docs: 规划ACT相机预览与质量判定修正

2026-08-13 22:09:53 +08:00
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+# ACT 双相机预览与采样质量判定修正实施计划
+
+> **供代理执行者使用：** 必须使用 `superpowers:subagent-driven-development`（推荐）或 `superpowers:executing-plans`，逐项执行本计划。所有步骤使用复选框（`- [ ]`）跟踪。
+
+**目标：** 保持 ACT 当前因果时间对齐，同时把真实相机丢帧与软件采样相位漂移分开判定，并在 ACT 数采启动时默认显示全局 D455 和右腕 D405 实时画面。
+
+**架构：** 继续由 `act_episode_recorder` 独占两台 RealSense，并按每三个 `90 Hz` 控制周期选择不晚于控制时刻的最新图像。`CameraBuffer` 负责真实采集质量，HDF5 校验只记录 ACT 样本重复/跨帧率；同一节点内新增一个只读 OpenCV 预览线程，复用现有帧缓冲且不进入机器人控制链路。
+
+**技术栈：** Ubuntu 22.04、ROS2 Humble、Python 3、rclpy、NumPy、h5py、pyrealsense2、OpenCV、pytest、HDF5。
+
+---
+
+## 文件结构
+
+本次不新建 ROS 包或运行进程，文件职责保持如下：
+
+- 修改 `xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py`：真实采集统计、ACT 采样相位指标、质量判定、双路预览及关闭顺序；
+- 修改 `xr_rm_teleop/test/test_act_episode_recorder.py`：指标口径、误拒绝复现、帧号回退和预览隔离测试；
+- 修改 `README.md`：说明 ACT 数采默认预览、显示内容和关闭行为。
+
+不修改 `arm_debug.launch.py`、`launcher_ui.py`、ROS 消息、机器人控制节点和相机 YAML。工作区已有的 `xr_rm_teleop/xr_rm_teleop/fun_peripheral.py` 未提交改动属于用户，不加入本任务提交。
+
+所有构建和测试命令从工作空间根目录执行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+```
+
+自动化测试不得启动真机 launch、移动机械臂或操作夹爪。
+
+### 任务 1：区分真实丢帧与 ACT 采样相位漂移
+
+**文件：**
+
+- 修改：`xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py:408-579`
+- 修改：`xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py:595-657`
+- 修改：`xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py:1472-1511`
+- 测试：`xr_rm_teleop/test/test_act_episode_recorder.py:273-296`
+- 测试：`xr_rm_teleop/test/test_act_episode_recorder.py:491-607`
+
+- [ ] **步骤 1：写异步采样不拒绝和指标测试**
+
+在测试导入中加入 `sample_frame_metrics`，并增加：
+
+```python
+def test_sample_frame_metrics_separate_repeats_skips_and_regressions():
+    repeat, skip, regression = sample_frame_metrics(
+        np.asarray((986, 986, 988), dtype=np.uint64)
+    )
+
+    assert repeat == pytest.approx(0.5)
+    assert skip == pytest.approx(0.5)
+    assert regression == 0
+
+
+@requires_h5py
+def test_validate_episode_accepts_async_camera_phase_drift(tmp_path):
+    path = _valid_episode(tmp_path)
+    with h5py.File(path, "r+") as root:
+        root["debug/cameras/cam_high_frame_number"][:] = (986, 986, 988)
+
+    report = validate_episode(path, _quality_limits())
+
+    assert report.accepted
+    assert report.metrics["cam_high_sample_repeat_ratio"] == pytest.approx(0.5)
+    assert report.metrics["cam_high_sample_skip_ratio"] == pytest.approx(0.5)
+```
+
+在 `_valid_episode()` 写入新增的真实采集属性：
+
+```python
+root.attrs["camera_high_frame_number_regression_count"] = 0
+root.attrs["camera_right_wrist_frame_number_regression_count"] = 0
+```
+
+- [ ] **步骤 2：写真实帧号回退测试**
+
+扩展现有 `CameraBuffer` 测试：
+
+```python
+def test_camera_buffer_counts_frame_number_regressions():
+    buffer = CameraBuffer(maxlen=4)
+    for frame_number in (100, 101, 1, 2):
+        buffer.push(
+            CameraFrame(
+                _image(frame_number),
+                frame_number,
+                float(frame_number),
+                time.monotonic_ns(),
+            )
+        )
+
+    stats = buffer.stats()
+
+    assert stats.frame_number_regression_count == 1
+    assert stats.dropped_frames == 0
+```
+
+测试文件顶部增加标准库导入：
+
+```python
+import time
+```
+
+并在稳定拒绝原因参数中增加真实采集帧号回退：
+
+```python
+elif mutation == "camera_frame_regression":
