tips-SONIC
超音波(40KHz)
音速
https://ja.wikipedia.org/wiki/%E9%9F%B3%E9%80%9F
近似式
S=20.055 * SQRT(T+273.15) T = 摂氏 SQRT()内は絶対温度
近似値
331.5+3*T/5 T = 摂氏
概算(40Khz,25uS)
気温 | 音速 | λ(40Khz)mm | 1mの到達時間(mS) |
---|---|---|---|
15 | 340.6522187 m/s | 8.51 | 2.9355mS |
25 | 346.5128278 m/s | 8.66 | 2.8859mS |
30 | 349.1816 m/s | 8.72 | 2.8638 |
35 | 352.0495 m/s | 8.8012 | 2.8405 |
40Ksps:::2.93 / 0.025 = 117.20(samples) 200Ksps::2.93 / 0.005 = 587.10
ADC
MCP3002−I/P3.2V 75Ksps / 5v 200Ksps
Tips
https://www.jsmoc.org/kiso/pulse2.html
https://kit.socinno.com/1_3_b/
https://www.murata.com/ja-jp/products/sensor/ultrasonic/library/basic/circuit
https://toragi.cqpub.co.jp/Portals/0/backnumber/2004/10/p265-266.pdf
式
https://keisan.casio.jp/exec/user/1341380413
波動方程式
https://ja.wikipedia.org/wiki/%E6%B3%A2%E5%8B%95%E6%96%B9%E7%A8%8B%E5%BC%8F
回路
http://www.piclist.com/images/www/hobby_elec/srm1.htm
http://www.piclist.com/images/www/hobby_elec/srm1_5.htm
シミュレーション(FDTD 音響)
https://gist.github.com/peace098beat/6cb8d051919d19511d7c
https://github.com/nagataniyoshiki/FDTD_language_comparison
http://www.nhao.jp/~tsumu/Research/Intr_interferometry/interferometer.html