feat(pybot×actpred): R2 姿态反馈方案一——MPU6050 独立 IMU token 全链路

- pybot：recorder 逐帧落盘 imu.npy（T×8，roll,pitch,ax,ay,az,gx,gy,gz，与帧/动作同调用对齐）；run_loop 对声明 imu_dim 的 predictor 以 predict(..., imu=) 调用（鸭子类型，旧两参调用向后兼容）

- actpred：新增 --imu-dim；model 序列 [img×F, act×H, (IMU), PRED]（imu_dim>0 时 F+H+2，IMU token 位于 PRED 前）；dataset/train 读 imu.npy（缺失按零向量兜底）；predict/ONNX/Hailo 三后端与 export/gen_calibration/dfc_compile/_npu_test 部署链适配 imu 输入

- 姿态按物理量程固定缩放归一化（imu_norm.py，训练/推理共用，零状态）

- 测试：actpred 128 passed / pybot loop+recorder 28 passed

pybot/tests/test_loop.py

@@ -58,9 +58,19 @@ name      alias;
    A      angle;
 @
 
+@I2C
+ name        path;
+i2c-1  /dev/i2c-1;
+@
+
+@PCA9685
+     name    I2C   address;
+pca9685-0  i2c-1   0x40;
+@
+
 @Servo
  name   max  min  offset  controller  channel;
-  s1    90     -       -           -        0;
+  s1    90     -       -   pca9685-0        0;
 @
 
 @Action
@@ -281,3 +291,98 @@ def test_loop_empty_queue_falls_back_synthetic(mock_i2c):
     # dry_run 合成帧是 numpy 数组（HWC uint8），非 int
     assert all(isinstance(f, np.ndarray) for f in frames)
     assert frames[0].shape == (240, 320, 3)   # LOOP_MT @Camera 320x240
+
+
+# ---------------- IMU 姿态回流（R2 方案一：独立 IMU token） ----------------
+
+# 在 LOOP_MT 基础上加 @MPU6050_BIND（i2c-1 已定义，相机块之前插入）
+LOOP_IMU_MT = LOOP_MT.replace(
+    "@Camera",
+    """@MPU6050_BIND
+     name    I2C   addr;
+mpu6050-0  i2c-1   0x69;
+@
+
+@Camera""")
+
+
+class ImuPredictor(MockPredictor):
+    """声明 imu_dim 的推理器桩：闭环应以 imu= 关键字调用"""
+
+    def __init__(self, *args, imu_dim=8, **kwargs):
+        super().__init__(*args, **kwargs)
+        self.imu_dim = imu_dim
+        self.imus = []         # 每步收到的 imu 向量
+
+    def predict(self, images, action_history, imu=None):
+        self.imus.append(None if imu is None else np.asarray(imu).copy())
+        return super().predict(images, action_history)
+
+
+def _freeze_imu(robot, name="mpu6050-0", **vals):
+    """停掉采样线程并注入固定姿态（避免 10ms 采样覆盖测试值）"""
+    sensor = robot.M[name].sensor
+    sensor.stop_daemon()
+    sensor.wait_daemon()
+    sensor._latest.update(**vals)
+
+
+def test_loop_imu_passed_to_predictor(mock_i2c):
+    """predictor 声明 imu_dim + 脚本含 @MPU6050_BIND → 每步 imu= 向量"""
+    robot = _make_robot(LOOP_IMU_MT, mock_i2c)
+    robot.active()
+    _freeze_imu(robot, roll=1.5, pitch=-2.0, gz=30.0)
+    pred = ImuPredictor(frame_len=3, history_len=2, action_dim=4)
+    robot.run_loop(pred, hz=1000.0, max_steps=3)
+    robot.deactive()
+
+    assert len(pred.imus) == 3
+    for imu in pred.imus:
+        assert imu is not None and imu.shape == (8,)
+        # IMU_KEYS 顺序：roll pitch ax ay az gx gy gz
+        assert imu[0] == 1.5 and imu[1] == -2.0 and imu[7] == 30.0
+
+
+def test_loop_imu_zero_without_bind(mock_i2c):
+    """predictor 声明 imu_dim 但脚本无 @MPU6050_BIND → imu 零向量输入"""
+    robot = _make_robot(LOOP_MT, mock_i2c)
+    robot.active()
+    pred = ImuPredictor(frame_len=3, history_len=2, action_dim=4)
+    robot.run_loop(pred, hz=1000.0, max_steps=2)
+    robot.deactive()
+
+    assert len(pred.imus) == 2
+    for imu in pred.imus:
+        assert imu is not None and imu.shape == (8,)
+        assert np.allclose(imu, 0.0)
+
+
+def test_loop_imu_not_passed_to_legacy_predictor(mock_i2c):
+    """未声明 imu_dim 的旧推理器：保持两参调用（向后兼容）"""
+    robot = _make_robot(LOOP_IMU_MT, mock_i2c)
+    robot.active()
+    _freeze_imu(robot, roll=9.0)
+    pred = MockPredictor(frame_len=3, history_len=2, action_dim=4)
+    robot.run_loop(pred, hz=1000.0, max_steps=2)   # 不炸即兼容
+    robot.deactive()
+    assert len(pred.calls) == 2
+
+
+def test_loop_imu_recorded(mock_i2c, tmp_path):
+    """闭环录制：含 IMU 时 imu.npy 与 actions.npy 帧对齐（T 一致）"""
+    from pybot.recorder import EpisodeRecorder
+    robot = _make_robot(LOOP_IMU_MT, mock_i2c)
+    robot.active()
+    _freeze_imu(robot, roll=3.0, ay=0.5)
+    rec = EpisodeRecorder(str(tmp_path), action_dim=18)
+    pred = MockPredictor(frame_len=3, history_len=2, action_dim=4)
+    robot.run_loop(pred, hz=1000.0, max_steps=4, recorder=rec)
+    robot.deactive()
+
+    ep = tmp_path / "episode_0000"
+    actions = np.load(ep / "actions.npy")
+    imus = np.load(ep / "imu.npy")
+    assert actions.shape == (4, 18)
+    assert imus.shape == (4, 8)          # 与 actions 帧数对齐
+    assert np.allclose(imus[:, 0], 3.0)  # roll
+    assert np.allclose(imus[:, 3], 0.5)  # ay

