#!/usr/bin/env python3
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# -*- coding: utf-8 -*-
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"""
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实时闭环控制系统
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接收 GPS/IMU 数据 → 运动控制算法 → 下发控制命令
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"""
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import serial
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import struct
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import time
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import json
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import math
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from typing import Optional, Tuple
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from gps_imu_receiver import GPSIMUReceiver, GPSData, IMUData
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from mower_controller import MowerController, wrap_angle
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EARTH_RADIUS_M = 6378137.0
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WGS84_A = 6378137.0 # 半长轴
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WGS84_F = 1 / 298.257223563
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WGS84_E2 = WGS84_F * (2 - WGS84_F)
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def _dm_to_decimal(dm_value: float) -> float:
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"""
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将度分格式 (DDMM.MMMM) 转为十进制度
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"""
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degrees = int(dm_value // 100)
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minutes = dm_value - degrees * 100
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return degrees + minutes / 60.0
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def _parse_origin_geo(origin_geo: str) -> Tuple[float, float, Optional[float]]:
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"""
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解析原点坐标字符串，支持三种格式：
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1. 标准格式: "3949.9120,N,11616.8544,E"
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2. 带前导逗号: ",3949.9120,N,11616.8544,E"
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3. GGA报文: "$GNGGA,060956.700,3949.8890014,N,11616.7555551,E,4,20,0.68,46.621,M,-6.679,M,1.0,0409*7F"
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Returns:
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(lat, lon, alt)
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如果原点字符串中不包含高度信息，则 alt 返回 None
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"""
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origin_geo = origin_geo.strip()
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# 判断是否为 GGA 报文 (以 $G 开头，包含 GGA)
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if origin_geo.startswith('$') and 'GGA' in origin_geo:
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# 解析 GGA 报文
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parts = origin_geo.split(',')
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if len(parts) < 10:
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raise ValueError(f"GGA 报文格式错误或不完整: {origin_geo}")
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# GGA 格式: $xxGGA,time,lat,NS,lon,EW,quality,numSV,HDOP,alt,altUnit...
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# parts[2]: 纬度 (ddmm.mmmmm)
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# parts[3]: N/S
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# parts[4]: 经度 (dddmm.mmmmm)
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# parts[5]: E/W
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# parts[9]: 高度
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lat_dm_str = parts[2]
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lat_dir = parts[3]
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lon_dm_str = parts[4]
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lon_dir = parts[5]
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alt_str = parts[9]
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if not (lat_dm_str and lat_dir and lon_dm_str and lon_dir and alt_str):
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raise ValueError("GGA 报文缺少必要的坐标或高度信息")
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lat_dm = float(lat_dm_str)
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lon_dm = float(lon_dm_str)
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alt = float(alt_str)
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lat = _dm_to_decimal(lat_dm)
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lon = _dm_to_decimal(lon_dm)
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if lat_dir.upper() == 'S':
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lat = -lat
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if lon_dir.upper() == 'W':
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lon = -lon
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return lat, lon, alt
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else:
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# 旧的简略格式处理
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if origin_geo.startswith(','):
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origin_geo = origin_geo[1:]
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parts = [p.strip() for p in origin_geo.split(',')]
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parts = [p for p in parts if p]
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if len(parts) != 4:
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raise ValueError("原点坐标格式应为 '纬度度分,N/S,经度度分,E/W' 或 GGA 报文")
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try:
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lat_dm = float(parts[0])
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lon_dm = float(parts[2])
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except ValueError as exc:
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raise ValueError("度分字段必须是数字") from exc
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lat = _dm_to_decimal(lat_dm)
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lon = _dm_to_decimal(lon_dm)
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lat_dir = parts[1].upper()
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lon_dir = parts[3].upper()
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if lat_dir not in ("N", "S"):