+    root.attrs["camera_high_frame_number_regression_count"] = 1
+```
+
+对应期望：
+
+```python
+("camera_frame_regression", "camera_frame_number_regression"),
+```
+
+- [ ] **步骤 3：运行新增测试并确认失败**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+pytest src/xr_rm_teleop/test/test_act_episode_recorder.py \
+  -k "sample_frame_metrics or async_camera_phase_drift or frame_number_regressions or camera_frame_regression" -v
+```
+
+预期：测试因 `sample_frame_metrics` 尚不存在、`CameraStats` 没有回退计数，或旧校验仍以 `camera_sample_drop_ratio` 拒绝而失败。
+
+- [ ] **步骤 4：实现最小采样相位指标**
+
+在质量校验辅助函数附近增加纯函数：
+
+```python
+def sample_frame_metrics(
+    frame_numbers: np.ndarray,
+) -> tuple[float, float, int]:
+    diffs = np.diff(np.asarray(frame_numbers, dtype=np.int64))
+    denominator = max(1, len(diffs))
+    return (
+        float(np.count_nonzero(diffs == 0) / denominator),
+        float(np.count_nonzero(diffs > 1) / denominator),
+        int(np.count_nonzero(diffs < 0)),
+    )
+```
+
+把 `validate_episode()` 中原有“所有 `diff != 1` 都拒绝”的循环替换为：
+
+```python
+for camera in ("cam_high", "cam_wrist"):
+    frame_numbers = datasets[
+        f"debug/cameras/{camera}_frame_number"
+    ][:]
+    repeat_ratio, skip_ratio, regression_count = sample_frame_metrics(
+        frame_numbers
+    )
+    metrics[f"{camera}_sample_repeat_ratio"] = repeat_ratio
+    metrics[f"{camera}_sample_skip_ratio"] = skip_ratio
+    if regression_count:
+        return _quality_failure("camera_frame_number_regression", metrics)
+```
+
+这样 `986 → 986 → 988` 只产生统计，不再触发 `camera_sample_drop_ratio`。
+
+- [ ] **步骤 5：在采集层统计帧号回退**
+
+扩展 `CameraStats`：
+
+```python
+@dataclass(frozen=True)
+class CameraStats:
+    frame_count: int
+    dropped_frames: int
+    frame_number_regression_count: int
+    first_host_monotonic_ns: int | None
+    last_host_monotonic_ns: int | None
+```
+
+在 `CameraBuffer.__init__()` 增加：
+
+```python
+self._frame_number_regression_count = 0
+```
+
+在 `CameraBuffer.push()` 更新帧号前使用互斥分支：
+
+```python
+if self._last_frame_number is not None:
+    if frame.frame_number <= self._last_frame_number:
+        self._frame_number_regression_count += 1
+    elif frame.frame_number > self._last_frame_number + 1:
+        self._dropped_frames += (
+            frame.frame_number - self._last_frame_number - 1
+        )
+```
+
+在 `stats()` 返回：
+
+```python
+frame_number_regression_count=self._frame_number_regression_count,
+```
+
+- [ ] **步骤 6：把真实采集回退纳入 episode 属性和拒绝条件**
+
+把 `_interval_camera_metrics()` 的返回值扩展为 FPS、真实丢帧率和本 episode 新增的回退数：
+
+```python
+@staticmethod
+def _interval_camera_metrics(
+    baseline: CameraStats,
+    current: CameraStats,
+) -> tuple[float, float, int]:
+    frames = max(0, current.frame_count - baseline.frame_count)
+    dropped = max(0, current.dropped_frames - baseline.dropped_frames)
+    regressions = max(
+        0,
+        current.frame_number_regression_count
+        - baseline.frame_number_regression_count,
+    )
+    if (
+        baseline.last_host_monotonic_ns is None
+        or current.last_host_monotonic_ns is None
+    ):
+        return 0.0, 1.0, regressions
+    elapsed_ns = (
+        current.last_host_monotonic_ns
+        - baseline.last_host_monotonic_ns
+    )
+    fps = frames * 1e9 / elapsed_ns if elapsed_ns > 0 else 0.0
