Robowflex Visualization

Visualize motion plans and robots in tandem with robowflex_library in Blender.

Requirements

1. Blender must be installed with COLLADA loading support (*.dae).
2. python3-yaml for loading YAML files.
3. The ROS package collada_urdf for translating URDFs into COLLADA files.

package:// URIs are supported by calling the rospack command-line tool. Blender should be run in an environment with your ROS workspace sourced.

Design

This package provides the robowflex_visualization Python library intended for use within Blender. All code for this library is within the robowflex_visualization folder.

Usage

1. Dump a trajectory to a YAML file via the robowflex::Trajectory::toYAMLFile() function. An example of this can be found in robowflex_library/scripts/fetch_test.cpp:

   ...
   // Generate a plan
   planning_interface::MotionPlanResponse res = planner->plan(scene, request.getRequest());
    
   // Output path to a file for visualization.
   robowflex::Trajectory trajectory(res.trajectory_);
   trajectory.toYAMLFile("fetch_path.yml");
   ...

Planning scenes can be edited manually by writing the YAML file (an example is in robowflex_library/yaml/test.yml), or by calling robowflex::Scene::toYAMLFile() on a loaded planning scene.

1. Edit the provided file, scripts/robowflex.py to use your desired files. Note the loaded files for the trajectory and scene in the following script:

   import robowflex_visualization as rv
    
   # Load a robot under the name `Fetch`
   fetch = rv.robot.Robot("Fetch", "package://fetch_description/robots/fetch.urdf")
    
   # Animate a trajectory
   fetch.animate_path("package://robowflex_visualization/yaml/fetch_path.yml")
    
   # Add a planning scene.
   scene = rv.scene.Scene("Scene", "package://robowflex_library/yaml/test_fetch.yml")

2. Open blender from the current terminal and open the provided robowflex.blend Blender scene. To the left should be a baked in Python script (if there is no script, it is also available at scripts/blender.py). This script sets up the system path for the built-in Blender Python to look at your Python3 system path as well as load the robowflex_visualization Python module. Run this script to execute whatever code you have in scripts/robowflex.py. You can change what script is called.
3. Lather, rinse, repeat! You can edit code outside the Blender editor, everything should be reload appropriately.

Examples

robowflex_library/scripts/fetch_test.cpp

You can render still images of robots.

robowflex_library/scripts/ur5_test.cpp

As well as full animations of motion plans.