N-DOF: The Modular Robotic Arm

thingiverse

# N-DOF: The Modular Robotic Arm Project This project utilizes connectors compatible with the Modular Mounting System (MMS) and GoPro to link motorized robotic modules together.  # Key Features: - **Modular**: Ideal for flexible use and re-use, try different arm designs without having to reprint parts. Easily disassemble and reassemble with ease. - **Limitless**: Print the same part multiple times and connect them together. N-DOF means "N Degrees Of Freedom". - **Extensible**: Use a motor or actuator in your robot? Design a joint with GoPro mounts separated by 30 mm, now it's N-DOF compatible! - **Compatible**: A huge number of mounts for various objects are already compatible with N-DOF. Search for "Modular Mounting System" or "GoPro".  # Included Modules: - The included modules use print-in-place joints to keep part count low, requiring supports when printing and a little force to move the first time. - Included modules use NEMA 17 stepping motors. - Only non-printed parts required are M3 bolts to mount the motors. If you're thinking of designing a module that's compatible with N-DOF, these features aren't a requirement. ### Base  - Gear ratio = 6:1 - Support blockers when slicing may help support removal. - For greater stability, print some MMS arms to spread the legs out further. - 2 x M3 bolts required to mount NEMA 17. - 6 x legs. - 1 x motor gear (with 12 teeth). ### Gear Joint  - Gear ratio = 4:1 - Support blockers when slicing may help support removal. - This joint has an asymmetric range of motion: -60 deg to 150 deg. - 3 x M3 bolts required to mount NEMA 17. - 1 x motor gear (with 12 teeth). ### Swivel Joint  - No gearing. - This could be improved using planetary gears. - 4 x M3 bolts required to mount NEMA 17. # Important Notes: - Regular PLA might not be strong enough for the M5 bolts. I used PolyMax PLA and had no issues. - If extending the arm to great lengths, make sure to attach the base to a desk with a clamp so it doesn't tip over. - OpenSCAD code can be found at https://github.com/keeeal/n-dof. # Useful Parts List: List coming soon.