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raise ValueError("纬度方向必须为 N 或 S")
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if lon_dir not in ("E", "W"):
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raise ValueError("经度方向必须为 E 或 W")
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if lat_dir == "S":
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lat = -lat
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if lon_dir == "W":
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lon = -lon
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return lat, lon, None
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def _geo_to_ecef(lat_deg: float, lon_deg: float, alt_m: float) -> Tuple[float, float, float]:
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"""将经纬度/高度转换为ECEF坐标"""
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lat_rad = math.radians(lat_deg)
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lon_rad = math.radians(lon_deg)
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sin_lat = math.sin(lat_rad)
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cos_lat = math.cos(lat_rad)
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sin_lon = math.sin(lon_rad)
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cos_lon = math.cos(lon_rad)
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N = WGS84_A / math.sqrt(1 - WGS84_E2 * sin_lat * sin_lat)
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x = (N + alt_m) * cos_lat * cos_lon
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y = (N + alt_m) * cos_lat * sin_lon
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z = (N * (1 - WGS84_E2) + alt_m) * sin_lat
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return x, y, z
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def _ecef_to_enu(dx: float, dy: float, dz: float, lat0_rad: float, lon0_rad: float) -> Tuple[float, float, float]:
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"""将ECEF差值转换为ENU坐标"""
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sin_lat = math.sin(lat0_rad)
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cos_lat = math.cos(lat0_rad)
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sin_lon = math.sin(lon0_rad)
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cos_lon = math.cos(lon0_rad)
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east = -sin_lon * dx + cos_lon * dy
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north = -sin_lat * cos_lon * dx - sin_lat * sin_lon * dy + cos_lat * dz
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up = cos_lat * cos_lon * dx + cos_lat * sin_lon * dy + sin_lat * dz
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return east, north, up
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class ControlCommandSender:
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"""控制命令发送器 - 发送转向和油门控制信号给STM32"""
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# 协议常量
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FRAME_HEADER1 = 0xAA
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FRAME_HEADER2 = 0x55
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TYPE_CONTROL = 0x10 # 控制命令类型
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FRAME_FOOTER1 = 0x0D
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FRAME_FOOTER2 = 0x0A
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def __init__(self, serial_port: serial.Serial):
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"""
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初始化控制命令发送器
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Args:
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serial_port: 已打开的串口对象
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"""
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self.serial = serial_port
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self.send_count = 0
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def send_control_command(self, steering_pwm: int, throttle_pwm: int) -> bool:
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"""
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发送控制命令到STM32
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协议格式: AA 55 10 04 00 STEER(2) THROTTLE(2) CHECKSUM(2) 0D 0A
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Args:
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steering_pwm: 转向PWM值 (1000-2000us)
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throttle_pwm: 油门PWM值 (1000-2000us)
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Returns:
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发送成功返回True
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"""
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try:
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# 限制PWM范围
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steering_pwm = max(1000, min(2000, steering_pwm))
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throttle_pwm = max(1000, min(2000, throttle_pwm))
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# 构建数据包
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# 帧头 (2B) + 类型 (1B) + 长度 (2B) + 数据 (4B) + 校验和 (2B) + 帧尾 (2B)
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data_len = 4 # 2字节转向 + 2字节油门
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payload = struct.pack('<HH', steering_pwm, throttle_pwm)
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# 构建完整帧用于计算校验和
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checksum_data = (
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bytes([self.TYPE_CONTROL]) +
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struct.pack('<H', data_len) +
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payload
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)
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# 计算16位累加和校验
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checksum = sum(checksum_data) & 0xFFFF
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# 完整数据包
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packet = (
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bytes([self.FRAME_HEADER1, self.FRAME_HEADER2]) +
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checksum_data +
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struct.pack('<H', checksum) +
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bytes([self.FRAME_FOOTER1, self.FRAME_FOOTER2])
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)
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# 发送
