card Infrared avoid

//#include <Servo.h>
int Left_motor_go = 8;    //左电机前进(IN1)
int Left_motor_back = 9;  //左电机后退(IN2)

int Right_motor_go = 10;    // 右电机前进(IN3)
int Right_motor_back = 11;  // 右电机后退(IN4)

int key = A2;   //定义按键 数字A2 接口
int beep = A3;  //定义蜂鸣器 数字A3 接口

int LED = 7;  //定义LED 数字7 接口

const int SensorRight_2 = 5;  //中间红外避障传感器(P3.4 OUT3)

int SR_2;  //右红外传感器状态

void setup() {
  //初始化电机驱动IO为输出方式
  pinMode(Left_motor_go, OUTPUT);     // PIN 8 ( 无 PWM)
  pinMode(Left_motor_back, OUTPUT);   // PIN 9 (PWM)
  pinMode(Right_motor_go, OUTPUT);    // PIN 10 (PWM)
  pinMode(Right_motor_back, OUTPUT);  // PIN 11 (PWM)
  pinMode(key, INPUT);                //定义按键接口为输入接口
  pinMode(beep, OUTPUT);              //定义蜂鸣器为输出接口
  pinMode(LED, OUTPUT);               //定义LED为输出接口

  pinMode(SensorRight_2, INPUT);  //定义中间避障传感器为输入
}

void run()  // 前进
{
  digitalWrite(Right_motor_go, HIGH);  // 右电机前进
  digitalWrite(Right_motor_back, LOW);
  analogWrite(Right_motor_go, 160);  //PWM比例0~255调速，左右轮差异略增减
  analogWrite(Right_motor_back, 0);
  digitalWrite(Left_motor_go, LOW);  // 左电机前进
  digitalWrite(Left_motor_back, HIGH);
  analogWrite(Left_motor_go, 0);  //PWM比例0~255调速，左右轮差异略增减
  analogWrite(Left_motor_back, 160);
  //delay(time * 100);   //执行时间，可以调整
}

void brake(int time)  //刹车，停车
{
  digitalWrite(Right_motor_go, LOW);
  digitalWrite(Right_motor_back, LOW);
  digitalWrite(Left_motor_go, LOW);
  digitalWrite(Left_motor_back, LOW);
  delay(time * 100);  //执行时间，可以调整
}

//void left(int time)         //左转(左轮不动，右轮前进)
void left(int time)  //左转(左轮不动，右轮前进)
{
  digitalWrite(Right_motor_go, HIGH);  // 右电机前进
  digitalWrite(Right_motor_back, LOW);
  analogWrite(Right_motor_go, 200);
  analogWrite(Right_motor_back, 0);  //PWM比例0~255调速
  digitalWrite(Left_motor_go, LOW);  //左轮后退
  digitalWrite(Left_motor_back, LOW);
  analogWrite(Left_motor_go, 0);
  analogWrite(Left_motor_back, 0);  //PWM比例0~255调速
  delay(time * 100);                //执行时间，可以调整
}

void spin_left(int time)  //左转(左轮后退，右轮前进)
{
  digitalWrite(Right_motor_go, HIGH);  // 右电机前进
  digitalWrite(Right_motor_back, LOW);
  analogWrite(Right_motor_go, 200);
  analogWrite(Right_motor_back, 0);   //PWM比例0~255调速
  digitalWrite(Left_motor_go, HIGH);  //左轮后退
  digitalWrite(Left_motor_back, LOW);
  analogWrite(Left_motor_go, 200);
  analogWrite(Left_motor_back, 0);  //PWM比例0~255调速
  delay(time * 100);                //执行时间，可以调整
}

//void right(int time)
void right()  //右转(右轮不动，左轮前进)
{
  digitalWrite(Right_motor_go, LOW);  //右电机后退
  digitalWrite(Right_motor_back, LOW);
  analogWrite(Right_motor_go, 0);
  analogWrite(Right_motor_back, 0);  //PWM比例0~255调速
  digitalWrite(Left_motor_go, LOW);  //左电机前进
  digitalWrite(Left_motor_back, HIGH);
  analogWrite(Left_motor_go, 0);
  analogWrite(Left_motor_back, 200);  //PWM比例0~255调速
  //delay(time * 100);	//执行时间，可以调整
}

void spin_right(int time)  //右转(右轮后退，左轮前进)
{
  digitalWrite(Right_motor_go, LOW);  //右电机后退
  digitalWrite(Right_motor_back, HIGH);
  analogWrite(Right_motor_go, 0);
  analogWrite(Right_motor_back, 200);  //PWM比例0~255调速
  digitalWrite(Left_motor_go, LOW);    //左电机前进
  digitalWrite(Left_motor_back, HIGH);
  analogWrite(Left_motor_go, 0);
  analogWrite(Left_motor_back, 200);  //PWM比例0~255调速
  delay(time * 100);                  //执行时间，可以调整
}

void back(int time)  //后退
{
  digitalWrite(Right_motor_go, LOW);  //右轮后退
  digitalWrite(Right_motor_back, HIGH);
  analogWrite(Right_motor_go, 0);
  analogWrite(Right_motor_back, 150);  //PWM比例0~255调速
  digitalWrite(Left_motor_go, HIGH);   //左轮后退
  digitalWrite(Left_motor_back, LOW);
  analogWrite(Left_motor_go, 150);
  analogWrite(Left_motor_back, 0);  //PWM比例0~255调速
  delay(time * 100);                //执行时间，可以调整
}

void keysacn()  //按键扫描
{
  int val;
  val = digitalRead(key);    //读取数字7 口电平值赋给val
  while (!digitalRead(key))  //当按键没被按下时，一直循环
  {
    val = digitalRead(key);  //此句可省略，可让循环跑空
  }
  while (digitalRead(key))  //当按键被按下时
  {
    delay(10);               //延时10ms
    val = digitalRead(key);  //读取数字7 口电平值赋给val
    if (val == HIGH)         //第二次判断按键是否被按下
    {
      digitalWrite(beep, HIGH);   //蜂鸣器响
      while (!digitalRead(key))   //判断按键是否被松开
        digitalWrite(beep, LOW);  //蜂鸣器停止
    } else
      digitalWrite(beep, LOW);  //蜂鸣器停止
  }
}

void loop() {
  keysacn();  //调用按键扫描函数
  while (1) {
    //有信号为LOW  没有信号为HIGH  有障碍物输出0  没有障碍物输出1
    SR_2 = digitalRead(SensorRight_2);
    if (SR_2 == HIGH)  //前面没有障碍物
    {
      run();                    //调用前进函数
      digitalWrite(beep, LOW);  //蜂鸣器不响
      digitalWrite(LED, LOW);   //LED不亮
    } else if (SR_2 == LOW)     // 前面探测到有障碍物，有信号返回
    {
      digitalWrite(beep, HIGH);  //蜂鸣器响
      digitalWrite(LED, HIGH);   //LED亮
      brake(3);                  //停止300MS
      back(4);                   //后退400MS
      left(5);                   //调用左转函数  延时500ms
    }
  }
}