The base alone costs over $5,000 before adding an arm, computers and a paid motor license, so it suits labs rather than hobbyists.
TidyBot++ is an open mobile base for robot-learning research built from FRC robotics swerve modules, which act as powered casters so the base can move in any direction and rotate at the same time. Three reference frames carry arms of different sizes, such as a Kinova Gen3, a Franka or an ARX5, and the software includes phone-based teleoperation and diffusion-policy training. It came out of Stanford and Princeton and was presented at CoRL 2024.
At a glance
| Parts cost | $5,200–$6,300 (2024) parts list · Parts list totals for the mobile base, from $5,206 for the ARX5 size to $6,273 for the Franka size. They exclude the arm and computers and use academic pricing for the motors source ↗ |
|---|---|
| Difficulty | 4/5 Advanced · Mostly bolt-together vendor parts with a 10-hour assembly, but it needs a costly FRC drivetrain, a paid motor-controller license, CAN bus setup and an expensive research arm. |
| Build time | Around 10 hours of assembly over 1-2 days, plus about 3 days of 3D printing source ↗ |
| Tools needed | 3D printer (PLA; about 3 days of printing; Bambu Lab or Prusa recommended, Creality Ender not recommended), laser-cut acrylic plates (ordered from TAP Plastics), one custom machined shaft per caster (ordered from Xometry), imperial and metric hex T-handles, wire strippers, Loctite, Windows PC for Phoenix Tuner X |
| Motors | 4 SDS MK4 swerve modules with 8 Kraken X60 motors (steer and drive) and 4 CANcoder encoders |
| Controller | Mini PC with a CANivore USB-to-CAN adapter (Phoenix 6), plus a GPU laptop for policy inference |
| Sensors | Logitech C930e base and wrist cameras, caster encoders; arm is separate |
| Published | ✓ Parts list✓ CAD/STL✓ Assembly guide✓ Wiring✓ Software✓ Video MkDocs website (assembly and usage guide), Onshape and STEP CAD, GitHub code and resources repo |
| Activity | Last update 2025-12-18 · 618 GitHub stars · 72 GitHub forks, active issue tracker answered by the author |
| Kits | No complete kit; parts come from CTRE, WCP, SDS, AndyMark, Amazon, TAP Plastics and Xometry |
Licenses
No license is stated for the design files. They are published for building, but without a license the right to copy, modify or redistribute them is not granted.
| Design files | None found for the tidybot2-resources repo (STL, STEP, laser-cut and machining files); the docs site that publishes the parts list and CAD links is CC BY 4.0 source ↗ |
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| Code | MIT source ↗ |
| Documentation | CC BY 4.0 (assembly guide footer); the separate project homepage is CC BY-SA 4.0 source ↗ |
Builder notes
Practical points from the project's issue tracker, forum and docs, each linked to its source.
- The $199.99 Kraken X60 price in the parts list is FRC academic pricing. Non-academic builders are told to contact the vendor, so the real drivetrain cost may be higher. source ↗
- Field-oriented motor control requires a paid Phoenix Pro CANivore-bus license, which is activated through Phoenix Tuner X on a Windows computer. Builders who skip it see motors that blink but do not drive. source ↗
- The CANivore USB driver failed to install on a real-time kernel. One builder fixed it with a self-built RT kernel and the older CANivore 1.12 driver. source ↗
- The base ships with a 10 A drive current limit tuned for indoor thresholds and mats. A builder whose base stopped climbing small ramps fixed it by raising that limit. source ↗
- Phone teleoperation and policy learning are only released for the Kinova arm (plus teleop for ARX5, on a separate branch that was published only after a user asked). The other arms have mounting hardware only. source ↗
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