Arctos Robot Arm
Ultimate Goal
Learn robotics hands-on while experiencing the challenges of participating in an open-source hardware project.
Skills Acquired
Technical Skills
- • Fundamentals of motion control and motor-driven design
- • CAD troubleshooting and part modification for fit and tolerance
Project Skills
- • Respect for the complexity of open-source hardware maintenance
- • Documentation design and assembly manual creation
Project Overview
I was drawn to the Arctos robotic arm for two reasons: aesthetics and affordability. The Bill of Materials came in under $400, and the arm simply looked cool. But beyond that, I saw it as a chance to dive intomotion control, motor-driven assemblies, and robotics programming.
This project was about learning in multiple dimensions. By assembling the arm, I got to see firsthand the design decisions that go into motion transmission. I wanted to explore how to program robotic arms — eventually tackling concepts likeinverse kinematics — and, most importantly, I wanted to experience the realities of contributing to someone else's open-source hardware ecosystem.
Key Challenges
Entering with zero prior robotics experience
Errors and inconsistencies in the assembly manual
Fragmentation across project versions, making it hard to follow along
Wiring and electronics hookup being more difficult than anticipated
Enormous BOM: 50+ 3D-printed parts, hundreds of fasteners and hardware
Solutions & Innovations
Initially planned to build the open-loop version, but pivoted to closed-loop control after realizing the design didn't allow enough clearance for open-loop wiring. The closed-loop version also promised higher accuracy.
Followed the original design closely, but contributed back small CAD fixes (like resizing mismatched holes in the Y-core gear).
Learned from Arctos's own Cadasio assembly manual, which directly influenced me to create an assembly manual for the Portable Data Node.
Outcome & Results
The arm is currently in teardown for a full conversion to closed-loop electronics. My plan is to use it as a demonstration piece and potentially as a prop at Neotropolis 2026.
Beyond the hardware itself, the project taught me patience: understanding that frustration is inevitable when tackling something this complex, and the value of taking breaks before diving back in.