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我正在使用带有反射传感器的 zumo 机器人，用于跟随黑线。我想使用 arduino 让 zumo 机器人在距离障碍物一定距离后停止。

我有一个连接到机器人的超声波传感器（HC-SR04）。

这两个任务都是独立工作的，但是一旦我将代码合并在一起（所以它会沿着线以及在使用超声波传感器检测到物体时停止），它不能正常工作..（zumo bot 不再跟随线)

我认为这与 pulsein() 函数阻止任何其他任务有关，但不确定。

我的代码如下。有人可以帮忙吗？

#include <ZumoShield.h>

ZumoBuzzer buzzer;
ZumoReflectanceSensorArray reflectanceSensors;
ZumoMotors motors;
Pushbutton button(ZUMO_BUTTON);
int lastError = 0;

// This is the maximum speed the motors will be allowed to turn.
// (400 lets the motors go at top speed; decrease to impose a speed limit)
const int MAX_SPEED = 400;
#define echoPin A4 
#define trigPin A5

// defines variables
long duration; // variable for the duration of sound wave travel
int distance; // variable for the distance measurement

void setup()
{
  reflectanceSensors.init();

  pinMode(trigPin, OUTPUT); // Sets the trigPin as an OUTPUT
  pinMode(echoPin, INPUT); // Sets the echoPin as an INPUT

  // Initialize the reflectance sensors module

  // Wait for the user button to be pressed and released
  button.waitForButton();

  // Turn on LED to indicate we are in calibration mode
  pinMode(13, OUTPUT);
  digitalWrite(13, HIGH);

  // Wait 1 second and then begin automatic sensor calibration
  // by rotating in place to sweep the sensors over the line
  delay(1000);
  int i;
  for(i = 0; i < 80; i++)
  {
    if ((i > 10 && i <= 30) || (i > 50 && i <= 70))
      motors.setSpeeds(-200, 200);
    else
      motors.setSpeeds(200, -200);
    reflectanceSensors.calibrate();

    // Since our counter runs to 80, the total delay will be
    // 80*20 = 1600 ms.
    delay(20);
  }
  motors.setSpeeds(0,0);

  // Turn off LED to indicate we are through with calibration
  digitalWrite(13, LOW);

  // Wait for the user button to be pressed and released
  button.waitForButton();


  Serial.begin(9600); // // Serial Communication is starting with 9600 of baudrate speed
  Serial.println("Ultrasonic Sensor HC-SR04 Test"); // print some text in Serial Monitor
  Serial.println("with Arduino UNO R3");
  
  
}

void loop()
{

  unsigned int sensors[6];

  // Get the position of the line.  Note that we *must* provide the "sensors"
  // argument to readLine() here, even though we are not interested in the
  // individual sensor readings
  int position = reflectanceSensors.readLine(sensors);


  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  // Sets the trigPin HIGH (ACTIVE) for 10 microseconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  // Reads the echoPin, returns the sound wave travel time in microseconds
  duration = pulseIn(echoPin, HIGH);

  // Our "error" is how far we are away from the center of the line, which
  // corresponds to position 2500.
  int error = position - 2500;

  // Get motor speed difference using proportional and derivative PID terms
  // (the integral term is generally not very useful for line following).
  // Here we are using a proportional constant of 1/4 and a derivative
  // constant of 6, which should work decently for many Zumo motor choices.

  int speedDifference = error / 4 + 6 * (error - lastError);

  lastError = error;

  // Get individual motor speeds.  The sign of speedDifference
  // determines if the robot turns left or right.
  int m1Speed = MAX_SPEED + speedDifference;
  int m2Speed = MAX_SPEED - speedDifference;


  if (m1Speed < 0)
    m1Speed = 0;
  if (m2Speed < 0)
    m2Speed = 0;
  if (m1Speed > MAX_SPEED)
    m1Speed = MAX_SPEED;
  if (m2Speed > MAX_SPEED)
    m2Speed = MAX_SPEED;

  motors.setSpeeds(m1Speed, m2Speed);

  //if (distance <20){
  //  motors.setSpeeds(0,0);
 // }
  

////////////////////////////////////////////


  // Calculating the distance
  distance = duration * 0.034 / 2; // Speed of sound wave divided by 2 (go and back)
  // Displays the distance on the Serial Monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
  
}  ```
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1 回答 1

-1

当然pulseIn是阻塞功能。Arduino 项目是开源的，您可以轻松查看源代码 这里是 C 等效countPulseASM函数，可以进行测量。

unsigned long pulseInSimpl(volatile uint8_t *port, uint8_t bit, uint8_t stateMask, unsigned long maxloops)

  {
      unsigned long width = 0;
      // wait for any previous pulse to end
      while ((*port & bit) == stateMask)
          if (--maxloops == 0)
              return 0;
 
      // wait for the pulse to start
      while ((*port & bit) != stateMask)
          if (--maxloops == 0)
              return 0;
 
      // wait for the pulse to stop
      while ((*port & bit) == stateMask) {
          if (++width == maxloops)
              return 0;
      }
      return width;
  }

如果您需要以非阻塞方式测量脉冲长度，请使用硬件计数器。

于 2022-03-05T18:09:18.693 回答