Robotics evidence guide · automated editorial preparation, not expert review

Worked example: reviewing a ROS bag intake manifest

Begin with an offline inventory of a recording’s streams, time basis and gaps. A ROS bag is a recording container, not a complete robotics evidence package.

Evidence and interpretation

rosbag2 documents metadata inspection and playback ordering. The following is a Maha-authored synthetic intake walkthrough, not an implemented bag parser. Suppose an inventory declares joint states, commands and camera observations for a registered trial. Before replay, compare that inventory with required observations and preserve unknowns. Do not publish a recording to a live robot network merely to inspect it. The example stays at the manifest level and issues no commands.

Proposed evidence workflow

  1. Identify the supplied recording and its format/version; inspect authorized metadata offline.
  2. Map expected streams to observed streams and record timestamp semantics and recording gaps.
  3. Produce a sanitized intake disposition; keep playback, physical interpretation and release authorization separate.

Worked illustration

Synthetic intake A contains command and joint-state streams but omits the required camera stream. Disposition: revise for outcome evidence; commands alone do not prove receipt of an object. Intake B supplies the camera stream but no relation between its capture clock and the outcome clock. Its time-dependent conclusion remains unresolved. Neither case is passed by merely hashing the manifest.

Limits

These are manually worked cases. No MCAP/DB3 parser, ROS process, device connection or real recording was executed. The fixed grid verifier does not accept ROS bags.

Sources and review

ROS 2 rosbag2 documentation

Locator: README: Statistics about lost messages; Replaying data; Analyzing data

rosbag2 records and replays messages; playback can order by reception or publication timestamps and expose recording statistics.

Boundary: These capabilities do not guarantee identical controller execution or complete physical observation.

Inspection and reuse basis

Selected sections inspected 2026-09-14. Original explanation and link; no code or logs copied. This is not independent expert review of this article.

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