Robot Visualization

A Python package for visualizing robots using URDF files and PyVista. This package provides an easy-to-use interface for rendering robots, updating joint configurations, and visualizing end-effector positions and trajectories.

Features

• Load and visualize robots from URDF files
• Update robot configurations in real-time
• Visualize end-effector positions and paths
• Coordinate axes and arrow visualization primitives
• Built on PyVista for interactive 3D rendering
• Includes urdfpy submodule for URDF parsing

Installation

Standard Installation

# Clone the repository with submodules
git clone --recursive https://github.com/MaximilianDio/robot_visualization.git
cd robot_visualization

# Install the package
pip install -e .

Development Installation

pip install -e ".[dev]"

Quick Start

Basic Robot Visualization

from robot_visualization import Robot
import pyvista as pv

# Create a plotter
plotter = pv.Plotter()

# Load a robot from URDF
robot = Robot("path/to/robot.urdf", plotter=plotter, color='lightgray', opacity=1.0)

# Set initial robot mesh
robot.set_robot_mesh()

# Show the visualization
plotter.show()

Update Robot Configuration

import numpy as np
from robot_visualization import Robot
import pyvista as pv

plotter = pv.Plotter()
robot = Robot("path/to/robot.urdf", plotter=plotter)

# Define joint configuration (adjust size based on your robot's DOF)
q = np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6])

# Update robot to new configuration
robot.update(q)

plotter.show()

Visualize End-Effector

import numpy as np
from robot_visualization import Robot
import pyvista as pv

plotter = pv.Plotter()
robot = Robot("path/to/robot.urdf", plotter=plotter)

q = np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6])
robot.update(q)

# Plot end-effector position
robot.plot_ee(q, ee_link_name="end_effector_link", color="red", size=0.02, type="sphere")

plotter.show()

Plot End-Effector Path

import numpy as np
from robot_visualization import Robot
import pyvista as pv

plotter = pv.Plotter()
robot = Robot("path/to/robot.urdf", plotter=plotter)

# Two different configurations
q1 = np.array([0.1, 0.2, 0.3, 0.4, 0.5, 0.6])
q2 = np.array([0.5, 0.4, 0.3, 0.2, 0.1, 0.0])

robot.update(q1)

# Plot path between two configurations
robot.plot_ee_path(q1, q2, ee_link_name="end_effector_link", color="blue", line_width=4)

plotter.show()

Using Visualization Primitives

from robot_visualization import AxesVisualizer, ArrowVisualizer
import pyvista as pv
import numpy as np

plotter = pv.Plotter()

# Create coordinate axes
axes = AxesVisualizer(plotter, origin=[0, 0, 0], scale=1.0)

# Update axes position and rotation
axes.update(position=[1, 1, 1], rotation=np.array([0.1, 0.2, 0.3]))

# Create an arrow
arrow = ArrowVisualizer(plotter, origin=[0, 0, 0], direction=[1, 0, 0], scale=0.5, color='red')

# Update arrow
arrow.update(origin=[0.5, 0.5, 0.5], direction=[0, 1, 0])

plotter.show()

API Reference

Robot Class

Main class for robot visualization.

Constructor:

Robot(urdf_file, plotter=None, **kwargs)

• urdf_file (str): Path to the URDF file
• plotter (pv.Plotter, optional): PyVista plotter instance
• color (str, optional): Robot mesh color (default: 'lightgray')
• opacity (float, optional): Robot mesh opacity (default: 1.0)

Methods:

• set_robot_mesh(): Initialize and render the robot mesh
• update(q): Update robot configuration with joint angles
• plot_ee(q, ee_link_name, color, **kwargs): Plot end-effector position
  • type: 'sphere', 'cube', or 'cross'
  • size: Size of the marker
• plot_ee_path(q1, q2, ee_link_name, color, opacity, line_width): Plot path between configurations

AxesVisualizer Class

Visualize 3D coordinate axes.

Constructor:

AxesVisualizer(plotter, origin=None, scale=1.0)

Methods:

• update(position, rotation): Update axes position and orientation
• plot_path(p1, p2, color, line_width): Plot a line between two points

ArrowVisualizer Class

Visualize 3D arrows.

Constructor:

ArrowVisualizer(plotter, origin=None, direction=None, scale=1.0, color='white')

Methods:

• update(origin, direction): Update arrow position and direction

Dependencies

This package requires:

• Python >= 3.7
• numpy
• pyvista
• scipy
• lxml
• networkx
• pillow
• pycollada
• pyrender
• trimesh
• six

All dependencies are automatically installed via pip.

URDF Submodule

This package includes the urdfpy library as a git submodule. When installing with pip, all urdfpy dependencies are automatically included.

License

[Add your license here]

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

Examples

See the examples directory for more usage examples (if available).

Troubleshooting

ImportError: No module named 'urdfpy'

Make sure you cloned the repository with submodules:

git submodule update --init --recursive

Visualization window not showing

Make sure you call plotter.show() at the end of your script.

Robot not updating

Make sure to call robot.update(q) after changing joint configurations.