srdf

The SRDF skill provides MoveIt2 semantic robot description generation, validation, and planning-semantics workflow management. It addresses the critical challenge of defining correct planning semantics on top of existing URDF robot models. While URDF defines physical robot structure (links, joints, geometry), SRDF defines how MoveIt should plan motions by specifying planning groups, end effectors, collision behaviors, and default poses. The skill enforces a rigorous workflow to prevent common failures where plausible but incorrect SRDF files give MoveIt wrong planning groups, tool links, or unsafe collision matrices.

The skill's main capabilities include creating and editing SRDF files with proper validation against source URDFs, defining virtual and passive joints, establishing planning groups from URDF topology using chain-based definitions for serial manipulators, configuring end effectors with correct target links, defining group states in URDF-native units (radians for revolute joints, meters for prismatic), and generating disabled collision matrices from evidence rather than inference. It maintains a planning ledger at `references/planning-ledger.md` to track planning requirements before generating XML, and integrates with the CAD Viewer skill for live review and optional MoveIt2 interactive controls.

This skill targets robotics engineers and developers working with MoveIt2 motion planning who need to create or modify semantic robot descriptions. Primary use cases include setting up arm inverse kinematics, configuring gripper controls, defining mobile base planning semantics, establishing dual-arm planning configurations, and validating planning semantics before deployment. The skill explicitly separates concerns: use the URDF skill for robot structure, the SDF skill for simulator descriptions, and the CAD Viewer skill for rendering and live review with MoveIt2 controls.