release v0.2.0

CHANGELOG.md

@@ -1,5 +1,73 @@
 # Changelog
 
+## v0.2.0
+
+### Forward projection
+
+- `BicycleProjector` — ramps the steering angle toward a target at a bounded rate, clamped to
+  `[min, max]`, and integrates pose with Euler. Pose reference is the rear axle.
+- `ArticulatedProjector` — same shape for the articulation angle γ and rate γ̇. Pose reference
+  (`base_link`) is the articulation joint; motion is integrated at the rear axle and converted
+  back to the joint each step.
+- `DifferentialDriveProjector` — ramps the body command (v, ω) toward a target under separate
+  linear and angular acceleration limits. Pose reference is the body centre.
+- All three expose `step()` for one time step and `project()` for a full horizon, returning a
+  timestamped state sequence whose element 0 is the initial state.
+
+### Footprints
+
+- `Pose2D`, `Point2D`, and `Footprint` (a counter-clockwise, unclosed polygon of any vertex count)
+  in a shared `pose2d.hpp`, along with `normalizeAngle`, `transformFootprint`,
+  `offsetAlongHeading`, and `rectangleFootprint` for the boxy common case.
+- Each projector optionally takes an **arbitrary body-frame polygon** and emits it transformed into
+  the world frame per sample; the kinematic models stay dimension-free. An empty polygon means
+  "unset" and yields an empty footprint rather than throwing. The articulated projector takes one
+  polygon per body.
+
+### Axle reference
+
+- `AxleReference::FRONT` / `REAR` selects the axle that `BicycleProjector` and
+  `ArticulatedProjector` measure poses and footprints from. Motion is still integrated where each
+  model is naturally defined (the rear axle); the reference conversion is applied on input and
+  output, so no integration accuracy is traded for the choice.
+- For the articulated model, `theta` follows the referenced axle's body — $\theta_r$ for REAR,
+  $\theta_f = \theta_r + \gamma$ for FRONT — and each body's polygon is anchored at **its own**
+  axle, the only anchoring that stays rigid as the joint articulates.
+- `ArticulatedProjectedState` gained `joint_pose`, so the articulation joint (`base_link`) is
+  reported on every sample whichever axle is referenced.
+- A differential drive has one axle, so `DifferentialDriveProjector` takes no reference; its
+  polygon is measured from the body centre.
+
+### Kinematics
+
+- `ArticulatedModel` now accepts an explicit articulation turning velocity (γ̇) on
+  `bodyVelocityToVehicleState` and `articulationToAxleVelocities`. The previous two-argument
+  forms remain as overloads that assume steady articulation (γ̇ = 0), so existing callers are
+  unaffected. γ̇ was previously a hardcoded zero constant.
+
+### Packaging
+
+- Wheel build via scikit-build-core, alongside the existing ROS2/ament path. One
+  `CMakeLists.txt` serves both; `find_package(ament_cmake QUIET)` selects the branch. The wheel
+  links the C++ library statically so it ships a single `.so`.
+- Python bindings for all three projectors, their projected-state structs, `Pose2D`, and
+  `Point2D`.
+
+### Kinematic Explorer
+
+- New Streamlit app (`kinematic-explorer`) for visualising trajectory lattices, kinematic
+  relationships, and vehicle footprints across all three models. Every trajectory it draws
+  comes from the C++ projectors, so the explorer and production code share one
+  forward-simulation path.
+- Geometry sliders (including body overhangs), a front/rear axle reference selector,
+  single-projected-trajectory ramp controls, and CSV / JSON / PNG / SVG / PDF download.
+
+### Removed
+
+- `Twist2D`, `normalize_angle`, and `transform_pose` from the Python package — leftovers from
+  when `Pose2D` was a Python shim, now superseded by the bound C++ `Pose2D` and
+  `normalizeAngle`.
+
 ## v0.1.0
 
 Initial release.

package.xml

@@ -2,7 +2,7 @@
 <?xml-model href="http://download.ros.org/schema/package_format3.xsd" schematypens="http://www.w3.org/2001/XMLSchema"?>
 <package format="3">
   <name>polymath_kinematics</name>
-  <version>0.1.0</version>
+  <version>0.2.0</version>
   <description>Mixed C++/Python kinematics library for vehicle models</description>
   <maintainer email="engineering@polymathrobotics.com">Polymath Engineering</maintainer>
   <license>Apache-2.0</license>