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BUY A 40,000-DOLLAR INDUSTRIAL ROBOT FOR 200 AND BUILD ITS BRAIN

A six-axis factory robot that sold new for tens of thousands turns up on eBay for a few hundred dollars because the controller cabinet is locked and proprietary, and this project builds the missing brain.

by Excessive Overkill

FULL CAD BOM FIRMWARE DOCS

RoboticsOpen-hardware

difficulty
●●●●●
time
a serious project
license
CERN-OHL-W-2.0 / GPL-3.0
repo
repo ACTIVE0 stars

WHAT YOU’LL NEED

Videos
1
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COMPAREE VERDICT

ExcessiveMotion is an open-source universal machine controller built to bring scrapped industrial robots back to life without their proprietary cabinet. It runs on a MYiR Zynq-7000 module: Linux on the ARM cores for high-level control and FPGA logic for the real-time parts. Instead of reusing the robot's original electronics, the project publishes its own high-voltage servo drive, an encoder card and a Fanuc RJ3iB encoder breakout, plus a pendant, brake module and GUI. In the video, a robot listed as a 40,000-dollar machine was bought for 200 dollars and brought back to life, then shown at Open Sauce. All hardware (CERN-OHL-W-2.0) and software (GPL-3.0) are published, but the creator says it is not yet plug-and-play. You will be decoding your robot's encoders, building and tuning high-voltage drives and doing your own integration. This is for people comfortable with FPGAs, real-time systems, high-voltage power electronics and the safety discipline industrial machinery demands.

GOOD TO KNOW

  • —Hardware schematics, PCB layouts, and Gerbers are published in the ExcessiveMotion GitHub organization.
  • —FPGA HDL for the real-time servo loops and ARM Linux userspace code are both in the repositories.
  • —Bills of materials are published for the MYiR Zynq interface board and the DB25 encoder card (controller-hardware) and for the HV servo drive revisions (drive-hardware).
  • —There is no assembly manual, step-by-step commissioning guide, or structured documentation on reverse engineering a specific robot model.
  • —The project is under active development; expect to read code and schematics directly.
  • —Licence is CERN-OHL-W-2.0 (weakly reciprocal) for hardware and GPLv3 for software; both permit commercial use, with changes to the licensed design shared back.

Parts to buy

5 items

From our check of the build. Exact quantities and part numbers are in the creator’s BOM.

  • MYiR Zynq-7020 SoMFind
  • Controller interface PCB and encoder cardsfrom the repo files
  • Project's own open HV servo drives or compatible drivesFind
  • Power suppliesFind
  • Scrapped industrial robot armFind

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Can I build this?

Printnothing required
BuyMYiR Zynq-7020 SoM, the controller interface PCB and encoder cards (fabricate from the published files), the project's own open HV servo drives (one per axis) or compatible drives, power supplies, and a scrapped industrial robot arm
ToolsPCB assembly station or assembly service, FPGA toolchain (Vivado), oscilloscope for signal tracing, fenced or guarded work area for a multi-ton arm, high-voltage safety equipment
SkillsFPGA development, real-time embedded Linux, servo drive tuning, reverse engineering serial protocols, and industrial safety discipline; this is a 5/5 difficulty project
Timea serious project — weeks to months depending on your robot model and how much reverse engineering is required
Cost$$$, dominated by the Zynq SoM, PCB fabrication and assembly, and the robot arm itself (a few hundred dollars used, but transport and rigging add cost quickly)
SafetyIndustrial arms move with lethal force and require a fenced or interlocked work area. Servo drives carry high-voltage DC bus capacitors that remain charged after power-off. This is not a desktop project.

Build at your own risk. Projects involve tools, electronics and sometimes mains voltage — follow the creator’s safety notes.

Videos

Primary project video from the creator's Excessive Overkill channel; details of the protocol reverse engineering and the Open Sauce 2025 demo.

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Gallery

Start here

Navigation into the creator’s own docs — we don’t rewrite the guide, we route you to the source.