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self.serial.write(packet)
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self.serial.flush()
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self.send_count += 1
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return True
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except Exception as e:
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print(f"[ERROR] 控制命令发送失败: {e}")
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return False
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def get_stats(self):
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"""获取发送统计"""
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return self.send_count
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class RealtimeController:
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"""实时控制器 - 整合GPS/IMU接收、控制算法和命令发送"""
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def __init__(self, port: str, baudrate: int = 921600,
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offset_xyz: Tuple[float, float, float] = (0.0, 0.0, 0.0),
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origin_geo: Optional[str] = None,
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origin_alt_m: Optional[float] = None):
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"""
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初始化实时控制器
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Args:
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port: 串口设备名
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baudrate: 波特率
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offset_xyz: 车辆质心相对GPS天线在东-北-天(ENU)坐标系下的偏移量(米)
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origin_geo: 坐标原点的经纬度 (度分格式字符串)，用于计算ENU坐标
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origin_alt_m: 原点的海拔高度(米)，若未提供则默认使用首次GPS高度
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"""
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self.port = port
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self.baudrate = baudrate
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self.offset_xyz = offset_xyz
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self.origin_latlon: Optional[Tuple[float, float]] = None
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self.origin_altitude: Optional[float] = origin_alt_m
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self.origin_lat_rad: Optional[float] = None
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self.origin_lon_rad: Optional[float] = None
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self.origin_ecef: Optional[Tuple[float, float, float]] = None
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if origin_geo:
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try:
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lat, lon, alt = _parse_origin_geo(origin_geo)
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self.origin_latlon = (lat, lon)
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# 如果解析出高度，且未手动指定，则优先使用解析出的高度
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if alt is not None and self.origin_altitude is None:
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self.origin_altitude = alt
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print(f"[INFO] 从原点配置中解析出高度: {self.origin_altitude:.3f} m")
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print(f"[INFO] 坐标原点设置: 纬度={self.origin_latlon[0]:.8f}°, 经度={self.origin_latlon[1]:.8f}°")
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except ValueError as exc:
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raise ValueError(f"原点坐标解析失败: {exc}") from exc
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# GPS/IMU接收器
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self.receiver = GPSIMUReceiver(port, baudrate)
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# 控制命令发送器 (共用同一个串口)
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self.cmd_sender = None
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# 运动控制器
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self.mower_ctrl = None
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# 状态变量
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self.last_gps_time = 0
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self.last_imu_time = 0
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self.control_period = 1.0 / 74.0 # 74Hz控制频率
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self.last_control_time = 0
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# 数据缓存
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self.latest_gps: Optional[GPSData] = None
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self.latest_imu: Optional[IMUData] = None
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# 统计
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self.control_count = 0
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def load_path(self, path_file: str) -> bool:
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"""
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加载路径文件并初始化控制器
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支持 .json 和 .txt (X,Y;X,Y...) 格式
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Args:
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path_file: 路径文件路径
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Returns:
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成功返回True
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"""
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try:
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with open(path_file, 'r', encoding='utf-8') as f:
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content = f.read().strip()
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path_points = []
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# 尝试解析 JSON
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try:
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if path_file.endswith('.json') or content.startswith('['):
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path_points = json.loads(content)
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except json.JSONDecodeError:
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# 假如不是JSON，尝试解析 TXT 格式
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pass
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# 如果 JSON 解析未成功或未尝试，则尝试 TXT 解析
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if not path_points:
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# TXT 格式: X,Y;X,Y;...