+    expected = frames + dropped
+    drop_ratio = dropped / expected if expected else 1.0
+    return fps, drop_ratio, regressions
+```
+
+`_write_camera_metrics()` 写入：
+
+```python
+"camera_high_frame_number_regression_count": high[2],
+"camera_right_wrist_frame_number_regression_count": wrist[2],
+```
+
+`validate_episode()` 在读取 FPS 和真实丢帧率后要求两个回退属性存在且为零：
+
+```python
+for name in (
+    "camera_high_frame_number_regression_count",
+    "camera_right_wrist_frame_number_regression_count",
+):
+    if name not in root.attrs:
+        return _quality_failure("camera_stats_missing", metrics)
+    value = int(root.attrs[name])
+    metrics[name] = value
+    if value:
+        return _quality_failure("camera_frame_number_regression", metrics)
+```
+
+- [ ] **步骤 7：确保采样指标写入保存和拒绝文件**
+
+增加读取 HDF5 根节点的辅助函数：
+
+```python
+def episode_sample_frame_metrics(root: Any) -> dict[str, int | float]:
+    metrics: dict[str, int | float] = {}
+    for camera in ("cam_high", "cam_wrist"):
+        repeat, skip, regression = sample_frame_metrics(
+            root[f"debug/cameras/{camera}_frame_number"][:]
+        )
+        metrics[f"{camera}_sample_repeat_ratio"] = repeat
+        metrics[f"{camera}_sample_skip_ratio"] = skip
+        metrics[f"{camera}_sample_frame_number_regression_count"] = regression
+    return metrics
+```
+
+`validate_episode()` 复用该函数更新 `report.metrics`。在 `_reject_closed_partial()` 已打开 HDF5 后也执行：
+
+```python
+for name, value in episode_sample_frame_metrics(root).items():
+    root.attrs[name] = value
+```
+
+保存路径继续由 `_complete_save()` 把 `report.metrics` 写入属性。保存日志追加紧凑摘要：
+
+```python
+self.get_logger().info(
+    "ACT相机采样相位："
+    f"high重复={report.metrics['cam_high_sample_repeat_ratio']:.2%}, "
+    f"high跨帧={report.metrics['cam_high_sample_skip_ratio']:.2%}, "
+    f"wrist重复={report.metrics['cam_wrist_sample_repeat_ratio']:.2%}, "
+    f"wrist跨帧={report.metrics['cam_wrist_sample_skip_ratio']:.2%}"
+)
+```
+
+- [ ] **步骤 8：运行相关测试并确认通过**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+pytest src/xr_rm_teleop/test/test_act_episode_recorder.py \
+  -k "camera or validate_episode" -v
+```
+
+预期：所有选中测试通过；真实丢帧率仍使用 `camera_drop_ratio` 拒绝，异步重复/跨帧不拒绝。
+
+- [ ] **步骤 9：提交任务 1**
+
+```bash
+git add src/xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py \
+  src/xr_rm_teleop/test/test_act_episode_recorder.py
+git commit -m "fix: 修正ACT相机采样质量判定"
+```
+
+### 任务 2：在录制器中增加非阻塞双路预览
+
+**文件：**
+
+- 修改：`xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py:595-657`
+- 修改：`xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py:1006-1152`
+- 修改：`xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py:1668-1671`
+- 测试：`xr_rm_teleop/test/test_act_episode_recorder.py`
+
+- [ ] **步骤 1：写两秒滚动 FPS 测试**
+
+扩展 `CameraBuffer` 测试，使用明确的单调时间：
+
+```python
+def test_camera_buffer_reports_two_second_rolling_fps():
+    buffer = CameraBuffer(maxlen=4)
+    start_ns = 10_000_000_000
+    for index in range(61):
+        buffer.push(
+            CameraFrame(
+                _image(index),
+                index,
+                float(index),
+                start_ns + index * 33_333_333,
+            )
+        )
+
+    assert buffer.stats().rolling_fps == pytest.approx(30.0, rel=0.02)
+```
+
+- [ ] **步骤 2：写预览显示异常隔离测试**
+
+构造不经过 ROS 初始化的录制器和抛错的 `cv2` 替身：
