无弦激光音乐琴的研制

Development of String-Less Laser Music Piano

无弦激光音乐琴是一种理想的集观赏与娱乐为一体的琴,可作为课程辅助教学仪器或者儿童玩具,具有十分重要的商业价值。本文设计了一款集激光、单片机、机械、电路于一体的无弦激光音乐琴系统,主要包括多路激光模块、激光传感器模块、控制器模块以及音乐响应模块,为了实现对激光信号灵敏探测,主要针对整体电路和程序进行了设计。采用5 mW、650 nm半导体激光器作为发射源,采用光敏电阻作为接收器接收激光信号,经过STC89C52单片机的控制处理及LM386音乐响应模块的功率放大,实现音频输出。完成了无弦激光音乐琴系统的制作,整体尺寸为长10 cm ×宽5 cm ×高11 cm。对该系统发声频率进行了实验研究,可实现3个音阶,7个音调的演奏,音色清晰,实测音调频率与理论计算音调频率偏差不大于7.098 Hz。

The string-less laser music piano is an ideal instrument for viewing and entertainment,which can be used as an auxiliary teaching instrument or children’s toy,and has very important commercial value.A string-less laser music piano system,integrating laser,single chip microcomputer,machinery and circuit,is designed in this paper,which mainly includes multi-channel laser module,laser sensor module,controller module and music response module.In order to realize the sensitive detection of laser signal,the whole circuit and program are designed.The semiconductor laser with power of 5 mW and wavelength of 650 nm is used as the source,and the photosensitive resistor is used as the receiver to receive the laser signal.After the control and processing of STC89C52 single-chip microcomputer and the power amplification of LM386 music response module,audio output is realized.A string-less laser music instrument system with a size of 10 cm length×5 cm width×11 cm height was made,and the sound frequency was studied experimentally.It can play 7 scales and 3 tones with clear timbre.The deviation between the measured tone frequency and the calculated tone frequency is no more than 7.098 Hz.