The maker identified wire routing and managing the robot’s weight as the most complex aspects of this design. The resulting articulated arm, inspired by the Boston Dynamics Spot Arm, is built from PETG and is intended for mounting on the back of a SpotMicro robot dog. It incorporates MG996R servos, utilizing a PCA9685 servo driver, and is controlled by a Raspberry Pi 3B+.
Standout features include the end effector, which has an illuminated blue LED module, and the control box, which contains a red toggle switch and an internal light shifting through blue, green, and red. The wrist joint allows for both pitch and yaw movement, achieving 180 degree rotation, limited by the hobby servo capabilities. Exposed wiring harnesses link the internal motors throughout each joint.
While the arm performs a programmed sequence including rotation, dipping, and tilting, the maker is still working on reducing its wobble. This issue is somewhat alleviated by using the controller to slow the arm’s motions. The overall assembly weighs roughly 1.7 lbs, but the payload capacity has not been tested yet. The maker is still developing the project's GitHub repository, and adding inverse kinematics formulas remains a task ahead!