literobo 0.1.0

Lightweight URDF kinematics (forward kinematics + Jacobian) with Rust speed and Python bindings.

literobo

Lightweight kinematics utilities for URDF robots, implemented in Rust with Python bindings.

Features

• Parse URDF files and build a kinematic chain between any two links.
• Forward kinematics that returns a homogeneous transform.
• Geometric Jacobian for revolute and prismatic joints.
• Python bindings powered by PyO3 and packaged with maturin.

Rust usage

use literobo::KinematicChain;

let chain = KinematicChain::from_urdf_file("robot.urdf", "base_link", "tool_link")?;
let pose = chain.forward_kinematics(&[0.0, 0.5, -1.0])?;
let jacobian = chain.jacobian(&[0.0, 0.5, -1.0])?;
println!("Pose:\n{}", pose.to_homogeneous());
println!("Jacobian:\n{}", jacobian);

Python usage

The project is configured for uv so you can manage dependencies and builds without a virtualenv toolchain mismatch.

# Create an isolated environment
uv venv
source .venv/bin/activate

# Install build dependency and compile the wheel
uv pip install maturin
uv pip install .

import numpy as np
import literobo

robot = literobo.from_urdf_file("robot.urdf", "base_link", "tool_link")
q = np.array([0.0, 0.5, -1.0])
pose = robot.forward_kinematics(q)
jacobian = robot.jacobian(q)

print("Pose:\n", pose)
print("Jacobian:\n", jacobian)

To publish, run uv build (which delegates to maturin under the hood) and upload the wheel to PyPI with uv publish.

Quick sample run (Python)

Below is a minimal end-to-end example you can run locally:

# 1. Prepare environment (inside repo root)
uv venv
source .venv/bin/activate
uv pip install maturin  # build backend

# 2. Build & install the wheel from the checked-out source
uv pip install .

# 3. Create a tiny planar robot URDF
cat > planar.urdf <<'URDF'
<robot name="planar">
  <link name="base"/>
  <link name="link1"/>
  <link name="link2"/>
  <link name="tool"/>
  <joint name="joint1" type="revolute">
    <parent link="base"/>
    <child link="link1"/>
    <origin xyz="0 0 0" rpy="0 0 0"/>
    <axis xyz="0 0 1"/>
  </joint>
  <joint name="joint2" type="revolute">
    <parent link="link1"/>
    <child link="link2"/>
    <origin xyz="1 0 0" rpy="0 0 0"/>
    <axis xyz="0 0 1"/>
  </joint>
  <joint name="tip" type="fixed">
    <parent link="link2"/>
    <child link="tool"/>
    <origin xyz="1 0 0" rpy="0 0 0"/>
  </joint>
</robot>
URDF

# 4. Run a short script
python - <<'PY'
import numpy as np
import literobo

robot = literobo.from_urdf_file("planar.urdf", "base", "tool")
q = np.array([0.0, 0.5])

pose = robot.forward_kinematics(q)
jac = robot.jacobian(q)

print("Pose:\n", pose)
print("Jacobian:\n", jac)
PY