webots-kinova

Webots scene + RoboComp bridge for a fixed Kinova Gen3 7‑DoF arm with Robotiq 2F‑85 gripper mounted on a table. Pairs with the active-inference arm controller at robocomp/active_inference/kinova_controller.

Spawned from SergioEslava-UEx/webots-p3bot as a single-arm Kinova fork; the original mobile-robot bridge is preserved.

Layout

worlds/
  arm_table.wbt              # Kinova-on-table scene used by the controller
  …                          # other inherited p3bot scenes (legacy)
protos/
  KinovaGen3.proto           # the arm
  WaterBottleOpaque.proto    # opaque drop-in for Cyberbotics' WaterBottle
                             # so the bottle casts shadows in the renderer
  kinova_arm_meshes/         # STL meshes used both by Webots and by the
                             # active-inference viewer (ArmBeliefViewer3D
                             # in kinova_controller reads from here)
  …
components/
  kinova-bridge/             # RoboComp bridge: Webots ↔ Ice/CORTEX
    KinovaBridge.cdsl        # interfaces (KinovaArm, Camera360RGB, Lidar3D,
                             #             CameraRGBDSimple, OmniRobot,
                             #             Webots2Robocomp, …)
    src/specificworker.{h,cpp}

Build the bridge

cd components/kinova-bridge
cmake -B build && make -C build -j12

Binary lands in bin/KinovaBridge. Run with:

bin/KinovaBridge etc/config

etc/config declares the Ice endpoints (KinovaArm = "tcp -p 15005", Webots2Robocomp = "tcp -p 15010", …); the kinova_controller agent's Proxies.* need to match these.

Webots side

Open worlds/arm_table.wbt. The P3Bot Robot node is the supervisor that hosts the KinovaGen3 PROTO (controller <extern>, so the bridge process above drives it). The bottle uses WaterBottleOpaque rather than upstream WaterBottle because Webots' shadow pass skips transparent geometry — see Why opaque? below.

Webots2Robocomp DEF resolution

Webots2Robocomp_getObjectPose("name") first tries getFromDef(name) and, on a miss, falls back to a one-shot scan of the world root's top-level children looking for a node whose SFString name field matches. This means world authors don't have to remember to add a DEF to every scene object they want supervised — setting the name field is enough.

Resolved nodes are cached (Node* pointers are stable in Webots).

Why opaque?

The upstream WaterBottle PROTO uses a textured IndexedFaceSet whose appearance pipeline makes the Webots shadow renderer skip it, so the bottle floats over the desk with no shadow. WaterBottleOpaque is a tiny PROTO (opaque PBRAppearance + Cylinder geometry, same interface fields: translation, rotation, name, mass, plus color, radius, height) that drops in cleanly and casts a real shadow.

Active-inference workflow

In tandem with kinova_controller:

1. Launch Webots and open worlds/arm_table.wbt.
2. Start bin/KinovaBridge etc/config from this repo.
3. Start kinova_controller's agent; the side-grasp loop hits the bottle's live world pose via Webots2Robocomp_getObjectPose("bottle").

Status

Active development. Bridge interfaces declared but several (Lidar3D, Camera360RGB, JoystickAdapter) are still scaffolds inherited from kinova-bridge; the Kinova side (KinovaArm + Webots2Robocomp) is the path currently exercised by kinova_controller.