pybot/tests/test_recorder.py

@@ -285,6 +285,95 @@ def test_delay_not_multiple_of_10(tmp_path, mock_i2c):
     robot.deactive()
 
 
+# ---------------- IMU 姿态录制（R2） ----------------
+
+# @Camera + @MPU6050_BIND + 2 行 @Action —— 脚本驱动录制姿态
+IMU_MT = """
+@I2C
+ name        path;
+i2c-1  /dev/i2c-1;
+@
+
+@MPU6050_BIND
+     name    I2C   addr;
+mpu6050-0  i2c-1   0x69;
+@
+
+@Camera
+ name  width  height  framerate  capacity;
+ cam0    320      240        15         2;
+@
+
+@Action
+cam0.frame;
+0;
+0;
+@
+"""
+
+
+def test_imu_npy_written_with_dict(tmp_path):
+    """record 传姿态 dict → flush 产出 imu.npy（T×8），键序 roll..gz"""
+    rec = EpisodeRecorder(str(tmp_path), action_dim=18)
+    imu = {"roll": 1.0, "pitch": 2.0, "ax": 3.0, "ay": 4.0,
+           "az": 5.0, "gx": 6.0, "gy": 7.0, "gz": 8.0}
+    rec.record(None, [0.0], imu_vec=imu)
+    rec.record(None, [0.0], imu_vec=imu)
+    rec.flush()
+
+    imus = np.load(tmp_path / "episode_0000" / "imu.npy")
+    assert imus.shape == (2, 8)
+    assert list(imus[0]) == [1.0, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0]
+
+
+def test_imu_mixed_none_marks_zero(tmp_path):
+    """混合数据集：部分帧无姿态 → 该帧记零向量，仍产出 imu.npy"""
+    rec = EpisodeRecorder(str(tmp_path), action_dim=18)
+    rec.record(None, [0.0], imu_vec=None)
+    rec.record(None, [0.0], imu_vec={"roll": 9.0})
+    rec.flush()
+
+    imus = np.load(tmp_path / "episode_0000" / "imu.npy")
+    assert imus.shape == (2, 8)
+    assert np.allclose(imus[0], 0.0)
+    assert imus[1, 0] == 9.0
+
+
+def test_no_imu_no_file(tmp_path):
+    """全程无姿态（旧数据路径）→ 不产出 imu.npy，保持旧格式兼容"""
+    robot = RobotStruct(CAMERA_MT, dry_run=True)
+    robot.active()
+    rec = EpisodeRecorder(str(tmp_path), action_dim=18)
+    robot.run(recorder=rec)
+    robot.deactive()
+
+    ep_dir = tmp_path / "episode_0000"
+    assert (ep_dir / "actions.npy").exists()
+    assert not (ep_dir / "imu.npy").exists()
+
+
+def test_run_with_imu_block(tmp_path, mock_i2c):
+    """脚本含 @MPU6050_BIND 时 run() 录制产出 imu.npy 且与 actions 帧对齐"""
+    robot = RobotStruct(IMU_MT, dry_run=True)
+    robot.active()
+    # 停采样线程注入固定姿态，避免 mock 采样值干扰断言
+    sensor = robot.M["mpu6050-0"].sensor
+    sensor.stop_daemon()
+    sensor.wait_daemon()
+    sensor._latest.update(roll=-4.0, gz=12.0)
+    rec = EpisodeRecorder(str(tmp_path), action_dim=18)
+    robot.run(recorder=rec)
+    robot.deactive()
+
+    ep_dir = tmp_path / "episode_0000"
+    actions = np.load(ep_dir / "actions.npy")
+    imus = np.load(ep_dir / "imu.npy")
+    assert actions.shape == (2, 18)      # 2 行 @Action，无 Speaker 不分解
+    assert imus.shape == (2, 8)
+    assert np.allclose(imus[:, 0], -4.0)
+    assert np.allclose(imus[:, 7], 12.0)
+
+
 def test_actpred_compatibility(tmp_path, mock_i2c):
     """用 actpred 的 ActionDataset 加载录制的 episode"""
     pytest.importorskip("torch")