Logging¶

Per-cycle CSV logging of every exchanged variable, in its own process.

Usage¶

# Start logging (auto-generates filename in logs/)
path = api.logging.start()
print(path)  # logs/17-04-2026_14-32-45.csv

# Or specify filename
api.logging.start("my_experiment.csv")

api.logging.is_active()   # True
api.logging.stop()

Logs include British-format timestamps, all send/receive variables per cycle. Logging runs in a separate process to avoid interfering with the 4 ms control loop.

Reference¶

LoggingAPI ¶

LoggingAPI(client: RSIClient)

CSV data logging interface for KUKA RSI robot control.

Manages high-frequency data logging to CSV files with British date format timestamps. Logging runs in a separate process to avoid timing interference with the real-time control loop.

Initialize LoggingAPI namespace.

Parameters:

Name	Type	Description	Default
`client`	`RSIClient`	RSIClient instance for logging control	required

start ¶

start(filename: Optional[str] = None) -> str

Start CSV logging to file.

Creates a background logging process that writes send/receive variables to CSV with British date format timestamps (DD/MM/YYYY HH:MM:SS.mmm).

Parameters:

Name	Type	Description	Default
`filename`	`Optional[str]`	Optional output file path. Auto-generated if not provided with format: logs/DD-MM-YYYY_HH-MM-SS.csv	`None`

Returns:

Type	Description
`str`	Path to the log file being written

Example

Auto-generated filename¶

path = api.logging.start() print(path) logs/16-01-2026_14-32-45.csv

Custom filename¶

path = api.logging.start('my_experiment.csv') print(path) my_experiment.csv

Note

Logging runs in a separate process and uses a queue-based buffering system to prevent blocking the real-time control loop. If the queue fills, old entries are dropped rather than blocking.

stop ¶

stop() -> str

Stop CSV logging.

Signals the logging process to flush remaining data and close the file. The logging process will terminate gracefully.

Returns:

Type	Description
`str`	Status message

Example

api.logging.stop() 'CSV logging stopped'

Note

There may be a brief delay (up to 2 seconds) while the logging process completes writing buffered data and shuts down.

is_active ¶

is_active() -> bool

Check if CSV logging is currently running.

Returns:

Type	Description
`bool`	True if logging process is active and writing data

Example

api.logging.start('test.csv') api.logging.is_active() True api.logging.stop() api.logging.is_active() False

export ¶

export(filename: str = 'movement_log.csv', source: Optional[str] = None) -> str

Export the most recent recorded CSV log to a new file.

Copies the log recorded via start()/stop() (or an explicit source file) to the given destination — a snapshot you can hand off while later runs overwrite the working log.

Parameters:

Name	Type	Description	Default
`filename`	`str`	Output CSV file path	`'movement_log.csv'`
`source`	`Optional[str]`	Source log to export (default: the last file passed to start() in this session)	`None`

Returns:

Type	Description
`str`	Status message with export path

Raises:

Type	Description
`RuntimeError`	If no log has been recorded this session and no source was given
`FileNotFoundError`	If the source log file does not exist

Example

api.logging.start('logs/run1.csv')

... motion ...¶

api.logging.stop() api.logging.export('run1_snapshot.csv') 'Movement data exported to run1_snapshot.csv'