Menlo
Python SDKGuides

Record a Session

Capture every state sample and every command as JSON lines.

Wrap any run and get a file you can replay, plot, or attach to a bug report:

with robot.record("run.jsonl") as rec:
    robot.stand()
    robot.wait_for(Mode.STAND, timeout=20.0)
    robot.set_velocity(vx=0.3, duration=4.0, wait=True)
    robot.stop()
rec.samples, rec.commands_written

Every state sample the robot sent and every command your script sent lands in run.jsonl, one JSON object per line, in order. Nothing is sampled or averaged.

It is a context manager: recording stops when the block exits, including when it exits because of an exception — which is exactly the run you want the file for.

from menlo.asimov import recording
for row in recording.load("run.jsonl"):     # dicts with kind "state" | "sent"
    ...

What It Is Good For

  • Bug reports. A refusal or a fall is much easier to read from the log than to describe.
  • Comparing runs. The same script against the simulator and against hardware gives two files with the same shape.
  • Checking your loop. Command timestamps show whether your control loop actually held its rate.

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How is this guide?

Camera and Audio

Frames, microphone, speaker and clips — over the robot's LiveKit room.

Safety

The rules that decide whether the robot stays upright — and what stops it when your code doesn't.

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What It Is Good For
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