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Arduino代码

请点击此处输入图片描述

请点击此处输入图片描述

解释一下distance=duration/58得到距离的原理：

This line is used to convert a time interval into distance.

声音在空气中传播速度大概为 340m/s, 也就是 29 微秒每厘米. 因为超声波传感器测量到的是来回。 因此,是2*29=58微秒每厘米 。

串口输出的数据如图：

串口数据

使用超声波库

Ultrasonic库对SR04测距进行了封装，使得使用更为简单，可以用Arduino的库管理工具下载。

安装完之后，其自带一个简单的例子：

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然后只需要将对应的针脚更改好就行了。

如本例中使用7，8针脚

/*

 * Ultrasonic Simple

 * Prints the distance read by an ultrasonic sensor in

 * centimeters. They are supported to four pins ultrasound

 * sensors (liek HC-SC04) and three pins (like PING)))

 * and Seeed Studio sesores).

 *

 * The circuit:

 * * Module HR-SC04 (four pins) or PING))) (and other with

 *   three pins), attached to digital pins as follows:

 * ———————    ———————

 * | HC-SC04 | Arduino |    | 3 pins  | Arduino |

 * ———————    ———————

 * |   Vcc   |   5V    |    |   Vcc   |   5V    |

 * |   Trig  |   12    | OR |   SIG   |   13    |

 * |   Echo  |   13    |    |   Gnd   |   GND   |

 * |   Gnd   |   GND   |    ———————

 * ———————

 * Note: You need not obligatorily use the pins defined above

 *

 * By default, the distance returned by the distanceRead()

 * method is in centimeters, to get the distance in inches,

 * pass INC as a parameter.

 * Example: ultrasonic.distanceRead(INC)

 *

 * created 3 Apr 2014

 * by Erick Simões (github: @ErickSimoes | twitter: @AloErickSimoes)

 * modified 23 Jan 2017

 * by Erick Simões (github: @ErickSimoes | twitter: @AloErickSimoes)

 * modified 03 Mar 2017

 * by Erick Simões (github: @ErickSimoes | twitter: @AloErickSimoes)

 *

 * This example code is released into the MIT License.

 */

#include <Ultrasonic.h>

/*

 * Pass as a parameter the trigger and echo pin, respectively,

 * or only the signal pin (for sensors 3 pins), like:

 * Ultrasonic ultrasonic(13);

 */

Ultrasonic ultrasonic(8, 7);

void setup() {

  Serial.begin(9600);

}

void loop() {

  Serial.print(“Distance in CM: “);

  // Pass INC as a parameter to get the distance in inches

  Serial.println(ultrasonic.distanceRead());

  delay(1000);

}

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