  1. 1.Browse the ExcessiveMotion GitHub organization repositories (Hardware schematics, HDL and software are split across nine repos; start with controller-hardware (MYiR interface board, encoder card, Fanuc breakout) and controller-software.)
  2. 2.Watch the Excessive Overkill channel project video (Shows the reverse engineering process and the arm running; this is the best overview of what the project actually involves.)
  3. 3.Identify a candidate robot arm(The published encoder breakout is for Fanuc RJ3iB arms. Know what motors and encoders your target robot uses before you buy it.)
  4. 4.Set up the FPGA toolchain(The FPGA project needs Vivado 2023.1, Python 3.12 and VS Code; the Linux image is built with PetaLinux.)

Resources

Documentation, files and community threads for this build — we link straight to the original sources and never rehost the creator’s files.

KNOWN ISSUES

  • Every robot family uses different motors and encoders. The published interface covers Fanuc RJ3iB encoders; anything else means decoding its encoders and adapting the hardware yourself.
  • Budget for more than the robot: the Zynq module, the controller and encoder boards, one high-voltage drive per axis, power supplies, cables, rigging and transport. Price it from the BOMs before you start.
  • There is no assembly manual or structured commissioning checklist; expect to read schematics and code to understand how the pieces connect.
  • High-voltage servo drive capacitors stay charged after the main power is off; you must discharge them safely before touching anything.
  • A multi-ton robot arm requires a fenced or interlocked work area, not a garage bench; if you do not have that space or cannot build it, the project stops there.
  • Active development means the repositories may change structure or pinout; clone and version-lock before you order PCBs.

Can I use this controller with any industrial robot?

Not out of the box. The project replaces the robot's drives with its own high-voltage servo drives and reads the robot's encoders; the published encoder breakout is for Fanuc RJ3iB arms. Another robot means working out its motors and encoders and building your own interface.

Do I need to design my own PCB?

No. The KiCad files, BOMs and Gerbers for the MYiR interface board, the DB25 encoder card and the Fanuc RJ3iB encoder breakout are published in controller-hardware, and the HV servo drive is in drive-hardware. You fabricate and assemble them, or send the files to a PCB assembly service.

What is the Zynq doing that a normal microcontroller cannot?

The FPGA fabric handles the time-critical work in hardware, while the ARM cores run Linux with the controller software for motion planning and the user interface.

How much does a scrapped industrial robot actually cost?

In the video the creator bought one for 200 dollars. Prices vary widely, and transport, rigging and the drives and electronics you need to build add to that.

Is this safe to run in a home workshop?

Only if you build a proper safety fence or interlock system. Industrial robots move with enough force to kill, and there are no built-in collision limits unless you program them. This is not a collaborative robot.

Community builds

No community builds yet — be the first, we feature the best ones.

Discussion1

FROM THE COMPAREE TEAM

The project ships its own servo drive and a Fanuc encoder breakout, with the stated goal of being a universal machine controller. If you have a scrapped industrial arm sitting around, which brand or model would you try to bring back first?

CompareeTEAM1mo agoedited

Practical notes from our verification: the GitHub organization has nine separate repositories (controller, drive, pendant, brake module and GUI, each split into hardware and software) and no single README that ties them together, so expect to explore them one by one. The main controller-software repo describes itself as an open-source universal machine controller and links a software setup document; the hardware repos are KiCad designs under CERN-OHL-W-2.0, the software under GPL-3.0. Notably, the project includes its own high-voltage servo drive and an encoder breakout for Fanuc arms. The YouTube video is the best entry point for understanding what the project actually does. This is a real open-source motion controller, but it is not plug-and-play; adapting it to a new machine means doing real integration work yourself. Correction (4 October 2026): we re-checked this page line by line against the project's own repository, documentation and videos, and fixed errors in earlier versions.

Excessive Overkill

The creator runs the Excessive Overkill YouTube channel. He bought a scrapped industrial robot cheaply, built a new open-source controller and drives for it, decoded its encoders and showed it running at Open Sauce.

GitHub

Star the project on GitHub

DISCLAIMER

  • Comparee is not the author of the projects featured here. All rights to each project belong to its creator — every page links to the original source, and we never host creators’ files.
  • Information is provided without warranty and may become outdated as projects evolve. Prices are indicative bands only — always check the creator’s parts list for current costs.
  • Building and operating any project is at your own responsibility. Protective equipment, safe workshop practice and compliance with local regulations are the builder’s responsibility.
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