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points_str = content.split(';')
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for p_str in points_str:
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if not p_str.strip():
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continue
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try:
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parts = p_str.split(',')
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if len(parts) >= 2:
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x = float(parts[0])
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y = float(parts[1])
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path_points.append([x, y])
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except ValueError:
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print(f"[WARN] 忽略无效点: {p_str}")
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if not path_points:
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print("[ERROR] 未能解析出有效路径点")
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return False
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print(f"[INFO] 加载路径: {len(path_points)} 个点")
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# 使用sim_offline.py中的高精度参数
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params = {
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# 核心控制增益
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'k_heading': 2.0,
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'k_xte': 0.8,
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'k_heading_d': 0.1,
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'k_heading_i': 0.015,
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'k_xte_i': 0.02,
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# 速度控制
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'base_speed': 0.8,
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'max_forward_mps': 1.2,
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'min_follow_speed': 0.40,
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'max_reverse_mps': 0.25,
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'max_yawrate': math.pi/2.5,
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# 前视距离
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'lookahead_min': 0.35,
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'lookahead_max': 1.2,
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'lookahead_time': 2.0,
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# 误差容忍度
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'max_xte': 1.5,
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'goal_tolerance': 0.1,
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'large_err_threshold': 0.5,
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# 滤波参数
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'yawrate_alpha': 0.85,
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# 速度缩放增益
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'curv_gain_scale': 2.0,
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'heading_err_gain_scale': 1.5,
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'xte_gain_scale': 1.0,
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# 终点减速区域
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'slow_zone': 1.5,
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'final_approach_dist': 0.8,
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}
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self.mower_ctrl = MowerController(path_points, params=params)
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print("[INFO] 运动控制器初始化完成")
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return True
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except Exception as e:
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print(f"[ERROR] 加载路径失败: {e}")
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return False
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def connect(self) -> bool:
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"""连接串口"""
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if not self.receiver.connect():
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return False
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# 创建控制命令发送器 (共用串口对象)
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self.cmd_sender = ControlCommandSender(self.receiver.serial)
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print("[INFO] 控制命令发送器就绪")
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return True
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def disconnect(self):
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"""断开连接"""
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self.receiver.disconnect()
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def _ensure_origin_reference(self, fallback_altitude: float):
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"""确保已根据原点经纬度初始化ECEF基准"""
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if not self.origin_latlon or self.origin_ecef:
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return
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lat0, lon0 = self.origin_latlon
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if self.origin_altitude is None:
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self.origin_altitude = fallback_altitude
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print(f"[INFO] 未指定原点高度，使用首个GPS高度 {self.origin_altitude:.3f} m")
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self.origin_lat_rad = math.radians(lat0)
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self.origin_lon_rad = math.radians(lon0)
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self.origin_ecef = _geo_to_ecef(lat0, lon0, self.origin_altitude)
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print(f"[INFO] 原点ECEF参考初始化完成 (Alt={self.origin_altitude:.3f} m)")
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def _convert_gps_to_local(self, gps: GPSData) -> tuple:
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"""
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将GPS数据转换为本地坐标 (简化版，实际需要根据起点转换)
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Returns:
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(x, y, z, heading_rad, vx, vy)
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"""
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# TODO: 实际应用中需要将经纬度转换为相对起点的XY坐标
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# 这里简化处理，假设GPS已提供相对坐标或使用UTM转换
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# 航向角转换为弧度 (GPS输出0-360°，北为0°顺时针)
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# 需要转换为数学坐标系 (东为0°逆时针)
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heading_rad = math.radians(90 - gps.heading_angle)
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heading_rad = wrap_angle(heading_rad)
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# 速度分量 (GPS提供东北天坐标系)
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vx = gps.east_velocity # 东向速度 = X轴速度
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vy = gps.north_velocity # 北向速度 = Y轴速度
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# 位置转换为ENU坐标
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lat = gps.latitude
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lon = gps.longitude
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x = 0.0
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y = 0.0
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z = 0.0
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if self.origin_latlon:
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self._ensure_origin_reference(gps.altitude)
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if self.origin_latlon and self.origin_ecef and self.origin_lat_rad is not None and self.origin_lon_rad is not None:
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current_ecef = _geo_to_ecef(lat, lon, gps.altitude)
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dx = current_ecef[0] - self.origin_ecef[0]
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dy = current_ecef[1] - self.origin_ecef[1]
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dz = current_ecef[2] - self.origin_ecef[2]
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east, north, up = _ecef_to_enu(dx, dy, dz, self.origin_lat_rad, self.origin_lon_rad)
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x = east
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y = north
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z = up
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else:
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x = lon * 111320.0 * math.cos(math.radians(lat)) # 近似米
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y = lat * 110540.0 # 近似米
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z = gps.altitude # 粗略使用GPS高度
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# GPS天线 → 车辆中心的平移修正 (ENU坐标系)
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dx, dy, dz_offset = self.offset_xyz
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x += dx
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y += dy
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z += dz_offset
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return (x, y, z, heading_rad, vx, vy)
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def _control_to_pwm(self, forward: int, turn: int) -> tuple:
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"""
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将控制信号转换为PWM值
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Args:
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forward: 前进信号 (-100 到 100)
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turn: 转向信号 (-100 到 100, 负为右转, 正为左转)
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Returns:
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(steering_pwm, throttle_pwm) 单位us
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"""
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# 油门: -100~100 映射到 1000~2000us, 中位1500us
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throttle_pwm = int(1500 + forward * 5.0)
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# 转向: -100~100 映射到 1000~2000us, 中位1500us
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# 注意: 正值左转(1000), 负值右转(2000)
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steering_pwm = int(1500 - turn * 5.0)
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return (steering_pwm, throttle_pwm)
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def run(self):
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"""运行实时控制循环"""
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if not self.mower_ctrl:
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print("[ERROR] 请先加载路径文件")
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return
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print("[INFO] 开始实时控制... (按 Ctrl+C 停止)")
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print("[INFO] 等待GPS数据...")
