ESP8266和ROS收发消息读取模拟量控制LED亮度ESP8266和ROS调试一些问题汇总

如果需要ESP8266和ROS通信先阅读如下博客：

• ESP8266和ROS调试一些问题汇总

• https://zhangrelay.blog.csdn.net/article/details/108762844

这里测试环境melodic和noetic都可行。

源代码如下：

  

   

    

     

    
    

     

      #if (ARDUINO >= 100)
     
    
   

    

     

    
    

     
 #include <Arduino.h>
     
    
   

    

     

    
    

     

      #else
     
    
   

    

     

    
    

     
 #include <WProgram.h>
     
    
   

    

     

    
    

     

      #endif
     
    
   

    

     

    
    

     

      #include <ESP8266WiFi.h>
     
    
   

    

     

    
    

     

      #include <ros.h>
     
    
   

    

     

    
    

     

      #include <std_msgs/String.h>
     
    
   

    

     

    
    

     

      #include <std_msgs/Int16.h>
     
    
   

    

     

    
    

     

      #include <std_msgs/Float64.h>
     
    
   

    

     

    
    

     

      #include <Servo.h>
     
    
   

    

     

    
    

     

      #include <rosserial_arduino/Adc.h>
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      //
     
    
   

    

     

    
    

     

      // WiFi Definitions //
     
    
   

    

     

    
    

     

      //
     
    
   

    

     

    
    

     

      const char* ssid = "HUAWEI_WiFi";
     
    
   

    

     

    
    

     

      const char* password = "cslgcslg";
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      IPAddress server(192, 168, 3, 153); // ip of your ROS server
     
    
   

    

     

    
    

     

      IPAddress ip_address;
     
    
   

    

     

    
    

     

      int status = WL_IDLE_STATUS;
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      WiFiClient client;
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      class WiFiHardware {
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
  public:
     
    
   

    

     

    
    

     

        WiFiHardware() {};
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
  void init() {
     
    
   

    

     

    
    

     
 // do your initialization here. this probably includes TCP server/client setup
     
    
   

    

     

    
    

     

       client.connect(server, 11411);
     
    
   

    

     

    
    

     

        }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
  // read a byte from the serial port. -1 = failure
     
    
   

    

     

    
    

     
  int read() {
     
    
   

    

     

    
    

     
 // implement this method so that it reads a byte from the TCP connection and returns it
     
    
   

    

     

    
    

     
 // you may return -1 is there is an error; for example if the TCP connection is not open
     
    
   

    

     

    
    

     
 return client.read(); //will return -1 when it will works
     
    
   

    

     

    
    

     

        }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
  // write data to the connection to ROS
     
    
   

    

     

    
    

     
  void write(uint8_t* data, int length) {
     
    
   

    

     

    
    

     
 // implement this so that it takes the arguments and writes or prints them to the TCP connection
     
    
   

    

     

    
    

     
 for(int i=0; i<length; i++)
     
    
   

    

     

    
    

     

       client.write(data[i]);
     
    
   

    

     

    
    

     

        }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
  // returns milliseconds since start of program
     
    
   

    

     

    
    

     
  unsigned long time() {
     
    
   

    

     

    
    

     
 return millis(); // easy; did this one for you
     
    
   

    

     

    
    

     

        }
     
    
   

    

     

    
    

     

      };
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      Servo s;
     
    
   

    

     

    
    

     

      int i;
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      void chatterCallback(const std_msgs::String& msg) {
     
    
   

    

     

    
    

     

        i = atoi(msg.data);
     
    
   

    

     

    
    

     

        s.write(i);
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      std_msgs::String str_msg;
     
    
   

    

     

    
    

     

      rosserial_arduino::Adc adc_msg;
     
    
   

    

     

    
    

     

      ros::Publisher chatter("chatter", &str_msg);
     
    
   

    

     

    
    

     

      ros::Publisher p("adc", &adc_msg);
     
    
   

