Bimo Robotics Kit – Open-Source Bipedal Robotics Platform

Bimo is an open-source bipedal robot created to make bipedal robotics research more accessible in a compact platform. Get started with pre-built kits or customize the design. Includes complete CAD files (coming soon), RP2040 firmware, Isaac Lab training environment, and a Python API for real-time control and model deployment.

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Key Highlights

• Fully Open Source: CAD files (coming soon), firmware, simulation and deployment code.
• Sim-to-Real Ready: train policies in Isaac Lab, deploy directly on hardware.
• Baseline Walking Model: deployed directly from simulation, without adaptation.
• Two Configurations: available as a fully assembled SLS kit or a DIY 3D-printable edition.
• Fast Training: vectorized Isaac Lab environment to train policies in ~5 minutes (depends on hardware).

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Main Features & Specifications

Feature	Specification
Height	45 cm
Weight	~1.6 kg
Actuators	8 servo motors (STS-3215)
Sensors	BNO08x 9-DOF IMU, 4× TOF distance sensors, 2x 180ºFOV Cameras
Controller	Custom RP2040-based board compatible with SBCs through data and power connectors
Communication	USB 2.0 (PC or SBC)
Power	9V-13V. Includes adapters to Banana Plugs and Power Jack. Sold without battery: battery-compatible
Compute	Offboard on PC, or onboard using an SBC mounted inside the head
Design	Hip-head biped. Empty head cavity with 4 x M3 mounting points, designed to house an SBC or custom hardware
Control Loop	20 Hz

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Quick Start Guide

Prerequisites: This guide assumes you have an SLS kit (ships fully assembled, firmware pre-loaded and pre-calibrated) or a completed DIY build with firmware already flashed. If not, see the MCU Instructions for flashing instructions.

Step 1: Install the Python API

cd BimoAPI/
pip install -e .

See BimoAPI for full API documentation.

Step 2: Connect Data & Power Cables

Unscrew the 7 screws on the bottom plate to open the head.

Data cable: Connect the 3m USB data cable to the DATA port on the PCB. See the MCU documentation for port location. Route the cable through any of the hatches for easier use.

Power cable: Connect the power adapter cable (included) into the XT-30 port. This allows plugging in an external power supply via standard banana plug cables (not included).

Step 3: Stand Up & Verify

Write a minimal Python script to test basic functionality:

from bimo import Bimo

bimo = Bimo()
bimo.initialize()  # Connects MCU + cameras, moves to sit, calibrates IMU
bimo.perform("stand")

Ensure the cables connected between Bimo and the host PC are not pulling down on it, as this can interfere with the stand-up routine.

Powering Up: After connecting the USB Data cable to the host PC, allow ~5s for the MCU to boot and switch-on the servo power rail before running any API scripts.

DIY Kit Only: Run bimo.initialize(calibrate=True) on first use to calibrate servos. See the DIY Manual (coming soon) for full assembly and calibration instructions.

Step 4: Train & Test Walking Model

Follow the IsaacLab Instructions, then train the walking model:

cd IsaacLab/
./isaaclab.sh -p scripts/reinforcement_learning/rsl_rl/train.py --task Bimo --num_envs 2048 --headless

Export the trained policy as ONNX, then deploy using the api_example.py script:

import onnxruntime as ort
from bimo import Bimo

bimo = Bimo()
bimo.initialize()
bimo.perform("stand")
bimo.lock_heading()  # Required for walking model

session = ort.InferenceSession("policy.onnx",
    providers=["CUDAExecutionProvider", "CPUExecutionProvider"])

# See BimoAPI/examples/api_example.py for the full inference loop

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Repository Structure

the-bimo-project/
├── README.md                # Main project README
├── CHANGELOG.md             # Main project CHANGELOG
├── LICENSE                  # Apache 2.0
├── .gitignore
│
├── BimoAPI/                 # Python control library
│   ├── setup.py             # Package setup (mekion-bimo)
│   ├── README.md            # BimoAPI documentation
│   ├── CHANGELOG.md         # BimoAPI version history
│   ├── bimo/
│   │   ├── __init__.py
│   │   ├── bimo.py          # Core Bimo control class
│   │   └── routines.py      # Pre-programmed behaviors
│   └── examples/
│       └── api_example.py   # Complete inference example
│
├── IsaacLab/                # RL training environment
│   ├── README.md            # Training guide
│   └── bimo/
│       ├── __init__.py
│       ├── bimo_config.py   # Robot & actuator configuration
│       ├── bimo_task_env.py # Full Isaac Lab task environment
│       ├── agents/
│       │   ├── __init__.py
│       │   └── rsl_rl.py    # RSL-RL PPO hyperparameters
│       └── assets/
│           └── Bimo.usd     # USD robot model
│
└── MCU/                     # Microcontroller firmware
    ├── README.md            # MCU protocol & setup
    ├── CHANGELOG.md         # MCU version history
    └── micro_bimo.ino       # RP2040 firmware (Arduino IDE)

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Roadmap

Q1-Q2 2026:

• Community development
• Progressive Bimo updates
• CE/FCC Certification

Q3 2026:

• First kits ship: SLS, DIY options available
• Manuals, DIY assembly tutorials, CAD models

Q4 2026:

• R&D Team Constitution
• Project Maintenance & Development
• Contribution setup

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Partners & Supporters

Organization	Details
	EOI: Escuela de Organización Industrial
	JLCCNC: High quality CNC machining services

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License

All code and CAD designs are, and will, be released under the Apache 2.0 License. See LICENSE for details.

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Links

• Website: mekion.com
• Discord: Mekion | The Bimo Project
• X(Twitter): @mekionlabs
• YouTube: @mekionlabs

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Contact

For questions, partnerships, or press inquiries:

• Email: info@mekion.com

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Built with ❤️ by Mykhaylo Ilyin. Making bipedal robots accessible.

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