+
+```python
+def test_preview_failure_does_not_change_recording_state():
+    recorder = object.__new__(ActEpisodeRecorder)
+    recorder._session = _recording_session()
+    recorder._preview_stop = threading.Event()
+    recorder._preview_thread = None
+    recorder.get_logger = lambda: _Logger()
+
+    class FailingCv2:
+        WINDOW_NORMAL = 0
+
+        @staticmethod
+        def namedWindow(*_args):
+            raise RuntimeError("no display")
+
+    recorder._preview_loop(FailingCv2())
+
+    assert recorder.state is RecordingState.RECORDING
+```
+
+`_Logger` 增加 `warns` 收集和 `warn()`：
+
+```python
+self.warns = []
+
+def warn(self, message):
+    self.warns.append(message)
+```
+
+- [ ] **步骤 3：写预览关闭顺序测试**
+
+验证关闭节点时先停预览，再停相机：
+
+```python
+def test_close_stops_preview_before_cameras_and_releases_lock():
+    events = []
+    recorder = object.__new__(ActEpisodeRecorder)
+    recorder._stop_preview = lambda: events.append("preview")
+    recorder._high_camera = SimpleNamespace(
+        stop=lambda: events.append("high")
+    )
+    recorder._wrist_camera = SimpleNamespace(
+        stop=lambda: events.append("wrist")
+    )
+    recorder._directory_lock = SimpleNamespace(
+        release=lambda: events.append("lock")
+    )
+
+    recorder.close()
+
+    assert events == ["preview", "high", "wrist", "lock"]
+```
+
+- [ ] **步骤 4：运行新增预览测试并确认失败**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+pytest src/xr_rm_teleop/test/test_act_episode_recorder.py \
+  -k "rolling_fps or preview or close_stops_preview" -v
+```
+
+预期：测试因 `rolling_fps`、`_preview_loop()` 和 `_stop_preview()` 尚不存在而失败。
+
+- [ ] **步骤 5：实现两秒滚动 FPS**
+
+在 `CameraBuffer.__init__()` 增加：
+
+```python
+self._recent_host_monotonic_ns: deque[int] = deque()
+```
+
+每次 `push()` 时裁剪两秒窗口：
+
+```python
+self._recent_host_monotonic_ns.append(frame.host_monotonic_ns)
+cutoff_ns = frame.host_monotonic_ns - 2_000_000_000
+while (
+    self._recent_host_monotonic_ns
+    and self._recent_host_monotonic_ns[0] < cutoff_ns
+):
+    self._recent_host_monotonic_ns.popleft()
+```
+
+`CameraStats` 增加字段和属性：
+
+```python
+recent_host_monotonic_ns: tuple[int, ...]
+
+@property
+def rolling_fps(self) -> float:
+    if len(self.recent_host_monotonic_ns) < 2:
+        return 0.0
+    elapsed_ns = (
+        self.recent_host_monotonic_ns[-1]
+        - self.recent_host_monotonic_ns[0]
+    )
+    return (
+        (len(self.recent_host_monotonic_ns) - 1) * 1e9 / elapsed_ns
+        if elapsed_ns > 0
+        else 0.0
+    )
+```
+
+`stats()` 使用：
+
+```python
+recent_host_monotonic_ns=tuple(self._recent_host_monotonic_ns),
+```
+
+- [ ] **步骤 6：实现最小预览渲染方法**
+
+在 `ActEpisodeRecorder` 增加固定窗口名：
+
+```python
+PREVIEW_WINDOW = "ACT - D455 Global / D405 Right Wrist"
+```
+
+增加生成单个画面块的方法。相机帧是 RGB，因此显示前转换成 BGR：
+
+```python
+@staticmethod
+def _preview_tile(role: str, frame, stats, cv2):
+    if frame is None:
+        tile = np.zeros((480, 640, 3), dtype=np.uint8)
+        frame_number = "-"
+    else:
+        tile = cv2.cvtColor(frame.image, cv2.COLOR_RGB2BGR)
+        frame_number = str(frame.frame_number)
+    tile = tile.copy()
+    cv2.rectangle(tile, (0, 0), (640, 74), (0, 0, 0), -1)
+    lines = (
+        f"{role}  FPS {stats.rolling_fps:.1f}  Frame {frame_number}",
