motion-control

name: motion-control description: | Executable robot-dog motion-control MVP for leg IK, gait phase generation, trajectory contracts, controller parameters, and simulation/firmware handoff. Use this skill when the user asks for FK/IK, inverse kinematics, gait generator, trot/walk/bound trajectories, controller parameters, motion-control code, or a trajectory to feed simulation, MuJoCo, or firmware.

This skill turns robot-dog kinematics and gait intent into machine-readable motion artifacts. The MVP implements deterministic 2-link sagittal IK and simple phase-based gait trajectories. It is a file-contract layer, not a full MPC/WBC controller.

When To Use

Use this skill for:

Checking whether foot targets are reachable by the leg geometry.
Generating initial trot/walk phase tables and joint trajectories.
Producing trajectory.json and controller_params.yaml for simulation or firmware.
Reporting IK blockers before gait/dynamics validation.

Workflow

Read <project>/motion_plan.yaml.
Solve IK targets against link lengths and joint limits.
Generate a phase-based gait trajectory for the requested gait.
Write reports and handoff files into <project>/reports/ and <project>/control/.

Commands

python skills/motion-control/scripts/solve_ik.py skills/motion-control/examples/quadruped_mvp
python skills/motion-control/scripts/generate_gait.py skills/motion-control/examples/quadruped_mvp

Rules

Keep MVP kinematics deterministic and conservative.
Treat unreachable required foot targets or joint-limit violations as blockers.
Keep output trajectory format compatible with simulation/viewer-style trajectory.json.
Do not claim this replaces full whole-body control, MPC, state estimation, or real-time firmware.
Do not import sibling subskill code. Read files only.

References

references/input-contract.md for motion_plan.yaml fields.
references/ik-model.md for MVP 2-link IK.
references/gait-contract.md for phase and trajectory output.
references/output-contract.md for report fields.
references/examples.md for sample project layout.