|
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try:
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start_time = time.time()
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last_stats_time = start_time
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# 等待第一个有效的GPS数据
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gps_ready = False
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while not gps_ready:
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gps_data, imu_data = self.receiver.receive_packet()
|
|
if gps_data:
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if gps_data.position_quality > 0 and gps_data.satellite_count >= 4:
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self.latest_gps = gps_data
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gps_ready = True
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print(f"[INFO] GPS就绪: 质量={gps_data.position_quality}, 卫星={gps_data.satellite_count}")
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else:
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print(f"[WARN] GPS质量不足: 质量={gps_data.position_quality}, 卫星={gps_data.satellite_count}")
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if imu_data:
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self.latest_imu = imu_data
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print("[INFO] 开始控制循环")
|
|
while True:
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current_time = time.time()
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# 接收数据 (非阻塞式，快速轮询)
|
gps_data, imu_data = self.receiver.receive_packet()
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if gps_data:
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self.latest_gps = gps_data
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self.last_gps_time = current_time
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if imu_data:
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self.latest_imu = imu_data
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self.last_imu_time = current_time
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# 控制周期检查 (74Hz)
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if current_time - self.last_control_time >= self.control_period:
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if self.latest_gps:
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# 转换GPS数据到本地坐标
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x, y, z, heading, vx, vy = self._convert_gps_to_local(self.latest_gps)
|
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# 更新控制器状态 (只用x,y)
|
self.mower_ctrl.update_gps((x, y), heading, (vx, vy), current_time)
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if self.latest_imu:
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accel = (self.latest_imu.accel_x, self.latest_imu.accel_y, self.latest_imu.accel_z)
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gyro = (self.latest_imu.gyro_x, self.latest_imu.gyro_y, self.latest_imu.gyro_z)
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self.mower_ctrl.update_imu(accel, gyro, current_time)
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|
# 计算控制信号
|
control_output = self.mower_ctrl.compute_control(current_time)
|
forward_signal = control_output['forward'] # -100~100
|
turn_signal = control_output['turn'] # -100~100
|
|
# 转换为PWM并发送
|
steering_pwm, throttle_pwm = self._control_to_pwm(forward_signal, turn_signal)
|
self.cmd_sender.send_control_command(steering_pwm, throttle_pwm)
|
|
self.control_count += 1
|
self.last_control_time = current_time
|
|
# 打印控制信息 (降低频率)
|
if self.control_count % 74 == 0: # 每秒打印一次
|
status = control_output['info'].get('status', 'running')
|
xte = control_output['info'].get('xte', 0)
|
# 数学角度转地理角度：heading_err_deg
|
# 注意 control_output['info']['heading_err'] 是弧度
|
heading_err_deg = math.degrees(control_output['info'].get('heading_err', 0))
|
|
# 获取最新的姿态角 (优先使用 GPS 数据，IMU 作为辅助或高频补充，这里直接用 GPS 结构体中的角度)
|
# GPSData 中: heading_angle(0-360), pitch_angle, roll_angle
|
# 都是角度制
|
gps_heading = self.latest_gps.heading_angle
|
gps_pitch = self.latest_gps.pitch_angle
|
gps_roll = self.latest_gps.roll_angle
|
|
print(f"[LOG] POS_ENU: {x:.3f}, {y:.3f}, {z:.3f} | "
|
f"ATT(H/P/R): {gps_heading:.2f}°, {gps_pitch:.2f}°, {gps_roll:.2f}° | "
|
f"CTRL: S={status}, F={forward_signal}, T={turn_signal}, Err={xte:.2f}m")
|
|
# 检查是否完成
|
if control_output['info'].get('status') == 'finished':
|
print("[INFO] 路径跟踪完成!")
