Recording Data

SDK Practice

Overview

The public 2.recording.py example uses TopicRecorder to save Wuji Glove streams to an MCAP file.

This page uses Python. For C SDK recording, see Recording Examples.

Prerequisites

Complete the device connections and network setup in Wuji Glove Getting Started.
Install Wuji SDK. For environment requirements, see the Wuji SDK Quick Start.

Example Configuration

Item	Setting
Device	The first Wuji Glove in the scan results
Streams	`tactile`, `emf_poses`, and `hand_skeleton`
Compression	`lz4`
Recording duration	10 seconds
Output file	`./data/YYYYMMDD_HHMMSS.mcap`, named with the date and time when recording starts

Integration Steps

The following snippets run inside async def main() in the public example. See the example file for imports and the complete control flow.

Connect the Device

The example calls manager.scan(), filters for DeviceType.WujiGlove, and connects to the first glove by serial number. If no device or glove is found, it prints a message and exits.

Register the Channels

Create a recorder and register three device streams:

recorder = TopicRecorder(compression="lz4")
recorder.record(glove.tactile().subscribe())
recorder.record(glove.emf_poses().subscribe())
recorder.record(glove.hand_skeleton().subscribe())

Start Recording

Create the output directory, generate a timestamped filename, and start recording:

os.makedirs("./data", exist_ok=True)
path = f"./data/{datetime.now().strftime('%Y%m%d_%H%M%S')}.mcap"
handle = await recorder.start(path)

Stop and Clean Up

After 10 seconds, call handle.stop(). If the task is cancelled, asyncio.shield() protects the stop task, and the example waits for it to finish:

try:
    await asyncio.sleep(10)
finally:
    stop_task = asyncio.ensure_future(handle.stop())
    try:
        summary = await asyncio.shield(stop_task)
    except asyncio.CancelledError:
        summary = await stop_task

The outer finally block calls manager.disconnect_all() to disconnect the device.

Running It

Run the following command from the root of the public wuji-sdk repository:

python examples/python/wuji_glove/2.recording.py

The program prints the discovered devices, the connected glove’s serial number, and the output path. When recording ends, the Done line shows these results:

Field	Output
`summary.total_frames`	Total frames in this recording
`summary.file_size`	Size of the recorded file
`summary.duration_s`	Duration of this recording

Open the MCAP file with Foxglove Studio or inspect it with mcap info.