主要是用超声波模块来进行距离的测量，以及编写的功能与精度见文件。-Ultrasonic module is mainly used to measure the distance, as well as writing features and accuracy in document.

使用US-015超声波模块，测出上方距离，精准大0.1厘米，(Using US-015 ultrasonic module, measured above the distance, accurate 0.1 cm large,)