DexRobot URDF Models
This repository contains URDF models for a dexterous robotic hand system, including both left and right hand configurations. The models are compatible with standard URDF toolchains and have been tested with MuJoCo.
Quickstart
The URDF models can be visualized using MuJoCo’s simulate
tool:
# For left hand
simulate urdf/dexhand021_left.urdf
# For right hand
simulate urdf/dexhand021_right.urdf
Note: After launching the simulator, hit the ‘Pause’ button first, then ‘Reset’ to properly visualize the model in its initial configuration.
Models
Full Model
The full model provides high-fidelity mesh files suitable for rendering and visualization. It includes detailed geometry for all components of the hand.
Simplified Model
A simplified version optimized for simulation is also provided. This model reduces geometric complexity while maintaining kinematic accuracy, making it more efficient for physics simulations. Solidworks project files for these simplified models are included in the repository.
Model Conventions
Naming Convention
The model follows a systematic naming convention for links and joints:
Base Format:
[lr]_[type]_[component]
[lr]
: ‘l’ for left hand, ‘r’ for right hand[type]
: ‘p’ for palm components, ‘f’ for finger components[component]
: specific component identifier
Component Numbering
Thumb Rotation:
*_1_1
Finger Spread:
[2345]_1
(for index, middle, ring, and pinky fingers)Metacarpophalangeal (MCP) Joints:
[12345]_2
Proximal & Distal Joints:
[12345]_[34]
(for all fingers)Note: While proximal and distal joints are mechanically coupled in the physical system, this coupling is not reflected in the URDF model
Frame Convention
The model primarily follows the Denavit-Hartenberg (DH) convention for frame assignments:
Base Frame
Origin: Located at the wrist
Z-axis: Points toward fingertips
Thumb Orientation: Inclines toward negative X-axis for both hands
Additional Resources
The repository includes utility scripts in the utils/ directory for URDF file processing and analysis. These tools can help with tasks such as updating mesh paths and analyzing model properties.
Notes for Users
Mesh files are referenced relative to the URDF location using
../meshes/
The models are compatible with major robotics simulation environments that support URDF
While the URDF models don’t enforce joint coupling, users can implement this in their control software
The utility scripts can be modified as needed to accommodate specific requirements