"""bridge.py —— 吊舱 ↔ PX4 桥接主循环（asyncio 胶水层）。 闭环（每控制周期，guidance.frequency_hz）： ① poll 吊舱串口 → 缓存最新 表4 目标经纬度 / 表2-2 遥测（带单调时间戳） ② 按 link.attitude_downlink_hz 节流，读 PX4 遥测 → 打包 表3 载机姿态下发吊舱 （吊舱据此解算目标经纬度，文档要求 1~60Hz） ③ 目标门控：表2-2 状态字节1 bit2=锁定 且遥测在 link.telemetry_timeout_ms 内， 表4 坐标才视为有效（规格：表4 周期发送，搜索状态下坐标无意义；激光无效时 吊舱不解算、表4 自然中断，由 guidance.target_stale_ms 兜底） ④ 自身状态 + 最新目标 → GuidanceInput → GuidanceLaw.update → ControlOutput ⑤ 按模式分发：VELOCITY_HEADING → offboard 速度；BRAKE_HOVER → 零速刹车 （引导律对一切不安全情形输出 BRAKE_HOVER，故 offboard 始终有心跳，无失联悬停） run() 主循环带异常护栏：单周期异常（如串口拔线）按节流节奏告警并补发零速刹车 保 offboard 心跳，任务不终止。 时钟一致性：Px4Gateway 与 PodBridge 必须共用同一单调毫秒时钟（OwnState.time_ms 与 step(now_ms) 同源），否则 position/target 超龄判定失效。connect() 工厂已统一。 """ import asyncio import logging import math import time from datetime import datetime, timezone from typing import Optional from visual_track_control.staleness_checker import is_stale from visual_track_control.types import ControlMode from .config import BridgeConfig from .guidance import GuidanceInput, GuidanceLaw from .pod_serial import PodLink, PodSerial from .protocol import (CarrierAttitude, ControlCommand, TargetGeo, Telemetry, encode_attitude, encode_control) from .px4_gateway import Px4Gateway logger = logging.getLogger(__name__) def _monotonic_ms() -> int: return int(time.monotonic() * 1000) class PodBridge: """px4：Px4Gateway（或等价 mock）；pod：PodLink（PodSerial 或内存 FakePod）。""" def __init__(self, cfg: BridgeConfig, px4: Px4Gateway, pod: PodLink, now_ms_fn=_monotonic_ms) -> None: self._cfg = cfg self._px4 = px4 self._pod = pod self._now_ms = now_ms_fn self._guidance = GuidanceLaw(cfg.guidance) self._attitude_period_ms = max( 1, int(round(1000.0 / cfg.link.attitude_downlink_hz))) self._last_attitude_ms: Optional[int] = None self._latest_target = None # (TargetGeo, time_ms) self._latest_telemetry = None # (Telemetry, time_ms) self._step_failures = 0 # run() 连续异常计数（告警节流用） # --- 生命周期 ----------------------------------------------------------- async def start(self) -> bool: """启动 PX4 遥测订阅与 offboard；offboard 失败返回 False（不应继续闭环）。""" await self._px4.start_telemetry() if not await self._px4.start_offboard(): logger.error("[Bridge] offboard 启动失败，桥接未运行") return False logger.info("[Bridge] 启动：引导 %.1fHz，姿态下发 %.1fHz", self._cfg.guidance.frequency_hz, self._cfg.link.attitude_downlink_hz) return True async def stop(self) -> None: """安全停机：先零速刹车，再停 offboard / 遥测 / 串口。""" try: await self._px4.send_brake_hover(self._now_ms()) finally: await self._px4.stop_offboard() await self._px4.stop_telemetry() self._pod.close() self._guidance.reset() logger.info("[Bridge] 已停止") # --- 主循环 ------------------------------------------------------------- async def run(self, stop_event: asyncio.Event) -> None: """按引导频率循环 step()，直到 stop_event 置位。 异常护栏：单周期抛错（典型：吊舱串口拔线 SerialException/OSError）不终止 任务，按「第 1 次 + 每满 100 次」节奏告警（对齐 WarnThrottle 语义），并补发 零速刹车保住 offboard 心跳——否则 PX4 数秒内触发 offboard 失联保护。 CancelledError 继承 BaseException，不在此拦截。 """ period_s = 1.0 / self._cfg.guidance.frequency_hz while not stop_event.is_set(): try: await self.step(self._now_ms()) self._step_failures = 0 except Exception as exc: self._step_failures += 1 if self._step_failures == 1 or self._step_failures % 100 == 0: logger.warning("[Bridge] 控制周期异常(第 %d 次): %s", self._step_failures, exc) try: await self._px4.send_brake_hover(self._now_ms()) except Exception: pass # 补发失败不掩盖原异常，下周期重试 await asyncio.sleep(period_s) async def step(self, now_ms: int): """单控制周期（显式传入时钟，便于确定性单测）。