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name: robot-models description: "Build cuRobo robot models from YAML or URDF, inspect joint and tool-frame contracts, and run CUDA forward kinematics with differentiable batched tensors." disable-model-invocation: true metadata: disco-role: operating license: NOASSERTION

Robot models and kinematics

Use this route for URDF/YAML loading, robot builder decisions, joint-name or link-frame debugging, FK/Jacobian queries, robot spheres, and pose/state tensor construction. Read api-reference.md for verified signatures and robot-builder.md for URDF and sphere-approximation workflow choices.

Core workflow

1. Select a bundled robot config and its tool frame; verify URDF, joint names, limits, collision spheres, and tool_frames are coherent.
2. Build KinematicsCfg with from_robot_yaml_file(...), supplying a DeviceCfg when the default CUDA device is not appropriate. Construct Kinematics only after a CUDA tensor probe succeeds.
3. Create (B, dof) float32 positions with JointState.from_position(q, joint_names=kin.joint_names). Call compute_kinematics and inspect tool_poses, link poses, and Jacobians in the returned KinematicsState.
4. For reachability or optimization, pass a batch of configurations; retain requires_grad=True when differentiating a scalar loss through FK.
5. Use scripts/fk_smoke.py for a bounded CUDA sanity check; it intentionally avoids benchmark timing and interactive visualization.

Use troubleshooting.md when a YAML, URDF, frame, device, quaternion, or shape error appears. Collision-aware consumers continue in collision-scenes, and target solving continues in ik.