|
break
|
|
# 统计信息 (每10秒)
|
# if current_time - last_stats_time > 10.0:
|
# print(f"\n========== 运行统计 ==========")
|
# print(f"运行时间: {current_time - start_time:.1f}s")
|
# print(f"控制次数: {self.control_count}")
|
# print(f"GPS数据包: {self.receiver.gps_count}")
|
# print(f"IMU数据包: {self.receiver.imu_count}")
|
# print(f"命令发送: {self.cmd_sender.get_stats()}")
|
# print(f"错误计数: {self.receiver.error_count}")
|
|
# if self.latest_gps:
|
# print(f"GPS状态: 质量={self.latest_gps.position_quality}, "
|
# f"卫星={self.latest_gps.satellite_count}, "
|
# f"航向={self.latest_gps.heading_angle:.1f}°")
|
|
# print(f"==============================\n")
|
# last_stats_time = current_time
|
|
except KeyboardInterrupt:
|
print("\n[INFO] 用户中断")
|
|
finally:
|
# 发送停止命令 (中位值)
|
print("[INFO] 发送停止命令...")
|
for _ in range(5):
|
self.cmd_sender.send_control_command(1500, 1500)
|
time.sleep(0.02)
|
|
# 打印最终统计
|
print("\n========== 最终统计 ==========")
|
print(f"总控制次数: {self.control_count}")
|
print(f"GPS数据包: {self.receiver.gps_count}")
|
print(f"IMU数据包: {self.receiver.imu_count}")
|
print(f"命令发送: {self.cmd_sender.get_stats()}")
|
print(f"错误计数: {self.receiver.error_count}")
|
print("==============================\n")
|
|
|
def main():
|
"""主函数"""
|
# 配置
|
PORT = "COM17" # 根据实际情况修改
|
BAUDRATE = 921600
|
PATH_FILE = "gecaolujing2.txt" # 路径文件
|
OFFSET_XYZ = (0.0, 0.0, 0.0) # 车辆中心相对GPS天线的ENU偏移(米): (东, 北, 天)
|
|
# 原点经纬度 (支持 GGA 报文或简略格式)
|
# 示例GGA: "$GNGGA,060956.700,3949.8890014,N,11616.7555551,E,4,20,0.68,46.621,M,-6.679,M,1.0,0409*7F"
|
ORIGIN_GEO = "$GNGGA,060956.700,3949.8890014,N,11616.7555551,E,4,20,0.68,46.621,M,-6.679,M,1.0,0409*7F"
|
|
ORIGIN_ALT = None # 原点海拔(米)，可选。若GGA报文中包含海拔，会自动使用报文中的海拔。
|
|
# 创建控制器
|
controller = RealtimeController(
|
PORT,
|
BAUDRATE,
|
offset_xyz=OFFSET_XYZ,
|
origin_geo=ORIGIN_GEO,
|
origin_alt_m=ORIGIN_ALT
|
)
|
|
# 加载路径
|
if not controller.load_path(PATH_FILE):
|
print("[ERROR] 路径加载失败，退出")
|
return
|
|
# 连接串口
|
if not controller.connect():
|
print("[ERROR] 串口连接失败，退出")
|
return
|
|
# 运行控制循环
|
try:
|
controller.run()
|
finally:
|
controller.disconnect()
|
|
|
if __name__ == "__main__":
|
main()
|