+        f"Received {stats.frame_count}  Dropped "
+        f"{stats.dropped_frames} ({stats.drop_ratio:.2%})",
+    )
+    for index, line in enumerate(lines):
+        cv2.putText(
+            tile,
+            line,
+            (10, 28 + index * 30),
+            cv2.FONT_HERSHEY_SIMPLEX,
+            0.65,
+            (255, 255, 255),
+            1,
+            cv2.LINE_AA,
+        )
+    return tile
+```
+
+增加 `_compose_preview()`：读取两个缓冲最新帧，水平拼接，并在底部显示状态：
+
+```python
+def _compose_preview(self, cv2):
+    high_frames = self._high_camera.buffer.snapshot()
+    wrist_frames = self._wrist_camera.buffer.snapshot()
+    high = high_frames[-1] if high_frames else None
+    wrist = wrist_frames[-1] if wrist_frames else None
+    high_stats = self._high_camera.buffer.stats()
+    wrist_stats = self._wrist_camera.buffer.stats()
+    image = np.hstack(
+        (
+            self._preview_tile("GLOBAL D455", high, high_stats, cv2),
+            self._preview_tile("RIGHT WRIST D405", wrist, wrist_stats, cv2),
+        )
+    )
+
+    now_ns = self._now_ns()
+    high_age = (
+        f"{(now_ns - high.host_monotonic_ns) * 1e-6:.1f} ms"
+        if high is not None
+        else "-"
+    )
+    wrist_age = (
+        f"{(now_ns - wrist.host_monotonic_ns) * 1e-6:.1f} ms"
+        if wrist is not None
+        else "-"
+    )
+    skew = (
+        f"{abs(high.host_monotonic_ns - wrist.host_monotonic_ns) * 1e-6:.1f} ms"
+        if high is not None and wrist is not None
+        else "-"
+    )
+    episode = (
+        f"episode_{self._episode_index}"
+        if self._episode_index is not None
+        else "-"
+    )
+    samples = self._store.count if self._store is not None else 0
+    footer = np.zeros((80, image.shape[1], 3), dtype=np.uint8)
+    lines = (
+        f"Age high={high_age} wrist={wrist_age}  Camera skew={skew}",
+        f"ACT {self.state.value}  {episode}  Samples {samples}",
+    )
+    for index, line in enumerate(lines):
+        cv2.putText(
+            footer,
+            line,
+            (10, 30 + index * 32),
+            cv2.FONT_HERSHEY_SIMPLEX,
+            0.7,
+            (255, 255, 255),
+            1,
+            cv2.LINE_AA,
+        )
+    return np.vstack((image, footer))
+```
+
+若尚无帧，对应数值显示 `-`；该方法不修改任何录制器状态。
+
+- [ ] **步骤 7：实现预览线程生命周期和故障隔离**
+
+在相机成员创建前初始化：
+
+```python
+self._preview_stop = threading.Event()
+self._preview_thread: threading.Thread | None = None
+```
+
+两台相机成功启动后调用 `_start_preview()`：
+
+```python
+if self._camera_start_error is None:
+    self._start_preview()
+```
+
+实现：
+
+```python
+def _start_preview(self) -> None:
+    if not (os.environ.get("DISPLAY") or os.environ.get("WAYLAND_DISPLAY")):
+        self.get_logger().warn("未检测到桌面显示环境，ACT双相机预览已停用。")
+        return
+    try:
+        import cv2
+    except ImportError as exc:
+        self.get_logger().warn(f"OpenCV不可用，ACT双相机预览已停用：{exc}")
+        return
+    self._preview_stop.clear()
+    self._preview_thread = threading.Thread(
+        target=self._preview_loop,
+        args=(cv2,),
+        name="act_camera_preview",
+        daemon=True,
+    )
+    self._preview_thread.start()
+
+def _preview_loop(self, cv2) -> None:
+    try:
+        cv2.namedWindow(self.PREVIEW_WINDOW, cv2.WINDOW_NORMAL)
