{
  "payloads": {
    "audio_left_tone": {
      "modality": "audio",
      "signal": {"id": "witness_left_tone", "kind": "tone", "ms": 240, "hz": 180, "sweep": 0, "amp": 0.4}
    },
    "vision_corner": {
      "modality": "vision",
      "signal": {"id": "witness_corner", "kind": "corner", "size": 32}
    },
    "sensorimotor_contact": {
      "modality": "sensorimotor",
      "signal": {
        "id": "witness_contact",
        "pose_q": [10, -4, 3],
        "velocity_q": [1, 0, -1],
        "force_torque_q": [2, 3, 5],
        "contact_q": [1, 0, 1, 0],
        "actuator_state_q": [7, 8]
      }
    }
  }
}