dreamscale-i2rt

Dreamscale Labs' maintained build of the I2RT Python API, published to PyPI so the YAM driver installs like any other package:

pip install dreamscale-i2rt

It installs the same i2rt import package, so it replaces an upstream i2rt install in the same environment rather than sitting beside it. The core install is what YAM arm control needs; the Flow Base, gamepad, visualisation, GPIO and script dependencies are extras (flow-base, gamepad, viz, gpio, scripts, or all).

This is a fork. I2RT Robotics wrote the original code under the MIT licence; see LICENSE. Releases are tagged v<version> and published from publish.yml.

I2RT Python API

A Python client library for interacting with I2RT products — designed for learning-based robotics, teleoperation, and real-world deployment.

📚 Full documentation: doc.i2rt.com

Features

• Plug-and-play Python interface for YAM arms and Flow Base
• Real-time robot control via CAN bus (DM series motors)
• MuJoCo gravity compensation, simulation, and URDF/MJCF models
• Gripper force control and auto-calibration
• Bimanual teleoperation and trajectory record & replay
• Policy-deployment ready — works with standard robot learning pipelines

Installation

git clone https://github.com/i2rt-robotics/i2rt.git && cd i2rt
curl -LsSf https://astral.sh/uv/install.sh | sh
source $HOME/.local/bin/env
uv venv --python 3.11
source .venv/bin/activate

sudo apt update
sudo apt install build-essential python3-dev linux-headers-$(uname -r)
uv pip install -e .

CAN Bus Setup

# Check detected CAN devices
ls -l /sys/class/net/can*

# Bring up interface at 1 Mbit/s
sudo ip link set can0 up type can bitrate 1000000

# Auto-enable on boot
sudo sh devices/install_devices.sh

# Reset unresponsive adapter
sh scripts/reset_all_can.sh

YAM Arm

Arm variants

Every arm is six-DOF. Pick one with --arm on any CLI, or arm_type= in Python. A hardware revision is its own variant — yam_ultra_2 is revision 2 of the YAM Ultra.

"Arm mass" excludes the gripper and tips. "Chain length" is the sum of the parent-to-child joint-origin translation norms — a measure of the kinematic chain, not of reach. Each arm's model README tabulates full masses, COMs, inertias, joint frames, DH parameters, and screw axes.

Zero-gravity mode

python i2rt/robots/motor_chain_robot.py --channel can0 --arm yam --gripper linear_4310

Python API

from i2rt.robots.get_robot import get_yam_robot
from i2rt.robots.utils import ArmType, GripperType
import numpy as np

robot = get_yam_robot(
    channel="can0",
    arm_type=ArmType.YAM,
    gripper_type=GripperType.LINEAR_4310,
)

# Read joint positions (radians)
q = robot.get_joint_pos()   # shape: (6,)

# Command a target configuration
robot.command_joint_pos(np.zeros(6))

Leader-follower teleoperation

# Follower arm
python examples/minimum_gello/minimum_gello.py --gripper linear_4310 --mode follower --can-channel can0 --bilateral-kp 0.2

# Leader arm (teaching handle)
python examples/minimum_gello/minimum_gello.py --gripper yam_teaching_handle --mode leader --can-channel can1 --bilateral-kp 0.2

• Top button (press once): enable synchronisation — follower tracks leader
• Top button (press again): disable synchronisation
• --bilateral-kp controls resistance felt on the leader (0.1–0.2 recommended)

To inspect leader arm output:

python scripts/run_yam_leader.py --channel $CAN_CHANNEL

MuJoCo visualiser

python examples/minimum_gello/minimum_gello.py --mode visualizer_local

Gripper Types

The linear grippers require calibration because their motor travels more than 2π radians over the full stroke — either start with the gripper fully closed, or run the calibration routine.

Flow Base

# Joystick demo
python i2rt/flow_base/flow_base_controller.py

from i2rt.flow_base.flow_base_client import FlowBaseClient

client = FlowBaseClient(host="172.6.2.20")
client.set_target_velocity([0.1, 0.0, 0.0], frame="local")

Examples

Advanced: Motor Configuration

Safety timeout

The factory default is a 400 ms timeout — motors enter damping mode if no command is received within 400 ms.

# Disable timeout (advanced users only — run twice)
python i2rt/motor_config_tool/set_timeout.py --channel can0
python i2rt/motor_config_tool/set_timeout.py --channel can0

# Re-enable timeout
python i2rt/motor_config_tool/set_timeout.py --channel can0 --timeout

⚠️ Without the timeout, a failed gravity-compensation loop can produce uncontrolled torque. If you disable it, always initialise with a PD target:

robot = get_yam_robot(channel="can0", zero_gravity_mode=False)

Zero motor offsets

python i2rt/motor_config_tool/set_zero.py --channel can0 --motor_id 1

Run for each motor ID (1–6 for a standard YAM).

Motor registers

Read and write a motor's configuration registers (IDs, control mode, protection thresholds, MIT scaling, loop gains) over CAN. Full register table and safety notes: dm_motor_registers.md.

# List every register the tool knows about (no CAN bus needed)
python i2rt/motor_config_tool/dm_motor_registers.py list-registers

# Read one register, or dump them all
python i2rt/motor_config_tool/dm_motor_registers.py read sw_ver --motor-id 1 --channel can0
python i2rt/motor_config_tool/dm_motor_registers.py read-all --motor-id 1 --channel can0

# Change a value: write puts it in RAM, save commits it to Flash
python i2rt/motor_config_tool/dm_motor_registers.py write MAX_SPD --value 30.0 --motor-id 1
python i2rt/motor_config_tool/dm_motor_registers.py save MAX_SPD --motor-id 1

⚠️ Stop any program using the bus first, and only ever save a register you have just successfully written — saving an unwritten register has been observed to revert other unsaved registers to their stored values. Changing ESC_ID, MST_ID, CTRL_MODE, can_br, TIMEOUT, PMAX, VMAX or TMAX asks for confirmation on the console first.

Contributing

Pull requests welcome. Open an issue to request examples or report bugs.

License

MIT License — see LICENSE.

Support

• Email: support@i2rt.com
• Sales: sales@i2rt.com

Acknowledgments

• TidyBot++ — Flow Base hardware and control inspired by TidyBot++
• GELLO — Teleoperation design inspired by GELLO