    

     

    
    

     

      ros::Subscriber<std_msgs::String> sub("message", &chatterCallback);
     
    
   

    

     

    
    

     

      ros::NodeHandle_<WiFiHardware> nh;
     
    
   

    

     

    
    

     

      char hello[20] = "ESP8266 wifi alive!";
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      void setupWiFi()
     
    
   

    

     

    
    

     

      {
     
    
   

    

     

    
    

     

        WiFi.begin(ssid, password);
     
    
   

    

     

    
    

     

        Serial.print("\nConnecting to "); Serial.println(ssid);
     
    
   

    

     

    
    

     
  uint8_t i = 0;
     
    
   

    

     

    
    

     
  while (WiFi.status() != WL_CONNECTED && i++ < 20) delay(500);
     
    
   

    

     

    
    

     
  if(i == 21){
     
    
   

    

     

    
    

     

       Serial.print("Could not connect to"); Serial.println(ssid);
     
    
   

    

     

    
    

     
 while(1) delay(500);
     
    
   

    

     

    
    

     

        }
     
    
   

    

     

    
    

     

        Serial.print("Ready! Use ");
     
    
   

    

     

    
    

     

        Serial.print(WiFi.localIP());
     
    
   

    

     

    
    

     

        Serial.println(" to access client");
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      int averageAnalog(int pin){
     
    
   

    

     

    
    

     
  int v=0;
     
    
   

    

     

    
    

     
  for(int i=0; i<2; i++) v+= analogRead(pin);
     
    
   

    

     

    
    

     
  return v/2;
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      void setup() {
     
    
   

    

     

    
    

     

        Serial.begin(115200);
     
    
   

    

     

    
    

     

        setupWiFi();
     
    
   

    

     

    
    

     

        delay(2000);
     
    
   

    

     

    
    

     

        s.attach(13);  // PWM pin
     
    
   

    

     

    
    

     

        nh.initNode();
     
    
   

    

     

    
    

     

        nh.advertise(chatter);
     
    
   

    

     

    
    

     

        nh.subscribe(sub);
     
    
   

    

     

    
    

     

        nh.advertise(p);
     
    
   

    

     

    
    

     

      }
     
    
   

    

     

    
    

     
 
     
    
   

    

     

    
    

     

      void loop() {
     
    
   

    

     

    
    

     

        str_msg.data = hello;
     
    
   

    

     

    
    

     

        chatter.publish( &str_msg );
     
    
   

    

     

    
    

     

        adc_msg.adc0 = averageAnalog( 0 );
     
    
   

    

     

    
    

     

        p.publish( &adc_msg );
     
    
   

    

     

    
    

     

        nh.spinOnce();
     
    
   

    

     

    
    

     

        delay( 10 );
     
    
   

    

     

    
    

     

      }
     
    
  
 

简单解释一下，发布节点chatter，adc，订阅节点message。

1. message提取数值作为PWM波送到13脚控制LED亮度（占空比）；
2. adc采集模拟量绘制曲线；
3. chatter只用作发布消息，告知主机连接成功。

使用如下命令启动wemos D1和ROS：

• roscore
• rosrun rosserial_python serial_node.py tcp
• rostopic pub /message std_msgs/String "data: '10'"
• rostopic echo /adc
• rostopic echo /chatter

过程如下：

roscore

rosrun rosserial_python serial_node.py tcp

主题列表：

rostopic pub /message std_msgs/String "data: '10'"

使用rqt_graph查看所有节点状态：

使用rosbag记录ADC数据并使用plot查看曲线：

关闭所有节点，只留下roscore，使用rosbag play查看记录数据：

 所有Arduino，stm32等单片机都可以借助ROS实现物联网硬件功能。

-Fin-

文章来源: zhangrelay.blog.csdn.net，作者：zhangrelay，版权归原作者所有，如需转载，请联系作者。

原文链接：zhangrelay.blog.csdn.net/article/details/108856947