Joints: cam and follower coupling (joint.cam) (#1734)

Thanks @SychPL.

ROADMAP.md

@@ -54,7 +54,7 @@ PCB / Package, Render, Animation, Simulation, Manufacture/CAM, Drawings.
 | M6 | UI depth: selection feedback and origin (done), timeline editing (done: hover and selection highlight modifier faces, including fillets and chamfers; edit feature, history marker drag, dependency-checked single and multi-item reorder, suppress, rename, delete with dependents, re-resolved references; redefining selections refreshes persistent edge/face references while retaining feature identity and dimension names; optional compact named left feature history with rollback bar, multi-selection and persistent folders above the parts browser), right-docked dialogs (done), live previews for every feature dialog (done), keyboard-first commands with on-canvas value boxes and sketch inline dimensions (done), drag manipulators with automatic join/cut (done: extrude incl. two sides, fillet, shell, hole depth, move, pattern spacing, revolve rotator; taper handle open), dark theme (done), right-click menu with Repeat (done), measure tool (done), section analysis (done), selection filter (done), drag-solve of sketch points (done); appearance controls now preserve body/face/component targeting, named transparent looks, reuse/search and override removal; preferences | in progress | 6 |
 | M7 | Thin extrude (walls along open or closed curves: centre, inside, outside or two sides; mitred corners, crossing walls joined; #721), sweep, loft (incl. to a point), rib and web (to next / depth), emboss (planar faces and exact radial emboss/deboss of bounded orthogonal profiles on complete exterior cylinders/sleeves), thread (cosmetic, and modelled M3–M20 outside and inside: the ISO profile screwed in as a faceted cut), coil (smooth B-spline helical walls), pipe, pattern on path, patterns of bodies and components, replace face (parallel), align, remove, feature copy/paste: done. Unique eligible cylindrical targets are inferred for new Emboss features. Left: general curved-face emboss and exact (unfaceted) modelled threads | in progress | 12 |
 | M8 | Surface workspace (#772). Done: Patch (sketch regions; edge loops filled G0, plus `crown`), Stitch, Thicken (planes and cylinders), Extend (straight edges of planar surfaces), Trim (by a plane or a face), Delete Face (healing), Boundary Fill, zebra/draft/curvature-map analysis, Surface Extrude/Revolve/Sweep/Loft from open and closed curves, Offset, Unstitch and Reverse Normal; the continuity-driven core (`kernel/src/bridge.rs`, G0–G3 Hermite rows) with **Blend** (`surface.blend`, #764), **Match** (`surface.match`), **Boundary** (`surface.boundary`, #763 — two boundaries exact, three/four refused pending a Gregory-type corner), **Fair** (`surface.fair`, CV fairing), **continuity analysis** (`inspect.continuity`, #770) and a multi-section **loft** with per-end continuity and crown. Also in the Class-A pass: G1…G4 blend curves in the sketch, chord and variable-radius fillets on curved edges (with honest refusals where the fit cannot hold), and a G2 corner patch where filleted edges meet (kernel; the command refuses until the patch's sections can be sewn to the blends' contacts). Left: bias/form-factor fillet sections (design recorded), a Gregory-type corner, surface Fillet between separate surface bodies (#769), Ruled (#762), Untrim (#761), curved-face Extend (#760), sweep guide rails and two-rail sweeps (#771; orientation, twist and end scale done; loft rails #201), and every remaining #757–#772 item | deferred | — |
-| M9 | Components and assemblies: New Component / Create Components from Bodies, active component, per-component origin/bodies/sketches/timeline entries, occurrences with transforms, Copy/Paste vs Paste New, nested Browser tree with visibility and isolate; Ground, Move/Copy of occurrences, joints (rigid, revolute, slider, cylindrical, pin-slot, planar, ball) by joint origins with limits and Drive Joints, closed kinematic loops (four-bar, slider-crank: the loop's other joints follow the driven one on its branch, and driving stops where a loop can no longer close), As-built Joint, Rigid Group, Contact Sets (driving and motion studies stop where bodies in a set would pass through each other), Motion Study (joint values keyed along a timeline, playback, export of occurrence positions as JSON/CSV), Exploded views (automatic or