ENGINEERING.com MeArm Pi Delivers a Robotic Arm Powered by Raspberry Pi ENGINEERING.com Servos are pre-calibrated for users to assemble and immediately start using the system. The HAT itself is designed for B+ form factor Raspberry Pi models, based off of the 40 pin GPIO header.

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MeArm Pi Delivers a Robotic Arm Powered by Raspberry Pi – ENGINEERING.com