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General Information

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Analog outputs are then connected to the T7:
U - channel 1 - AIN0
V - channel 2 - AIN1
W - channel 3 - AIN2
sonic speed - channel 4 - AIN3

Sample Dataset taken over 10 min:

And zoomed in to ~half a second of data taking:

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Code for taking data

Note: this will take data for 10 minutes. It also takes data at a rate of 1 kHz, which is unecessary, as the anemometer takes data at 32 Hz.

# -*- coding: utf-8 -*-
"""
Created on Tue Fri Oct 15 13:55:10 2021
@author: brodi, elanaku
"""
# saves anemometer data
from datetime import datetime, timedelta
import pandas as pd
from labjack import ljm
from sqlalchemy import create_engine
import time

DEVICE = None
PIN_VX = "AIN0"
PIN_VY = "AIN1"
PIN_VZ = "AIN2"
PIN_VSONIC = "AIN3"

sample_time = .001


db_fi = 'sqlite:///anemometer.db'

start = datetime.now()
end = start + timedelta(seconds=60*10)

def readout(PIN_VX, PIN_VY, PIN_VZ, PIN_VSONIC):
    vx = ljm.eReadName(handle, PIN_VX)
    vy = ljm.eReadName(handle, PIN_VY)
    vz = ljm.eReadName(handle, PIN_VZ)
    vsonic = ljm.eReadName(handle, PIN_VSONIC)
    return (datetime.now(), vx, vy, vz, vsonic)

try:
    handle = ljm.openS("Any","Any","Any")
    engine = create_engine(db_fi, echo = False)
    sqlite_connection = engine.connect()
    options = {"index": False, "if_exists": "append"}



    while datetime.now() < end:
        it = 200
        i = 0
        res = []
        while i < it:
            res.append(readout(PIN_VX, PIN_VY, PIN_VZ, PIN_VSONIC))
            time.sleep(sample_time)
            i += 1

        anem = pd.DataFrame(res, columns = ["t", "vx", "vy", "vz", "vsonic"])

        anem.to_sql("anemometer", sqlite_connection, **options)



finally:
    ljm.close(handle)
    sqlite_connection.close()

Relevant code for analyzing binary datafile

# -*- coding: utf-8 -*-
"""
Created on Tue Nov 30 02:11:06 2021
​
@author: brodi
"""
​
import pandas as pd
from sqlalchemy import create_engine
​
def load_pd(db_fi: str, table: str) -> pd.DataFrame:
    """
    loads pandas df from db given table name
    """
    engine = create_engine(db_fi, echo = False)
    with engine.connect() as sqlite_connection:
        df = pd.read_sql(table, sqlite_connection)
        
    return df

...

# Load datafile into pandas data frame
db_fi = r"sqlite:///anemometer.db"
df = load_pd(df_fi, "anem")

# Add columns in correct units
# because the units are +/- 5 m/s, 0 to 5 V
df['vx_ms'] = (df.vx - 2.5) * 2
df['vy_ms'] = (df.vy - 2.5) * 2
df['vz_ms'] = (df.vz - 2.5) * 2

# because sonic temperature is measured on a scale of 0 to 5 V
# from -40 to 70 C
df['tsonic'] = -40 + df.vsonic/5 * 110

#Plot data
plt.plot(df.t, df.vx_ms, label = 'Vx')
plt.plot(df.t, df.vy_ms, label = 'Vy')
plt.plot(df.t, df.vz_ms, label = 'Vz')
# plt.plot(df.t, df.tsonic/8 - np.mean(df.tsonic/8), label = 'Temp')

plt.legend()
plt.xlabel('Time')
plt.ylabel('Wind Speed (m/s)')
plt.show()

plt.plot(df.t, df.tsonic)
plt.xlabel('Time')
plt.ylabel(r'Sonic Temperature ($^o$C)')
plt.show()

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plt.show()

Which gives the first plots in the previous section.

Troubleshooting: Corrupted Data File

If for some reason the anemometer database file becomes corrupted so you can't open it or analyze the data, you can dump the data from that file into a new, uncorrupted file with the command:

$ sqlite3 old_file.db .recover | sqlite3 new_file.db

Relevant pin connections (all of which are copied from the manual)

Output pins from the anemometer (p. 15 of manual):

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To change the analog output settings, connect a RS 432 serial port to a windows computer and to the anemometer outputs. 

RS 432 serial port pin connections (p.32 of manual):

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For the serial connector we were using, pin 2 was white, pin 3 was yellow, pin 5 was orange, but apparently this isn't necessarily generically true.

The windows computer should have WIND software downloaded on it. Follow p. 46 of the manual.

Mounting plate

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through bolts are McMaster Carr 

Super-cheap hot-wire anemometer for airflow in the dome: 

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So sensor end is DB9 pins. If we use straight-through M to F DB9 cable (no swap of pins 2 and 3) then readout end is also DB9 pins. So we need DB9 female to breakout on far end. 

Easiest to just solder 4 wires into a panel mount DB9 connector.  

Clamps for mounting 20mm OD tubing

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We need two channels of A/D conversion for each unit. Conservatively, each sensor consumes 60mA at 12V. Assume we deploying ten of them. That means we need a 1A, 12V power supply. There is on-board voltage regulation on the sensor so this doesn't need to be super-well regulated. 

Box needs a a power supply for the sensors as well as A/D converter function and a data collection computer. Labjack U3-LV has 16 single-ended inputs, enough for 8 devices with both wind and temperature. We should run it off a dedicated computer, NUC or R-Pi. 

Scintillation coherence scale for acoustics

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