Attended: Mengyuan, Creighton, Scott

• Updates:
  • Soldered new microphones to tests
  • Began testing algorithm using the new microphones
    • recalculated coefficients for mapping wind speed to real time process output
    • calculated using single trials of 5 different wind speeds
    • New microphones were tested on a breadboard
    • Results are consistent - algorithm accurately determines wind speeds, but has fairly poor precision
• To Do:
  • De-solder microphones from pcb and see if that fixes the original problem

• Updates:
  • Transferred the filtering algorithm onboard the Teensy, so the results display immediately, without me having to copy the values and run the numbers through Python.
    • Using 1k samples, the results were pretty consistent (varies by around 1 microsecond). However, I noticed that the experiment was very sensitive to its surroundings. Even moving my hand around (about 2 feet away) was still enough to cause fluctuations in the results.
    • The good news is that if I keep my hands still, the results are pretty consistent.
  • Constructed a 40kHz square wave using a 555 timer and plan to use that to drive the transducer emitter.
• To Do:
  • Gather some data using our current experimental setup.
  • Start implementing amplifier with the transducers so the Teensy can control the emitter.
  • Look into using high speed ADC found here: https://forum.pjrc.com/threads/25532-ADC-library-update-now-with-support-for-Teensy-3-1. Only use a limited bit precision to try and get the highest speed.
  • Look into using thresholding to detect a wave, and then run some ADCs to determine the phase shift afterwards.

Contributing authors:

Created by mwu on 2017/03/18 01:00.