Consistent Model Descriptions for the Visualization and Simulation of a Reconfigurable Parallel Kinematic Structure in ROS2

This contribution addresses the integration challenges of the PARAGRIP robot, a reconfigurable parallel kinematic manipulator, into ROS2. Despite its exceptional capabilities in Multidirectional Additive Manufacturing with pure object manipulation, its closed kinematic loops impede direct ROS2 integration. Available solutions use a conversion of incomplete URDF models to SDF. However, this approach lacks a clear ‘Single Source of Truth’ for the robot model. Furthermore, a solution for the parametrization of non-treelike closed-loop topologies is missing. Therefore we propose a novel concept for the simulation and visualization of robots with closed kinematic loops in ROS2. Introducing Embedded Ruby in SDF files greatly enhances parametrization capabilities. By extending the functionality of the pysdf conversion tool with an optional cut parameter, we enable the automated conversion of closed-loop kinematic SDF models into treelike URDF files. Additionally, a joint state conversion methodology is presented to seamlessly integrate the PARAGRIP robot into the ROS2 simulation and visualization pipeline.