by hand, shown without changing placements); interference, per-component physical properties; STEP with assembly structure; URDF export for robot simulators (links with meshes, mass and inertia; joint chains whose values match Drive Joints; docs/urdf.md). Physical properties now measure material-aware component/occurrence placements, descendants and repeated instances, including pending moves and body reassignment offsets; contact geometry and automatic exploded centres respect those offsets. Groundwork done: component tree, occurrences with transforms (instances, Paste New), world placement, active component as authoring frame, ground, Capture/Revert Position, moving bodies and sketches. UI: ASSEMBLE panel dialogs for New Component, Joint (snaps on faces, edges, circles and vertices; animated motion preview; offsets, flip, limits), As-built Joint, Joint Origin, Rigid Group, Drive Joints (live slider), Motion Link and Interference (overlaps shown red); joints in the timeline and the Browser | in progress | 32 |
+| M9 | Components and assemblies: New Component / Create Components from Bodies, active component, per-component origin/bodies/sketches/timeline entries, occurrences with transforms, Copy/Paste vs Paste New, nested Browser tree with visibility and isolate; Ground, Move/Copy of occurrences, joints (rigid, revolute, slider, cylindrical, pin-slot, planar, ball) by joint origins with limits and Drive Joints, closed kinematic loops (four-bar, slider-crank: the loop's other joints follow the driven one on its branch, and driving stops where a loop can no longer close), cams (`joint.cam`: a revolute cam drives a slider or revolute follower along a closed sketch profile or the cam's edges, knife, roller or flat followers, worked out again when the profile changes; drives, studies, closed loops, contact sets), As-built Joint, Rigid Group, Contact Sets (driving and motion studies stop where bodies in a set would pass through each other), Motion Study (joint values keyed along a timeline, playback, export of occurrence positions as JSON/CSV), Exploded views (automatic or by hand, shown without changing placements); interference, per-component physical properties; STEP with assembly structure; URDF export for robot simulators (links with meshes, mass and inertia; joint chains whose values match Drive Joints; docs/urdf.md). Physical properties now measure material-aware component/occurrence placements, descendants and repeated instances, including pending moves and body reassignment offsets; contact geometry and automatic exploded centres respect those offsets. Groundwork done: component tree, occurrences with transforms (instances, Paste New), world placement, active component as authoring frame, ground, Capture/Revert Position, moving bodies and sketches. UI: ASSEMBLE panel dialogs for New Component, Joint (snaps on faces, edges, circles and vertices; animated motion preview; offsets, flip, limits), As-built Joint, Joint Origin, Rigid Group, Drive Joints (live slider), Motion Link, Cam and Interference (overlaps shown red); joints in the timeline and the Browser | in progress | 32 |
 | M10 | Sheet metal: flange (base, edge, contour), hem, unfold/refold, convert, flat pattern + DXF, rules: done. PLASTIC enclosure subset: Boss, Rib, Web, Lip/Groove, Snap Fit, Rest, Plastic Rules (library, edit, assign; rule draft and clearance as feature defaults): done, tested against hand-computed geometry. UI: SHEET METAL and PLASTIC tabs in Fusion's layout with dialogs (live preview, Edit Feature, pre-selection) for Flange, Hem, Unfold/Refold, Convert, Sheet Metal Rules, Create Flat Pattern (flat view with bend lines, bend table CSV/JSON and DXF export with exact circle/arc/line cutouts), Boss, Lip/Groove, Snap Fit, Rest, Manage and Assign Plastic Rules; Fold (bend along a sketch line); flanges meeting at a corner closed at any angle with the rule's gap; edge flanges with their own angle and height per edge in one feature; corner reliefs (notch, round, rectangular, tear) chosen by the rule; Convert to Sheet Metal from a solid or shelled body by its bend edges (flat faces, sharp bends) | in progress | 36 |
 | M11 | 2D drawings | deferred | — |
 | M12 | Release: cross-platform packages, verification and deliberate publication implemented; original current-UI demo refreshed. Trusted distribution signing and broader performance work remain | in progress | 16 |