix that issue. Thanks again for the help!