返回 ControlOutput。""" self._ingest_pod_frames(now_ms) own = self._px4.own_state() self._downlink_attitude(own, now_ms) out = self._guidance.update(self._build_guidance_input(own, now_ms), now_ms) await self._dispatch(out, now_ms) return out # --- 吊舱侧 ------------------------------------------------------------- def _ingest_pod_frames(self, now_ms: int) -> None: for frame in self._pod.poll(): if isinstance(frame, TargetGeo): self._latest_target = (frame, now_ms) elif isinstance(frame, Telemetry): self._latest_telemetry = (frame, now_ms) def _downlink_attitude(self, own, now_ms: int) -> None: if (self._last_attitude_ms is not None and now_ms - self._last_attitude_ms < self._attitude_period_ms): return self._pod.send(encode_attitude(self._build_attitude(own))) self._last_attitude_ms = now_ms def _build_attitude(self, own) -> CarrierAttitude: t = datetime.now(timezone.utc) return CarrierAttitude( roll_deg=math.degrees(own.roll_rad), pitch_deg=math.degrees(own.pitch_rad), yaw_deg=math.degrees(own.yaw_rad), latitude_deg=own.latitude_deg, longitude_deg=own.longitude_deg, abs_alt_m=own.absolute_altitude_m, rel_alt_m=own.relative_altitude_m, year=t.year, month=t.month, day=t.day, hour=t.hour, minute=t.minute, second=t.second, centisecond=t.microsecond // 10000, airspeed_mps=0.0, # 无空速管，置 0（文档允许） ground_speed_mps=own.ground_speed_mps, ) def send_control(self, cmd: ControlCommand) -> None: """触发式下发 表2-1 控制指令（如开目标识别 / 框选跟踪）。""" self._pod.send(encode_control(cmd)) # --- 飞控侧 ------------------------------------------------------------- def _build_guidance_input(self, own, now_ms: int) -> GuidanceInput: tgt = self._latest_target locked = self._pod_locked(now_ms) return GuidanceInput( own_lat_deg=own.latitude_deg, own_lon_deg=own.longitude_deg, own_yaw_deg=math.degrees(own.yaw_rad), own_position_valid=own.position_valid, own_position_time_ms=own.position_time_ms, # position 流专用时间戳 target_lat_deg=tgt[0].latitude_deg if tgt else 0.0, target_lon_deg=tgt[0].longitude_deg if tgt else 0.0, target_valid=tgt is not None and locked, # 未锁定=目标无效 target_time_ms=tgt[1] if tgt else 0, ) def _pod_locked(self, now_ms: int) -> bool: """吊舱锁定门控：表2-2 遥测在 link.telemetry_timeout_ms 内且状态字节1 bit2=锁定 才算锁定。从未收到遥测 / 遥测超龄 / 搜索状态一律视为未锁定 （宁可刹车，不朝搜索状态下的无意义坐标飞）。""" tel = self._latest_telemetry if tel is None: return False frame, t_ms = tel if is_stale(t_ms, now_ms, self._cfg.link.telemetry_timeout_ms): return False return frame.is_target_locked async def _dispatch(self, out, now_ms: int) -> None: if out.mode is ControlMode.VELOCITY_HEADING and out.valid: await self._px4.send_velocity_heading(out, now_ms) elif out.mode is ControlMode.BRAKE_HOVER and out.valid: await self._px4.send_brake_hover(now_ms) # --- 诊断访问 ----------------------------------------------------------- @property def latest_target(self): return self._latest_target @property def latest_telemetry(self): return self._latest_telemetry # --- 实机工厂 ----------------------------------------------------------- @classmethod async def connect(cls, cfg: BridgeConfig) -> "PodBridge": """按配置连接 PX4(MAVSDK) 与吊舱(串口)，共用单一单调时钟。""" px4 = await Px4Gateway.connect(cfg.px4.connection_string, now_ms_fn=_monotonic_ms) pod = PodSerial(cfg.pod_serial.port, cfg.pod_serial.baudrate) return cls(cfg, px4, pod, now_ms_fn=_monotonic_ms)