A motion link's ratio is read in b's units per a's (mm per degree, degrees per mm) when an angle and a distance are linked; stored values stay per radian, so saved designs are unchanged. Follow-up to #1415.
Co-authored-by: SychPL <[email protected]>
joint.motion_link offset is read in the linked value's units (degrees or mm, or an expression); links are still stored in radians, so saved designs open unchanged. A new joint whose values fall outside its limits starts at the nearer limit, stores it, and says so in warnings. Loop dof also counts at a nearby pose, so a part at a dead point of its loop keeps its mobility. The mechanisms skill is updated to match.
The Joint and As-built Joint dialogs explain why picks make no joint and offer Create Components from Bodies when every pick is on one component; joint.create and joint.as_built suggest component.from_bodies. Labels in all catalogs. Fixes#1239.
A solidcraft-mechanisms agent skill with a worked example that a test replays through the MCP server (the actuator follows the hinge with the stated stroke and the drive stops at the rod's limit); the skills index and docs/mcp.md list it.
A design with components and joints exports as a URDF robot description (file.export to .urdf, the MCP export tool, solidcraft-cli run --out, File > Export URDF...). It writes one binary STL per component in metres, links with mass, centre of mass and inertia from material density, and maps rigid, revolute, slider, cylindrical, pin-slot, planar and ball joints to URDF joints or short chains. Loops, broken joints and loose parts are reported as warnings. Options: mesh_prefix, effort, velocity. Docs in docs/urdf.md.
Corrects the modeling skill: an edge of the face a shell removes is rounded after the shell, a slot along Y is dimensioned horizontally, long shallow arcs measure to about 0.1%, and a boolean retry warning can hide wrong geometry when the volume does not match.
