Most of the robots we feature only require a single Arduino board, because one Arduino can control several motors and monitor a bunch of sensors. But what if the robot is enormous and the motors are far apart? James Bruton found himself in that situation when he constructed this huge “tentacle” robot and his solution was to put an Arduino in each joint.

This is an oblique swivel joint robot arm, which means that each joint sits at an angle relative to the axes of the preceding and succeeding segments. This creates movement that is unlike any other kind of robot arm.

Bruton took this concept and scaled it up to ludicrous proportions. Each joint is a big ring made of plywood and 3D-printed parts, driven by a DC motor geared down 1600:1 and controlled through an ODrive module.

Because the robot is so large, it would have been difficult to run wires from a single Arduino to all of the motor drivers — especially because those have to go through slip rings to allow for continuous joint rotation. Instead, Bruton put an Arduino Mega 2560 board in each joint to control that joint’s motor driver. Those operate under the control of a primary Mega 2560 located in the base, with communication handled through a CAN bus system.

There is also another Mega 2560 in the remote control that Bruton built for the robot. That reads control input from switches and rotary encoders, then sends commands to the robot through a direct Wi-Fi connection (established via two ESP32 development boards). 

Bruton designed this robot to exhibit at EMF Camp in the UK, where it was a popular attraction.