+        while not self._preview_stop.is_set():
+            cv2.imshow(self.PREVIEW_WINDOW, self._compose_preview(cv2))
+            key = cv2.waitKey(1) & 0xFF
+            if key in (ord("q"), ord("Q"), 27):
+                break
+            if cv2.getWindowProperty(
+                self.PREVIEW_WINDOW,
+                cv2.WND_PROP_VISIBLE,
+            ) < 1:
+                break
+            self._preview_stop.wait(0.1)
+    except Exception as exc:
+        self.get_logger().warn(f"ACT双相机预览已停用：{exc}")
+    finally:
+        try:
+            cv2.destroyWindow(self.PREVIEW_WINDOW)
+        except Exception:
+            pass
+
+def _stop_preview(self) -> None:
+    self._preview_stop.set()
+    if self._preview_thread is not None:
+        self._preview_thread.join(timeout=2.0)
+    self._preview_thread = None
+```
+
+`close()` 的第一步调用 `self._stop_preview()`，然后保持现有相机停止和目录锁释放顺序。
+
+- [ ] **步骤 8：运行预览相关测试并确认通过**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+pytest src/xr_rm_teleop/test/test_act_episode_recorder.py \
+  -k "rolling_fps or preview or close_stops_preview" -v
+```
+
+预期：所有选中测试通过，测试过程不打开真实窗口或相机。
+
+- [ ] **步骤 9：运行 ACT 录制器完整单元测试**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+pytest src/xr_rm_teleop/test/test_act_episode_recorder.py -v
+```
+
+预期：全部通过。
+
+- [ ] **步骤 10：提交任务 2**
+
+```bash
+git add src/xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py \
+  src/xr_rm_teleop/test/test_act_episode_recorder.py
+git commit -m "feat: 添加ACT双相机实时预览"
+```
+
+### 任务 3：更新使用说明并完成工作空间验证
+
+**文件：**
+
+- 修改：`README.md:144-169`
+
+- [ ] **步骤 1：更新 ACT 数采说明**
+
+在 ACT episode 启动命令后补充：
+
+```markdown
+`record_act:=true` 启动后默认显示全局 D455 和右腕 D405 双路画面，并显示实时
+FPS、真实丢帧率、帧龄、双相机时间差、录制状态、episode 编号和样本数。按
+`Q`、`Esc` 或关闭窗口只会停止预览，ACT 相机采集和录制继续运行；没有桌面环境
+或 OpenCV 显示失败时也不会影响录制。
+
+相机采集线程观察到的真实掉帧仍会拒绝 episode。独立 `30 Hz` 控制和相机时钟
+造成的 ACT 样本重复/跨帧只写入 HDF5 质量指标，不再误报为相机丢包。
+```
+
+- [ ] **步骤 2：运行文档和 Python 静态检查**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+python -m py_compile \
+  src/xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py \
+  src/xr_rm_teleop/test/test_act_episode_recorder.py
+git diff --check
+```
+
+预期：命令返回码为 `0`，没有语法或空白错误。
+
+- [ ] **步骤 3：运行项目要求的工作空间构建**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+colcon build --symlink-install
+```
+
+预期：所有包构建成功。不得在 `/home/robot/WS_xr/src` 中运行该命令。
+
+- [ ] **步骤 4：构建后再次运行 ACT 录制器测试**
+
+运行：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+source install/setup.bash
+pytest src/xr_rm_teleop/test/test_act_episode_recorder.py -v
+```
+
+预期：全部通过。
+
+- [ ] **步骤 5：确认提交范围并提交任务 3**
+
+运行：
+
+```bash
+git status --short
+git diff -- README.md \
+  src/xr_rm_teleop/xr_rm_teleop/act_episode_recorder.py \
+  src/xr_rm_teleop/test/test_act_episode_recorder.py
+git add README.md
+git commit -m "docs: 更新ACT相机预览说明"
+```
+
+不得暂存或提交 `xr_rm_teleop/xr_rm_teleop/fun_peripheral.py`。
+
+## 现场验证
+
+自动化实施结束后，由用户在确认现场安全条件后运行现有 ACT 数采入口：
+
+```bash
+cd /home/robot/WS_xr
+source /opt/ros/humble/setup.bash
+source install/setup.bash
+ros2 launch xr_rm_bringup arm_debug.launch.py \
+  arm:=right use_mock:=false record_act:=true
+```
+
+该命令会连接右臂真机，代理不得自行执行。现场确认：
+
+1. 双路画面默认出现且角色正确；
+2. FPS、真实丢帧率、帧龄、双相机时间差和 ACT 状态持续更新；
+3. 关闭窗口后录制状态和 HDF5 写入继续；
+4. 正常异步重复/跨帧的 episode 能保存；
+5. HDF5 属性包含真实采集质量与两路采样重复/跨帧指标。