首先是給串口usb以權限：

sudo chmod 666 /dev/ttyUSB0

但是不能每次啟動都執行一次，所以需要給一個永久的權限指令：

sudo gedit /etc/udev/rules.d/70-ttyusb.rules

KERNEL==“ttyUSB[0-9]*”, MODE=“0666”

然后就能讓ttyUSB0-ttyUSB9默認的權限都變成了666，普通用戶也可以讀寫串口了。

或者將其添加到一個組：

ls -l /dev/ttyUSB0

whoami

當前用戶加入到dialout用戶組

sudo usermod -aG dialout username

然后重啟即可。
然后是用python解析串口的數據：

#!/usr/bin/env python3
# -*- coding: utf-8 -*-import json
import serial
import rospy
import std_msgs.msg
from car_interfaces.msg import GpsImuInterface, GpsImuAddInterface
import math
from datetime import datetime, timedelta
import time
import pyproj
import signal
import os
import sys# 獲取當前腳本文件的所在目錄
script_directory = os.path.dirname(os.path.abspath(__file__))
# 圖片文件相對于腳本文件的路徑
image_relative_path = 'lib'
# 構建圖片文件的完整路徑
icon_path = os.path.join(script_directory, image_relative_path)
# absolute_path = os.path.abspath(icon_path)# print(absolute_path)
sys.path.append(icon_path)
from base_function import *buf_pos_lat = 0
buf_pos_lon = 0
buf_vel = 0
buf_angle_heading = 0def connect_to_serial(port_name, baud_rate):try:return serial.Serial(port_name, baudrate=baud_rate, timeout=1)except serial.SerialException as e:rospy.logerr(f"Unable to connect to {port_name} with baud rate {baud_rate}: {e}")return Nonedef read_from_port(serial_port):global buf_pos_latglobal buf_pos_longlobal buf_velglobal buf_angle_headingcontent = {}# 此處放置讀取串口的邏輯 ...# start = time.time()buf_new = serial_port.readline()# print("buf new",buf_new,"serial_port",serial_port)# print(buff)# print()if ("INSPVAXA" in buf_new.decode() and "FINESTEERING" in buf_new.decode()):buf_whole_array = buf_new.decode().split(";")buf_front_arary = buf_whole_array[0].split(",")# print(buf_whole_array)buf_back_array = buf_whole_array[1].split(",")buf_pos_lon = float(buf_back_array[3])buf_pos_lat = float(buf_back_array[2])# buf_pos_alt = float(buf_back_array[4])buf_vel_east= float(buf_back_array[7])buf_vel_north= float(buf_back_array[6])buf_vel_u= float(buf_back_array[8])# 車速通過串口拿不到數據buf_vel= math.sqrt(buf_vel_east**2+buf_vel_north**2+buf_vel_u**2)buf_angle_heading = angle_2_angle(float(buf_back_array[11]))if(buf_back_array[0] == "INS_SOLUTION_GOOD"):buf_system_state = 3else:buf_system_state = 0# 搜星數量buf_gps_num_sats_used = 0buf_gps_num_sats_1 = 0buf_gps_num_sats_2 = 0if buf_front_arary[4] == "FINEBACKUPSTEERING":buf_satellite_status = 1else:buf_satellite_status = 0# 差分延時buf_gps_age = 0buf_pos_x = 0buf_pos_y = 0# 進程處理時間buf_process_time=0# 慣導通信故障buf_gps_cfault = Falsecontent["time_stamp"] = time.time()content["Lat"] = buf_pos_lat # GPS_MSG.PosLatcontent["Lon"] = buf_pos_lon # GPS_MSG.PosLoncontent["Head"] = buf_angle_heading # GPS_MSG.AngleHeadingcontent["Speed"] = buf_vel # GPS_MSG.Velcontent["UTM_x"] = from_latlon(buf_pos_lat, buf_pos_lon)[0]content["UTM_y"] = from_latlon(buf_pos_lat, buf_pos_lon)[1]# print(content)# msg.PosLon =1# # msg.PosLan =1# msg.VelE =2# # msg.posX =  388652.2938084109# # msg.posY =  4963429.720356053# msg.posX =  from_latlon(buf_pos_lat, buf_pos_lon)[0]# msg.posY =  from_latlon(buf_pos_lat, buf_pos_lon)[1]# msg.Vel = buf_vel# msg.AngleHeading = buf_angle_heading# msg.GpsNumSatsUsed = 20return contentdef main():global buf_pos_latglobal buf_pos_longlobal buf_velglobal buf_angle_headingsignal.signal(signal.SIGINT, quit)# 使用ROS參數服務器來獲取參數# serial_port_name = rospy.get_param("~serial_port", "/dev/ttyUSB0")# baud_rate = rospy.get_param("~baud_rate", 115200)serial_port_name = "/dev/ttyUSB0"baud_rate = 115200rospy.init_node("gps_imu_pub", anonymous=True)pub_location = rospy.Publisher('/ztbus/location', std_msgs.msg.String, queue_size=10)pub = rospy.Publisher("gps_imu", GpsImuInterface, queue_size = 10) msg = GpsImuInterface()while not rospy.is_shutdown():start = time.time()try:serial_port = connect_to_serial(serial_port_name, baud_rate)# print()data = read_from_port(serial_port)# print(data,"#"*8)except:print("except")continueif data :msg.PosLon =buf_pos_lonmsg.PosLat =buf_pos_latmsg.posX = from_latlon(buf_pos_lat, buf_pos_lon)[0]msg.posY = from_latlon(buf_pos_lat, buf_pos_lon)[1]msg.Vel = buf_velmsg.AngleHeading = buf_angle_headingpub_location.publish(json.dumps(data))pub.publish(msg)# rospy.loginfo("Data published to /ztbus/location topic.")prGreen("pub ok")end = time.time()interval = end -startprint('gps_interval = ', interval)# rospy.loginfo("Shutting down GPS IMU publisher node.")if __name__ == "__main__":main()

這里我的建議是將串口改成CAN口，協議也比較好確定。